Abstract
During the early days of helicopter operations, mainly in the Royal Navy, some aircrew lost their lives after a controlled ditching or a heavy landing onto the sea, when they became trapped in an aircraft which capsized and sank. The subsequent inquiries often proved that some of the victims were fit enough to have effected an escape and the cause of death was usually attributed to disorientation during the capsize and sinking. In some cases, the problems associated with disorientation were exacerbated by the accidental or positive operation of inflatable lifejackets, which made escape from the submerged helicopter virtually impossible.
Concern was such that helicopter underwater escape training facilities were built by the Royal Navy. The Royal Navy's commitment to helicopter underwater-escape training is shown by the fact that all helicopter aircrew and others whose duties cause them to fly regularly, must complete initial helicopter underwater escape training followed by refresher training every two years. (Reference No. 1)
Civil helicopters hopefully are not likely to be subjected to the possibility of being shot from the skies and descending in an uncontrolled manner. Should a civil helicopter have to ditch, due to some mechanical or electrical failure, it is reasonable to predict that it may do so in a controlled manner, with the pilot either taking the positive decision to ditch the helicopter, or being forced to do so.
