National Aeronca Association Bulletin Board

I was thinking about installing a Aeromatic prop on our DC Champ. Since our glorious FAA won't issue any field approvals in this state, my question is, is the Koppers (Aeromatic) prop on the Champ's Type Certificate? Would this hold true if the aircraft in question was converted to a DC, and has a C-85 engine?
Is there a web site where one can view the Champ TC?

Mike

http://www.aeronca.com/TCDS/

The Aeromatic is approved on the 7AC; and that's what your Champ started as..... I think. Even though it has been converted to a DC; the registration states 7AC. I would bolt it on a not ask questions.

nkh

Mike,
You and I have discussed this at a previous time. I was not able to get one approved on my Champ. But mine is a different issue. As Nate said, it is approved on the 7AC and it is approved on my engine (Lyc. O-235). But it is the engine airframe combination that was the "bump in the road". You may not have this issue with the 85hp though.
Give Aeromatic a call....he is a nice guy to talk to and may be able to give you the answer you want.
I still have access to the prop we discussed and I am STILL trying to find a way to install it. My AI has been around a long time and may be able to find the proverbial loophole.
Good luck and let me know how it works out.
WW

So go to another state, or get yourself a better mechanic. Nothing says you have to get stuff approved at the closest FAA office. Field approvals are still available.

I am STILL trying to find a way to install it

There are 6 bolts, way out on the pointy end.....

I'd be tempted to "test fly" that installation whilst pending approval....

If its on the type certificate data sheet, as I understand it there is nothing needed but a logbook entry to install it on the airplane. It is already approved, so no further approval from anyone needed.

If its on the TCDS then I would bolt it on and go flying. Keep a copy of the TCDS in the plane in case someone asks.

Joe A

When you start to modify the airplanes via the STC process you need to be careful using the TCDS information. It was approved for the model in an unmodified state. Part of the inspection criteria is to be sure that the modifications installed do not create an unsafe condition. If you have no information about a specific engine/prop installation, it might not pass the mustard on your next inspection.
Paul

Paul,
What you have said is the exact stumbling block I ran into. Due to the engine being changed to the O-235 via STC is the issue.
Keith

Do you have the Wagner STC? I'd have to look, but I believe there's an "or other approved propeller" clause, which should mean you only need a logbook entry.

Dusty,
Yes, it is the Wagner STC. I believe that is the wording also.....just got back to MN and need to dig the logs out of my safe to check. What you suggested in your previous post is exactly what I am doing....put it on and not worry about it. That is on the contingement that this prop is airworthy. My buddy gave it to me last year to put on but I didn't have the time to do it so I gave it back to him before I left for the winter. Only issue with these props is their cost for rebuild!!! I may not put my floats on this summer so I will be able to do this at my hangar.
Keith

"Don't ask don't tell"?

If it's on the TCDS, NP.

I'm still thinking about installing an Aeromatic prop. Is there a website where I can view the actual 7AC TDS?

Mike

Todd's site has it.

www.aeronca.com

From the Type Certificate:
Koppers Aeromatic F200/00-72D
Parts List Assembly No. 4324 revised February 21, 1949 (eligible on Models 7AC,
S7AC with A-65 engine only). Low pitch setting at 24 in. sta.: 13.5o
Static r.p.m. at maximum permissible throttle setting:
Not over 2300, not under 2200. No additional tolerance permitted.
Diameter: not over 72 in., not under 70.5 in.
When this propeller is installed, installation and operation must be accomplished in
accordance with Kopper's "Installation and Operating Limitations No. 22A."

It doesn't say anything about engines other than the A-65 so I don't think you could legally install it without a field approval. I'd talk to whoever owns the rights to it and see what they have to add. Perhaps there is an STC floating around out there.

Tim

Thanks Guys.
I'm going to call Tarver tomorrow and ask about installing a Aeromatic prop on a DC Champ. I had a IA tell me to, just go ahead and install it, and nobody would ever question its legality since it was on the TDS. I'd hate to spend the money and be required to take it back off, however.
I do know that an Aeromatic prop would really wake up a Champ, or any other light plane. I'll let you know what I find out.

Thanks,

Mike

I don't know anything about the Aeromatic Prop's but my only thought about "A-65 only " is the type of crankshaft allowed with this propeller. I think this prop will only install on a tapered style crankshaft and NOT a flange type crankshaft. That is the way the Beech 003 props are installed.

Legally if it only says A-65 engines only in the TCDS then that's it......unless someone has an STC for different application.

Just curious what is the overhaul/ IRAN inspection on these propellers???

DC Krog