On 29th April 1975, America began Operation Frequent Wind – the evacuation of over 1,000 American civilians and a further 6,000 “at-risk” Vietnamese from Saigon. The largest ever helicopter evacuation lasted for 19 hours and involved 81 helicopters shuttling the evacuees to US Navy ships moored in the South China Sea.
With North Vietnamese troops closing in on the capital by March 1975, the US had already evacuated 45,000 people by April 29th. However, with fixed-wing evacuations impossible due to the approaching army, US Ambassador Graham Martin ordered the commencement of Operation Frequent Wind. American Forces Radio made their pre-arranged signal “The temperature in Saigon is 105 degrees and rising”, and followed it by playing Bing Crosby singing White Christmas. The evacuation began at around 2pm.
The main muster point was the Defense Attaché Office, from where thousands of people were successfully airlifted in a relatively orderly manner. However, at the US Embassy thousands more people had gathered – considerably more than it would be possible to evacuate even with helicopters landing every 10 minutes.
With hundreds of eligible Vietnamese civilians still at the Embassy, at 3.27pm President Ford ordered Ambassador Martin to stop evacuating anyone other than American personnel. The Marines guarding the compound were ordered to move further inside, and shortly afterwards the crowds broke through the gates. The last of the Marines were flown out at 7.53am, leaving approximately 400 evacuees still inside the Embassy when it fell to the Communists.