I did test hundreds of times with different planes. I got the same result. Bigger the wing the more likely you will die. I would get past this by making the wing be hundreds of diffrent parts but eventually the game dies. I would ask that you make it so the wing doesn't brake in a few shots... that also gives me a idea of armor. It would be a slider in the setting for fuseladge blocks that increase the durability of it. (If you wan't to know what got furthest it was a personal Fokker triplane i made so long ago. Its small stubby wings didn't get hit once.)
@PilotOfFuture most of my craft don't have fuselages over the wings. I tried to put some over them recently but the wing bent down when I put up the gear. The plane also seems to have problems maneuvering if I do. I set the fuselage to zero mass.
You can just add layers of fuselages over wings and fuselages. Good point tho