The B-17 Flying Fortress could take incredible damage and still fly.
Here is some amazing proof.
This B-17 flown by pilot Glenn Rojohn of the 100th Bomb Group collided with another on a mission. Rojohn piloted the craft, which were stuck together, until both crews could bail out. Most survived.
Read the entire incredible story here on the 100th BG website: www.100thbg.com/mainpages/crews/crews5/rojohn.htm
Here are some other amazing stories of an incredible machine and crews who refused to die. The plane directly below was hit in the tail, blowing the tailgunner out. He parachuted out and became a POW. The plane returned to base safely.
The B-17 below, from the 398th Bomb Group, managed to return to base despite losing its nose to flak. The bombardier was killed instantly in this hit.
Despite being practically severed in half in a collision with a German fighter, this B-17 , named "All American" of the 97th Bomb Group, flown by Pilot Kenneth Bragg, limped back to its base in England, then broke apart on landing. SOURCE: Flying Forts by Martin Caiden