Yes, we already found where the problem is, will be surely fixed before tomorrow (it's 1:49 AM now, and it's not a very good idea to work on a fix now).
If you want to fly with these airplanes without being bothered by the message, you can add an [Exits] section like this:
[exits]
number_of_exits=1
exit.0=0,0,0,0,0
OR, edit the exiting one, to have the format expressed as exit.N and then 5 parameters, what it's usually missing are the coordinates and the door's type, they might be all 0, it's not a problem, since that airplane wouldn't have worked anyway, but will at least prevent the error message.