Punctured pressure cabin.

From: "Pete"
Date: 1/1/2004 10:12 AM Central Standard Time
Message-id:


"Cub Driver" wrote in message
.. .

Dan, you are forgetting that there was indeed documented evidence of a
passenger being sucked out of a blown window brought out during that
discussion--a TAM Fokker F28 turboprop somwhere over Brazil

I'd rather give up the guy in the window seat than go down with the
airplane onto Times Square.

Put fat people in the window seats. Maybe they can serve as a plug, and save
the rest of us.

Pete


Pete, I happen to be fat and I do sit near the windows. If you were sitting
near me and the window blew I'd seriously consider plugging it with your rude
body.

Dan, U. S. Air Force, retired

From: Cub Driver
Date: 1/1/2004 2:00 PM Central Standard Time
Message-id:

FWIW, tomorrow (Friday) night on The Discovery Channel's "Myth Busters"
program, one of their projects is rapid decomp of an airliner.

Will somebody summarize the findings here, for the sake of us pathetic
losers with antennas in the attic?

all the best -- Dan Ford
email:


The urban myth in question was that a passenger heard a funny noise coming from
the window. He summoned a stewardess who leaned forward to listen and was blown
through the window when it blew. Supposedly she exited the window like
"toothpaste from a tube."

The show has experts, altitude chambers etc all of which proved it could never
happen.

Dan, U. S. Air Force, retired

Emmanuel.Gustin wrote:
M. J. Powell wrote:

: There has been a bit of a furore over here concerning the new US
: requirement to airlines to supply air marshals when requested. The
: concern is mainly over the possible puncture of a pressure cabin.
: What do readers think is the result of decompression via a bullet hole?

A bullet hole would not in itself cause for much concern.
The loss of a cabin window would be more serious, not
because the pressurisation system would be unable to cope,
but because the strong air current could move (in the worst
case, blow out through the window) or wound passengers. In
extreme cases, rapid pressure loss (or perhaps
more accurately, an internal pressure differential) can
lead to major structural failures, especially around
bulkheads that are insufficiently vented -- the pressure
differential is enough to make these collapse -- or in
fuselages that are already 'tired'. Apart from the Comet
disasters, I know of no loss of aircraft caused by the
loss of windows (although some passengers have been lost)
but a number of aircraft have been lost when doors failed.

There is also the risk of bullets bouncing around inside
the plane and doing damage to power lines, fuel systems,
etc. Historically, fire has been the major killer of
aircraft following projectile damage.

Seems to me that although loss of cabin pressure is serious
concern (IIRC military aircraft were designed to maintain
lower cabin pressure than airliners, to limit the damage
amplification following a hit) but not the most serious one.
The worst problem is the prospect of a gun battle in a cabin
packed with people. Almost every stray bullet is going to
hit someone; even if the sky marshall hits the right man
(or woman) the bullet seems likely to hit others as well.

This is going to require very fine judgment by the sky
marshall. He or she also has to distinguish between a
conventional hijack best dealt with by negotiation (are
sky marshalls trained to conduct hostage-release
negotiations?) which are the vast majority of cases,
and a rare attempt to use an airliner as a suicide bomb.
This seems to be a job requiring very extensive training,
a very cool head, and fine judgment. I am not convinced
that the large number of sky marshalls rapidly trained
and deployed now have the right capabilities, and I don't
think it is wise at all to give guns to pilots after
minimal training.

You have touched a sore spot here on this last point. You seem
to be under the impression that there might be "conventional"
highjackings. These are a thing of the past. The minute that
passengers and cabin crew subdued Richard Reid, it was clear that
"conventional" highjackings, were no longer. There is no negotiation
skill required. Kill anyone that is attempting to commandeer an
aircraft. Time has to be divided into pre 9/11 and post 9/11. Your
statement applies to pre 9/11 highjackings only. The judgement required
of the sky marshal--- Is this person an unruly/drunk passenger, or is he
intent on mischief. If he is a drunk, or unruly passenger, subdue, and
restrain him. If he (or she) is intent on mischief, deadly force is
mandatory.
KenG

Thanks, you said what I should have.

B2431 wrote:

From: "Pete"
Date: 1/1/2004 10:12 AM Central Standard Time
Message-id:


"Cub Driver" wrote in message
. ..

Dan, you are forgetting that there was indeed documented evidence of a
passenger being sucked out of a blown window brought out during that
discussion--a TAM Fokker F28 turboprop somwhere over Brazil

I'd rather give up the guy in the window seat than go down with the
airplane onto Times Square.

Put fat people in the window seats. Maybe they can serve as a plug, and save
the rest of us.

Pete



Pete, I happen to be fat and I do sit near the windows. If you were sitting
near me and the window blew I'd seriously consider plugging it with your rude
body.

Dan, U. S. Air Force, retired

"Emmanuel Gustin" wrote...

Probably not. I would be more worried about bullets striking
cabling and causing short-circuits.

They're all protected by circuit breakers. Any fire would be short lived.


The vast majority of hijacks have not ended in crashes, but in
safe landings, and were resolved on the ground by negotiation
if possible, and in the worst case by security forces storming
the plane.

Sorry, but the past is no indicator of the future in this case. The events of
9-11 have proven beyond ANY doubt that NO airborne hijacker can be allowed into
ANY cockpit for ANY reason EVER AGAIN! There is NO reason to believe ANY
hijacker will have ANY purpose but similar acts of mass destruction!


The presence of sky marshalls can have a certain deterrent
effect, but I doubt their effectiveness in a real incident.

They have already proven effective in several incidents.


Considering the layout of most large airliners, it would be
difficult enough for the officer to remain aware of what is
happening (the pilot can signal that there is an attempt to take
control of the aircraft, but probably little else)

If a sky marshall is so "out of it" that he is not aware that a hijacker has
passed him and is at the cockpit door, attempting entry, he is probably already
dead. In that case, the pilots DO have options to try to prevent entry. If
those fail, their weapons may be the only alternative.


It's sound like a promising theoretical concept, but I think the
money and resources would be far better spent on measures
to prevent terrorists getting on board.

So far, all of them have failed.


It is, as far as I know, only one week. Far too little to deal
with a complex and psychologically very demanding situation,
in which pilots would be dealing with pressure exerted on them
from the other side of a closed door, while the terrorists hold
the passengers hostage. The notion that the pilots could defend
the cockpit as a kind of fortress seems far too simplistic to me.

Well, I guess you aren't an airline pilot, then...

On Thu, 01 Jan 2004 15:15:30 -0500, Cub Driver
wrote:


I don't
think it is wise at all to give guns to pilots after
minimal training.

First, the training is NOT "minimal"! It is intense and specialized.

Most American pilots now flying were trained in the military.

I think you're still safe if you say "many" or "over half", but not
"most". The demographics have changed markedly, with new hires being
about 70% civil only for the last decade or so.

Furthermore, most American men have used firearms at one time or
another.

Are you sure about this? And what about women pilots?

Mary

--
Mary Shafer Retired aerospace research engineer

"Cub Driver" wrote...

(IIRC military aircraft were designed to maintain
lower cabin pressure than airliners, to limit the damage
amplification following a hit)

I was pondering this possibility also, but then I remembered that the
B-36 was supposed to be *depressurized* when the plane moved into a
combat situation.

For a couple data points, the A-4 and A-6 had cabin pressure differentials of
about 4 and 5 psi (8,000' cockpit at about 23,000'). There was no
depressurization procedure for combat. The 747-400 runs normally at 8.9 psi
(6,700' cabin at about 43,000').

The B-36 was an early pressurized aircraft, developed during war time. I
suspect engineers' knowledge of the aircraft reaction to combat damage and rapid
depressurization was a lot less than now...

"B2431" wrote in message
...
From: "Kevin Brooks"

snip

Dan, you are forgetting that there was indeed documented evidence of a
passenger being sucked out of a blown window brought out during that
discussion--a TAM Fokker F28 turboprop somwhere over Brazil (see:
www.crashdatabase.com/cgi-bin/
webdata_crashdatabase.cgi?cgifunction=Search&Airl ine=%5ETAM%24 ).
There
was
also a fatality during a 1989 Piedmont Airlines 737 rapid
decompression
(www.canard.com/ntsb/ATL/89A099.htm ). As to the non-fatal effexcts,
the
experience of an Aer Lingus 737 tends to point to some rather
significant
injuries during a 1999 depressurization accident, with lots of
ruptured
eardrums and severe nosebleeds, etc. I would not disagree that these
potential problems are far outweighed by the threat of some whacko
with a
knife/bomb/etc., said whacko being dispatched by an air marshal, even
with
the remote potential of causing a rapid decompression being
preferrable
to
the alternative. But the effect of such a decompression is likely
going
to a
bit worse than cleaning your tray table off and causing a few
earaches.

Brooks



Dan, U. S. Air Force, retired

I was referring to the blown out window. The passenger you refer to was
blown
out a six foot hole according to your cite.

Heh? "Pressurization was lost at an altitude of 33,000 feet when the
right
engine disintegrated, causing pieces of the engine to break two cabin
windows." That does not a six foot hole equal.

OK, mia culpa, I was reading the incident just below the flight to which
you
referred.

In the incident you cite I wonder what he actually died of considering the
only
other injuries were "minor." Heart attack maybe?

I think you are mixing up the *two* incidents I cited specifically. In the
one you are discussing involving the windows blowing out (TAM F-28 over
Brazil), the fatality left the aircraft rather abruptly via one of those
windows, from what I gathered based upon looking at a few sources. The other
fatality occured on a Piedmont 737, which underwent an unspecified rapid
decompression with the one individual later dying at the hospital--I would
imagine likely heart or respiratory failure, or a combination thereof.

Brooks

Dan, U. S. Air Force, retired

"B2431" wrote in message
...
From: Cub Driver
Date: 1/1/2004 2:00 PM Central Standard Time
Message-id:

FWIW, tomorrow (Friday) night on The Discovery Channel's "Myth Busters"
program, one of their projects is rapid decomp of an airliner.

Will somebody summarize the findings here, for the sake of us pathetic
losers with antennas in the attic?

all the best -- Dan Ford
email:


The urban myth in question was that a passenger heard a funny noise coming
from
the window. He summoned a stewardess who leaned forward to listen and was
blown
through the window when it blew. Supposedly she exited the window like
"toothpaste from a tube."

The show has experts, altitude chambers etc all of which proved it could
never
happen.

I would take the TAM F-28 accident as a departure from that "could not
happen". Unlikely, yes; impossible, no, as we have already seen. I keep
racking my head for the info regarding an incident back in the 80's where a
USAF C-130 (or maybe EC-130) was fired upon by a Columbian or Venezuelan
fighter (mistaken identity case), and IIRC a crewmember of the Herky Bird
was ejected from the aircraft...?

Brooks


Dan, U. S. Air Force, retired

"John R Weiss" wrote in message
news:NJ1Jb.24583$I07.64369@attbi_s53...
"Cub Driver" wrote...

(IIRC military aircraft were designed to maintain
lower cabin pressure than airliners, to limit the damage
amplification following a hit)

I was pondering this possibility also, but then I remembered that the
B-36 was supposed to be *depressurized* when the plane moved into a
combat situation.

For a couple data points, the A-4 and A-6 had cabin pressure differentials
of
about 4 and 5 psi (8,000' cockpit at about 23,000'). There was no
depressurization procedure for combat. The 747-400 runs normally at 8.9
psi
(6,700' cabin at about 43,000').

The B-36 was an early pressurized aircraft, developed during war time. I
suspect engineers' knowledge of the aircraft reaction to combat damage and
rapid
depressurization was a lot less than now...

I wonder where this depressurization before entering combat thing came from?
IIRC my father never mentioned any routine depressurization during the
combat missions he pulled during WWII on the even earlier designed B-29.

Brooks