Aviation Critic & Enthusiast: Time to "Scale Back" our Expectations for Composites?

Monday, January 4, 2010

Time to "Scale Back" our Expectations for Composites?

Happy New Years greetings to all!

Although as we start a new decade, I recall some of the year 2K hubbub- which leaves me mindful of the debate over exactly when a new century starts, and presumably, how to designate decades...BTW, the Royal Observatory also says Jan 1, 2001- but what the heck, we have other things to worry about, so I'll stick with Jan 01, 2010. (Now about Tiger Woods...).

I have to admit some satisfaction with our last thread, in examining why the 787 wings appeared to flex so much (incorrect aspect ratio in some videos resulted in an exaggerated depiction of the radius of curvature), and why they really DO flex so much (higher yield strength x4 aluminum, so only 1/4 as much as used; so despite the fact it is x2 as stiff, structures deflect twice as much (1/4 x 2), roughly (very!) speaking.

What I have less satisfaction with, whether composite airplanes are (or are not) lighter than aluminum airplanes. Which, of course, as an aviation "critic", and "enthusiast", prompted a simple comparison of the 787's nearest stablemates in the Boeing barn, the 767 on the smaller side, and the 777 on the larger side. I have always considered structural efficiency to be measured by empty weight to maximum weight, given other factors being about the same:

* Commercial service (not ruggedized for military operations)
* Pressurized (significant structural stresses involved)
* Jet powered (Similar systems)
* Operating environment (all more or less 35K feet and Mach 0.8-ish)

I had three expectations:

1) A "scaling" effect, that the larger (At least, higher MTOW) an airplane was, the "better" it's structural efficiency would be (empty/MTWO)
2) Newer aircraft would benefit from CAD analysis and be tailored for ultimate structural efficiency, and have superior empty/MTOW ratios
3) Composite airplanes (well, as Baron pointed out, -partially composite) would have better ratios than all aluminum airplanes.

The first expectation was reasonably well met, but the other two pointed to decidedly "disruptive" conclusions! (Now, there is probably a reason for this, but dang if I know what it is...)

Of course, this led to that, and after looking at the 787's nearest family members, I remembered what I have been told about the Boeing 757- that a) it was designed during the energy crunch of the 1970's, and as such, was designed to be unusually light, an as such, included some unusually expensive structural innovations, such as extra lightening holes, etc- whether or not this is true, I'm not sure, but when the 757 was discontinued in favor of the latest and longest versions of the 737, I wondered how much of the purported manufacturing expense savings of going to a "one (737) family" product came from commonality, and how much came from the 757 design itself. So I included the 737 lineup to compare to the 757 versions.

And the 757 was designed to replace the 727, so I looked at it too. Okay, that's a pretty old jet, so how about the other icon-ic (thank you very much!) jet of that era, the 707? How about the extreme of the Boeing product line, the 747, and if that "heavy", how about it's contemporaries, the DC-10 (and MD-11 derivative) and L-1011. How about the other Douglas jets, the DC-9 (and MD-xx derivatives). Not to offend our European friends, how about the Airbus lineup?

And neither would I want to offend our Canadian nor Brazilian friends, especially if the smaller DC-9/MD-95 and 737's are mentioned, the Bombardier CRJ-series and Embraer ERJ-series were included. And then other (original) "regional jet" aircraft were considered- the Fokker 70 and 100, the Dornier 328Jet.

And what the heck, if I looked at DC-9's, why not DC-8's? And how about it's contemporary, the Consolidated Vultee/General Dynamics/Convair series. And if I'm going back to the older jet airliners, why not go ALL the way back, to the Comet?

If considering "unusual" (rare in the US, nowadays, anyway) airliners such as the Convairs, how about the Russian Ilyushins? At this point, I decided just to include every main-stream (even if non-USA) jetliner that I could think (and find in Wikipedia or Airliners.net): the French SUD Caravelle, the British Vickers VC-10 (I've actually seen these in military guise); the Russian Tupolev and Yakovlev, and the British "regional-ish" jet the BAC-111.

And for fun, I included the British/French Concorde and Russian Tu-144 SST's, and the Russian Antonov STOL jet transport. (The STOL outcome was expected, the SST was not).

Anyway, that's the train of thought that led to this compilation.

The weights are pounds, and the the "empty" weight is "operating empty", if I could find it (but the differences usually weren't too great). The radio is Empty/MTOW.

Aviation enthusiasts will recognize the names of these- but just in case we no longer recognize the airplane, Airliners.net/Aircraft-data has a listing of most of these, and there are also generally Wikipedia entries available.

Here's the initial comparison I was curious about, regarding the 767-787-777 comparison:

Manufacturer	Airliner	Empty	MTOW	Ratio
Boeing	777-200	307000	545000	0.563
Boeing	777-200ER	315000	656000	0.480
Boeing	777-200LR	326000	766000	0.426
Boeing	777-F	326000	766000	0.426
Boeing	777-300	353600	660000	0.536
Boeing	777-300ER	366940	775000	0.473
Boeing	787-3	223000	375000	0.595
Boeing	787-8	242000	502500	0.482
Boeing	787-9	254000	547000	0.464
Boeing	767-200	176650	315000	0.561
Boeing	767-200ER	181610	395000	0.460
Boeing	767-300	189750	350000	0.542
Boeing	767-300ER	198440	412000	0.482
Boeing	767-300F	190000	412000	0.461
Boeing	767-400ER	229000	450000	0.509

That was a tasty appetizer, but here's the "main course". The "Top 10" contained some surprises to me- half of them are freighters. (I thought the floor reinforcements, cargo handling equipment, and beef up around the large cargo door cutouts might "outweigh" weight savings obtained from the removal of passenger accommodations and accouterments- but it looks like that is not the case: the "stripped down" freighters are a bit lighter).

The other five "Top 10" finishers included some real surprises too:

The venerable DC-8, grand-daddy of more modern jet "freight dogs", is still showing the kids how it's done. (Well, it did really well in our comparison anyway). First flight of the original DC-8 was on May 30, 1958.

The Concorde SST was certainly not one I would have expected near the top. The rival Tupolev Tu-144 SST did well also, at 0.472 (versus 0.425). The Concorde first flew on March 2, 1969; the Tu-144 first flew on December 31, 1968.

The Boeing 777-200LR was in the top 10 also (as was the 777-Freighter, largely based on the -200LR). I expected the 777 to do well in this comparison- and this is even better than I expected. The first flight of the original 777 was on June 12, 1994.

The Russian Ilyushin IL-62 was a bit of a surprise- firstly, it is Russian, and I think of the stereotype of "rugged" (read: heavy) construction methods. Apparently, this is not (always, anyway) the case- it matched the Airbus A380-800 freighter. It features the funky twin-pod aft-mounted engines (total of 4), similar to the Vickers VC-10 Super of that era, which did well itself (0.468 versus .428). The Ilyushin original version flew in September 1963, the Vickers original version flew on June 29, 1962.

And, the upcoming A350 rounds out this list- although it is still a "paper airplane" (or "paperless airplane", as it is designed with CATIA). And it still hasn't been rolled across a scale- first flight is scheduled for 2012.

Manufacturer	Airliner	Empty	MTOW	Ratio
Douglas	MD-11F-HW	248567	630500	0.394
Douglas	MD-11F	248567	610000	0.407
Douglas	DC-8-63CF	146300	355000	0.412
Douglas	DC-8-62	141903	335000	0.424
Aerospatiale-BAC	Concorde SST	173500	408000	0.425
Boeing	777-F	326000	766000	0.426
Boeing	777-200LR	326000	766000	0.426
Airbus	A380-800F	556000	1300000	0.428
Ilyushin	IL-62	153000	357586	0.428
Airbus	A350-900 (est.)	255075	591000	0.432
Douglas	DC-8-32	134000	310000	0.432
Ilyushin	IL-62M	157360	363760	0.433
Boeing	707-320B	146400	333600	0.439
Douglas	DC-8-63	153749	350000	0.439
Boeing	747-400ER	406900	910000	0.447
Boeing	747-400	393263	875000	0.449
Douglas	MD-11C-HW	283975	630500	0.450
Douglas	MD-11-HW	283975	630500	0.450
Airbus	A310-300F	162900	361600	0.450
Lockheed	L-1011-500	232749	510000	0.456
Douglas	MD-11CF-HW	288296	630500	0.457
Douglas	DC-8-61	148897	325000	0.458
Airbus	A340-500 HGW	385000	840000	0.458
Airbus	A340-200	280000	610000	0.459
Airbus	A340-500	377000	820000	0.460
Boeing	767-200ER	181610	395000	0.460
Boeing	747-200B	383000	833000	0.460
Boeing	767-300F	190000	412000	0.461
Douglas	MD-11CF	288296	625000	0.461
Douglas	MD-11ER	291120	630500	0.462
Boeing	747-200SP	325000	700000	0.464
Boeing	787-9	254000	547000	0.464
Boeing	707-020	103145	222000	0.465
Douglas	DC-10-30	266191	572000	0.465
DeHaviland	Comet-4	75400	162000	0.465
Douglas	MD-11C	283975	610000	0.466
Boeing	737-200HW	60600	129500	0.468
Vickers	VC-10 Super	156828	335000	0.468
Douglas	DC-8-73	166500	355000	0.469
Airbus	A340-300	287000	610000	0.470
Airbus	A330-200F	240000	510000	0.471
Vickers	VC-10	146980	312000	0.471
Douglas	MD-11	283975	602500	0.471
Boeing	747-300	392800	833000	0.472
Tupolev	Tu-144 SST	187400	397000	0.472
Douglas	DC-9-30	57190	121000	0.473
Convair	990	120560	255000	0.473
Boeing	777-300ER	366940	775000	0.473
Boeing	707-120	122533	257000	0.477
Boeing	727-200	100000	209500	0.477
Airbus	A340-600 HGW	401000	840000	0.477
Boeing	777-200ER	315000	656000	0.480
Boeing	787-8	242000	502500	0.482
Boeing	767-300ER	198440	412000	0.482
Airbus	A300-600F	180700	375100	0.482
SUD	SE210-III	49000	101400	0.483
Tupolev	Tu-154	95900	198415	0.483
Airbus	A340-600	392000	810000	0.484
Douglas	DC-9-40	58670	121000	0.485
Boeing	747-8i	472900	975000	0.485
Ilyushin	IL-96	267860	551160	0.486
Douglas	DC-10-40	270213	555000	0.487
Convair	880	94000	193000	0.487
Boeing	747-100	358000	735000	0.487
Boeing	737-400	73040	149710	0.488
Ilyushin	IL-96M	291887	595238	0.490
Boeing	737-700ER	84100	171000	0.492
Lockheed	L-1011-200	231600	466000	0.497
Boeing	757-200-PW	127520	255000	0.500
Douglas	MD-87-JT8D-217C-ER	74880	149500	0.501
Boeing	757-200-RR	127810	255000	0.501
Airbus	A310-300	183300	361600	0.507
Airbus	A380-800	610000	1200000	0.508
SUD	SE210-12	65000	127800	0.509
Boeing	767-400ER	229000	450000	0.509
Airbus	A310-200F	159600	312342	0.511
Douglas	DC-9-50	61880	121000	0.511
SUD	SE210-10	58800	114600	0.513
Boeing	737-500	68850	133210	0.517
Airbus	A330-200	264000	510000	0.518
SUD	SE210-VI-N	54800	105800	0.518
Airbus	A321-200	107000	206000	0.519
Douglas	MD-81-JT8D-217A	77888	149500	0.521
Boeing	757-300-PW	142110	272500	0.522
Douglas	MD-88-JT8D-219	77976	149500	0.522
Lockheed	L-1011-1	224579	430000	0.522
BAC	111-500	54582	104500	0.522
Boeing	757-300-RR	142400	272500	0.523
Boeing	737-800	91108	174200	0.523
Douglas	MD-87-JT8D-217C	73274	140000	0.523
Boeing	737-300HW	72490	138500	0.523
Boeing	737-200	60600	115500	0.525
Boeing	737-900ER	98495	187700	0.525
SUD	SE210-VIR	58000	110200	0.526
Douglas	DC-10-15	240171	455000	0.528
Airbus	A300-600R	200400	378500	0.529
Canadair	CRJ-200F-LR	28212	53000	0.532
Tupolev	Tu-204-220	130070	244155	0.533
Douglas	MD-90-55	91900	172500	0.533
Fokker	F-100-Tay650	54100	101000	0.536
Boeing	777-300	353600	660000	0.536
Airbus	A330-300	274000	510000	0.537
Embraer	ERJ-190-IGW	61905	114198	0.542
Boeing	767-300	189750	350000	0.542
Airbus	A319-100	90000	166000	0.542
Airbus	A300B4	198132	364980	0.543
Boeing	737-900	94580	174200	0.543
Boeing	737-700	84100	154500	0.544
Yakovlev	yak-40D	20725	37920	0.547
Boeing	737-600	80031	145500	0.550
Douglas	DC-9-10	49900	90700	0.550
Embraer	ERJ-145LR	26470	48000	0.551
Antonov	An-72 STOL	42000	76060	0.552
Ilyushin	IL-86-late	253531	458560	0.553
Airbus	A320-200	94000	170000	0.553
Tupolev	Tu-154M	121915	220460	0.553
Canadair	CRJ-200F-ER	28212	51000	0.553
SUD	SE210-11R	63400	114600	0.553
Embraer	ERJ-195-IGW	63867	115278	0.554
Douglas	MD-81-JT8D-209	77888	140000	0.556
Canadair	CRJ-1000ER	51100	91800	0.557
Embraer	ERJ-140	25900	46500	0.557
Embraer	ERJ-190LR	61905	110891	0.558
Douglas	DC-10-10	240171	430000	0.559
Canadair	CRJ-900LR	47250	84500	0.559
Boeing	767-200	176650	315000	0.561
Embraer	ERJ-170LR	48082	85516	0.562
Embraer	ERJ-135ER	23554	41888	0.562
Boeing	777-200	307000	545000	0.563
BAC	111-400	49857	88500	0.563
Douglas	MD-90-30	88000	156000	0.564
Airbus	A310-200	176312	312342	0.564
Ilyushin	IL-86-early	259043	458560	0.565
Fokker	F-100-Tay620	53740	95000	0.566
Embraer	ERJ-145ER	25722	45415	0.566
Canadair	CRJ-1000	51100	90000	0.568
Embraer	ERJ-170LR	46605	82011	0.568
Embraer	ERJ-195LR	63867	111971	0.570
Embraer	ERJ-135LR	25176	44092	0.571
Canadair	CRJ-200LR	30292	53000	0.572
Boeing	737-100	61864	108218	0.572
Canadair	CRJ-900ER	47250	82500	0.573
Canadair	CRJ-700LR	43200	75000	0.576
Airbus	A318-100	87000	150000	0.580
Embraer	ERJ-175	48082	82672	0.582
Boeing	737-300	72490	124500	0.582
Douglas	MD-95 (717-200) HGW	70790	121000	0.585
Canadair	CRJ-900	47250	80500	0.587
Embraer	ERJ-170	46605	79343	0.587
BAC	111-200	46404	79000	0.587
Yakovlev	Yak-40	20725	35275	0.588
Embraer	ERJ-190	61905	105357	0.588
Boeing	727-100	100000	169000	0.592
Embraer	ERJ-195	63867	107562	0.594
Canadair	CRJ-1000EL	51100	85968	0.594
Boeing	787-3	223000	375000	0.595
Canadair	CRJ-700	43200	72500	0.596
Dornier	328JET_HGW	20710	34524	0.600
Yakovlev	Yak-42D	76092	126765	0.600
Yakovlev	Yak-42	76058	125660	0.605
Dornier	328JET	20600	33510	0.615
Canadair	CRJ-100	29180	47450	0.615
Tupolev	Tu-204	128530	208550	0.616
Fokker	F-70	49985	81000	0.617
Tupolev	Tu-134	60627	98105	0.618
Tupolev	Tu-334-100D	75785	119975	0.632
Douglas	MD-95 (717-200)	69830	110100	0.634
Tupolev	Tu-334-100	66250	101630	0.652
BAE	146-200	73415	93035	0.789

134 comments:

Phil Bell said...: I was rather stunned with just how well the older jetliners did in this comparison. As Baron and others pointed out, even the newest "composite" airplanes are only half composite, but I figured with advanced computer modeling, a significant amount of weight could be trimmed. On the surface, it looks like maybe the slide rule boys did a pretty darned good job, some 40-50 years ago.

One consideration comes to mind- it is probably structurally more efficient to haul fuel than haul people- you can cram and squeeze fuel into nooks and crannies, where people just should not be put. (Although flying on most regional jets challenges that thinking). And the older jets, with higher fuel consumption, probably had to haul a higher percentage of fuel:passengers, so they might have had more fuel in the wings.

So let's consider the DC-8-62 versus the 777-200LR

Aircraft: ......... DC8-62 ..... 777-200LR
Empty Wt: ...... 141903 ..... 326000
max TOW: ....... 335000 ...... 766000
Fuel (gal): ....... 24275 ....... 53515
Fuel (lbs): ....... 162885 ...... 359085
Range (nm): ..... 5219 ........ 9380
Pax (3 class): ...... 180 ....... 301
Pax (2 class): ...... 220 ....... 400
Pax (1 class): ...... 259 ....... 440
Cruise Speed: ..... 459-479 ... 490
Empty+max fuel: ... 304788 .. 685085
Payload @max fuel: .. 30211 .. 80914
Average Pax (lbs): ... 175 .... 180
Pax @max fuel: ...... 172 ..... 449

Let's check out my "more structurally efficient to fly fuel in the wings than passengers in the cabin theory (this comparison assumes most of the fuel is carried in the most efficient place, the wing), by using Max fuel load / Empty Weight

Payload*nm/empty: ... 114.8% ... 110.1%

So yes, the DC-8-62 carries slightly more weight in the wing than the 777-200LR, but they are not all that much different.

(Which rather makes me think, the idea of "structural efficiency" using empty/mtow has some validity).

Now, let's look at overall efficiency, how much payload, can be flown how far, using how much fuel. (Also convert payload in lbs to passengers, using 180 for both the DC8 and 777, which yields theoretical 167.84 on the DC8, and 449.52 on the 777- I think the airlines indeed use "tenths of a person" for their floor plans! :(

So let's take Passengers, multiply by range, and divide by max fuel:

Pax-nm/gal: ... 36.09 ...... 78.79
-or, using statue miles per gallon:
Pax-sm/gal: ... 41.86 ...... 91.4

Which, is why airlines buy new airplanes, I suppose.

But, I would say, perhaps we have demonstrated that the structural efficiency is quite good for the older airplanes, and the "seat mile per gallon" improvements must be due to refined aerodynamics, propulsion, and systems efficiency, rather than outdated structural design methods.

If that's the case, I don't see composites having too much advantage from a "performance" standpoint.

There might be some "cost performance" advantages (?): lower assembly costs (labor-versus-infrastructure), maintenance (especially corrosion), and service life (fatigue) improvements.

(The DC-8's sure flew for a long time though-
"The Douglas DC-8 is a four-engined jet airliner, manufactured from 1958 to 1972...details of the DC-8 design allowed it to hold slightly more cargo than the 707; hundreds of re-engined examples remain in freighter service to this day, while commercial 707 service had largely ended by 2000."; January 4, 2010 at 11:41 PM
Phil Bell said...: It was incredibly kludgy to put the table on the headline post- 44 pages of gibberish html code was generated. I use Firefox for a browser, and it finally came out looking okay in that browser- hope it is readable with Explorer.

I eventually found what is either the world's best
1) html code converter, or
2) the worlds slickest virus generator (for unsuspecting dummies like me that can't read html).

(Ought to be a better way!); January 4, 2010 at 11:47 PM
julius said...: Phil,
happy new year and thanks for this comparison!

Sorry to say - you missed one species of bird which might explain a lot:
Gliders!

Old ones were made of wood or plywood (composite!?) and cloth and are lightweights.
Modern gliders are made of composites and are heavier ( and bigger and faster)!.

Compare the surfaces of a modern glider and a modern 737-800 or a Beech 200 GTI...different worlds!

As Beedriver pointed out designing mainly with composites is completely diffent to designing with AL or AL LI alloys if one wants to get a real advantages!

Are there composite wedges (for splitting timber)?

The (empty) weight is only one aspect!

Julius

Is all composite Concord possible?
I read that the surface of the bird gets real warm an that therefore corrosion never became a problem.; January 5, 2010 at 1:53 AM
Shane Price said...: Happy 2010, to one and all....

A fine, detailed post to begin the year with Phil, with lots to contemplate.

I've been a passenger on many of the birds you listed, going right back to the Comet. One of the things that has very clearly changed in the 6 decades since 'commercial' jets took to the air is the focus on comfort. I suspect that these new 'interiors' adds significantly to the airframe, and that this ratio has gone the opposite way to the overall efficiency brought about by modern materials.

Think about it. More galleys with additional facilities and food storage. Heavier, wider and taller seats (and more of them) with entertainment built it. The overhead compartments, multiple toilets, sophisticated air conditioning, individual lighting controls, etc etc.

No wonder the freighter versions don't weigh any extra....

Concorde is a special case, however. The delta wing (very thin) together with the use of fuel as 'mobile ballast' meant that the only passenger carrying supersonic jet so far has a 'favorable' rating. What is not as clear is that it took twice as much fuel (per paying passenger) to get the whole system across the Atlantic...

The other area that might bear further examination is the cycle ratio. How many landings v MTOW? What, in other words, is a reasonable lifetime for one of these new composite airframes.

Remember the Comet, and what happened when new(ish) materials met unanticipated stresses.

Shane; January 5, 2010 at 3:42 AM
Soccer Dad said...: Shane:
Excellent Points - it seems that Phil has either an axe to grind with composites or with the use of composites in the 787 - not sure which.

Phil:
Would you think that the major airframers would make the significant investments in composites if they did not provide any advantage. Your simplistic comparisons between the old methods of manufacture and the 787 don't take a lot of things into consideration.

Composites offer the ability to achieve complex shapes that would could not be fabricated or fabricated economically using conventional methods and these shapes allow some of the aerodynamic efficiencies which you allude to in your post.

Additionally, because of our lack of history with composites, the structures are typically over designed by several factors of safety to compensate for some of the uncertainties associated with the manufacturing processes - inevitably, our design methodologies and manufacturing techniques will improve such that we will achieve greater structural efficiencies.

Do I think it is time to scale back our expectations for composites - no, I think it's time to increase our understanding of composites before we post.; January 5, 2010 at 9:36 AM
Soccer Dad said...: This comment has been removed by the author.; January 5, 2010 at 9:36 AM
Deep Blue said...: Jeez, that was a hell of a post!

Two quick comments:

1. jet transports are an old, mature design. OEM's captured better margins by focusing on the cockpit avionics, controls (wrong focus I would argue). As you note, 787 is still chugging along at .8, fl350: big yawn.

2. More innovation probably in he thrust department (both cost, SFC, reliability, efficiency).

Next big breakthrough? Supersonic and hypersonic: back to the real value of aircraft: speed!! And here the real challenge is thrust, not airfoil design.

Phil: did you look at pro forma specs on the BWB (blended wing body) compared to traditional tube fleet?; January 5, 2010 at 9:55 AM
Beedriver said...: I had a long talk with my daughter who is an aircraft composite designer actually doing the layup design and selection of composite materials.

she said at this time fatigue mechanisms are not understood in composites. thus Designers must be very conservative in their design. also the matrix system and exact characteristics of the fiber reinforcement interact strongly with each other and especially with the bond characteristics of the fiber/matrix interface. the failure modes of composites are also not very well understood and in addition the fasteners used to fasten composite panels to each other and to other major components are very tricky. I feel composites have a bright future however In general there is a lot of development necessary to fully utilize the advantages of composites. New tests need to be developed to understand the fiber/matrix interface and how to make consistent bonds. It is a technology still in its infancy and as such conservative design and proven expensive processes like autoclaves etc must be used to guarantee quality when in most cases it is not probably necessary. thus excess weight will be the norm especially in cases where failure cannot be possible such as in airliner design.; January 5, 2010 at 10:06 AM
Beedriver said...: there is a reason that the cirrus is heavier than the Cessna.

Cirrus uses mostly glass reinforced laminates which are much less expensive to build and heavier than equivalent aluminum structures. in addition certification and liability insurance requires that a composite structure must have a larger factor of safety. If you look at Cirrus accidents very few actually result in the airplane coming apart in the air compared to the Malibu where many of the accidents result in inflight breakups. they both meet the same certification requirements but you do not see a push to strengthen the Malibu as it "meets certification requirements"

thus if advanced composites using carbon fibers become cost competitive with aluminum structures and enough is known about failure limits to design them less conservatively then advanced composite will become much more utilized in small aircraft design.; January 5, 2010 at 10:48 AM
the Team said...: I think Beedriver asked about Epic. Multiple companies related to and including Epic have filed bk. Looks like there is some consolidation to get actions into OR Fed court. Epic, et al are still facing a suit from builders. There has been a move to have this also consolidated with bk. Court is still hearing motions on it, however. It appears as if this will be messy for awhile.; January 5, 2010 at 11:48 AM
Soccer Dad said...: Bee:
Your daughter is absolutely correct, there are several different mechanisms which we are not well understood and we continue to learn every day. Next year will cap 20 years of designing and testing composite structures and I know that for me, every year, sometimes every month I've learned more and more about the behavior of composite structures - some of it intuitive, a lot of it, not so much.

My point is simply that to make the overly simplistic comparisons which Phil has attempted, do more harm than good and really are not very enlightening or informative and somewhat disappointing considering the forum.; January 5, 2010 at 12:15 PM
michal said...: I recall reading long time ago from many good aviation sources (AW&ST, FLYING, etc) that no weight advantage is associated with aircraft composite constructions. I don't think Boeing even listed weight among 787's main beneficiaries. It is stuff like long term maintenance and material fatigue where composites hold a significant advantage over aluminum counterparts.; January 5, 2010 at 12:43 PM
gadfly said...: Soccer Dad and Beedriver

There is much technology dating back millenia which seems to have been overlooked in the "modern" use of fiber re-enforced composites . . . as in "trees". For instance, study the "medullary" rays in oak and other woods. The dictionaries will state the purpose of these rays is to transport nutrients (sap) between the center and outer wood, but an overlooked purpose is to "lock" the layers of summer and winter growth, to prevent splitting along the "shear" lines.

(Most comments on these rays deal with their beauty in finished wood furniture, etc., and a search will probably be most frustrating, when looking for the primary reason for these rays. But anyone who has spent much time working with wood, especially "oak", will realize their function.)

When this sort of thing is applied to fiber re-enforced composites, a cross linking of layers is seen as critical. Delamination of the layers is a major problem, in highly stressed shear boundaries between layers. A cross linking would greatly reduce this problem.

Another problem, recently brought to my attention, is the lack of metal inserts in certain critical areas of attachment in the "fin" on the Airbus. I fully trust the source of this information, but have not yet verified it from a second source. That, combined with drilling holes through fibers, is another "no-no!".

And there is a long list of other potential problems . . . "heat" over 400 degrees F, for instance, a major problem with polymers when going trans-sonic, etc.

gadfly; January 5, 2010 at 12:49 PM
forest said...: Sorry for being off-topic and lengthy, but I wanted to add some information to a post (Baron, I think?) on the prior thread. I’m more of an enthusiast than a critic here.

I haven’t read the full PilotMag article but I have researched Excel-Jet vs US Government (Sport-Jet crash, trial May 2010) as well as other GA wake cases. [And yes, some of their funding dried up due to the crash, understandable.]

FYI, imho, these guys are really stepping up for all of GA by bringing this case. The FAA constantly wants to blame the pilot for controller error--see Dallas and other IG reports. This is particularly true with wake accidents. Wake encounters near the ground end up with fatalities--not some minor aircraft repair. There are a lot of politics behind this. The FAA is exerting a lot of effort to cover up wake accidents (this one and others) because of their mandate to reduce separation. Gov. publications indicate that wake vortex is the biggest obstacle to reducing separation times. If the FAA can reclassify any wake encounter as pilot error then it is significantly easier to establish new separation criteria. By reducing separation (in certain situations) the FAA satisfies its mandate (justifies its budget) and in the process we in GA are often less safe.

Now, these types of cases have been pretty easy for the gov. because the pilots die in the crashes and can never defend themselves or explain what really happened. This is going to be a landmark case. If the gov. wins some very dangerous and scientifically inaccurate precedents will be set. [There was another article yesterday in the WSJ on the apparent misconduct by DOJ attorneys for a purely political agenda. I think it will be shown the same thing is going on in this case.]

The Sport-Jet guys are trying to do what is right for aviation--it sure would be easier for them to not fight this fight! I think GA needs to get behind this case and realize what’s at stake for every pilot, whether owner/operator or biz jet.

As Gadfly always says integrity and ethics matter!

Now back to composites vs alum.; January 5, 2010 at 1:46 PM
gadfly said...: This comment has been removed by the author.; January 5, 2010 at 2:04 PM
gadfly said...: forest (for the trees):

Your comments are far more on target than you may realize.

Back, a long, long time ago, I had far more problems with the "experts" in fiberglas composites than with the man who had no background in "laying up" fiberglass re-enforced panels. The experts in any field have an agenda, and their pride precludes learning new principles. The inexperienced could be "trained" to lay the chopped mat into the resin, fully wetting out the fibers as they sank, while the "expert" would faithfully work with a slotted roller to force out the entrapped air bubbles (after pouring the resin into the mat). Why? . . . because he had always done it that way, and refused to learn that maybe there was a better way.

Require that every Government bureaucrat "drive around in a small aircraft" for a few years and he'll change his attitude about taking off or landing close behind a heavy aircraft. Those horizontal tornadoes don't often allow a second opportunity to "learn" from a mistake.

gadfly; January 5, 2010 at 2:06 PM
Beedriver said...: Phil I applaud your trying to make sense out of what we see and hear out there.

I find that the start of knowledge is asking a question and then working to find some correlation with the information at hand and when that may not satisfy the question, working to further search out the base causes. The reason for the increased efficiency of the 787 may not be the fact it uses a lot of composites but noticing an interesting thing like the fact that the 787 wings seem to deflect more and then trying to understand why is a great thing to do.

To say that we should not try to understand things like this and "leave it to the experts" is to be doomed to never grow in understanding and knowledge.; January 5, 2010 at 2:40 PM
Baron95 said...: Phil, Congrats. A pretty impressive post to start the decade. While I agree with Soccer Dad, that there are many factors involved in comparing these planes, I still appreciated looking at the data at a glance on a single table.

A couple of points.... addressing some comments....

1 - Cirrus is heavier than a comparable Cessna, because it has a much larger cabin (much wider), better interior appointments, carries a parachute and rocket, has wing/tail/controls designed with a VNE that is 35-40 KTS faster, etc, etc, etc.

If you want to compare fiber-glass GA planes with aluminum GA planes compare SR22 to Ovation. Speeds and range are similar, and the Cirrus walks away by a huge margin in cabin space and payload. CIrrus saved about 50% in the weight of the wing spar going from fiberglass to carbon fiber. So, there are composites and there are composites.

2 - Composites (like 787) allow much more comfortable levels of humidity in the cabin, without inducing corrosion - that alone is a big advantage. It also, allows higher pressure differential and more cycles before inducing fatigue. So 787 will have a cabin altitude some 2,000 ft lower than 777. Again - huge for comfort on those 16 hr flights.

So lets say that an aluminum 787 with 10% humidity and 8,000ft cabin altitude and 10,000 cycles weights the same as a CFRP 787 with 30% humidity, 6,000 ft cabin, and 30,000 cycles. Which one would you buy?

In this case, some of the composite weight savings are allocated to comfort (higher pressure differential and more cycles).

Another advantage, the 787, given it's composite barrel, thinner walls, will allow for 9-abreast while being much narrower than a 777 (on the outside). So floor area utilization will be higher on the 787.

Also, look at things as the number of LD3 containers the 787 can carry - it's cargo optimization is also very high.

Also be careful comparing 4-engined to 3-engined to 2-engine airliners. There are weight efficiencies when you go to more engines (believe it or not). But mostly be careful comparing jet or low bypass turbofans to high-bypass-turbofan-powered jetliners.

A DC-8 engine with 5,000 hrs max time on wing is much, much, much, much lighter than a GE115B or Trent 1000 with those huge fans and 20,000 hrs on wing. And *A LOT* of weight goes into making those engines achieve 330 ETOPS.

So, while I appreciate the numbers, it is *CRITICAL* to keep things in perspective.

Happy 2010.; January 5, 2010 at 3:01 PM
Phil Bell said...: Howdy all,
I'm glad others find the table of weights as interesting as I did- the data had many surprises (to me anyway).; January 5, 2010 at 6:53 PM
airsafetyman said...: "A DC-8 engine with 5,000 hrs max time on wing is much, much, much, much lighter than a GE115B or Trent 1000 with those huge fans and 20,000 hrs on wing."

Nope. The new big engines are much lighter in terms of weight per pound of thrust.

The JT-8D originally used on the DC-8 delivers 17,000 pounds of trust at its max continuous rating and weighs about 4,500 lbs. The thrust to weight ratio of the JT-8D is 3.7 pounds of thrust for each pound of engine weight.

The RR Trent delivers about 77,000 pounds of thrust at its max continuous rating and weighs about 13,400 pounds. The thrust to weight ratio of the Trent is 5.7 pounds of thrust for each pound of engine weight.; January 5, 2010 at 7:42 PM
Phil Bell said...: Hi Shane,
I remember flying on many of the airplanes in the table too- going to the airport doesn't seem to offer the same variety lately, compared to earlier decades...

(No- if some wonder- I'm not referring to biplanes! :)

One of the biggest surprises to me was the Concorde's weight ratio. I had figured it would have a lot of heavy structure for the higher dynamic pressures associated with supersonic flight, the added material required to stiffen a thin high-speed wing, the complicated swing wing mechanism and "drooping nose", large landing gear to provide adequate rotation angle, and more generally, being a 40+ year old design. But that doesn't seem to be the case...

On the other hand, I had expected the regional jets to be the higher performers, but they seem to be in the worse end of the spectrum. (Perhaps it is a "scaling" thing- larger airplanes are -somewhat- inherently more weight efficient- this hypothesis is intuitively pleasing, but the table demonstrates mixed results- it would seem the primary advantage of making a larger version of an airplane, is to make a larger version of an airplane- rather than a more efficient version of an airplane).

The surprises were not only at the "good" end of the spectrum:

1) I've heard for a decade "how good" the MD95/B717 was, and what a shame it was to cancel it. I have to confess, I rather liked what I'd read about it, and shared these laments. But at 0.634, that little piggy comes in 3rd worse (out of 169 comparisons).

2) I always liked the 4-engined short-haul BAe-146, having flown on them when AirCal and PSA were still around. But it came in dead last, at 0.789. The surprise was: I figured it would not do well, but did not expect it to do so spectacularly poorly.

Sandwiched in between these two toads, was the rather blimpish looking Tu334, with a ratio of 0.652 . Kinda cute- in a, well, toady sort of way. It gets points for looking like a sturdy "manly" airplane though, rather than some too-long (and too skinny!) "supermodel". Make that a "super-stretch model". (The CRJ-1000LR tied the ERJ-195, with a relatively unimpressive 0.594; the tie is deliciously fitting, as the two models are direct competitors).; January 5, 2010 at 8:17 PM
Phil Bell said...: "it seems that Phil has either an axe to grind with composites or with the use of composites in the 787 - not sure which"

Nothing could be further from the truth.

And one should not infer my judgement is shaded by the fact that I think composite airplanes will undergo spontaneous explosive decompression like the early Comets, hurling unsuspecting screaming passengers tens of thousands of feet to their deaths- the lucky ones being alive for a few extra minutes during the plunge- the remaining victims either:

1) pureed by the monstrous high-bypass engines (I figure most folks will be chopped into an average of three pieces by the front fan- although women and children might only be cut in half- before ingestion by the turbine section), or

2) asphyxiated by the toxic fumes of burning composites, or

3) electrocuted by the high voltage DC distribution system of the bleedless engines- or sizzle on the high voltage AC system.

Of course, impalement by splintering composites is always a concern too.

As is the possibility of being vaporized when a lightning strike hits the composite fuel tanks. (Although one might get lucky, and be killed directly by the lightning).

Me- being "anti-disruptive"??
Tsk, tsk!!

.); January 5, 2010 at 9:17 PM
Phil Bell said...: Forest,

No need to worry about being off-topic, or lengthy- it's an "open floor"- thanks for your post.

Of course, if you would say something nasty about composites, I would appreciate it.

( !! Just kidding !! :); January 5, 2010 at 9:34 PM
Phil Bell said...: Hi SoccerDad,

No axe to grind by me (I "don't have a dog in this fight"- how about you? :) I liked the picture of the scale, because of the timely association with proverbial New Year's resolutions- but the headline was based on the direction the data took.

Thanks for last week's (and this week's) inputs on composites- especially your comments about composites and the V-22 on the last thread: in fact, this week's headline post discussion actually originated from your post- when I tried to compare the V-22 to helicopters of similar MTOW.

I was not seeking to condemn composites, but rather find evidence to justify their use. But regarding the specific example of the V-22, after some inconclusive attempts to "normalize" the data, I realized it was too difficult to compare a tilt-rotor composite aircraft, to a rotary-wing aluminum one.

So, as a second choice, I decided to compare fixed wing aircraft- and to make the comparison as valid as possible, I initially selected "adjacent" products (767-787-777) from the same manufacturer (Boeing).

The results of this surprised me- I had originally expected to find evidence of a weight-ratio advantage in the 787's favor, being the newest design.

The fact I did not, prompted me to expand the comparison, leading ultimately to the 169 models listed.

Which when fully explored, was as much about new design versus old, and light versus heavy MTOW, as it was about composite versus aluminum. (The fact the new, computer desinged airplanes, with some composites, don't seem to have superior weight ratios to old slide-rule designed airplanes without composites, is what really surprised- and disappointed- me).

And rather than seeking to condemn composites, I was seeking evidence to demonstrate their advantages (specifically, weight ratios).

I believe there are exciting advances in composite research every month, and it must be exciting to be involved with that. My expectations were that composites would result in lighter airplanes, especially brand new ones, especially when built by companies with the best computer modeling resources on the planet.

But so far- to my disappointment- that does not seem to be the case yet; so regrettably, I am "scaling back" my expectations- for now.

As far as extra margins of safety, wing tests require 150% load, for three seconds, regardless of the material. I am unaware of any extra margin of safety for composite versus aluminum. Manufacturer's can use extra material, for product liability concerns (although the wing tests, by all manufacturers, seem to demonstrate no such deliberate excess strength).

My argument is this: if I think a mixture of strawberry jam and diced rubber bands is a superior material, but an airplane must be built heavier to also include steel I-beams "just to be sure", then why bother- why not just use aluminum.

As far as an overly simplistic comparison, I can think of no better comparison than strength-to-weight of the finished product (rather than raw material).

Cost is also a valid metric- I appealed for manufacturing engineers to contact us with specifics, but so far, we don't have any numbers.

So why are manufacturers using composites? I'm still puzzled. Fatigue life? I think composites are superior- but really, how much more fatigue life does one want if a 50-year old aluminum DC-8 is still flying. Corrosion? I think composites are superior here too- but with modern coatings, corrosion doesn't seem to be too much of an issue- (sealing composites to protect them from humidity and UV will be an equal real-world issue, I believe). Weight savings? Doesn't look like it, unless really expensive analysis and manufacturing is used (such as for high-performance fighters).; January 5, 2010 at 11:59 PM
Phil Bell said...: cont'd:

The only item left that has not been dis-proven, is cost of assembly. Maybe it is cheaper to build-up (ply-up) composites, than rivet-up aluminum assemblies. Perhaps even more so, for complex shapes- as Soccer Dad mentions. (Again- I would like to ask manufacturing engineers to contact us with specifics).

And as SoccerDad notes: airframe manufacturers ARE using composites, and as an aviation enthusiast, I am trying to figure out why.

(And if they should be. Manufacturer's know better than us? I think that's what EAC proponents said too :)

The EAC proponents turned out to be -eventually- mostly correct about the technical details, and the blog turned out to be -eventually- mostly correct about the financial complications.

Ironically, perhaps in this case, the situation is reversed: we could be right about technical specifications, but wrong about the economics. Maybe composite's advantages might have more to do with the economics of parts fabrication, than the technical specifications- or costs- of the raw materials. (??); January 6, 2010 at 12:13 AM
Shane Price said...: Phil,

I've (very limited) experience with composite materials, going back 35 years. Specifically I worked on moulding competition kayaks (combining Kevlar and 'ordinary' glassfiber) to make the lightest possible boat.

Back then I bought one (which I still have) to experience the 'state of the art'. The basic design was 13'6" long, 22" wide (at the cockpit) and only 14" deep. It tapers in all three dimensions to each pointy end, and has a Kevlar hull and seat, with a 'chopped' fiber deck.

Total, all up weight?

18lbs.

This was a 'single use' boat designed and built for a European national team member and intended Olympic competition. It really only had to last one run down the slalom course, after which it could be thrown away. I was lucky enough to be ably to buy it instead.

I personally subjected it to 'destruction limits'. I did it again, and again, and again. I hit rocks, rolled it, deliberately sought out stoppers and generally abused it, intensively, over a period of a year.

It still floats, and I used it (for fun) only a couple of years ago. I weight a lot more now than I did all those years ago, but it still preformed as originally intended.

To give you an idea of what an improvement an 18lbs boat was, the 'standard' up to that point was 24lbs.

My point?

Even without the benefit of computers, basic design excellence and a sound approach to construction allows new materials to be introduced and used.

Success is not, however, assured in every case. The Olympian didn't win a medal, for the very simple reason that the 1976 games didn't included the event the boat was designed for...

Shane; January 6, 2010 at 2:46 AM
Beedriver said...: Composites are not unique in having a cost structure that is exponential relative to reducing weight and improving performance. Light weight aluminum structures are also very expensive requiring fancy machining of whole bulkheads from aluminum billets and chem milling to reduce weight where it is not necessary.

I remember when I was the chief engineer for Harken in the late 70's and designing ratchets,cleats travelers,big boat blocks, furling gear,etc that the fact that the exotic ball bearing material that I developed was 40 times as expensive as the previous material, was well worth the cost for the 2x to 4x load capacity that it produced.

I remember my parents light weight 45 lb 18 ft Kevlar canoe cost over $1000 in 1987 while the 75 lb aluminum competitor was only $300 and I bought a ABS canoe for $190 but it weighed 95 lbs.

thus if you need to win a race and money is no object or the operating costs of a lighter airplane outweigh the initial purchase cost' then going to exotic (expensive) production methods is worth it.; January 6, 2010 at 9:09 AM
gadfly said...: Beedriver . . . 'just looked at the Harken website . . . very impressive products. It's apparent that they are all about "quality" throughout.

gadfly; January 6, 2010 at 10:35 AM
Soccer Dad said...: Wow Phil, I'm not sure how to respond - you've compared EAC to Boeing, Airbus, Embraer, Hawker Beech and the other manufacturer's - one thing to note here Phil, they have delivered and are supporting aircraft, even aircraft that utilized composites, so I would think that there track record speaks for itself.

Funny that you would bring up the Comet as an example - poor engineering will always be poor engineering, irrespective of the materials utilized.

And yes, I do have a dog in this fight - I've been fighting the misconceptions and poor reputation of composites that were developed as a result of poor design and materials for practically my entire career. If you notice, the word fiberglass is seldom used in this arena - the word fiberglass brings up images of boats and old corvette fenders.

GAD:
There are techniques which are currently employed to "tie" the plies of material together. If you are interested in some of the approaches, you can take a look at z-axis reinforcements such as stitching or z pins and numerous other techniques. Funny that you bring up the tree comparison - I once interviewed for a position at one of the airframers and there chief engineer asked me to correlate composites and trees - answered the question, then I took a look at what they were doing and decided I didn't want any part of that airplane!; January 6, 2010 at 11:54 AM
Soccer Dad said...: Phil:
One other interesting tidbit about the FPJ. The tool was adamant about not utilizing composites because he felt that would overly complicate and make the aircraft too expensive. The only area where composites were initially used were for non-structural aerodynamic fairings. Guess that worked out pretty well.; January 6, 2010 at 12:07 PM
Baron95 said...: ATM Said...Nope. The new big engines are much lighter in terms of weight per pound of thrust.
----------------

You may want to compare within the same trust class and account for the weight of the structure to support the higher thrust engine if you don't.

Per pound of thrust a turbojet will always be lighter than a turbofan which will be lighter than a high-bypass turbofan. The advantages of the fans are in SFC, not weight.

But it's hard to compare, as no one is investing in modern turbojets.; January 6, 2010 at 12:30 PM
gadfly said...: Soccer Dad . . . Do you have any experience in tying layers together with aramid or Nylon fibers, etc.? My first use of Nylon (braided fishing line) inside epoxy was about 1959 . . . the Nylon provided "give", if the epoxy failed, yet prevented catastrophic failure. Later, while working on the "ramp" at ORD for United (to pay for my new family and continue school), I suggested that the corners of the fiberglas cargo containers for the DC-8 could benefit from similar re-enforcement.

(They would often crack and fail, right at the four "lift points". The DC-8 had a total of eleven containers, that would lift up into the belly of that great aircraft. My suggestion was rejected by the engineers back at San Francisco, UAL main facility . . . what did a ramp serviceman know about such things?!)

Much later, I had charge of certain major fiberglas projects, and somehow never got back to working with the Nylon re-enforcement, but even later had some hands on experience machining "aramid" (Kevlar) panels for armor plate testing for Sandia Labs, and making very large "curtains" of aramid cloth for the Airborne Laser Lab (with a big Adler industrial sewing machine . . . yes, I really can sew!)

It seems to me that for critical areas, a fiber such as "Kevlar", with just a slight amount of "give", combined with carbon fibers, would provide a large margin of safety in aircraft construction, while maintaining the benefits of the highly brittle carbon fiber.

gadfly

(The "curtains" for the cargo door on the Boeing C130 required large brass "zippers", to form a tunnel between aircraft and optical clean room mounted on a "food service truck". The joke going around amongst us was "How to make an elephant fly? . . . Start with an eight-foot long brass zipper!"); January 6, 2010 at 12:50 PM
gadfly said...: Correction: Within the past ten years, I designed and built (with my "crew") two small machines to impregnate carbon filament ribbons with Nylon (beginning as electro-static Nylon powder coated carbon fibers), and heat-bond the two into small ribbons . . . about 0.010" (inches, or 0.25mm, for our European readers) thick x 0.250" (6mm) wide . . . the second machine sheared the continuous ribbon into smaller ribbons, about 0.020" (0.5 mm) wide. The machines and technique were a complete success . . . the company for whom we did it turned out to be a "loser" . . . much talk but no "follow-through". We live and learn.

gadfly

(The old "Swede" is quoted as saying: "Too soon old, too late smart!" . . . So true!

The two machines? . . . part of our "show 'n tell" collection . . . rather impressive looking, come to think of it, each representing many innovations.); January 6, 2010 at 1:47 PM
airsafetyman said...: "The advantages of the fans are in SFC, not weight."

The advantages of a high-bypass turbofan are both the lower weight per pound of thrust and the lower specific fuel consumption. Certifying an engine for ETOPS adds very little, if any weight.; January 6, 2010 at 2:34 PM
gadfly said...: airsafetyman . . . And don't forget the restrictions of "noise level" in communities, such as Irvine, California, where aircraft must not exceed certain noise levels, during "approach" and "take-off", and climb out of "SNA" (John Wayne) like a homesick angel, out over the Pacific before taking a hard left. Yes, I speak as a novice . . . but not everything is about weight/thrust efficiencies. That's only the beginning of the problems . . . beginning there, it only gets more complicated. And, I suspect, these are the things of which the college professors don't have a clue, and many engineers fail to anticipate.

gadfly

(The "first" pleasure of Irvine, California, is enjoying a couple "Double-double-animal-style burgers, with coffee, fries, and vanilla shake at the "In-N-Out" on Campus Drive, across from the Irvine Campus, while watching the sun sink into the red western sky over the Pacific. The second pleasure is climbing out over the Pacific in an MD-80. Someday, soon, I'll top that when my Lord returns.); January 6, 2010 at 3:22 PM
Shane Price said...: Soccer Dad,

One other interesting tidbit about the FPJ. The tool was adamant...

Back in the good old days, when Vern Raburn pontificated about all those other 'dinosaur' GA companies who were afraid to innovate, the accepted term for him amongst us Critics was The Wedge.

Elevating him to the status 'tool' would imply an added degree of utility, which history has proved Vern lacked.

Please use the correct technical terms, so carefully evolved amongst us, in your otherwise most enjoyable contributions....

Shane; January 6, 2010 at 3:22 PM
gadfly said...: Wasn't there someone named "Skinny Dynamo", who had a '45 record back in the "fifties" . . . "Ain't that a Shane . . . My tears fell like rain!"

You Irishmen is the funniest people!

gadfly; January 6, 2010 at 3:31 PM
Baron95 said...: Sorry ASM - that is incorrect.

Lb for lb of thrust, a turbojet is much lighter than a turbofan. Not as fuel efficient, but much lighter.

The last turbojet engine designed for a western civilian plane, the Concorde's Olympus had a thrust to weight ratio of 5.4 - and that was over 4 decades ago - and that engine was designed to swallow air at M2.2+ at up to 60K ft.

Try that with your turbofan ;)

But, as you know, the SFC of the Olympus was 3 times worse than that of the CF6 on the 747, and the rest is history. I.e. we fly slower today than we flew in the 60s :(; January 6, 2010 at 3:46 PM
Shane Price said...: gadfly,

You Scots have managed to produce a few good comedians yourselves.

I hope your Hogmanay was as enjoyable as mine. There's nothing like the smell of gunpowder at midnight to help ring in the New Year.

Keep well in 2010, my trusty NM friend.

Shane; January 6, 2010 at 3:53 PM
Shane Price said...: References to gunpowder in my last comment might tend towards generating 'excitement' if misconstrued.

On New Years Eve in the Swiss alpine village where I habitually spend my annual skiing holiday, the local families compete to see who can procure (and ignite...) the largest number of the biggest fireworks available on the planet.

The fact that they do so with complete disregard for a) each other and b) any stray bystanders only adds to the excitement.

After all, if you're silly enough to ski off piste two and half miles up (in -35C...) then a few stray explosives going off in your immediate vicinity hardly increases the risk of injury, at all.

Shane; January 6, 2010 at 4:09 PM
gadfly said...: You Irish . . . now I'll need to look up what "Bobby Burns" had in mind in "Auld Lang Syne", etc.

Actually, I came across a Swedish holiday . . . January 13 . . . "St. Knut's Day", when the Swedes and other Scandihoovians throw out all the Christmas decorations, etc., and call it quits for another year. That's a holiday I can fully appreciate . . . except it should take place about the end of November.

gadfly

Ah yes! . . . me thinks I have found me "patron saint", if I were to have a patron saint. Did I tell you about the time I had a jack-o-lantern on the front porch at Christmas? Scrooge got bad press!; January 6, 2010 at 4:19 PM
gadfly said...: Shane . . . gunpowder, etc., . . . the other day, one of our grand-daughters, very slim and tall, 12 years old, got her first eight-point buck at about 150 yards . . . one shot, clean kill! Her dad had to settle for a six point buck. In our neck of the woods, this is called "shopping for groceries" . . . and that part is no joke!

gadfly

(But it's against the law to kill a wolf . . . go figure!); January 6, 2010 at 4:26 PM
gadfly said...: What was the subject . . . Lockheed? Well, for what it’s worth, take a look at this:

http://www.fark.com/cgi/vidplayer.pl?IDLink=4464984

They say, if you can walk away from the landing, you can claim success.

gadfly

(Composites? or titanium? . . . either way, this was an impressive little bird!); January 6, 2010 at 4:48 PM
airsafetyman said...: Baron, to repeat myself specific fuel consumption AND engine weight are primary concerns of engine manufacturers, supecreeded only by reliabilty concerns. In the early development of the RB-211, which has morphed into the Trent, Rolls Royce spent millions and millions of dollars trying, unsuccessfuly, to design composite fan blades to get the overall engine weight down.; January 6, 2010 at 5:47 PM
airsafetyman said...: "The last turbojet engine designed for a western civilian plane, the Concorde's Olympus had a thrust to weight ratio of 5.4 -"

Nope again. The maximum continuous thrust of the Rolls Olympus is 28,800 pounds of thrust with a 6,500 pound weight giving a thrust to weight ratio of 4.42 pounds of thrust per pound of engine weight. No where near the Rolls Royce Trent's 5.7 pounds of thrust per pound of engine weight at maximum continuous cruise.; January 6, 2010 at 6:03 PM
gadfly said...: airsafetyman . . . Before I forget, I'll make a prediction about the fan blades . . . even the compressor and turbine blades! The next generation may very well be with high-strength Japanese and/or American (Coors, etc.) ceramics, re-enforced with "whisker" fibers (saphire, etc.). This is not a new technology, but still in its infancy. This technology is already used in tool inserts in the machine trade (milling and turning), where high strength at high temperatures is already a common everyday problem.

Watch for it. And it may also be applied to "piston" engines, allowing much higher operating temperatures.

gadfly

(Don't get so caught up with the obvious uses of fiber re-enforced composites that you miss, maybe, the broader possible uses of same. There may come a time that ceramics make the transition from "micro" and "mezzo" to "macro", including major surfaces on aircraft. In the final days of the 1960's, we were testing similar materials in conjunction with the re-entry ablative heat shields for space vehicles. There are ways of making such components extremely light and strong.); January 6, 2010 at 6:14 PM
forest said...: Phil,

Thanks.

My nasty comment about composite: it can't hold a candle to unobtainium!; January 6, 2010 at 6:18 PM
Phil Bell said...: This comment has been removed by the author.; January 6, 2010 at 10:45 PM
Phil Bell said...: Hi Beedriver,
I've been trying to get caught up with last week's (and this week's!) posts- thank for your great posts about the Seabee, and about composites. (I greatly appreciate that you discern I am, indeed, just trying to make sense of it all).

And please extend warm thanks to your daughter, for consulting on the subject.; January 6, 2010 at 10:54 PM
Phil Bell said...: Hi Gadfly,
You hit the nail on the head with the ply inter-layer delamination concerns- I've talked to a structures guru- more on that ASAP (Julius had touched on it on the previous thread too).

(They are largely managable, but must be addressed with proper design considerations,but still- must be reckoned with).; January 6, 2010 at 11:00 PM
Phil Bell said...: Hi Baron,
Interesting point about higher cabin pressurization, and more humidity, for reduced passenger fatigue.

I'm not sure these are being used because it CAN be done (only with composites), or if it's a case of attempting to establish marketable distinctions (and could always have been done, if they would have wanted to).

Any ideas?; January 6, 2010 at 11:03 PM
Phil Bell said...: Hi ASM,
Thanks for the input on engine design criteria. -Good points.; January 6, 2010 at 11:05 PM
Phil Bell said...: Forest,
Thanks!
.); January 6, 2010 at 11:09 PM
Shane Price said...: Did another 'scrape' of www.controller.com to see what the boys in ABQ (or is that Chicago?) are up to.

The cheapest actual listed price is now just under one million dollars, but I'm pretty sure that anyone making an offer will start considerably below that number.

Turns out that of 27 total listings (4 of which are fractional) Eclipse Aerospace are offering 11.

Still the same 11 as the last time I checked, almost 3 months ago, and not one of them has a price attached.

When will this phoenix operation ever actually sell anything? I'm starting to get seriously worried about their survival, as even the deepest of pockets can't make a business out of spare parts (with the exception of the Phosterx canisters) and a few upgrades.

So I wandered over to their website (as you do) and discovered this .

Oh, how the mighty are fallen...

The basic message is, don't talk to us, contact the website. They clearly can't afford to hire a few CSR's to placate customers, or else they're afraid to answer the phone in case it's yet another lawyer, with yet another request for discovery...

Did anyone else notice how quickly the FPJ has vanished from GA journals? It failed to make any of the 'Top Ten's' I've seen that are so popular at this time of year.

I know one it would make it onto, and probably in first place:-

'Biggest Financial Crater in GA, Ever'

What do you think?

Shane
PS Sorry about that interruption to normal composite discussions. Please carry on...; January 7, 2010 at 4:16 AM
julius said...: Phil,

looking at the picture to your headline it seems that the weight didn't change inspite of all efforts. But which weight - fat mass, muscle mass... - increased or descrease?

The HBC Premier is said to have a light fuselage (45 kg?) - but the a/c is/was also noisy inside!

An increase of cabin pressure and humidity may not cause any structural problems but the air conditioning system has to deal with more water or condensate!

Julius; January 7, 2010 at 4:21 AM
Beedriver said...: The basic design problem with composites is that you are trying to make two very different materials work together. you do not need fibers even to have a composite, for instance, there are a number of plastics that are reinforced with clay particles that are composites.

For the fiber reinforced epoxy that is used on most airplanes, on one hand you have the reinforcement which is a fiber. very stiff in the order of 30 to 50,000,000 PSI for carbon, Kevlar, and spectra and strong up to 300,000 psi tensile strength glued together with a material which is weak, tensile strength of 10,000 to maybe 40,000 PSI and very flexible, in the order of a 100,000 PSI modulus, compounded by the fact that it is difficult to bond to many of the fibers especially Kevlar and Spectra.

some of the fibers, Kevlar and Spectra also have vastly different modulus in compression and tension, in the order of a factor of ten difference.

you can in general say that aluminum is aluminum however composites have at least 100 times the range of properties of any given metal and thus low performance cheap composites like Glass reinforced polyester (which makes good cheap boats) can give all composites a bad name if people view composites as all the same.

There is the same problem with the word plastics. as there is a huge variation in plastics and they can look identical. compare Tupperware to the cheap look alikes you find in the discount stores as an example. To work well you need to specify exactly the right material. Interestingly plastics can vary in properties not only because of the processing steps but even the crude oil that the plastics started from can cause a difference.

However the successful use and design of a material especially composites and plastics are very application dependent, thus we should not be pro or con for a particular material until the whole story is evaluated; January 7, 2010 at 7:40 AM
Baron95 said...: Phil Bell said....
Interesting point about higher cabin pressurization, and more humidity, for reduced passenger fatigue.
----------------------

Hi Phil. I'm far from very knowledgeable on this, but my understanding is that, while it is certainly possible to do this with aluminum, the penalties/costs are much higher.

The higher pressure differential would accelerate fatigue on the metal, but have a lower impact on composites. And the humidity is almost a non-issue on composite barrels and would have to be addressed for metal.

Another passenger advantage of the composite barrels seems to be the ease of locating the windows of larger size, again with reduced fatigue concerns around the window openings.

Are those meaningful advantages? Perhaps collectively, yes. The average Joe/Jane, probably could not tell it apart from an A330 or 777. But perhaps a frequent flier of long haul route could notice the difference and start biasing his bookings to the 787. An those frequent fliers are the money makers.

I, myself, will routinely book flights on a 777 vs a 767 or an 738 vs an MD80 on AA for obvious reasons.

When I fly to Asia, I'll book Cathay as an AA codeshare to fly on the 77Ws.

When the 787s are on these routes, I most likely will bias my bookings to it vs say an A340.; January 7, 2010 at 10:09 AM
Shane Price said...: I asked a question earlier in the thread, and Beedriver has just reminded me about the core problem I have with this 'new' material.

The effect of repairs on it, over time.

Over quite a number of months on Stan's original blog, there was a detailed discussion on the whole FSW issue. We covered the rational (high volume, with up to 4 birds a day) the marketing 'benefits', the cost reduction and a whole host of other topics.

I was really interested in how a repair to a FSW joint (or close to a joint) would pan out. My gut said badly, and it was one of the (minor) things that put me off the FPJ. But then I'll freely admit that I've next to no expertise with metals, so I let it slide. Plus there were many more problems with the FPJ than the way it was 'welded' together, a history we're all fully familiar with.

And then Beedriver talks about boats and it all comes (excuse the pun) flooding back to me.

Repairing those small composite canoes was a real challenge. It took lots of time, very carefully controlled conditions, a fair modicum of skill and lots of agility. Over a few years, i got quite good at it, but then hitting lots of rocks will force you to get good at fixing holes...

But the boat was never the same again. It didn't look right, it was inevitably a bit heavier, another blow to the same area generated an even bigger repair job etc etc.

On top of the repair problem you had the water ingress into the cracks. Some of these cracks were very fine, but water is a bugger for soaking into fibre. Then you either chill it or heat it, and the crack opens up a bit more, letting more in until eventually a condition we called osmosis set in.

I know that osmosis is the process itself, but what happens to the fibers is that they start to de laminate from the resin (the binding agent) that holds them together. Basically, a brand new hull would be semi transparent, and a damaged/repaired one with lots of 'osmosis' evident would go milky white.

Eventually, these milky white areas would join up, and the hull would lose the majority of its strength, in every direction. At that point, a boat was at risk of breaking up under stress, something that I personally witnessed on at least one occasion.

Not a big problem for a one man canoe in a river that was 25 meters wide, especially as you were fully protected with wetsuit, helmet and floatation aids.

But at FL410, doing 500kts?

I can hear the chorus of 'he has no idea what he's talking about' already. I'm sure the combined might of Boeing and Airbus are confident that they've overcome the issues, and I'm have to believe they are correct.

When the aircraft are new.

But in a number of years time, after a few repairs, followed by harsh winters and hot summers?

What then?

Shane; January 7, 2010 at 10:15 AM
Beedriver said...: repair is a big problem. ways have been developed to repair aircraft composites but it is a lot more procedure than grind it out, feather the edge and laminate on some more epoxy and graphite. There are systems out there that actually vacuum bag the prepeg on the location with all the fibers in the right direction and then heat the whole works up with a heating blanket to cure the epoxy. It must be done correctly and many times you cannot do it at all on a major structural area like a spar. Usually the result is also that the airplane gets heavier, much like putting a patch on an aluminum airplane.

Your canoe was probably room temperature cured (two part) epoxy with Kevlar reinforcement. Kevlar is particularly sensitive to water and if the matrix was epoxy (probably the lightest and strongest system easy to do for low cost) the Epoxy always had micro cracks from the time it was built. the best system, according to my brother who designed and built very high performance whitewater kayaks, was using a urethane matrix with the Kevlar, which was more flexible, did not develop cracks and was much tougher however slightly heavier than the epoxy Kevlar system.

By the way riveted on patches work on an aluminum airplanes because the skin is thick enough when it is first built to take the weakening caused by a row of rivet holes. this was how the skin was attached to the airplane in the first place. Things get much more difficult on skins that have been reduced in thickness away from the edge, to save weight (as I hear the skins on the EA500 were) as there is no extra aluminum to provide enough strength when you drill a line of holes in it to attach the patch.; January 7, 2010 at 11:50 AM
Shane Price said...: Beedriver,

We actually used infra red heating to raise the temperature, and reduce the humidity. It's Ireland we're talking about, after all. This was especially critical during repairs, as you really had to reduce the water content of the area to be repaired, otherwise the resin wouldn't bond to the hull at all.

You are correct about the epoxy resins we used. There were many grades of same, and we also used urethane as a 'gel coat' (first onto the female mould) which ended up on the outside skin of the canoe, for precisely the reasons you indicate.

However...

No matter how good your gel coat was, once the hull (or deck, for that matter) got the 'sharp rock treatment', cracks appeared. And cracks = 'osmosis'.

My current boat (somewhat larger than my Olympic canoe...) was also built using GRP, but is a little younger. Before I bought it, I had a proper survey done, and was delighted/surprised at a) the complete absence of any hull damage and b) the excellent overall condition of the gel coat. It's one of the principle reasons I bought it, which I did without the benefit of having seen it myself. I knew the exact specification I was looking for, located it through a trusted intermediary and the rest is plain sailing.

Literally...

So I see both sides of my own argument, from personal experience. My 35 year old canoe, while a little worse for wear, still functions. It wouldn't do so if I bashed up and down the Liffey for a season, but then it wasn't built to last in the first place. My 9 ton, 40' twin engined cruiser is a mere 30 years old and probably has the same number of years left in her.

But then she's lying up in a warm shed for the winter, and (more importantly) I've learned how to avoid the rocks...

Will composite airliners be kept in warm sheds during the winter months?

Can every commercial pilot avoid all the (metaphorical) rocks that repeated cycles are bound to put in the way?

When repairs are required, will they be a) carried out per instructions and b) effective?

I have my doubts. I think that, deep down, you share them.

Shane
PS Whitewater racing is a blast, but not quite as high tech as slalom....; January 7, 2010 at 12:33 PM
julius said...: Shane,

you are talking about the ramp accidents/incidents, tail strikes,,,

The insurance carrier will put some questions!
If a "light" bang with the gate bridge will cause difficult and time-consuming surveys of damage then the airliners will not be amused. But I think the airliners, FAA, and EADS will be aware of these handling issues and these points are tackled in the approved maintenace procedures.

What about a landing with landing gear up? Total loss in any case?

It's time to learn something about "aircraft" composites!

Julius; January 7, 2010 at 12:39 PM
gadfly said...: Shane . . . you’ve been exposed to the practical end of a common characteristic of most plastics: Plastics absorb water! . . . all of them. (A “Google” search will bring up countless papers/studies on water absorption of plastics and the effects on strength, etc.) Polyethylene and polypropylene are the exceptions, “almost”.* Thermo-plastics must be “dried” prior to injection molding. But even the thermo-set plastics absorb water, which can then “freeze”, expand, and begin micro-cracking, the same process that causes granite to de-compose over time. (The City of Albuquerque sits atop a huge pile of “de-composed granite” [called “D-G”], which was at one time the western portion of the Sandia Mountains which may have at one time been a mile higher than the present 10,000 feet.)

In the case of aircraft, any exposed surfaces of fiber reinforced plastic will absorb moisture, which tends to follow along the interface with the reinforcing fibers, freeze and expand, opening the area to greater tendency to more absorb more water through capillary action, and accelerate the degradation of the composite. In the case of aircraft, we immediately see the necessity for complete protection of all surfaces, inside and out, the dangers of “drilling or cutting” (exposing the fiber ends), and the importance of molding in the various fasteners for any and all attach points. Once the process begins, the “failed area” will only get worse, and is non-reversible . . . unlike the patches that can sometimes be made in aluminum skin.

Speaking of glass fibers: A study was conducted at Sandia National Labs a few years ago about the presence of water when a sheet of glass is “scratched” and under moderate stress. For reasons yet not fully understood, the water molecules cause the glass to crack at supersonic velocities. In the “old days”, glass cutters would often “spit” on the scribed lines, to obtain a clean break in the glass. Evidently they knew something, at least the practical application of water to glass. It could be that even at the micro level, water may accelerate cross fiber failure in the individual fibers. And my next question would be in relation to carbon . . . if a similar event could be observed. (I don’t know!)

Bottom line: “Metallurgy”, for the most part, is an old technology. But “plastics” are brand new, with little known before the nineteenth century. Plastic means “moldable or pliable”, and the marriage of metals and/or hard fibers to a “movable” substance opens up an entirely new field of understanding. So far, all areas of plastic manufacturing have only scratched the surface (pardon the allusions).

gadfly

* Polyethylene is “hydrophobic” . . . meaning that cracks in a polyethylene “chopping block” will trap bacteria, but the water used to clean the block will not reach the bacteria. Think twice about washing out a used “Ziploc” bag, to use a second time. You can wash it forever and never reach bacteria that may be in the small crack around the inside of the bag where it was heat-sealed. A wood chopping block is hygroscopic . . . water and salt will penetrate into the fibers and “kill” the bacteria. You see, you came here to study aircraft construction, and learned something you can apply in the kitchen, when you clean up after cooking a meal. Amazing!; January 7, 2010 at 12:40 PM
Beedriver said...: A piece of trivia from a dr. friend of mine.

25 years ago or so the powers that be decided that all the wood chopping blocks were unsanitary and would hold bacteria etc so in their wisdom they outlawed wooden chopping blocks and replaced them with plastic.

in a few years they discovered for the reasons sited above that the plastic was much worse. It turned out that the wooden chopping block was actually antibacterial and that wooden chopping blocks were much safer. (something about the fibers of the wood left sticking out of the end grain of the block actually killed bacteria) But by then the bureaucracy had decided so they never changed their decision. Once a bureaucracy decides there is no way to change the decision.

The end result is that my friend has a very beautiful large butcher chopping block in his kitchen he got for free; January 7, 2010 at 2:36 PM
gadfly said...: Beedriver . . . for that you get extra credit! May your tribe increase!

Earlier, there was some talk about “gel coats”, etc.

Somewhere, probably out at the “ranch”, there is a couple samples of our honeycomb panels, measuring 3 ½ inches thick by two feet wide and about ten feet long. The material is primarily glass “random chopped fiber mat” and polyester resin . . . 1/8th inch thick “skins” and a honeycomb of “glass rich” cells . . . weighing maybe four pounds per square foot. We used them for “ramps” while building our house . . . with a commercial size “wheel barrel” filled with sand and/or cement while building the basement . . . to cross over deep ditches with a free span of at least eight feet. Those panels were extremely strong, and light-weight, although I brought them home because they were “rejects”.

When we made them, we first applied a gel coat to the mold surface . . . the polyester resin was cured using a cobalt naphthenate accelerator and MEKP catalyst. Since that time, the gel coat has had no appreciable value . . . the sun and over three decades of New Mexico seasons have done their worst. The rough cut sides of the panels have been open to the elements for all those years, yet the panels retained great strength those many years. Since I don’t have the original data, and have no way of testing the panels today, I can only make a “value” judgement . . . and I am favorably impressed with the present strength of those panels. But given a choice, I would return to the tried and tested aluminum alloys of the past.

But, if we should choose to use fiber reinforced composites, I’ll return to the importance that we anticipated so long ago of the “cross fiber interface” between layers, and connecting components, to prevent de-lamination, etc., between adjoining features. To spell it out clearly: The interface, for instance, between the vertical cells (actually sinusoidal rather than hexagonal) and the two “skins”, included the intentionally rough and fuzzy fiber ends, to bond deeply into the two skins. We saw
“early on” the problems of “Hexcel” and others, in attempting to bond an inner core to the skins, and how easy it was to separate the skin from the core.

Gel coats are important, no question. But there are more critical features that will spell the difference between success and failure with this new wonder toy . . . fiber reinforced composites. In my opinion, there is far too much emphasis in attempting to make this new thing conform to “what we already know”, and not enough recognition that we have gone into an entirely new world, and all those old methods that are “tried and true” in metallurgy do not transition into the world of “fibers”, etc. In a strange way, we are returning to a technology of long ago . . . not as old as metallurgy (Read the first few chapters of Genesis and references to the early craftsmen . . . or to the older book of Job, Chapter 28 . . . speaking of mining for metals deep in the earth), and study the use of fiber-reinforced bricks in the time of Moses in Egypt. Although fiber reinforcement was, in a sense, “put on hold” for the past three millennia, we’re brought back to “square one”, and required to play “catch-up”, maybe re-learning an extremely old technology. Oh, by the way . . . “gel coats” have been around for at least three thousand years, and more. Gel coats do nothing to enhance strength, but prolong the ultimate demise of the basic material . . . and often make for a pretty surface.

gadfly; January 7, 2010 at 3:57 PM
gadfly said...: For some reason, there is a disagreement over the "character count" . . . Word Perfect says "3,600 characters" and the blog counts many over 4,000 . . . so this "tag-a-long-charlie" . . . to the last comments:

(Beedriver . . . the year was brand new 1956, and my electronics class wasn’t to start for three months . . . so I was assigned to the commissary “butcher shop” there on Treasure Island, boning “briskets” of beef, and learning how to cut and package various “cuts”, etc. At the end of each day, I had to “salt down” the big block of “hard Maple”, and scrape it . . . assuring that it was clean and sanitary. How could I possibly know that such things might someday apply to fiber reinforced plastics. Even putting the scraps through the machine and making “Swiss Steak” had a certain level of training that would one day apply to fiber-glas reinforced polyester panels. My wife still doesn’t understand that Swiss Steak is all the “junk” meat, made to look like “real steak”, but easy to chew through stuff that even our German Shepherd would otherwise find difficult to manage. Oh well!); January 7, 2010 at 3:59 PM
gadfly said...: Hey, y’all!

As a native of Southern California, I am a non-conformist by birth . . . at least in those ancient times. If I can get even one of you to think outside the box (as they say), I have achieved my goal. Don’t take anything for granted . . . but go to the source and think it through. My own heritage is filled with people that went against the grain of that which is comfortable . . . and the list is extremely long.

Some of you might move into new thinking concerning aircraft manufacturing . . . or maybe into some other new field. ‘Maybe you’ll simply provide a good product, and stand behind what you produce, fully responsible to provide full value to the customer/user. Now, wouldn’t that be a novel thing?!

Obviously some of you don’t have a “clue” about the technical stuff that some of us discuss. That’s OK! But there is a common thread that should by now be obvious . . . there have been many different aircraft enterprises discussed . . . some have shown excellent technology . . . and not succeeded. But those that have been less than honest with their customers, etc., have failed. Frankly, I’d much rather be among the “honest” and “straight forward”, and fail, than be among the other group that are sure to fail.

The bottom line is not so much about technology, but about transparent honesty, and fairness . . . with all concerned: That includes investors, customers, and right back home with the employees. It shouldn’t take (as they say) rocket science to have figured out the ultimate demise of Eclipse, early on. In a sense, they have fulfilled their promise of an “under a million dollar” jet . . . there’s a whole list of Eclipse jet owners ready to sell their precious possession for under a million. And if push comes to shove, I venture even “half a million” would be welcome.

Well . . . there you have the latest and greatest wisdom . . . or is it “whiz-dumb”, from the gadfly.

gadfly

(Last Sunday, I asked an “air traffic controller” out at “Double Eagle” about Eclipse traffic . . . he said, “Yeh, about three of four go in and out every week.” Somehow, that seems a far cry from the skies that were to be darkened with the little bird.); January 7, 2010 at 4:43 PM
Phil Bell said...: Hi SoccerDad,

Please don't take my surprising, and newfound, reluctance regarding composites personally- I'm not attacking you, and I very much appreciate your inputs.

(And my parody of composite phobia was meant in good humor, honest! :).

"Wow Phil, I'm not sure how to respond -"

Simple- help me find numbers for what composite airliner assemblies do better than aluminum airliner assemblies.

This really IS what I am trying to find with this investigation, and I've been disappointed, and frustrated, at how little I've been able to pin down. Many folks have made good suggestions, and I'd like help quantifying the results.

I'm not gripping about the material- I ready accept it has some dramatically superior characteristics (and some equally dramatically complicated implimentations).

(Shane provided a very interesting, and impressive one, for VLC's- Very Light Canoes. I have really tried to find one for :)

It sounds like you've been in the composite's industry for quite a while- if you can point me in the right direction, please drop me a line.

The same goes for anyone else who might have some helpful information pertinent to the benefits, or liabilities of composites, but is shy about posting directly. I like to think of our blog as a quest for knowledge and understanding.

aviationcritic@gmail.com

Thanks!; January 7, 2010 at 10:34 PM
Phil Bell said...: Boy howdy- reading today's comments was impressive!!

I felt like I was one of the overwhelmed group listening to how the "special glue for Post-its" was formulated (about 5:30-6:15 :)

(BeeDriver and Gadfly are smart inventors, but "I'm the one who thought of making them yellow"! ...And I'm "definitely cuter" too! :); January 7, 2010 at 11:01 PM
Shane Price said...: Legal Actions rebuffed, Snippet

SCHWARTZ v. iFREEDOM DIRECT CORPORATION

JEAN-GEORGE SCHWARTZ, Plaintiff,
v.
iFREEDOM DIRECT CORPORATION, f/k/a NEW FREEDOM MORTGAGE COMPANY, BRENT HANSEN and KEVIN GATES, Defendants.

No. CIV 09-0265 WDS/RLP.

United States District Court, D. New Mexico.

January 5, 2010.

In summary, the plaintiff had 'purchased' a position from the defendant, who in turn had gotten bored (or wised up) that EAC were unlikely to deliver the FPJ.

Needless to say, when the wheels and the wagon parted company, the 'new' position holder was not a happy bunny, and sued.

Check out the full judgement here.

But if your not bothered, the answer is:-

He lost...

Shane; January 8, 2010 at 8:41 AM
Baron95 said...: This comment has been removed by the author.; January 8, 2010 at 10:28 AM
Baron95 said...: Phil Bell said...
Simple- help me find numbers for what composite airliner assemblies do better than aluminum airliner assemblies.
---------------

Phil is that a serious question.

Lets look at the last new Airliner certified - the A380 - which has more composite content than any other airliner flying.

Airbus has patented a new joining process for producing the world's first ever carbon-fibre composite centre wing-box for a commercial aircraft. Some 25 per cent of the A380 structure is made of composites, generating a total weight saving of 15 tonnes, which contributes to its low fuel consumption and low noise emissions.

(http://www.airbus.com/en/presscentre/pressreleases/pressreleases_items/07_08_28_a380_380_patents.html)

So 15 tonnes or 33,000 lbs is the equivalent of an additional 165 pax (with bags).

So, according to Airbus, the use of composites enable them to carry an additional 165 paying pax on the A380.

And you think that is peanuts?

Composites are not a panacea, but their use is not in vain either.; January 8, 2010 at 10:31 AM
Baron95 said...: Yes Shane - is that any surprise?

He bought a "position". He got a "position". He didn't buy a plane. He didn't get a plane.

Next.; January 8, 2010 at 10:42 AM
Baron95 said...: And now, the contradictory picture of the new decade.

The wing of the most advanced composite airliner of the 21st century sporting a bunch of pieces of something that grandma uses to knit a sweater.

Can someone explain to me why the heck, after spending thousands of hours modeling on computer and testing on wind tunnels, Boeing had to take ZA001 out of the flight test line to outfit it with hundreds of pieces of yarn. That is right - grandma type yarn - to check on the airflow over the wing in flight.

Is there anything more bizarre?

(p.s. yes, I know Gadfly, will tell us why it is the best way to tune aerodynamic flow); January 8, 2010 at 1:23 PM
Baron95 said...: Now a contest to spice things up.

Today, a new piston twin received major agency certification (EASA in this case).

It will enter service in the US sometime this year flying folks from FL to the Caribbean (yep - international service).

A prize to the first member to correctly name that airplane ;) ;); January 8, 2010 at 1:30 PM
airsafetyman said...: "Can someone explain to me why the heck, after spending thousands of hours modeling on computer and testing on wind tunnels, Boeing had to take ZA001 out of the flight test line to outfit it with hundreds of pieces of yarn."

Obviously the computer modeling came up way short, apparently with the flaps and leading edge devices deployed. Remember the 727? It originally had an extreme final flap deflection setting. After a few airliners drove the landing gear through the wings on touchdown, Boeing decided to lock out the final flap setting on all models of the 727, even though it was certified otherwise. Seems common sense is in the driver's seat with the tufts?; January 8, 2010 at 1:37 PM
airsafetyman said...: Or maybe DayJet's Russian ant farmer computer whizes found work at Boeing?; January 8, 2010 at 1:40 PM
gadfly said...: baron

airsafetyman has saved me the trouble of being ridiculed for asking and attempting to answer what to some seems dumb questions. Thanks, safetyman! Your answer was precisely correct.

'Like Phil's honest questions, it's the few students in any class that ask the "dumb questions" that provide answers for the rest of the class.

gadfly; January 8, 2010 at 2:09 PM
gadfly said...: When the forecasters can predict the weather, correctly, three times in a row, I'll begin to believe computer simulation. Until then, I'll have a better forecast by looking at a piece of yarn nailed to a post out back.

gadfly

(Actually, it weren't yarn but a piece of rope left over after the horse done run off.); January 8, 2010 at 2:17 PM
Beedriver said...: Is it the new Dornier Seastar flying boat? good article in Jan flying and in Water flying the seaplane pilots association magazine. I saw it at Oshkosh.; January 8, 2010 at 2:43 PM
gadfly said...: Beechcraft Baron G58

gadfly; January 8, 2010 at 3:08 PM
julius said...: Baron95,

there are at least two "sky cars" -
it wasn't Moller's "Skycar" but simply
OMA SUD SPA from bella Italia!
(OMS SUD is also working for Boeing!)

Boeing had to take ZA001 out of the flight test line to outfit it with hundreds of pieces of yarn.

I rather would like to know what Boeing's PR force is saying to this picture! "That's standard..."

The dreamliner might become the best tested a/c before receiving the TC...

Julius

P.S.: EASA's TCs; January 8, 2010 at 3:19 PM
julius said...: Gadfly,

it is good practice to check models in real life ... computer models, too. Even Boeing had to learn the lesson(s)!

Someone in the blog said that stiff wings would be better for precise flying - what about landing a 787 in turbulent air with low fuel and max payload?
(Perhaps I will have a chance to experience it!)

Julius; January 8, 2010 at 3:40 PM
gadfly said...: julius . . . To underscore your comments:

Until major components can be automatically molded, the human element in fabrication will constantly guarantee unknown variations, and therefore about as easy to produce a computer model as to nail down all the variables of a “weather” model. It only takes a slight variation in procedure, from day to day, and person to person, to change the characteristics of an aircraft. And all the fancy quality assurance programs will do little to guarantee uniformity, and therefore empirical testing is not only “good”, but a “must”.

gadfly

(On a much smaller scale, Eclipse didn’t believe this . . . at least they didn’t appear to go much beyond their computer modeling and extrapolation, except when forced.); January 8, 2010 at 4:00 PM
Beedriver said...: As for the need of tufts on the 787. you always need to do actual testing to verify what the theory says.

Computers and fancy software are not better than the person using them if the engineer has no practical experience, he may design the best device but it will fail because the engineer did not really know what should come out of the software.

Computers may help an engineer design a product much faster than when he used a drafting board and a slide rule, however if the engineer does not understand in detail what he is designing all the computer does is allow him to make much bigger disasters faster. Computers allow engineers to destroy more money faster. they do not guarantee better results.

Interesting, That sounds familiar, wasn't the wedge a computer guy in a earlier life. maybe the computer enabled him to destroy more money faster than anyone previously.; January 8, 2010 at 5:38 PM
the Team said...: Beedriver, agree tufting is important. For those who may not know what a tufted wing in flight looks like go to Sport-Jet. Navigate to "Technical" then "Performance" and you see footage of their tufted wing in flight.

I hear Bornhofen is very attached to his sliderule.; January 8, 2010 at 6:48 PM
the Team said...: A while back some mentioned that EAI was sending nastygrams to independent shops indicating they were violating EAI rights by doing work on E500s. I recently talked to a local shop which consistently works on 3-5 planes. If they received a letter they seem to be ignoring it. Anyone know if all shops received letters and if there is any teeth behind it? Just curious.; January 8, 2010 at 6:53 PM
forest said...: Barry, good footage!

They must have done something right; two people walked away from the proto crash due to cabin design. Also, these guys haven’t scammed investors, refused to return deposits, produced unending hype, etc.

By the way, a non-conforming prototype is ok at this stage. They are selling experimental aircraft. [I don’t think they ever said they were yet building a conforming article.] Anyone know if Epic ever built a conforming article?

Baron may see this as cheerleading... but really, they've done quite a bit with so little. Imagine what could have been accomplished with more funding! I’m not sure underfunding is the issue (design expertise and integrity is), many still claim Eclipse and Adam were underfunded.

It’s an interesting story to follow. Who knows how it will end?; January 8, 2010 at 7:03 PM
julius said...: Beedriver,

as long as wind tunnels are needed (or used as they are faster in terms of getting results) there must be a final calibration of the computer model at full scale level.

Perhaps you will remember the Lauda Air accident over Thailand!

Even if the total drag figures are met in flight, it would be nice to know that the single drag figures are also met!
The yarn will visualise the airflow but not the pressure!

Julius

P.S.: The little C162 proved that the computer models are either to inacurate or too expensive resp. time consuming!; January 9, 2010 at 4:07 AM
Baron95 said...: Her Julius win the prize - It is indeed the plane from Italy.

As for the 787 using yard in its flight test program, all I can say is it is very sad.

Let me remind you, that the 787 is in full production. There are over 40 ship-sets in advanced stages in the supply chain.

It would be interest to know what Boeing will do if one of the yarns points to a wing redesign!!!

This is not 1960 when the 727 was designed. I'm probably holding more computing power in my hand (iPhone) then was available in the entire US in 1960. And Boeing has been designing high-lift devices for jetliners for 5 decades.

Very sad that they need the yarn.

Meanwhile, grandma is probably doing sweater layouts on her laptop.; January 9, 2010 at 9:23 AM
Baron95 said...: This comment has been removed by the author.; January 9, 2010 at 9:29 AM
Baron95 said...: Her Julius win the prize - It is indeed the plane from Italy.

As for the 787 using yard in its flight test program, all I can say is it is very sad.

Let me remind you, that the 787 is in full production. There are over 40 ship-sets in advanced stages in the supply chain.

It would be interest to know what Boeing will do if one of the yarns points to a wing redesign!!!

This is not 1960 when the 727 was designed. I'm probably holding more computing power in my hand (iPhone) then was available in the entire US in 1960. And Boeing has been designing high-lift devices for jetliners for 5 decades.

Very sad that they need the yarn.

Meanwhile, grandma is probably doing sweater layouts on her laptop.; January 9, 2010 at 9:30 AM
airtaximan said...: "As for the 787 using yard in its flight test program, all I can say is it is very sad."

I think its not sad, it great. The right tool for the job in fact.

It is SOP for validation.

Can be a good too to provide validation and calibration data tools which will can be used in quality control/inspection etc...

Just becasue its simple and used for many years does not make it "sad" or "bad".; January 9, 2010 at 12:58 PM
Shane Price said...: Gadfly,

(Actually, it weren't yarn but a piece of rope left over after the horse done run off.)

I think you're just being modest. I think you had The Wedge secured in your yard, and now he's escaped.

Should I be worried?

Don't think so, as Dublin Airport is mostly closed these days, due to a few centimeters of snow....

No, its' the rest of America that is right to be scared. After all, his last 'declared' project was the next big thing.

Nuclear power.

Once I heard that, I started digging a bunker. A very, very deep bunker.

Baron,

I think you were one of those who stated that my concerns about ongoing litigation as a likely fallout from the EAC mess were exaggerated.

I'm simply pointing out that the lawyers are making hay and, it would appear, will continue to do so. The effect on the 'new' Eclipse of these negative vibes can't be, how shall I put this, helpful. The details of each case are not really that important. It's simply that there are lots of them progressing through the courts, as predicted.

Couple that with the confusion over which spec does what and how much it will cost to move from one to the other and it's hard not to agree with the market. That would be the market that has not purchased ONE SINGLE aircraft in the past 4 months from the 'stock' of 11 that EA started out with.

4 months

No sales.

Not one, not at any price.

How long can Eclipse Aerospace last? Or, put another way, why have they lasted this long?

In contrast, Cessna continue to ship Mustangs and Embraer are flogging Phenom 100's. Both cost substantially more than what EA are rumored to be asking for the refurbished FPJ's.

Will all this ongoing litigation improve EA's prospects? How can not selling FPJ's, over such an extended period of time, make the business cash flow positive?

Am I missing something here? It this some new, magic method for building a company that America has invented and wants to keep secret from the rest of us?

Or are the owners club simply deluding themselves, like they did when they fell for The Wedges' snake oil treatment in the first place.

I know what I think.

Where do you stand?

Shane; January 9, 2010 at 2:23 PM
jet_fumes said...: Tufts.

As ATman says, it is the right tool for the job.

CFD is still just as effective at predicting boundary layers as predicting weather five days ahead.

When we will have accurate weather forecast for next month, tufts will disappear from aircraft prototypes.

Nowadays tufts ask for just a few vortex generators to be tamed.

Sometimes none are needed, but you still need to check.; January 9, 2010 at 2:26 PM
Anonymous said...: Barry they were going after anyone with a website that had ANY eac originated pictures or so called IP. Not a big deal but the lawyers will always suck cash from EAI. They must be a great client for now. I would hope that the shop you speak of continues to prosper. Eai makes a big deal of the Global training but honestly there are many a&p techs that worked the eac service centers that know far more about the jet than some of the officialy trained. Take a tech that went from manufacturing and worked through the line and ended up in a service center because he or she held an a&p but didn't get the global cert because they were too busy working the squawks. They know the thing in and out but need to get the cert otherwise they're not legal. This is NOT to say there are some super techs that have the cert and are working for eai. They have some of the best ex eac techs to be sure. Very understandable though when it comes to FARs. I'd like to know if the dayjet plane with a repair to a chem milled fuselage panel is documented. It was damaged during a wind storm when a flock was packed tight outside at abq. Simple doubler repair but nonetheless....; January 9, 2010 at 8:22 PM
Baron95 said...: Jet_fumes said....tufts will disappear from aircraft prototypes.
-------------------

That is just it. These are NOT prototypes. These are full production articles. They were supposed to enter service - now we hear the first 4 will be scrapped. But 36 others are already in advanced assembly process.

These are low speed (under 150 kts tests) - the time for yarn was in wind tunnels 4 years ago.

But hey - give that this is the 787 - a program that has had 4 different leaders, a program that produced flying articles so heavy and so full of patches that the first 4 will be scrapped and the first 20 will be severely over weight, a program that is 2 years late and counting, a program that has paid and will pay billions of dollars in penalties and interim lift, then, I guess the yarn fits right in.

I hear they will be fitting some yarn on the F35 as well next week. But given that it is the military, it will be a $500,000 MIL spec piece of yarn. It will be used to calibrate the aileron deflection at high alpha when roll rates exceed 200 degrees per second.

The yarn also has a special anti-radiation coating, to maintain stealth in case the yarn needs to be retained in production birds as a slip-skid indicator.

Progress.; January 10, 2010 at 9:34 AM
flightwriter said...: Speaking of "progress," there's quite an interesting read over on the Eclipse 500 Owners Club site. In .pdf form:

Eclipse 500 EFIS 1.5 & Flight into Known Icing

The writer seems resigned to the "this is as good as it gets" mentality, and disgust with the whole situation comes through in parts. Notes about not being able to distinguish runway markings through the heated windscreens aren't especially inspiring, either.; January 10, 2010 at 12:14 PM
Baron95 said...: A few more GA updates....

It looks like Embraer in fact met its prediction of Phenom 300 deliveries before the end of 2009, and in fact delivered a Phenom 300 on Dec 29 to a US-based fractional operator.

It also looks like Cessna finally got an order for a Citation Frankenstein (err. Soverign - yep the one a fuselage from one jet, wings from another, etc). As a result, the are recalling 180 workers out of the 8,000+ that were laid off to restart that "line".

I think, that is the first substantial GA re-hiring of the new decade. Hope things continue to improve from there.

Things look better than in airline world, where the 787-3 is now probably dead for good (ANA canceled the last remaining orders) and the CRJ-1000 continues to be grounded since they can't get the ruder to turn in the right direction - I hear they'll put some software yarn to patch it up.; January 10, 2010 at 12:55 PM
Baron95 said...: Thanks for the news Stuck in NM.

With FIKI + Avio NG 1.5 plus the new tires all approved and being delivered, it looks like the utility and value of the airplane will slowly increase.; January 10, 2010 at 1:11 PM
julius said...: baron95,

With FIKI + Avio NG 1.5 plus the new tires all approved and being delivered, it looks like the utility and value of the airplane will slowly increase

- but only for the current owners!

Potential new customers might be a little astonished about this type of "progress" or " integrated avionic system".

Julius

P. S: The Phenom 300 also has some FIKI limitations: Max FL with FIKI is FL300 (because of the engines!).; January 10, 2010 at 2:14 PM
Shane Price said...: Baron,

With FIKI + Avio NG 1.5 plus the new tires all approved and being delivered, it looks like the utility and value of the airplane will slowly increase.

While the value of the company supporting the aircraft slowly sinks below zero....

Some people will never get it. This is a dead parrot, and nothing, but nothing will revive it now. There was a small window of opportunity during the Chapter 11/7 mess, but the hubris of a few prevented a logical outcome.

Methinks the 787 is also in real trouble. The so called 'long and thin' route model looks ever more difficult to justify in an era when full body scanners and the rest of that stuff may deter people from air travel.

I chose to drive to the Alps this year, rather than fly, which is pretty sad as I used to enjoy the process so much. I get the feeling, amongst my peers, that I'm not alone in getting fed up with the hassle.

Shane; January 10, 2010 at 2:30 PM
flightwriter said...: I don't see progress per se, Baron... I see many, many kludged "fixes" patched onto a subpar airframe, that when working properly all at once make the plane just capable enough to fly in inclement conditions.

And while the Eclipse pilot group (and the Eclipse training program) deserves credit for avoiding significant accidents thus far flying their cobbled-together planes, "more capabilities" equals in my mind little more than "more opportunities for the plane to fail those pilots at the worst time possible."

I do hope I am wrong.; January 10, 2010 at 2:42 PM
Anonymous said...: StuckinNMs link is interesting. Mentioned is Mr Neild who is a great tech and individual as well. Mr Neild was in ABQ last year and saw first hand the incompitent (when they would even venture to the service center since they seemed to be afraid of the cold) engineering support available to come up with a repeatable windshield coating solution. I was personaly embarrased. A tech used isopropyl to clean a coated windsheild and ruined it. At least it allowed for a partial recoat fix. Pretty sure it was approved as a repair. There was one jet that engineering left the heat lamps on and utterly destroyed a windshield. Looked like a close call with a sidewinder! I can recommend any owner that reads this blog to contact Mr Neild before doing anything that they have serious questions about.; January 10, 2010 at 3:50 PM
Baron95 said...: Sorry guys, I fail to see how more EA500s flying with FIKI and Avio 1.5 and new tires is worse than before.

Sure it is not great. It is not even good. But it is at least less bad.

I disagree that the increased capability will lead to an increased accident rate. Area Nav, full autopilot and terrain awareness can only contribute to increased safety.; January 10, 2010 at 6:19 PM
Phil Bell said...: New post will be up Tuesday AM- sorry for the delay.

(Over the past couple of months, I've had increasing difficulty posting "headlines" on Sunday night. I use wireless broadband most of the time- it works great 10% of the time (hit 700K-1 Mbit/sec), okay 70% of the time (200-400 Kbit/sec), poorly 10% of the time (20-100K Kbit/sec), and wretchedly the remaining 10% of the time (0-20 Kbit/sec).

I have attributed (perhaps erroneously) the erraticness to how busy the cell phone networks are- and figured Sunday nights, everyone is calling family and friends. Which seemed a little odd, because I have never had a problem with cell phones on Sunday night. Well, 2+2...I realized it's Google Blogger that is "blogged down", so to speak, on Sunday night, at least for putting up new threads.

So, catch 'ya Tuesday AM.

(Thanks for the many great posts this past week- there are a plethoria of questions and responses to get caught up with!); January 10, 2010 at 8:05 PM
Floating Cloud said...: Shane:

Not sure if you were following blog whilst on skiing holiday in the Alps, but my post on December 29th questioned the business “deal” between the city of Albuquerque and Eclipse Aerospace that involved “trading” a building at Double Eagle Airport for free rent at the Sunport site. (I was snow bound in Colorado at the time with my Mother -- ah yes, Christmas in the Rockies.)

Airsafeteyman was the only one to agree with me, and further questioned if the building was worth so much than why did Eclipse Aerospace not sell the building and pay the rent to the city?

All in all, in my viewpoint, it would seem to bode quite poorly for Eclipse Aerospace here in ABQ…. Are they trying to pull Grandma’s yarn er -- wool over the city’s eyes?

The “deal” was supposed to go on the agenda of the City Council well over a week ago and rien, nada, nix has happened – at least within the public domain. Who knows what goes on behind closed doors in New Mexico? Are we a US State, really?

Gentlemen:
In the mean time I am grateful, to all of you for your insights into composite materials. Even with my basic understanding of material sciences in the arts, and with or without grandma’s yarn, the 787 is no where near ready to take a chance on human life. In the future it will most likely succeed – but, unlike what the artist may do while making their creations they may tank, but the whole supporting cast/crew and those along for the ride do not need to go down (literally) with them. The day for composites will come and I for one will be especially glad if it will help with jet lag! Waiting with anticipation for that day...

Floating Cloud; January 10, 2010 at 8:22 PM
Phil Bell said...: Hello Shane,
I hope your trip to (and from?) the Alps was safe, and the stay while there enjoyable!

I am not sure what to think of EAC- things sure have changed a lot over the past 12 months. (unfortunately, it's been pretty rough for everyone else in the business too...Let's hope 2010 is a better year for everyone!)

I'm not too surprised the Delayjet planes are still, er, delayed. I figure there's a plethora (ahem:) of other used Eclipsi on the market.

Hopefully, it will be a good year for aerospace- and publishing ! :); January 10, 2010 at 9:09 PM
Phil Bell said...: Hi Baron,
Thanks for the tip on the piston-twin from Europe- congrats to Julius for being aware of it- I hadn't heard of it before, but it looks like a nice plane- hope to see a flight test in the major mags sometime soon...; January 10, 2010 at 9:12 PM
Phil Bell said...: Hi Floating_Cloud,
It sounds like your Christmas vacation was equally scenic- best wishes for a safe return as well.

I hope I did not shade composites as intrinsically unsafe- my comments to SoccerDad were tongue-in-cheek. I think there are some safety issues (notably, lightning strikes, and flammability), but I have reasonable confidence that they will be addressed, and I would expect the 787 to be as safe as the 777. One *could* argue that composites, with superior fatigue characteristics, and corrosion resistance, result in a safer airframe.

I for one, am not ready to say that- yet, anyway. But compared to the jump to fly-by-wire with the 777, I would say the jump to composites (with fly-by-wire) is somewhat less dramatic/(disruptive:).

It will be up to Boeing to instill some confidence in the flying public (and investors) eyes though, with a timely and successful flight test program. Good luck to them!

(On second though, I hope there is no luck involved- I hope everything that could go wrong, does go wrong*, so they can fix it before it enters service. So far, I think they pretty much figured out how to make everything go wrong with the design / procurement / assembly phase).

(*That is NOT ill-will towards the program: in fact- exactly the opposite. Part of a good test program, on the ground and in the air, is to find problems 9and fix them) before the customer and public experiences it. I have confidence Boeing will give it a good "wring out" -they have one of the best flight test organizations in the world, and entry into service should be safe and trouble-free).; January 10, 2010 at 9:22 PM
Turboprop_pilot said...: Just received this from Linear Air:

"Jet Away to the Bahamas with Linear Air

With cold temperatures sweeping across the country there has never been a better time to get away to the beautiful islands of the Bahamas.

Whether you stay for a weekend or longer, Linear Air will pick you up at an airport close to your home and get you to the islands commercial service can't. Fly on your time, not theirs and avoid long security delays.

Aboard Linear Air's Eclipse 500 jet, you'll experience the jet set style at a fraction of the cost. With one way pricing from Boston and New York under $9,900 making it to the Bahamas has never been this easy!

Contact our customer service team today to discuss pricing for your Bahamian getaway. Email customerservice@linearair.com or call 877-2-LINEAR x2 (877-254-6327 x2)."

I haven't called them but I thought the plane hasn't been flying. I wonder if it has been upgraded to FIKI?

ex Turboprop_pilot; January 11, 2010 at 8:04 AM
Floating Cloud said...: Dear Phil:

Mais non, mon amie! Ce n'est pas votre faute!

In this fascinating discussion about materials, which you began Oh Blog Miester, I don't think anyone on the blog was 100 percent ready to get on board with composites -- yet! It will happen but not before Boeing is truely ready. I hope!

In the mean time, I found it most interesting that Baron picks and chooses specific airplanes on commercial flights (when needed) for environmental comfort. What is the physiology of jet-lag for human beings? Presure? Humidity? Too many alchoholic drinks? Not enough alcoholic drinks? Steerage vs 1st class -- done it all from Asia and Europe to the US and still come out lagged upon my return home but not on the out bound?

Truely stymied,
Floating Cloud; January 11, 2010 at 8:52 AM
Baron95 said...: Phil Bell said...
Hi Baron,
Thanks for the tip on the piston-twin from Europe- congrats
--------------------------

Phil, what was the last new type FAR/EASA-part 23 plane certified as an US design by an US OEM?

Was it the Mustang and Eclipse?

What was the last piston twin? Was it the Mojave back in 84? (I'm discounting the Adam-500 here as it was a failed attempt and never reached full IFR/FIKI certification before it died).

What was the last piston single? Was that the Cirrus and Columbia?

I can't even remember anymore.

I'm talking about really new types here, not type amendments.

Catch my drift?

In the meantime multiple new piston singles and twins (e.g. DA42, Sud) are coming from Europe and jets from Brazil.

I still don't know what further evidence you guys need that the US is falling way behind in part 23 and in particular piston part 23.

That was my whole point in posting about the SUD.; January 11, 2010 at 10:14 AM
Baron95 said...: Phil Bell said...It will be up to Boeing to instill some confidence in the flying public
------------------

Seriously? Do you think the flying public knows what kind of twin jetliner they are in, let alone the nuances of construction techniques?

99%+ of fliers have no clue if they are in an A330 or 767 or 777. They certainly have no idea what engines are on the wings, and few even know who is operating the plane on a code share flight.

I doubt very much Boeing will "instill confidence" in the flying public as it relates to the 787.

What they and their customers (the airlines and leasing companies) will do is stress the lower fares (and perhaps the better air environment) that the 787 will allow.

Safety WILL NEVER EVER BE MENTIONED to the "flying public".; January 11, 2010 at 11:08 AM
Baron95 said...: Floating Cloud said...I found it most interesting that Baron picks and chooses specific airplanes on commercial flights (when needed) for environmental comfort.
------------------------

Its not so much for environmental comfort. It is for ease of upgrading, in-flight services (e.g. video on demand and internet access), large baggage bins for fast boarding and space, number of isles, number of premium seats and class of service (for ease of upgrading), etc.

Example, I can fly to MEX on an A319 Mexicana-operated code share with AA. That plane has large bins that fit all the roll-on wheels first on both sides, VOD, lots of first class seats (for upgrading), wide isles, wider seats. The FAs are generally young, energetic, motivated, fit, pleasant.

OR

I can fly on a decrepit, smelly, AA DC-9 (er MD80). That is a VERY LOOOOONNNNNG tube, with narrow seats and isles, only fits roll-ons wheels first on one side - it is a nightmare to board - takes fully twice as long. It has no video at all - not only a drop down TV, let alone AVOD. The trim is falling apart. If you are unfortunate enough to sit in the last 10 rows, the noise of the engines (inches away from your face, will be deafening, and lets not talk about the wonderful personal appearance and demeanor of the 55 year old AA FAs.

So, yep - I pick A319 vs MD80 every time.

Same deal going over the Atlantic. I pick a BA777 vs an AA 767or 757 (soon).

To Asia, I want to be on 77Ws or A380s from SQ, CX, etc.

You bet I pick the plane and the operator. But not for environmental reasons.

Would I pick an AA 787 over a 767? YES. Will I pick it over a CX 77W? I don't know yet - lets see how AA configures it.

My priority for booking is:
1 - AA or One World carrier - for miles.
2 - The factors above.
3 - Price (only determinant if it is more than a few hundred bucks difference), typically not an issue.

But the "flying public" books based on price, then price, then price, than loyalty program, then schedule, then carrier, then airport,... Few if any book based on plane.; January 11, 2010 at 11:26 AM
Floating Cloud said...: Baron:

Guess I misunderstood your comment, with all the talk about window sizes, air quality, and airplane construction! Nevertheless, good to know some of your suggestions for better airplane comfort. After reading this blog for since March of last year I am one of the few people in the public sphere who now does think about the airplane (and safety) itself. Could be a curse too!;)

In the mean time, I will take special note of "Baron's Best of Airplanes Picks." Is there a book here?

I was also happy and surprised to see that you like specific airplanes on Mexicana Airlines. It's been one of my favorite airlines for years. With all the work I used to do in Mexico sometimes flying there every six weeks I found Mexicana to be quite pleasent -- staff, space, even the food was decent or at least it used to be....

Thanks!
Floating Cloud; January 11, 2010 at 3:24 PM
airtaximan said...: while you all contemplate your navels, thinking about eclipse-BS long gone... there are real developments within the markets Vern tried to play in, and lost BIG TIME.

Acquasitions abound in GA... airlines buying charter companies... there's a fleet brewing with around 100 real biz jets (no VLJs mind you) in GA providing taxi service at real affordable prices.. and new models as well like cogojet and flygreenjets.com... not jet models, but BUSINESS models... taking root.

You won't find them from the shore to Martha's Vinyard, though... that's too small amarket. Try NY-LA or NY-Chicago or NY-Florida... the MV route requires cape air, with their props... which are in fact the right craft for the job... unless your ego demands a jet...

The baron's are lost perfecting buggy whips and complaining about old companies inability to adjust, while the oldest biz models... such as the airlnes... invest and reinvent themselves with new business models to provide service levels only once dreamed of on the airlines... and now are becoming a reality for everyday travelers via business jets. YES, OLD FASHINED BUSINESS JETS....

A lot of this stuff is going on, while the complainers just complain.... look in all the right places, stop bitching and look hard at the real progress... you will awake TODAY and notice a strong revival for GA, again NOT based opn BS craft promises, but real proven jets... my advice FWIW.; January 11, 2010 at 4:00 PM
airsafetyman said...: "the MV route requires cape air, with their props... which are in fact the right craft for the job..."

Cape Air really, really, really needs to deep six the worn out Cessna 402s and go to something like the the Saab 340s or deHavilland Dash 8s - at least.; January 11, 2010 at 4:57 PM
Floating Cloud said...: You are a good man, Air Safety Man.; January 11, 2010 at 8:01 PM
Phil Bell said...: Hi Baron,
"what was the last new type FAR/EASA-part 23 plane certified as an US design by an US OEM? Was it the Mustang and Eclipse?"

Sounds good to me.

"I still don't know what further evidence you guys need that the US is falling way behind in part 23 and in particular piston part 23."

Hmmm. I think the SUD is a nice airplane. Whether it outperforms, or outsells, any of the 30-40 year old designs in the US remains to be seen though. I wouldn't discount lack of inventiveness here- gobs of activity during the VLJ craze. No money in anything smaller. (In fact, not much money in anything the same size).

"What they and their customers (the airlines and leasing companies) will do is stress the lower fares (and perhaps the better air environment) that the 787 will allow."

I think they'll push the lighting control, overhead bins, and entertainment systems. And air quality too. And maybe smoother ride with flexy wings.

"Seriously? Do you think the flying public knows what kind of twin jetliner they are in, let alone the nuances of construction techniques?"

I think when they look out the window and see the wing flapping, they will.

"Safety WILL NEVER EVER BE MENTIONED to the "flying public"."

I agree, the airlines don't benefit from saying "Fly With Us- Our Planes Crash Less Often!"

But there was great effort expended to make sure people knew they were NOT flying on DC-10's.

DC-10 post-Chicago ramifications; January 11, 2010 at 9:09 PM
Phil Bell said...: New headline delayed another day due to work- will be up Wednesay AM- sorry for the delay.; January 11, 2010 at 9:10 PM
Baron95 said...: Phil Bell said...But there was great effort expended to make sure people knew they were NOT flying on DC-10's
----------------------------

Please - The DC-10 is an unfortunate airliner - with I think 3-dozen or so hull losses. By comparison, the 777 fleet has flown more passenger miles with only the recent LHR hull loss. The DC-10 has killed over 1,000 of its customers, the 777 none.

It is a different world.

If any widebody airliner today started falling out of the sky in the numbers the DC-10 displayed, it would be a monumental event.

Having said that, the flying public continued to fly on DC-10s and MD-11s until the 777 and A330 put them out of business along with the L-1011.; January 11, 2010 at 10:25 PM
airtaximan said...: ahh, yes, ASman... the right prop for the job might indeed be diferent than the 402s... you are correct.

Just not a jet, which is my point.

Thanks; January 12, 2010 at 6:59 PM
gadfly said...: Shane said... Some people will never get it. This is a dead parrot, and nothing, but nothing will revive it now. There was a small window of opportunity during the Chapter 11/7 mess, but the hubris of a few prevented a logical outcome.

Shane, that fact that you still can't post without taking another poke at the expired Eclipse or the existing Eclipse is proof that it is not yet dead. Deal with it.; January 13, 2010 at 6:07 AM
Shane Price said...: Plain Truth,

I post, quite a bit, about other subjects. On this thread alone I've commented on my experience (limited, but practical) with composite canoes, the weight effects of added facilities in modern airliners, the correct name for Vern Raburn, risk management on ski slopes where the locals dish out gunpowder like snuff at a wake and sundry other matters.

But....

It's still a dead parrot. It's not asleep and it's not resting. The only reason it's still going is some of the misguided owners, who've 'nailed' it to its perch.

Sooner or later someone, somewhere is going to point this out. It might be a bank, it could be the FAA, or possibly disgruntled suppliers. There could even be an sudden influx of common sense at Eclipse Aerospace.

I personally think the latter is unlikely, but then Fox News thinks Sarah Palin will 'add weight' to its commentary team, so anything is possible.

So, thanks for the opportunity to clarify my position on this matter. Anytime it tickles your fancy, feel free to post another, similarly ill informed comment.

Shane; January 13, 2010 at 6:47 AM
airsafetyman said...: "the right prop for the job might indeed be diferent than the 402s..."

I am just concerned that if they keep flogging those worn-out 402s on their routes they will have a
"Chalk Airlines moment". They have already come as close as you can get to a main spar failure and escaped once.; January 13, 2010 at 2:07 PM
Baron95 said...: Shane said...but then Fox News thinks Sarah Palin will 'add weight' to its commentary team
-------------

Shane, that is naughty of you to insinuate that Sarah Palin is fat.

For the record, I think she is *hot*. ;); January 13, 2010 at 2:26 PM
Baron95 said...: Shane said...Methinks the 787 is also in real trouble. The so called 'long and thin' route model looks ever more difficult to justify in an era when full body scanners
----------------

Well, I think full body scanners will have many positive effects. Like people may decide to lose some weight and women will decide to wear prettier underwear to travel. Plus, just think about how much fun it will be when the scanners come down in price and are installed at the mall and movie theater.

As to your concern about the 787 and long and thin, I think you are misguided. Air travel will continue to increase - just think about what will happen when the other 2B Chinese and Indians can afford air travel. There will be more destinations and more routes. And the more airport hassle there is, the more people will want to fly direct.

You should be worried about the A380. Airbus began 2009 with a goal of delivering 18 A380s, before dropping the target to 14 after some airlines asked to defer. In the end, the planemaker only managed to hand over 10.

Tom Elders, Airbus CEO, just said on the press conference yesterday that “The A380 will still be a financial liability of the company for years to come,” “I’m not happy with the cost situation, it needs significant improvement."

Planned deliveries were 80% higher than actual deliveries and reading Elders comments, it seems like every plane is being delivered at a loss, even after all the billions that were previously written off.

Not a good situation for Airbus.; January 13, 2010 at 3:22 PM
Baron95 said...: Oh, and speaking about their A350, he said... "Airbus encountered some “challenges” dealing with composite wings and fuselage, including systems installation and incorporating lightening strike protection, a requirement for planes built with composites instead of aluminum.

Combine that with the CFO's revelation that Airbus had used the A350 schedule buffer and the fact that the A358 will now be a heavy straight shrink from the A359, and the stage is set for some pain at Airbus new composite twin jetliner.; January 13, 2010 at 3:25 PM
Baron95 said...: And Phil, too bad your A400 thread is dormant. Despite first flight, the real news is what has transpired in the past couple of weeks and revealed on the Airbus conf call.

According to Airbus, they are burning through $100M Euros/month on the A400 and that is unsustainable. Airbus had made loss provisions of $2.4B Euros on the project. The member countries can cancel all orders outright, due to Airbus delays on the A400.

Elders said yesterday, "In its current form, the A400M program puts all of Airbus in jeopardy"; January 13, 2010 at 3:30 PM
Baron95 said...: Hey Phil ---- How about doing a story on gross negligence and cover up by professional flight crews and their unions?

We can start with Delta 188, where after being out of ATC radio contact and ignoring multiple ACARS messages, DL 188 pilots and Delta's chief pilot apparently engaged in a concerted effort to delete evidence from investigators.

Among their actions:

1 - DL188 Co-Pilot, when he should be concentrating in correcting their mistake and landing safely and without further incident, decided to engage in erasing at least 8 ACARS messages "Call ATC", "ATC looking for you", etc.

2 - Delta Assistant Chief Pilot, boards the plane after landing, and contrary to SOP does not pull the CVR CB. Instead, He or DL188 crew or other Delta union personnel, proceed to turn on power to the plane at 10PM, 11PM and 2AM, for no apparent reason, each time managing to erase 5 min of the 30min CVR tape.

3 - Mysteriously, all the flight documents, including flight plan, which both the chief pilot and the crew should have retained per SOP on an incident, also vanished.

And then there are their excuses for the above action to the NTSB - real gems:

"While we never want to interfere with the duties of other agencies, this delay prevents the CVR circuit breakers from being pulled in a timely fashion and in this case, it was at least a causal factor in the flight documents being gathered,"

HAHAHA LEOs left the scene shortly after the landing once terrorism was ruled out (it was never really suspected after the crew contacted ATC). The powering of the plane repeatedly after that, many hours after LEOs left was nothing but a deliberate attempt to erase as much of the CVR as possible.

"I don't know if the crew retained [the paperwork] or due to their distraught state discarded them as we normally do on domestic, uneventful flights."

Hahaha - SOP - after an incident, preserve and secure all available data. Was the Chief pilot also distraught and forgot his basic duties to pull the CVR CB and collect the flight docs? Please!!!!

The [first officer] said he inadvertently pushed the 'delete all' button which erased all the messages." Yes, right!!!!

This is shameful. These guys should never fly so much as a Piper Cub again. And the assistant Chief Pilot should be fired if not charged with interfering with a Federal Accident Investigation.

I'm totally against bringing LEO into accident/incident investigations, but in this case, there may be post incident criminal activity. I want that to be investigated.

Not the incident. The post incident cover-up.

Shame on DL188 crew and the Assistant Chief Pilot.

I hope the mainstream press picks up on this.; January 13, 2010 at 8:49 PM
Baron95 said...: Oh, if you want to see all the above findings you can go to the NTSB DL188 docs folder at http://www.ntsb.gov/Dockets/Aviation/DCA10IA001/default.htm; January 13, 2010 at 8:54 PM
Baron95 said...: By the way - this Delta flight was being flown by the "acquired" NWA crew, ops, plane.; January 13, 2010 at 8:55 PM
Phil Bell said...: No, I'm not dead (yet!)- just dead tired! :)

New headline post is up- sorry for the delay.

More of the same- investigation of "mass ratios" (empty vs mtow)- but for business jet class (sorta anyway) aircraft.

(And last of the same, for a while anyway- I hope the topic was not as exhausted as I am! :)

Some surprises- to me anyway.

Happy reading!

p.s.- For a future topic- I wish we had some good metrics on the costs of composite design and fabrication- feel free to speak up!

(Or email if you prefer: aviationcritic@gmail.com)
Thanks.; January 14, 2010 at 12:03 AM
Unknown said...: This was a useful post and I think it's fairly easy to see in the other reviews, so this post is well written and useful. Keep up the good work.
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Walkaway Tensile Structures Manufacturers in Jalandhar; February 15, 2021 at 10:37 PM

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Monday, January 4, 2010

Time to "Scale Back" our Expectations for Composites?

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