A curiosity question re Type Certification

I’ve always wondered about this after attending a Cub seminar given by Clyde Smith years ago. He said the Type Certificate is the airplanes birth certificate. And it’s defined by all the drawings for the type. Ok, so that makes sense. You want different wingtips, you get an STC or a one time approval. You want to clip wings you have an STC for that.

A recent thread on flying with a gear leg uncovered piqued my interest. If the Piper drawings show the gear legs are covered, what’s the “official” position on this? Same thing about the interior of a J3 being uncovered. PLEASE DON’T GET ME WRONG.

I know there is no appreciable difference in leaving the gear uncovered and I wouldn’t have any problem doing that. I’m just curious under what authority things like this can be done? Or is it don’t ask don’t tell

Rich

No fabric on the gear legs and removing interior panels are changes not involving structural changes. I.e., the fabric on a wing, tail, fuselage, etc, is part of the actual structure of those components. If you leave it off, the aircraft won't fly or won't fly right. But if you leave the fabric off a gear leg, it will still support the aircraft as designed. Similarly, removing interiors has no effect on the structure of the airframe. No interior? Still flies as designed. Inter related to major vs minor modifications as listed in FAR 43.

Web

Perfectly clear. Thanks Web.

Rich,
As Web says, that's what they can get away with in Alaska. Around here years ago there was a J-3 on my field which had the fabric removed to be recovered. One day Mr. FAA came a visiting and placed a grounding tag on the plane. He never asked what the story was, just did it.

That happens here from time to time, also. Can't stop stupidity, not even with regulations. We can only fight back against it.

Web

Stc’d gear comes powder coated and uncovered


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Then you get out the definition of major alteration and have the fed demonstrate how an uncovered gear leg has a substantial effect.

It may slow you down a tad, but we do not have the equipment that could detect it.

bob turner said:

It may slow you down a tad, but we do not have the equipment that could detect it.

Click to expand...

I have seen reports that is good for 2-3 mph on an FX-3 Carbon Cub. They seem to cruise a bit faster than the PA-18. (About 100 mph TAS on 6.5 gph).

I was told not to get covered gear as it woud be quickly shredded. The best advice I ever had was - listen to all the advice then do what you want to do. My covered gear is still perfect but I can't say the same about the stab.

I covered the gear on my -12 with the hope for a speed increase. Near-zero effect.

RaisedByWolves said:

Stc’d gear comes powder coated and uncovered


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Click to expand...

So do tailfeathers, Tom LOL. Until someone dings me I have no issue with doing an annual on uncovered gear.