Single Piece Avionics Access Panel STC? (Pre-J)

[Trenta]

Hello MS!

Does anyone know of an STC for the leaky three piece avionics panel that allows for a single piece? On the older B,C,E models. I am wanting to close that area up better as I look to start IFR training. There was a headache of a few hours in a bad rainstorm (hurricane) with wet radios shorting out and a couple gauges that went inop (I posted about that one a few months ago). 

or is there another route to work with an AP/IA and a FSDO to get a field approval for a modification? Or a 337?

I'm sure folks have done it. I would love to hear how they did it *In accordance with regs*. I looked for another thread on this but yielded no results. 
 

-Trent

[Andy95W]

Making a one-piece avionics cover fits the definition of a minor modification to a ‘t’.  Nothing about it would require an STC or field approval.  All it requires is an A&P who is willing to do the work to make a cover that fits and seals out of a single piece of aluminum that is comparable to the original and do a simple logbook entry.

If I didn’t have a 201 windshield, I would make one for my M20C because it’s a great idea.  (I’d make it out of .032 2024T3 aluminum.)

Andy

A&P/IA

[Trenta]

21 minutes ago, Andy95W said:

Making a one-piece avionics cover fits the definition of a minor modification to a ‘t’.  Nothing about it would require an STC or field approval.  All it requires is an A&P who is willing to do the work to make a cover that fits and seals out of a single piece of aluminum that is comparable to the original and do a simple logbook entry.

If I didn’t have a 201 windshield, I would make one for my M20C because it’s a great idea.  (I’d make it out of .032 2024T3 aluminum.)

Andy

A&P/IA

This was precisely the conclusion that I had come to as well via some light reading and this article. The recruitment for a willing A&P starts at dawn! Haha 

[carusoam]

That’s interesting...

Why is it three pieces to begin with?

Accessing one side at a time?

Some Mooneys had a transponder or other antenna in the middle, adding another hole to leak...

Making it one piece would cure the most leak prone part, that is over the most water sensitive items...

+1 for having a mechanic with good sheet metal skills... 

Go MS! 

PP thoughts only, not a mechanic...

Best regards,

-a-

[M20F-1968]

I know the general wisdom is that forward of the aft end of the steel cage, the steel cage and wing are structural, and everything else is there to keep the wind out.  However, the windshield is exposed to significant pressure and is supported by the cowl deck.  I am not saying it can not be done, but I am saying that someone may look at it a more than a minor alteration and ask that a DER be involved working through the numbers.  

I do not see where opening it up further would make it seal better.  Placing a better flange and better seal is a different story.

John Breda

[takair]

The problem I see is that there would be a double compound curve in a single piece....at least for my vintage. It would be very difficult for one person to install where it needs to slide under the cowl. I replaced the center piece that. Anthony mentioned with heavier gauge and no center hole. Added seals on the center piece itself. Also, cleaned the rain channel and new seals. An extended cabin cover also helps a lot. 

[chriscalandro]

You need to take the cowling off to remove those parts anyway. 
 

I believe the answer from before was to use silicone to seal it better, but I’m on board with a single piece retrofit. 
 

shouldn’t be terribly difficult or expensive to do. 

[Immelman]

3m strip caulk... dirty hands... no leaks.

[N201MKTurbo]

15 minutes ago, bluehighwayflyer said:

Something like this, you mean?   Looks nice.  Seals better.  Has been in service for over 35 years with no issues.  

Oh, man I'm going to call the feds! that looks like an illegal cover! Where is the STC?

 Looks great, nice jab!

[Brian E.]

1 hour ago, bluehighwayflyer said:

Something like this, you mean?   Looks nice.  Seals better.  Has been in service for over 35 years with no issues.  

You have "wings" on your oil access screws!  I need a flathead screwdriver to open mine.  I'm jealous and calling the Feds as well

[Hank]

2 hours ago, bluehighwayflyer said:

Ha!   You are right.  That must have been a mod by the original owner.  I had always thought the winged Dzus fasteners were stock, but I just looked it up and the IPC does indeed call for FJ4-35 flush studs.  I am all for drag reduction but I must admit that it is nice being able to check the oil without a screwdriver.  
 

 

My C has recessed pop-up levers, from the factory. No photo yet . . .