Helicopters don’t come cheap, but then again neither does a war.

The Vietnam War is estimated to have cost the US $173 billion dollars, which adjusted for today’s inflation comes in at around the $900 billion mark. Of course the real cost of a war can’t be measured in dollars and cents, but numbers like those make you realise why pushing a few helicopters overboard is just a drop in the ocean.

One of the US Army’s largest mass evacuations took place in the final days of April 1975 as the North Vietnamese Viet Cong approached Saigon. Citizens and American troops were rushed to safety on American warships, although space on said warships was at a premium. Here’s Mashable describing what was code-named Operation Frequent Wind:

Such was the speed of the evacuation and the number of people involved that the ships became overwhelmed with people and the helicopters that had brought them. Orders were given to push surplus helicopters over the sides of the ships to make room for more. Some pilots were told to drop off their passengers, then ditch their machines in the sea, bailing out at the last moment to be picked up by waiting rescue boats.

Below are the iconic photos of the helicopters being plunged into the ocean.

[source:mashable]