Casualty evacuation

Casualty evacuation, also known as CASEVAC or by the callsign Dustoff or colloquially Dust Off, is a military term for the emergency patient evacuation of casualties from a combat zone. Casevac can be done by both ground and air. "DUSTOFF" is the callsign specific to U.S. Army Air Ambulance units. DUSTOFF is an backronym meaning Dedicated Unhesitating Service To Our Fighting Forces. CASEVACs by air today are almost exclusively done by helicopter, a practice begun on a small scale toward the end of World War II; before that, STOL aircraft, such as the Fieseler Fi 156 or Piper J-3 were used. Casevac aircraft are a non standardized and non dedicated vehicle, that does not necessarily have en route care which is used to get a casualty back to another location where they can be treated by professional medical staff.

The primary difference between a CASEVAC and a medical evacuation (MEDEVAC) is that a MEDEVAC uses a standardized and dedicated vehicle providing en route care. On the other hand, CASEVAC uses non-standardized and non-dedicated vehicles that may or may not provide en route care. CASEVACs are commonly referred to as "a lift/flight of opportunity". If a Corpsman/Medic on the ground calls for a CASEVAC, the closest available unit with space could be called to assist; regardless of their medical capabilities. These could include U.S. Marine Corps aircraft such as the MV-22 Osprey or U.S. Navy SH-60 Seahawk helicopters. The guiding principles in a CASEVAC is to transport casualties that are in dire need for evacuation from the battlefield and do not have time to wait on a MEDEVAC. MEDEVAC aircraft and ground transport are mandated by the Geneva Convention to be unarmed and well marked. Firing on "clearly marked and identified" MEDEVAC vehicles would be considered a war crime under Article II of the Geneva Convention, in the same sense as firing on a Hospital Ship would be a war crime. CASEVAC transport are allowed to be armed since they are normally used for other purposes but carry no penalties for engagement by hostile forces.

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