It flew on a daring but unsuccessful raid to free American POWs in North Vietnam 38 years ago. Now, after subsequent tours in Bosnia and Iraq, helicopter No. 357 is being retired, and with honor. This particular MH-53 has made its final landing at the National Museum of the United States Air Force, where it went on permanent display on July 7.

The 88-foot-long special operations chopper, nicknamed “Magnum” after the gun, is the last to remain of the few helicopters used in the Son Tay raid in Vietnam in 1970. The Soy Tay raid used MH-53s in an attempt to rescue over 50 US POWs believed to be held at the camp in North Vietnam. No. 357’s final flight was a combat mission in Iraq on March 28.

The MH-53 was an upgraded version of the HH-53 “Jolly Green Giant”, with new engines, rotors and skins. Later the helicopters were equipped with infrared sensors, global positioning systems, and terrain-avoidance radar. There were originally about 70 MH-53s. There are still 12 in service, but those will be retired in September and replaced by the Osprey tilt-rotor aircraft.