Zuni Rocket Accident 1967
In July 1967, a fire broke out on board the aircraft carrier USS Forrestal. An electrical anomaly had caused the discharge of a Zuni rocket on the flight deck, triggering a chain-reaction of explosions that killed 134 sailors and injured 161. At the time, Forrestal was engaged in combat operations in the Gulf of Tonkin, during the Vietnam War. The ship survived, but with damage exceeding US$72 million (equivalent to $511 million today), not including the damage to aircraft.
I read a great book about this called "Sailors To The End"; another problem here was that many of the bombs were WWII era ordnance, the explosive in them unstable and more prone to heat and shock, considered much more sensitive than the modern '60s bombs. As for McCain, he did nothing to cause this -it was his plane that was HIT by the Zuni rocket, NOT the one that accidentally fired it.
After this incident, the Navy established a flag level committee to pursue improvements to the systems used to control flight deck fuel fires. An ordinance safety program was also initiated to characterize flight deck fuel fires and study ways to delay the "cook-off" times of munitions. As a result; insulation is now applied to some bomb casings, delaying "cook-off" times 5 to 10 minutes in a fuel fire, but does not diminish the violence of its explosive reaction.