An Interim Report on the Developments of Safe Underwater Escape from Helicopters

Abstract

Executive Summary

This working paper is the advisory report for Package 26f, RO4, assignment 4XX, the customer for which is DDORS (Air). Its purpose is to review the global developments that have taken place which contribute to safe underwater escape from helicopters. These include improving crashworthiness; keeping the aircraft afloat; providing training and escape aids for aircrew and passengers; improving the location, release and exit through emergency hatches; and awaiting subsequent rescue. Information has been obtained from accident data, experimental research and training experiences.

Safe underwater escape begins on the ground by ensuring that helicopter aircrew regularly obtain the appropriate survival training. Additionally all passengers should be given comprehensive pre-flight briefings. It is then important to ensure that the occupants survive an impact with water in an adequate physical condition in order to make good their escape. This can be achieved by introducing crashworthy airframes and seats, improving occupant restraint systems and investigating the optimum brace position for individual seats.

Having survived the ditching the next immediate requirement is for the helicopter to remain upright and on the surface for sufficient time for the occupants to evacuate safely. If it does invert or sink, then the occupants should be provided with a simple means of escape, aided by underwater escape lighting, breathing devices, easily operated escape hatches and a minimum risk of clothing or equipment snagging. Additionally, they should be fully educated in the complications caused by inrushing water, disorientation, cold water immersion and inherent buoyancy of clothing.

This report summarises the developments for safe underwater escape and identifies areas of concern. Recommendations are made tor future human factors work to improve the chances of survival for aircrew involved in helicopter ditchings.