Video: 'Iran Hostage Crisis' (Operation Eagle Claw at 2:49)

(Friday, April 25, 1980, 2:00 a.m. Iran Daylight Time) — Operation Eagle Claw, an attempt to rescue 52 embassy staff held captive at the U.S. Embassy in Tehran, Iran, was aborted early this morning after mechanical problems grounded rescue helicopters and eight U.S. servicemen were killed when a helicopter crashed into a transport aircraft.

Its failure, and the humiliating public debacle that ensued, damaged U.S. prestige worldwide.

President Jimmy Carter blamed his loss in the 1980 U.S. presidential election mainly on his failure to secure the release of the hostages (Carter spoke to the nation at 7:00 a.m. EST).

Video: 'President Jimmy Carter - Statement on Iran Rescue Mission'

The operation, one of Delta Force’s first, encountered many obstacles and was eventually aborted. Eight helicopters were sent to the first staging area, Desert One, but only five arrived in operational condition. One encountered hydraulic problems, another was caught in a sand storm, and another showed signs of a cracked rotor blade.

During the operation’s planning it was decided that the mission would be aborted if fewer than six helicopters remained operational, despite only four being absolutely necessary. In a move that is still discussed in military circles, the field commanders advised President Carter to abort the mission, which he did.

As the U.S. force prepared to withdraw, one of the helicopters crashed into a transport aircraft which contained both servicemen and jet fuel. The resulting fire destroyed both aircraft and killed eight servicemen.

In the context of the Iranian Revolution, Iran’s new leader, Ayatollah Ruhollah Khomeini, used the failed operation as a propaganda tool. He claimed that the mission had been stopped by an act of God (“angels of God”) who foiled the U.S. mission in order to protect Iran and his new conservative theocratic government.