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 is often given if the aircraft must make an emergency landing over land or water.
Types of brace positions
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:
- 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, following the Kegworth air disaster in 1989, the UK Civil Aviation Authority
contracted an engineering consultancy, Hawtal Whiting Structures, to
perform computer based analytical investigation to optimise the brace
for impact position for forward-facing passengers. This was supported by
medical information from the University of Nottingham and testing at
the Institute of Aviation Medicine.
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.
Most experts will say that maximum protection for a forward-facing
seat is when the passenger is able to pre-position their head on the
surface they are likely to impact (e.g., seat back or bulkhead), as the
risk of head trauma is significantly reduced during the crash. Reducing
head trauma may also help the passenger stay conscious, which is also
essential for rapid evacuation after the crash.
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 exactly the same but
with the feet behind the knees, with some airlines requiring 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 and 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.
Myths
There have been myths surrounding the use of the brace procedure,
namely 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. Instances where the brace procedure has
been adopted have been shown to save lives. In one accident, passengers
were asleep on an aircraft that was about to collide with trees. One
passenger, out of the sixteen, awoke and adopted the procedure, and he
was the only survivor. All passengers aboard Scandinavian Airlines Flight 751,
which crashed, survived: an outcome which it has been suggested was
largely thanks to the passengers' universal adoption of the brace
position.
During the "Miracle on the Hudson" flight on January 15, 2009, there were fewer than three minutes to land U.S. Airways Flight 1549 into the Hudson River
and the only words the passengers heard from the pilot were "Brace for
Impact". Flight attendants chanted, "Brace! Brace! Heads down! Stay
down!" and all 155 people on board survived with no life-threatening injuries.
Safety cards
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, such as a 1993 ruling by the United Kingdom Civil Aviation Authority (issued in a Notice to Air Operator Certificate Holders 1993) or, for example, in CAO 020.11 (section 14.1.3), issued by the Civil Aviation Safety Authority of Australia.
The depiction of how to adopt the brace position is not a basic standard set forth by the International Civil Aviation Organization. While many regulatory bodies have adopted this addition on their own (as noted above), the FAA has not required it on flights to, from, or within the United States.
Planned or unplanned crash landings
In an unexpected emergency on a passenger aircraft where an impact may
be possible, cabin crew are trained to recognize such situations (e.g.,
flight attendants sense that the take-off is not going as usual) and
shout commands to passengers, such as "Bend over! Stay down!", "Brace
for impact! Prepare for Crash- Landing,Prepare for Crash- Landing! Heads
down! Stay down!" or "Brace! Brace!" In a developing emergency, the
cabin crew can first give a briefing to passengers on how to properly
adopt the brace position. Before the emergency landing, the flight deck
usually gives a pre-arranged signal (such as the command, "Brace for
impact." over the public announcement system or flashing the fasten
seat-belt sign several times), whereupon the cabin crew will shout
commands to passengers to adopt the brace position, such as "Brace,
Brace! Stay down!" or "Get your heads down, stay down!", Which the cabin
crew is required to chant repeatedly in a loud voice until the aircraft
comes to a complete stop or they receive an "evacuate" command. Every airline has their own command when commanding passengers to take the brace position.
Kegworth
In the 1989 Boeing 737-400 Kegworth air disaster
crash, the pilot was able to announce "Prepare for crash landing" 10
seconds before impact; the resulting injuries—from both those who did
and did not adopt the brace position—would later be studied to provide
further research on this topic. A CAA-funded engineering–medical joint
research team was established, led by Nigel Rock of Hawtal Whiting (HW)
Engineering Consultants and Prof Angus Wallace
of the Nottingham University Hospital. The team was aided by Wg Cdr
David Anton of the Royal Air Force 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.)
Source:
http://en.wikipedia.org/wiki/Brace_position
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