Emergency flotation system

Emergency Flotation Systems (EFS) are emergency systems installed on larger commercial and military helicopters in order to prevent the airframe sinking in the event of a crash landing on water. The floats may be packed within spaces inside the airframe or as externally mounted packs on the helicopter skids. The floats are inflated using gas stored in pressurised cylinders carried on board the helicopter.

The most rapid inflation is provided by pressurised helium although some float systems use helium blended with other gases such as nitrogen to slow down the inflation rate.