Sunday, January 24, 2010

Reading and Writing...Volts and Bits

I was impressed with the mechanically-oriented Airframe and Powerplant classes, as discussed last week. While browsing the school's bookstore, I was also impressed with the texts for the avionics program. (I had originally thought they were included in the A&P program, but it is a separate track. (Many student's continue with it after the A&P I'm told).

I hadn't encountered anyone with the certification, but the The National Center for Aerospace & Transportation Technologies, NCATT ( (formerly called the National Center for Aircraft Technician Training), offers professional accreditation. (I don't think it's part of the FAA processes, yet anyway). The local school issues a graduation certificate, and then one can continue with the optional NCATT certificate.

Interestingly, it would seem both the A&P and avionics certification are increasingly helpful in a number of industries, as employers seek qualified candidates. The wind energy business was in particular pointed out, both for the A&P mechanical applications, and the electronic control and power distribution aspects.

The following syllabus is the one followed by my local institution, in the past it has been a four-term program, and the fifth term is an option for those pursuing the national certification.

Session 1 (15 weeks)13 credit hrs
Technical Mathematics3
Basic Electricity and Electronics3
Basic Electricity and Electronics Lab4
Introduction to Avionics3

Session 2 (15 weeks)7 credit hrs
Avionics Systems & Troubleshooting2
Avionics Systems & Troubleshooting Lab2
Basic Communication Electronics3

Session 3 (15 weeks)8 credit hrs
Wiring and Cannon Plug Lab2
Aircraft Electrical, Comm & Nav 13
Aircraft Electrical, Comm & Nav 1 Lab3

Session 4 (15 weeks)10 credit hrs
Aircraft Electrical, Comm & Nav 23
Aircraft Electrical, Comm & Nav 2 Lab3
Basic Communications Electronics Lab4

Session 5 (15 weeks)11 credit hrs
Principles of Avionics3
Certification Preparation for NCATT 13
Certification Preparation for NCATT 23
Global Professional Standards2

The reading list for do-it-yourselfers (and study-it-yourselfers):

Basic Mathematics for Electricity and Electronics ($219)

Grob's Basic Electronics: Fundamentals of DC and AC Circuits ($151)

Grob's Basic Electronics: Experiments Manual ($80)

Grob's Basic Electronics: Problems Manual ($77)

Avionics Training- Systems, Installation and Troubleshooting ($69)

Avionics Databuses ($127)

Introduction to Airborne Radar ($159)

Basic Communication Electronics ($69)

Aircraft Wiring and Electrical Installations ($27)

Automatic Flight Control ($117)

Avionics Troubleshooting and Repair ($46.50)

Avionics Systems: Operation and Maintenance ($25.50)

Aircraft Instruments and Integrated Systems ($120)

Avionics Test Equipment Handbook ($86.50)

Aircraft Electricity and Electronics ($106)

Some of these are a bit dated- going back to the mid 1990's (ahem). I suppose a large percentage of general aviation aircraft are even older, so maybe not such a big deal. Good reference material anyway. (The "Grob's Basic Electronics: Fundamentals of DC and AC Circuits" in particular looked like a handy starting point aspiring students and DIY-ers to become familiar with).

Things change- the textbooks, as well as the test equipment. Seems like all the Oscopes I see anymore are the digital LCD ones. (And just after I figured out how to set the clock on my VCR, along comes DVDs... "Just when you figure out the answers, they change the questions".

I've *almost* overcome that digital trepidation because of the multi-color traces available with Tektronix "Digital Phosphor Oscilloscope" (DPO) - and probably a lot of other manufacturers. Interestingly, Hewlett Packard is no longer among those competitors, having ditched the test measurment business with a controversial spin off (Agilent). No shortage of controversy at HP, for sure. Here's a link to some of the "real" stuff though.

As typical, Wikipedia has a nice article on Oscilloscopes. Scroll down a bit, and you'll come across the "Digital Storage" section, and note:
"The first Digital Storage Oscilloscope (DSO) was invented by Walter LeCroy (who founded the LeCroy Corporation, based in New York, USA) after producing high-speed digitizers for the research center CERN in Switzerland. LeCroy remains one of the three largest manufacturers of oscilloscopes in the world."
Intereseting- I though of CERN (allowing my crude translation of things backwards- Center of European Research into Nuclear Stuff- I guess they left the "S" off) as a recently developed organization, but it dates back to 1954. Lot's of publicity about the Large Hadron Collider.

I would suspect a certificate in Avionics might be a good resume item for these other high tech industries- wind farms today, fusion reactors tomorrow! (Unfortunately, fusion energy seems about as far off as the flying car...).

Of course, there have been a variety of approaches to the flying car thing. But let's hope that regardless of the industry they enter, our friends with avionics certificates can get their career's off the ground!

(Or at least into high gear- not reverse! :)

Monday, January 18, 2010

Read'n, Writin', and... Riveting ??

A funny thing happened on the way to the airport near where I lived, about, oh, 20 years ago or so. I stopped by a hangar the local junior college had, which was offering Airframe and Powerplant classes. The time requirement was substantial- can't remember the specifics, but it was 18 months, something like 4 hours per night, 5 nights per week, AND all day Saturday. Yikes! Sounded like great fun, but too much time.

Fast forward 20 years or so. And over the holidays, a funny thing happened on the way to a different airport...

This time, I looked a bit deeper into the programs. I'm sure there are a lot of great programs around the country (and world- although I confess to being ill informed about programs in other countries (and am just becoming somewhat literate about those in the USA).

I thought other folks might enjoy what I've discerned as the requirements- or at least what seems to be the typical requirements at a community-college level program. (There are "professional" programs at for-profit schools, Spartan being one of the leaders, I believe. And a number of 4-year programs, Parks College being the one I am most familiar with. But there seems to be more 2-year programs, some offering the training/certificate for only the A&P license, although most offer an associates degree with only a few more classes required).

As I understand it, there are three parts of an "Airframe and Powerplant" license (certificate, actually, although all the other unknowing non-A&Ps like me seem to universally refer to it as a license); the "General" (math, physics, blueprints, FAA regs, etc), the "Airframe", and the "Powerplant". One can obtain and Airframe, or a Powerplant, or an Airframe and Powerplant certificate.

The requirements for the certificate can be met with either work experience or academic training. The work experience is 18 months for either the Airframe or Powerplant, or 30 months for both. The academic training option is the General plus Airframe, or General plus Powerplant, or all three for the full "A&P". These are the requirements to be eligible to take the FAA written tests, after which one takes an oral exam, and a "practical" (hands-on) exam which is administered by a DME (Designated Mechanic Examiner).

I would think military experience would be one way to meet the experience requirements, and probably a number of jobs at an airframe manufacturer or "mod shop". (One challenge might be over-specialization though- perhaps some readers can shed light on this avenue).

The academic route consists of 1900 hours of supervision and instruction. Not including breaks. That's a pretty fair amount of time. (The "General" portion is 400 hours, "Airframe" is 750 hours, and "Powerplant' is 750 hours). For a four-year program, with two 16-week semesters, that's 3 hours per day x 5 days per week x 16 weeks x 2 semesters per year x 4 years. Make that 3.5 hours per day or so, to include breaks. Or, for a two-year community college, that's 7 hours per day or so, including breaks. Or shorter days, but more of them, if one includes Saturdays and the summer terms.

Where I live, the program is offered during the day, and during the night, as a five term program, with three 15-week terms per year- one "General", two "Airframe", and two "Powerplant" terms. The day class meets 7AM - 3 PM, Monday through Thursday; the night class meets 4 PM - 10 PM, Monday through Friday, with appropriate breaks to make it 25 hours of classroom and "lab" time per week. Any absences must be made up, down to the minute, so it's a pretty demanding schedule.

Here's the list of classes, in the normal order they are taken, at the community college (A&P(with associates degree)/vo-tech (old terminology, I suppose; the A&P certificate only).

Session 1 (15 weeks)23 credit hrs
Technical Mathematics2
Physics & Aerodynamics2
Basic Electricity4
Aircraft Drawings1
Maintenance Publications, Forms & Records2
Mechanic Privledges & Limitations1
Ground Operation & Service2
Weight & Balance2
Materials & Processes4
Fluid Lines & Fittings1
Cleaning & Corrosion1
General Review & Test1

Session 2 (15 weeks)23 credit hrs
Wood Structures1
Aircraft Coverings (Fabrics)2
Aircraft Finishes2
Sheet Metal & Non-metallic Structures8
Aircraft Welding2
Assembly & Rigging4
Aircraft Fuel Systems2
Hydraulic & Pneumatic Systems2

Session 3 (15 weeks)25 credit hrs
Aircraft Landing Gear Systems4
Position & Warning Systems1
Aircraft Electrical Systems6
Fire Protection Systems1
Aircraft Instrument Systems1
Ice & Rain Control Systems1
Cabin Atmosphere & Control2
Communication & Navigation2
Airframe Inspection3
Airframe Review & Test4

Session 4 (15 weeks)26 credit hrs
Reciprocating Engines11
Turbine Engines9
Engine Fuel Systems1
Auxillary Power Units1

Session 5 (15 weeks)24 credit hrs
Engine Instrument Systems1
Engine Fire Protection Systems1
Engine Electrical Systems2
Ignition & Starting Systems3
Engine Lubrication Systems3
Engine Cooling Systems 1
Fuel Metering Systems4
Induction & Airflow Systems1
Engine Exhaust & Reversers2
Engine Inspection2
Powerplant Review & Test4

Optional Courses to complete A.S. Degree18 credit hrs
English (Communications)3
Humanitities Elective3
Social Science Elective3
General Elective 13
General Elective 23
Computer Science3

So what if you don't have time for the classes- but If you're like me, the topics sound really interesting? Home study won't do much to geting a A&P certificate, but flipping pages at the community college bookstore was interesting. Here's a reading list, which seems to compose (I think:) the entire booklist of one typical A&P curriculum. I've listed the prices at the JuCo (yeah, that's another oldie term) bookstore. Sometimes on-line is cheaper, sometimes, a little higher. In general, I like to support the brick and mortar stores.

FAR/AMT 2010: Federal Aviation Regulations for Aviation Maintenance Technicians ($25)

Ac 43.13 - 1b/2b Acceptable Methods, Techniques, and Practices of Aircraft Inspection and Repair ($25)

The Aviation Dictionary for Pilots and Aviation Maintenance Technicians ($21)

Aviation Mechanic Handbook ($15)

Aircraft Electricity and Electronics

Aircraft: Basic Science with Student Study Guide ($62)

Aircraft: Powerplants with Student Study Guide ($110)

ASA General Test Guide 2010 ($14)

ASA Powerplant Test Guide 2010 ($14)

ASA Airframe Test Guide 2010 ($14)

Aircraft Gas Turbine Engine Technology ($107)

Airframe & Powerplant Mechanics Powerplant Handbook ($20)

Airframe & Powerplant Mechanics Airframe Handbook ($20)

Aviation Maintenance Handbook - General ($40)

Aircraft Maintenance and Repair with Study Guide ($110)

The whole books tab comes up to about $700 or so. Tuition at most CC's is around $100 per credit hour, which comes out to about $3000 per "term" for my local A&P school. Multiply by five terms, throw in tools for $2K and FAA exams, the total for an A&P license is probably $18K or so. I'd guess it's around double that for a private for-profit school.

The investment in time is equally expensive, especially if one is working full time: figure 70-80 hour weeks between work and school- sometimes in five days. Lot's of folks have two full time jobs (boy, do I have a lot of respect anyone doing that, or this!). Generally, loans are available to help with the financial burden. The time constraints are less easily ameliorated. Does the A&P certificate "pay off"? I would think so, over time. And it opens doors to opportunites that might otherwise be unavailable. Even at one's present job, it might be the differentiator when layoffs come, or a promotion comes along.

Plus, it looks like a heck of a lot of fun!

Best wishes to all who might be interested in an A&P program- perhaps some are currently enrolled in one. (I know several of our fellow bloggers are already A7P certificate holders).

Wikipedia article on Aircraft Maintenance Technician (AMT) Certification.

Find an A&P school near you. (Something like 170 or so to chose from in the USA).

Tuesday, January 12, 2010

Composite Aircraft Part 2 (Biz Jets and such)

Well, after our expose' last week on the ratio of empty weight to maximum takeoff weight, I am sure to have established my credentials as a half-wit amongst our learned stress engineer friends.

But why leave things only half done? Ignoring the advice of one of my favorite Presidents ("Don't get caught"... -oops, that was Tricky Dicky...but I imagine that's pretty much what they all say),

"Better to remain silent and be thought a fool than to speak out and remove all doubt. "

(Well, I think Abe Lincoln would not be accused of trying to not-get-caught. Although he was accused of just about everything else- politics was probably even uglier then than now, although it seemed some common sense and civility was briefly evident during the 1950's through 1980. Oh well, accidents happen).

Anyway, here we go with a review of business jets (or let's say, business aircraft- as I've included a few turboprops. All twins though, (well, or triples, or quadruples, in a few cases. And, a few Single Engine Jet's...Make that ALL the SEJs :). I deliberately did not include pistons, just to try to try to keep the scope narrowed. I'm sure I also missed a number of great foreign (and probably domestic) aircraft which would well qualify for inclusion- go ahead and mention your favorites, and I'll put them in the tables.

I believe it was Julius who mentioned the Beech Premier as being a notable exception to the laundry list of "failed" composite programs. And inconvenient truth, as it were, to my thesis that composite aircraft (commercial anyway) are:

1) Heavier than their aluminum counterparts
2) Cause cancer and baldness and explode all the time

(Okay, just kidding about that last one:)

My discomfort with a "disruptive" outliar- oops, not talking about former Eclipse stuff- some would insist that the correct terminology in that case would be out-right liar; however in this case: Outlier (interesting read, btw) variance of the Premier program, into the realm of commercially successful composite airplanes, did prompt me to compile a short list of what I had considered "failed" composite airframe programs, versus their nearest successful aluminum competitors. The results were modestly surprising, and challenged a few perceptions I have held about some of these programs. (These are the numbers I found on the web, ymmv, etc.; please post a correction if you see anything too far off, but I believe these numbers use the same methodology, allowing reasonably accurate comparisons).

ManufacturerModelEmpty WtMTOWRatio
BeechPremier I8430125000.674

Adam A-700 versus the Cessna Mustang. I had always thought the Adam looked like a porky little critter, and would surely be a heavy pig compared to the Mustang. But weight ratio wise, no- the Adam was quite respectable (the Mustang isn't too bad either). I suspect the aerodynamics of the A-700 weren't quite as good though. But, the composite Adam failed, the aluminum Mustang succeeded. Not saying it was the airplane's fault- just a data point. This round- Commercial success: Composites 0, Aluminum 1; Technical success: Composites 1, Aluminum 0.

The ,Beech Premier I (a Premier II is in development) versus the CJ2+ was also a bit of a surprise- I figured that since the Premier was successful, it would have a great advantage over the Cessna- but no, the Premier has a "heavier" ratio than the Cessna (which was also a commercial success). This round- Commercial success: Composites 0.5, Aluminum 0.5 (tie); Technical success: Composites 1, Aluminum 0.

The Grob SPn was one of my favorite development programs. Although it was still early in it's development program, with the likelihood of weight gain as certification changes dictated. But it failed commercially. Or rather, the company did. But again, it's a data point. This round- Commercial success: Composites 0, Aluminum 1; Technical success: Composites 1, Aluminum 0.

I think everyone (including me!) wants to root for the Beech Starship. But it was a financial disaster- only 50-ish were built, and all were bought back to be destroyed. (Well, most of them brought back anyway- a few still in circulation: I saw one fly by a few months ago). And it was heavy. This round- Commercial success: Composites 0, Aluminum 1; Technical success: Composites 0, Aluminum 1.

The last comparison is the Hawker Horizon/4000 versus the Bombardier Bd-100/Challenger 300. (The names of both airplanes changed over the past few years, as indicated). These two airplanes are about as close as it gets to direct competitors- they even had their first flights just 3 days apart. The Horizon is another airplane that has been a financial disaster, with a long development program, and low deliveries to date; the aluminum CL-300 has been a great commercial success. But, the Horizon is slightly better weight ratio than the CL-300, so I'll give it the technical nod. This round- Commercial success: Composites 0, Aluminum 1; Technical success: Composites 1, Aluminum 0.

So, "what's the score" for this five-pair comparison?
Commercial success: Composites 0.5, Aluminum 4.5
Technical success: Composites 4, Aluminum 1.

(I biased the technical success in favor of composites- as long as it was not deficient compared to the aluminum competitor).

To me, the surprise was not that the composite airplanes are so well represented in the financial failure category- which is mostly what I have observed. Rather, the surprise was that they indeed really ARE a bit lighter than their aluminum competitors. I guess I had attributed their financial failure to having a poor weight ratio, but it seems that is not the case.

So if the weight ratios are superior, why the financial failures? I would say, one big contributor, is the cost associated with development of a composite airframe. (Of course, it has been a difficult time economically, for all manufacturers, aluminum OR composite- but still, there seems to be some correlation apparent).

Further observations of the commercial ramifications of composite airframe development:
The A380 was 2 years late...
The 787 is over 2 years late...
Grob who was designing the composites for the Lear 85 (as well as their own SPn) went bankrupt.

I'm not saying there is a direct link between commercial fiasco and composites, but it seems the Premier is the only exception to that hypothesis so far. (Yes, there are lots of orders for the 787, so it may eventually break even. And over the course of years, be profitable. But I think it would have been more profitable, more sooner (er, something like that), if it would have been built of aluminum. (And yes, most of these airplanes are largely aluminum. But I still say there is a correlation between using composites and financial success- or lack thereof).

SO- if that was fun, how about comparing ALL the biz jets (and some select turbo props) ??

I strove to use comparable weights (empty without crew). In general, it seems differences in the empty weight:MTOW of 0.02 are where it gets "out of the noise", and 0.05 seemed to be especially relevant.

Another surprise- while the "sturdy" Kingair line dominates the bottom of the empty:mtow ratio table- but it's interesting to note what's at the second-to-last position. (Hint: Hondajet. And rather dramatically so. (We'll be discussing the Hondajet in a future "headline" thread). Almost as surprising, the Bombardier/Canadair Challenger-series came in at the top- in spite of having the appearance of being rather short and, well, dumpy. (Beauty is in the eye of the beholder though- no offense intended. And it has a great weight ratio!)

So, how did "our favorite VLJ" do? The Eclipse EA-500 scored a very respectable 0.597. Given the rumored weight gain, and deviation from the optimal configuration (rumored to be 40% or so)- that competitive number is all the more impressive. (Congratulations to the structural design team!)

ManufacturerModelEmpty WtMTOWRatio
LockheedJetStar I18450389400.474
DassaultFalcon 7X34072700000.487
DassaultFalcon 900EX23875483000.494
DassaultFalcon 900B22611455000.497
BombardierGlobal Express48800960000.508
DassaultFalcon 5020170388000.520
CessnaCitation III11670220000.530
DassaultFalcon 50EX21700407800.532
CessnaCitation SII8060151000.534
GulfstreamG-200 (Galaxy)19200354500.542
LockheedJetStar II24178445000.543
CessnaCitation I6631118500.560
IAIWestwind II13250235000.564
IAIWestwind II11750207000.568
DassaultFalcon 20018290320000.572
DassaultFalcon 1010760187400.574
CessnaCitation Ultra9395163000.576
DassaultFalcon 10011145193000.577
DassaultFalcon 200020735358000.579
DassaultFalcon 2016600286600.579
GulfstreamG-100 (Astra)14400246500.584
CessnaCitation X21700364000.596
Aero Commander690A6126102500.598
EmbraerLegacy 60030000496040.605
CessnaCitation X22100361000.612
BeechKingAir 3509326150000.622
CessnaCJ1+ (source1)6765107000.632
CessnaCitation XLS+12800202000.634
EmbraerPhenom 30011450180200.635
SwearingenMerlin IIB6452100000.645
PiaggioAvanti II7500115500.649
Aero Commander10007289112000.651
SwearingenMerlin IIC8150125000.652
EmbraerPhenom 1006932104720.662
BeechPremier II9120137000.666
BeechPremier I8430125000.674