He shut off his engines, opened the cockpit, and in his haste to exit the aircraft to chew someone out about his having to wait, he hit the button that released his live bombs onto the deck of the Forrestal.
He took off running, as the bombs exploded, which set off a chain reaction of bombs from adjacent aircraft, and the ensuing explosions and fires killed 133 sailors aboard the Forrestal.
While his fellow sailors were fighting the fire, McCain went to the pilots lounge below decks and watched the men fight the fire on closed circuit TV.
Hours later, McCain took off with a New York Times reporter buddy of his, and went on to say that after seeing the effects of those bombs on the Forrestal, he was beginning to question the morality of dropping those bombs on the Viet Cong.
McCain was the direct cause of 133 deaths on his own ship, and was never reprimanded. He was nowhere to be found as the Forrestal had to limp to the Philippines for months of repair work.
This nonsense has been disproven time after time after time. Isn't there enough to criticize McCain for without resorting to lying about his military service?
I have seen about six versions of the story, all the way from McCain "hot dog" "wet start" causing the whole incident, to having him cause it some other way, to various "official" accounts. The account above seems to be from "JJ Paul McCartney" who doesn't actually exist.