Interesting Survey you came up with.

[5099]

I noticed under the “Suggestions for Tech Forum” there was a survey posted called:
“Is a generator an airframe part or a powerplant part”?

I found the answers interesting because the first 3 option answers were divided equally at 33%. Of course at the time I submitted my answer there were a total of 6 people answering, including myself.
If possible I’d like to see this survey listed under its own subject title. I’m wondering just how many people think that an engine driven generator is a powerplant item or an airframe item. Is a generator necessary to make an engine run?
JMHO, Steve.

[8170]

Its an accessory...

[2066]

Interesting, indeed! My own related survey locally has equally balanced answers (2 = airframe & 2 = engine). These "opinions" are from 1 "seasoned" FAA inspector and 3 "independent" IAs. Some very limited research seems to indicate that legal definitions may not jive with the opinions of technicians who may be turning wrenches & logging repairs, and the FAA seems to just "direct" that aircraft maintenance/accessory replacement must be properly recorded, 'though they apparently don't actually define the specific answer to John's question(?). (...see what you've started, John?! ). Mac

[5099]

Again, Interesting.
How about this? A Piper J3C Cub with a C-65, 75 or 85 engine (sound familiar)? Can not have an engine driven generator because there is not enough room between the engine and the firewall. So, an engine does not need an engine driven generator to run. Also, there is an STC to add an alternator to a C-120/140. The STC is an Airframe modification. If you remove the engine and sell it the alternator STC stays with the Airframe and not the Engine.
Got a headache yet?

[6643]

Just goes to show, how you word the question has a bearing on what answers you'll get. Maybe I should have asked "Which rating do you need to work on an engine driven generator, airframe or powerplant?

there is an STC to add an alternator to a C-120/140.

Carefull, you'll give away the right answer!

[1307]

The generator is listed in the Continental C85 engine parts manual, page 2-21, item 8. So it is an engine part.

http://veteranflyg.se/wordpress/wp-cont ... g-2011.pdf

[6643]

But, the generator is listed (separately) in the Cessna parts catalog, so, doesn't that make it an airframe part?

[6298]

The overhaul manual states "Service maintenance instructions relative to accessories installed on Teledyne Continental aircraft engines in our factory are reprinted herein by permission of the accessory manufacturers"
I agree with Johns'

[6863]

With all due respect, generators and alternators are not engine parts simply because in another era they were listed in the Continental C85 parts manual. In 2018 generators and alternators are airframe parts. They are not listed in the engine Type Certificate Data Sheet but are listed in the Airframe Type Certificate Data Sheet.

John Kliewer

[8240]

An alternator or generator is an engine accessory. Once the engine is installed into an airframe, any modification of it belongs to the airframe... this is evident in the light weight alternator conversions bearing STCs beginning with SA, the “A” designates an airframe modification. My supposition is its an airframe alteration because the alternator provides power to the aircrafts electrical system. Starters, also an engine accessory, when modified in the installed aircraft, are designated as an engine modification, and as such, the STC number begins with an SE, with the E meaning engine.
Any part, engine or accessory, has a manufacturers part number. You could technically buy a Continental C-85-12F thru your Cessna dealer using a Cessna part number. A propeller has a cessna part number in the cessna parts manual.
The line gets fuzzy under the cowling. Things like installing a brackett air filter conversions are an airframe modification, with an stc number beginning with SA... although you see the alteration (and element replacement)often entered into the engine logbools which is technically incorrect. Its also why you see the eligibility list according to aircraft types, not engine models. The induction system is part of the airframe.
When I took my IA exam 30+ years ago, this stuff was really hammered. Now, not so much.
Jim