Armed forces rely on Casualty Evacuation (CASEVAC) and Medical Evacuation (MEDEVAC) aircraft to transport:

• Wounded (combat) personnel;
• Injured (non-combat) personnel; and
• Ill personnel.

While borders between both types of mission can be fluid (and the terms sometimes used interchangeably, even by armed forces), there are some general factors defining each.

CASEVAC

CASEVAC is normally an emergency flight, transporting the patient directly from the field to the nearest medical/trauma facility, be it a field clinic or a regional hospital.

CASEVAC patients are transported after only basic battlefield care by fellow combat personnel or a combat medic, in the hopes of delivering the soldier to a medical facility within one hour of injury – known as the ‘golden hour’ during which wounded soldiers have the highest chance of survival.

While any qualifying aircraft can be used, dedicated CASEVAC aircraft are usually rotary aircraft capable of landing in unprepared terrain.

Some helicopters are specifically equipped for the CASEVAC mission. However, since evacuation is time critical, CASEVAC missions are frequently performed by the nearest general-mission aircraft, with only ad-hoc configuration to accommodate litter patients and (perhaps) a medical attendant.

Many armed forces do not maintain specialised CASEVAC aircraft.

MEDEVAC

In contrast, MEDEVAC flights normally transport patients in a stable condition after they have received care in a medical facility.

While CASEVAC flights tend to cover comparatively short distances, MEDEVAC flights tends to cover medium- to long-distance flights.

They can transport patients from field hospitals to regional medical centres, or repatriate them from overseas to major hospitals in their country of origin.

While rotary aircraft can perform shorter range missions within a theatre of operation, longer range MEDEVAC flights must be performed by fixed wing aircraft.

Since MEDEVAC flights are normally pre-planned, there is time to await the availability of aircraft specifically configured for such missions. This includes dedicated MEDEVAC aircraft as well as general purpose transports which can be configured with a MEDEVAC module.

Aircraft dedicated to the MEDEVAC mission are marked with the Red Cross symbol as international law prohibits firing at these aircraft. These aircraft are generally designated as MEDEVAC even when employed in the CASEVAC role.

Unmanned CASEVAC

Over the past decade, there has been increasing interest in the potential of unmanned aerial systems (UAS) for the CASEVAC role.

Benefits would include:

• No risk for human flight crews;
• Some (but not all) UAS would be smaller than manned aircraft, making them less detectable and permitting landing in a smaller space; and
• Potentially faster response times as dispersed field units could keep their own smaller CASEVAC USA on call.