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Wednesday, February 28, 2018

Plane crash survival - Will the Brace position kill you? - YouTube
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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.


Video Brace position



Types of brace position

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.

Forward-facing seat

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

  • Placing the head on, or as close as possible to, the surface it is most likely to strike. (For example, the bulkhead or seat in front.)
  • Having the passenger lean over to some degree to avoid jackknifing or submarining.
  • Placing the feet flat on the floor.

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.

The brace procedure for the forward-facing seat in the United States is similar to that of the UK, but rather than placing the hands on the back of the head, passengers are advised to place them on the top of the seat in front, one hand holding the other wrist and resting the head in the space between the arms. If the seat in front is not within reach then passengers are advised to either grab their ankles or place their hands under their legs and grab the opposite forearm.

Jumpseats

Flight attendant brace positions are somewhat different due to the design of aircraft jumpseats. So far, there has been little research into the best brace position for flight attendants, though airlines have adopted positions that are very similar to one another.

In rear-facing seats, the attendant should be sitting with their back and head firmly against the back of the jumpseat, their knees and feet together and slightly in front of or behind the knee (depending on the individual airlines procedures)--commonly referred to as "toes to tail". In European carriers, the hands can be placed behind the head and hands one on top of the other and the elbows brought in to meet, taking care that the forearm does not cover the ear and restrict hearing. This position provides the flight attendant protection to the face from any flying debris (as it will impact their elbows) yet still provides them with the ability to view the cabin and not muffle their commands. In the United States, the Federal Aviation Administration (FAA) does not recommend placing the hands behind the neck as their research suggests such actions can cause unnecessary loading on the neck and spine during an impact. Instead, US flight attendants are typically taught to sit on their hands, palms facing the ceiling, underneath their upper legs. Other variations include clasping the hands on the knees or using one arm to "hug" the opposing arm.

For forward-facing jumpseats, the position is the same but with the feet behind the knees. Some airlines also require flight attendants to tuck their chin in to their chest ("bow to the captain") to reduce the likelihood of whiplash injuries.

There is also a third brace position for flight attendants, and that is the "normal" brace position. This is adopted by the attendant for every take-off and landing; it provides them with protection from any sudden emergencies and allows them to adopt the full brace position quickly should they need to. The only difference between the normal brace and the full brace position is that the attendants will either fold their arms across their stomach or immobilize them by placing their hands under their thighs with the palms up. This position forms part of every flight attendant's sixty second review--a technique being adopted by airlines whereby the attendant will go over various factors in their head during the take-off and landing sequence. Things such as "how do I open my door?", "where is the next nearest exit?", "am I over land or water?" and "what commands will I shout" are just a few of the questions an attendant will ask themselves. The belief is that this mental review focuses the attendant on the safety-critical role they have during take-off and landing and will result in faster decision-making and adaptation to the scenario.

Newer brace positions are being adopted by many U.S. airlines in which the flight attendants do not sit on their hands. Instead, they place their hands flat on top of their thighs. This new position is being adopted because in the event of a crash, sitting on hands can cause injury and/or crushing.

Infants

If carrying an infant on a lap, it is generally recommended that above positions should be adopted as best as possible, cradling the child with one arm and using this to also protect the child's head. In the UK, lap children are instructed to wear an infant safety belt which is a separate seat belt with a loop that connects to the parent's belt; however, in the United States such belts are not permitted by FAA regulations. The FAA believes that such baby belts significantly increases the risk of injury to the child. In the early era of commercial aviation, the recommended brace position for children was on the floor against a bulkhead; this has since been amended due to the position's lack of protection. The safest position for an infant is in an aviation certified child safety seat.


Maps Brace position



Instruction

Routine instruction

Many government aviation administrations or regulatory bodies mandate the depiction of how to adopt the brace position on aircraft safety cards and in-flight safety demonstrations. Examples are a 1993 ruling by the United Kingdom Civil Aviation Authority (issued in a Notice to Air Operator Certificate Holders 1993) and CAO 020.11 (section 14.1.3) issued by the Civil Aviation Safety Authority of Australia. The FAA has not required this instruction on flights to, from, or within the United States.

The depiction of how to adopt the brace position is not a basic standard set forth by the International Civil Aviation Organization.

Before crash landings

The cabin crew on a passenger aircraft are integral to getting passengers to assume positions. If time allows in a developing emergency, the cabin crew can brief passengers on how to properly adopt the brace position. Cabin crew are also trained to recognize emergency situations where an impact may be possible (for example, flight attendants sense that the take-off is not going as usual). Immediately before the emergency landing, the flight deck usually gives a pre-arranged signal (such as the command "Brace for impact" or "Cabin crew and passengers, brace brace." over the public announcement system or flashing the fasten seat-belt sign several times), whereupon the cabin crew shouts commands to passengers and repeat until the plane has safely landed on the ground. Every airline has their own command; examples include

  • "Bend over! Stay down!"
  • "Brace for impact! Prepare for crash-landing, prepare for crash-landing! Heads down! Stay down!"
  • "Brace!" (repeated until the aircraft lands.)
  • "Brace! Brace! Stay down!"
  • "Brace, brace! Heads down, grab your ankles!"
  • "Brace! Brace! Brace! Heads down! Stay down!"
  • "Get your heads down, stay down!"
  • "Heads down, grab ankles, stay down."
  • "Heads down feet back! Heads down feet back!"
  • "Heads down! Stay down!"
  • "Bend down! Böj ner!" (Airlines in the Scandinavian countries repeat the Bend down-phrase in a Scandinavian language, alternating between the two languages.)


The cabin crew repeatedly chants the instructions in loud voices until the aircraft comes to a complete stop or they receive an "evacuate" command. The above commands differ according to whether passengers have been briefed as to what do to when they hear the brace command or not. Usually, the command "Brace, brace" is given only when passengers have been briefed about the emergency landing. Otherwise, the command usually refers to the specific indications on how to take the brace position (head down, stay down, etc.).


Closeup of an airline safety card showing the
src: c8.alamy.com


Myths

There have been myths surrounding the use of the brace procedure. One is that adopting the brace procedure is only useful for preserving dental integrity for identification after a crash; another myth is that the position is designed to increase the chance of death to reduce insurance-paid medical cost. These myths have been debunked with evidence that the brace position "does indeed work to preserve lives in an air disaster."


Closeup of an airline safety card showing the
src: c8.alamy.com


Successful use

In instances where the brace procedure has been adopted, injuries are reduced and lives are saved. In one accident, sixteen passengers were asleep on a twin-engined aircraft that was about to collide with trees. One passenger awoke, braced himself, and was the only survivor. When Scandinavian Airlines Flight 751 crashed in 1991, all passengers aboard survived; a "significant factor" to this outcome was the passengers' universal adoption of the brace position. During the "Miracle on the Hudson" emergency water landing of US Airways Flight 1549 in 2009, the pilot warned "Brace for Impact" and flight attendants chanted, "Brace! Brace! Heads down! Stay down!" All 155 people on board survived with no life-threatening injuries. In a press interview, one of the surviving crew members of LaMia Flight 2933 said that he survived because he followed the emergency protocols by putting his carry-on suitcase between his legs and sitting in the brace position.


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Notes


Closeup of an airline safety card showing the
src: c8.alamy.com


Further reading

  • HW Structures: Rock N, Haidar RCAA Paper 90012 Occupant modelling in aircraft crash conditions: Civil Aviation Authority, 1990, ISBN 0-86039-445-X.
  • White BD, Firth JL, Rowles JM. "The effects of brace position on injuries sustained in the M1 Boeing 737/400 disaster, January 1989". NLDB Study Group. Aviat Space Environ Med. 1993 Feb;64(2):103-9.
  • Hawtal Whiting Technology Group: Rock N, Haidar R, CAA Paper 95004 A study of aircraft passenger brace positions for impact: Civil Aviation Authority, 1995, ISBN 0-86039-620-7.
  • Brownson P, Wallace WA, Anton DJ. "A modified crash brace position for aircraft passengers." Aviat Space Environ Med. 1998 Oct;69(10):975-8.

Source of article : Wikipedia