Punctured pressure cabin.

From: "Emmanuel.Gustin"

B2431 wrote:

: I agree a big chunk of skin suddenly departing the aircraft can cause major
: damage and fatalities like the Hawaii Air stewardess deplaning prematurely.
: There was also a case in the 1970s of a DC-10(?) where the aft cargo hatch
blew
: and took a row or two of seats with it.

IIRC there have been incidents with the cargo hatches of DC-10s,
but not limited to the loss of a number of seats; the entire
aircraft was lost --- depressurisation of the cargo bay
caused the cabin floor to collapse, destroying the control
runs.

As a result, modern aircraft were designed to have vents around
the cabin floor.

Emmanuel Gustin


You are correct. The only one I could think of off the top of my head was where
the last row or two caved. I don't recall if the aircraft landed safely. If
memory serves it occurred near or over Turkey.

Dan, U.S. Air Force, retired

From: Cub Driver
Date: 1/1/2004 5:06 AM Central Standard Time
Message-id:


Another question is if the terrorist is female will she still get the 72
virgins when she is "martyred?"

Perhaps she gets multiplied into 72 virgins.
all the best -- Dan Ford
email:

OK, if she dies a virgin does her obituary say "returned unopened?"

Dan, U.S. Air Force, retired

"B2431" wrote in message
...
| From: Cub Driver
| Date: 1/1/2004 5:06 AM Central Standard Time
| Message-id:
|
|
| Another question is if the terrorist is female will she still get the 72
| virgins when she is "martyred?"
|
| Perhaps she gets multiplied into 72 virgins.
| all the best -- Dan Ford
| email:
|
| OK, if she dies a virgin does her obituary say "returned unopened?"
|
| Dan, U.S. Air Force, retired





Opened in error ?






Cheers


Dave Kearton

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.


--
Emmanuel Gustin

In article ,
"Emmanuel.Gustin" wrote:

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.

No one is ever going to be able to hijack an airliner anywhere in the
world any more and expect people to believe that they're merely going to
hold the passengers and plane hostage.

The stakes have been upped to the max for all future hijack attempts,
and nobody can *afford* to assume "good" motives by anyone who tries to
take over a plane, *ever*.

From here on out, a hijack attempt will, by any rational person, be
treated as an attempt at mass murder. If you want to make a political
statement, hijack a ferry or a bus.

--
cirby at cfl.rr.com

Remember: Objects in rearview mirror may be hallucinations.
Slam on brakes accordingly.

"B2431" wrote in message
...
From: "Kevin Brooks"
Date: 1/1/2004 1:01 AM Central Standard Time
Message-id:


"B2431" wrote in message
...
From: Cub Driver

snip

As to the possibility of explosive decompression, as I understand the
matter, it could happen if a bullet fractured a window

It would still be only annoying. A few ear aches and a lot of noise
along
with
oxygen masks dropping. The person sitting next to the window might lose
his
reading material or dinner.

This has been discussed here before and a Google search would turn up a
lot of
information.

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.


I agree a big chunk of skin suddenly departing the aircraft can cause
major
damage and fatalities like the Hawaii Air stewardess deplaning
prematurely.
There was also a case in the 1970s of a DC-10(?) where the aft cargo hatch
blew
and took a row or two of seats with it.

Two windows is not a big chunk of skin. Neither was the Piedmont accident a
"big chunk of skin", and a passenger still died.


On the other hand in the late 1980s a C-141B departed Eglin AFB and a
hatch
over the cargo compartment blew. One of my men was standing directly below
it
at the time. He noticed sudden day light, very loud noise and a bit of
pain. I
believe the aircraft was at approximately 30 kilofeet at the time. It
returned
to Eglin, made a safe landing and everyone sent to the base hospital for
evaluation.

A cargo hatch blew out of a DC-10 in 1974, and it took a big chunk of the
cabin floor above, with passengers, out of the aircraft--the rest of the
aircraft then augered in. Face it, rapid decompression *can* (does not mean
*will be*) be a very bad thing, even when it may just involve a window.

Brooks


Dan, U. S. Air Force, retired

"B2431" wrote in message
...
From: "Emmanuel.Gustin"

B2431 wrote:

: I agree a big chunk of skin suddenly departing the aircraft can cause
major
: damage and fatalities like the Hawaii Air stewardess deplaning
prematurely.
: There was also a case in the 1970s of a DC-10(?) where the aft cargo
hatch
blew
: and took a row or two of seats with it.

IIRC there have been incidents with the cargo hatches of DC-10s,
but not limited to the loss of a number of seats; the entire
aircraft was lost --- depressurisation of the cargo bay
caused the cabin floor to collapse, destroying the control
runs.

As a result, modern aircraft were designed to have vents around
the cabin floor.

Emmanuel Gustin


You are correct. The only one I could think of off the top of my head was
where
the last row or two caved. I don't recall if the aircraft landed safely.
If
memory serves it occurred near or over Turkey.

It went down (occured in '74). ISTR another incident over Japan with similar
results?

Brooks

Dan, U.S. Air Force, retired

"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.

Again I say: fasten your seat-belt when flying!

You must have missed the rest of the message where I acknowledged that the
decompression threat did not outweigh the threat from hijacker(s).

Brooks


all the best -- Dan Ford

"Cub Driver" wrote in message
...

A normal bullet hole would be no problem. There's already a much
larger vent to the outside, which stabilizes cabin pressure against
the fresh & heated air being pumped in from the engines. People
smarter than I say that this hole is about three inches in diameter.

More detail on this: over on rec.aviation.piloting, there's a parallel
and very busy thread on this same subject. Here's what a Big Spam Can
Driver had to say on the subject of the vent hole(s):

"Actually, a little bigger. There are two outflow valves that work in
tandem. On the 747 they're located on the aft belly, and each is a
touch smaller in area than one aircraft window -- an oval about 4in by
12in. There are also two relief valves on the left side of the
airplane, and they are about 8" in diameter."

So upon reflection it doesn't seem that even the blow-out of a window
could cause more than terror and discomfort, especially since it would
almost certainly be followed by an emergency descent to lower
altitude.

That is the problem with overgeneralization--it is usually wrong. It "could"
indeed cause more than terror and discomfort. The Brazilian airliner lost a
passenger when it had two windows taken out; a Piedmont airliner suffered a
passenger fatality during a rapid decompression that did not involve any
large opening at all. Having been through a few nasty eardrum ruptures, I
can tell you that the pain involved adds up to a bit more than "discomfort"
(when blood and pus are ejected a couple of inches out of the ear you can
imagine the sensation involved)--the passengers on that Aer Lingus 737 might
attest to that.

Brooks


One of the pilots commented: "I always wear my seat-belt when flying.
Don't you?" Something to add to your resolutions for 2004


all the best -- Dan Ford
email:

see the Warbird's Forum at www.warbirdforum.com
and the Piper Cub Forum at www.pipercubforum.com

"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