Right on. Clearly if there is any question about the structural integrity the plane shouldn't be flown regardless of whether the FAA knows about it. Of course the question is, how do we know if there's a structural problem? The official answer would be that an IA has inspected the repair, and filled out the correct paperwork to indicate that it was done to FAR standards.
The missing piece of the puzzle is: If the paperwork was never filed, what can be done after the fact? (Especially years later). Could it be resolved by an IA filling out new paperwork? My understanding is that the 337 must be filed within a limited time after the repair is accomplished (I don't recall the exact period, 30,60, 90 days?)
So in a case like this, is the airplane legally unairworthy? If so, it's easy to understand why the owners since the repair have adopted "don't ask, don't tell"
Is there any solution to this, other than a current IA signing off the repairs (both unlikely, and perhaps unethical, since he/she would have to pretend the repairs were recently accomplished.) Or is the only redress having the repairs done over, and new paperwork filed?
One reason that I'm taking a special interest in this is that we commonly hear from owners who discover STC or 337 paperwork that is in their logbooks was never filed with the FAA. It takes a degree of diligence to discover this in the first place. These are rarely major items like wing repairs. For example, a recent issue was a digital OAT gauge, properly installed, but the paperwork was never filed with the FSDO. If the owner followed the letter of the law, her airplane would be grounded pending approval, which might take months, or never come. She could either remove the OAT gauge to return the airplane to airworthy status, or do nothing, and continue to fly, the obvious path of least resistance.
It's an interesting dilemma.
