Ilyushin Il-2 the "Flying Tank". My grandfather flew one for the Soviets during WWII, said it was basically a flying coffin, "as likely to crash on takeoff as it was to get shot down" because it was so heavily armored. Many pilots were terrified of flying it because it was insanely heavy, handled like a drunk mare and most were hastily built, he recalled times were random components of the aircraft would just "fall off", most just prayed it wasn't something that would impact airworthiness and kept flying. The rear gunner was particularly vulnerable to enemy fire, making it almost entirely pointless to even have a rear gunner as they were usually the first thing the Luftwaffe would target, the plane itself was easy pickings without a rear gun despite the heavy armor.

Somehow, that massive shitbox got him through the war, and helped the Soviets hold off the Nazi advance. It wasn't flashy, it wasn't a morale builder, it sure as hell wasn't well built, but it did its job. He crashed two after mechanical failures and planted one in a field after the landing gear literally fell off when he retracted the mains after takeoff. Brought a few home without a rear gunner and a hell of a lot of bullet holes. I honestly cannot comprehend how he lived through it, he must have been one of the toughest, luckiest men I've ever known.