Brace position

To assume a brace or crash position is an instruction that can be given to prepare for a crash, such as on an aircraft; the instruction to 'brace for impact!' or 'brace! brace!' is often given if the aircraft must make an emergency landing over land or water.

There are many different ways to adopt the brace position, with many countries adopting their own version based on research performed by their own aviation authority or that of other countries. There is commonality among all brace positions despite these variations.

For a forward seated passenger wearing only a lap belt, common recommendations for the brace position include:

In the United Kingdom, the brace-for-impact position for forward-facing passengers was optimised following the Kegworth air disaster in 1989. In that incident, the pilot announced "Prepare for crash landing" 10 seconds before impact, and the resulting injuries—from both those who did and did not adopt the brace position—would later be studied. The UK Civil Aviation Authority funded an engineering–medical joint research team, led by Nigel Rock of Hawtal Whiting Engineering Consultants and Prof. Angus Wallace of the Nottingham University Hospital and aided by Wg Cdr David Anton of the Royal Air Force Institute of Aviation Medicine. Crash data was supplemented by medical information from the University of Nottingham and testing at the Institute of Aviation Medicine. The work used mathematical modelling derived from the automobile industry to analyse the human body under crash conditions. (See "Further reading" below.)

This work led to the formation of the International Board for Research into Aircraft Crash Events (IBRACE) on 21 November 2016.

The brace position as set out to airlines in the UK for passengers in forward-facing seats is based on extensive analytical work arising from Kegworth. It is subtly different from that in the United States and some other countries. Passengers should place their feet and knees together with their feet firmly on the floor (either flat or on the balls of their feet) and tucked behind the knees to prevent shins and legs from being broken against the base of the seat in front. They should bend as far forward as possible, resting their head against the seat in front if it is within reach and place their hands on the back of their head, with the hands one on top of another (rather than interlocked). Their elbows should then be brought in. This prevents both flailing of the arms in the crash sequence and protects the head from flying debris. The head should be as far below the top of the seats as possible to prevent injury from any collapsing overhead compartments.

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Wikipedia