[geocrasher]

Yes but are they printed with PLA or PETG, or even ABS? Or are they using material designed exactly for their use case, and tested thoroughly before being certified for flight?

Or do they get their parts from some vendor at a swap meet who spends most of his time fiddling with his Ender 3?

[jacquesm]

Neither of those is suitable for this application. Ultem or PEEK. Anything else would be a very bad idea, and even for those two you would want to do a lot of testing.

[geocrasher]

That was my point. They used the wrong filament. And there isn't really a right one for the cowl of a single engine aircraft