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 acronym 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 ( e . g . , USAF " Pedros " ) or may not provide en route care . The service exists to transport casualties that are in dire need for evacuation from the battlefield and do not have time to wait on a MEDEVAC , or where a MEDEVAC is unable to get to the casualty . 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 . So in a sense , MEDEVAC transports are dedicated aircraft to transport casualties , CASEVAC is any transport used to move battlefield casualties . " Dust Off " was the tactical call sign for medical evacuation missions first used in 1963 by Major Lloyd E . Spencer , Commander of the U . S . Army 57th Medical Detachment ( Helicopter Ambulance ) . The name lasted the rest of the war . Typically Air ambulances would lift wounded soldiers to a hospital setting in less than an hour after being wounded . Flying into an active landing zone to pick up wounded was a dangerous job . Peter Dorland and James Nanney wrote in " Dust Off : Army Aeromedical Evacuation in Vietnam " , " . . . slightly more a third of the aviators became casualties in their work , and the crew chiefs and medical corpsmen who accompanied them suffered similarly . The danger of their work was further borne out by the high rate of air ambulance loss to hostile fire : 3 . 3 times that of all other forms of helicopter missions in the Vietnam War . " All members of the US Armed Forces today are trained in some form of basic first aid . While lacking advanced life saving equipment and medical personnel in regular vehicles , all personnel today enter the combat zone with an Improved First Aid Kit ( IFAK ) on their equipment . The IFAK has basic medical supplies such as bandages , a tourniquet , and QuikClot gauze . Most units have stretchers and burn blankets in their vehicles . In the U . S . Military , the terms CASEVAC and MEDEVAC are used interchangeably by most soldiers . An aerial CASEVAC ( as defined by this article ) is uncommon . This is due to exhaustive efforts by the U . S . Military to ensure that dedicated MEDEVAC platforms with trained medical personnel are available in the event of a casualty . This has , in part , led to a 90 . 6 % casualty survival rate , compared to 80 . 9 % in World War II . In Australian military terminology , a CASEVAC refers to the evacuation of a small number of troops , usually just one .