Strange Mooney

[Jerry Pressley]

Just delivered a 64C with electric gear.  That's not the strange part.  The electric gear was out of a Comanche.  Seemed to work ok but must have been a nightmare to install. 

[steingar]

44 minutes ago, Jerry Pressley said:

Just delivered a 64C with electric gear.  That's not the strange part.  The electric gear was out of a Comanche.  Seemed to work ok but must have been a nightmare to install. 

And is completely unairworthy unless it's been moved into the Ex/Ab category.  Even then I don't think it's legal.

[Hank]

45 minutes ago, steingar said:

And is completely unairworthy unless it's been moved into the Ex/Ab category.  Even then I don't think it's legal.

Airworthiness all depends on the paperwork, which neither you nor I have seen. Field Approval? 337? I dunno, but apparently it can be done. But surely not easily (the actual job OR the paperwork for approval).

[Jerry Pressley]

i dunno.  been in there for lots of years and paperwork is there

[takair]

3 hours ago, Jerry Pressley said:

i dunno.  been in there for lots of years and paperwork is there

Did it still have the standard pucks?

[cctsurf]

22 hours ago, Jerry Pressley said:

Just delivered a 64C with electric gear.  That's not the strange part.  The electric gear was out of a Comanche.  Seemed to work ok but must have been a nightmare to install. 

If you've read about the development of the Commanche, I forget if it is in "The Al Mooney Story" or "Mr. Piper and His Cubs."  Al flew the the M20 into Lockhaven and Piper nicely kept it in the hangar there over night.  When Al returned the next morning, they were just screwing back on the last of the inspection panels...  The prototype commanche even had pucks like Mooney gear.  Those were later replaced by oleo struts.  Fitting Commanche gear to the Mooney may not be as difficult as one thinks.

I suspect that the Commanche gear would make greasing the landings in a Mooney easier...  But too much weight and too complex. 

[Guest]

Those who own them prefer to call them Comanches.  With them Piper fixed all of the Mooney shortcomings.

Clarence

[EricJ]

On 10/9/2020 at 11:39 AM, steingar said:

And is completely unairworthy unless it's been moved into the Ex/Ab category.  Even then I don't think it's legal.

A 337 makes it legal.

Many GA airplanes have electric gear with jack screws, and on the Mooney a pushrod connected to the jack screw replaces the johnson bar, so it's not a very complicated replacement process.

If there's a 337 it should be part of the particular airplane's FAA data package, and the data from it could be used to request a field-approval on a 337 to do the same on another airplane.

 

[jetdriven]

3 hours ago, M20Doc said:

Those who own them prefer to call them Comanches.  With them Piper fixed all of the Mooney shortcomings.

Clarence

except the efficiency. Ive flown plenty of Comanches and the 180s are underpowered and the 250's are not as good on gas.  But a fine airplane overall, just a different market segment.

[Jeph357]

Just to stir it up my plane has a 337 for  dual piston brakes that are from a.... you guessed it a Comanche. ( Or as I call my buddy's plane, the cosnatchy) I have more braking than I ever use.

[Raptor05121]

On 10/9/2020 at 1:53 PM, Jerry Pressley said:

Just delivered a 64C with electric gear.  That's not the strange part.  The electric gear was out of a Comanche.  Seemed to work ok but must have been a nightmare to install. 

like with oleo struts? Did you not take pictures?

[Guest]

10 hours ago, jetdriven said:

except the efficiency. Ive flown plenty of Comanches and the 180s are underpowered and the 250's are not as good on gas.  But a fine airplane overall, just a different market segment.

Both are fine airplanes and I’ve owned several of each.  Yes a Mooney wins in efficiency against a Comanche, but after that I think a Comanche wins in many other areas when comparing a Comanche to any Mooney up to an F model.

More room in the cabin, more useful load, no corrosion issues, fuel bladders from birth, lower landing gear maintenance cost.  These are some of the things I hear Mooney owners complaining about here. 

Clarence

 

[jetdriven]

Im taking care of a Twin Comanche, which is oddly efficient, for what you get for 17 GPH, but he said he has a gear AD where it all has to come out every 2000hr?

[Guest]

4 hours ago, jetdriven said:

Im taking care of a Twin Comanche, which is oddly efficient, for what you get for 17 GPH, but he said he has a gear AD where it all has to come out every 2000hr?

There is a 1000 hour gear inspection which calls for measuring bolts and bushings in the landing gear retraction system.  I have a set of go/no go gauges if you'd like to borrow them when the time comes.

Clarence

[steingar]

On 10/10/2020 at 7:06 PM, EricJ said:

A 337 makes it legal.

Many GA airplanes have electric gear with jack screws, and on the Mooney a pushrod connected to the jack screw replaces the johnson bar, so it's not a very complicated replacement process.

If there's a 337 it should be part of the particular airplane's FAA data package, and the data from it could be used to request a field-approval on a 337 to do the same on another airplane.

 

I suspect very strongly that a major alteration to a certificated airframe will not pass the smell test for most IAs.  Maybe the one guy pencil whipping the annuals.  You aren't allowed to do major alterations of certificated airframes except or experimental purposes, and there's a special classification for that.  And it can't remain experimental for long.  If you could there'd be no point to certification in the first place.

[Hank]

4 minutes ago, steingar said:

I suspect very strongly that a major alteration to a certificated airframe will not pass the smell test for most IAs.  Maybe the one guy pencil whipping the annuals.  You aren't allowed to do major alterations of certificated airframes except or experimental purposes, and there's a special classification for that.  And it can't remain experimental for long.  If you could there'd be no point to certification in the first place.

FAA Form 337 is for submitting planned Major Alterations to the FSDO for approval, before the work is completed. Once the 337 is approved, the alteration(s) documented on it are approved for that aircraft forever, no need for an IA to approve it.

https://www.faa.gov/forms/index.cfm/go/document.information/documentid/185675

 

Edited October 12, 2020 by Hank

[David Lloyd]

Maybe it was done 50 years ago when there were a lot of field approvals with little paperwork.  Once done, it was done.

[M20F]

On 10/11/2020 at 7:24 AM, M20Doc said:

Both are fine airplanes and I’ve owned several of each.  Yes a Mooney wins in efficiency against a Comanche, but after that I think a Comanche wins in many other areas when comparing a Comanche to any Mooney up to an F model.

More room in the cabin, more useful load, no corrosion issues, fuel bladders from birth, lower landing gear maintenance cost.  These are some of the things I hear Mooney owners complaining about here. 

Clarence

 

+2 

[RobertGary1]

2 hours ago, steingar said:

I suspect very strongly that a major alteration to a certificated airframe will not pass the smell test for most IAs.  Maybe the one guy pencil whipping the annuals.  You aren't allowed to do major alterations of certificated airframes except or experimental purposes, and there's a special classification for that.  And it can't remain experimental for long.  If you could there'd be no point to certification in the first place.

What right does an IA have to say he doesn't think some design is airworthy when the FAA has signed off on it? That would see to be at least a very immoral behavior on the part of the IA.

I had an engineer friend who thought his Aeronca could use another wing support strut. He put one on and the FSDO came out and looked at it shrugged and signed the 337. Crazy or not its 100% legal. If an IA later refused to sign an annual I'd hope that IA doesn't get much work in the future.

-Robert

[steingar]

20 hours ago, RobertGary1 said:

What right does an IA have to say he doesn't think some design is airworthy when the FAA has signed off on it? That would see to be at least a very immoral behavior on the part of the IA.

-Robert

Airworthiness has always been in the eyes of the mechanic, just how it is.

[JimB]

23 hours ago, steingar said:

I suspect very strongly that a major alteration to a certificated airframe will not pass the smell test for most IAs.  Maybe the one guy pencil whipping the annuals.  You aren't allowed to do major alterations of certificated airframes except or experimental purposes, and there's a special classification for that.  And it can't remain experimental for long.  If you could there'd be no point to certification in the first place.

Where in the world does this come from? Putting a different prop on, installing a JPI EDM 900 or a Garmin G5 via STC is a Major Alteration. That's how you "alter" a certificated aircraft using approved data and submitting the proper 337 paperwork. If it isn't via an STC, you can do it with an FAA field approval or other FAA Approved data. Experimental is different category of aircraft and has nothing to do with proper major alterations. 

Edited October 13, 2020 by JimB

[N201MKTurbo]

In IAs job is to insure the airplane conforms to the type certificate. The TC can be modified by STC which can be a one time STC (field approval) 

If the aircraft conforms to the TC (amended) and the IA won't sign it off, find another IA.

BTW, there is no requirement for an IA to return an aircraft to service, they only inspect it. If there are discrepancies, he just needs to list them and his responsibility is over. Any A&P can fix the discrepancies and return the aircraft to service.

I realize in most cases the inspector and mechanic are the same person and having another mechanic work on a plane that may not be easily movable is a problem.

Getting a ferry permit to fly a plane with discrepancies and/or out of annual to another maintenance facility is specifically allowed.

[Jerry Pressley]

On 10/11/2020 at 12:26 AM, Raptor05121 said:

like with oleo struts? Did you not take pictures?

the gear was normal  just the retract mechanism was comanche

 

[Raptor05121]

28 minutes ago, Jerry Pressley said:

the gear was normal  just the retract mechanism was comanche

 

I still don't quite understand.

[Yetti]

It sounds like they used a comacne gear activator rather than a Mooney actuator.   It's a motor and drive screw.    I believe the Older gear actuator was also used in a Cessna Flap assembly.