Mythbusters Explosive Decompression Experiment

Now, that was cool!

Mythbusters pressurized an old DC-9 and fired a bullet through the wall to
see if it would cause an explosive decompression. It didn't. Then they fired
a bullet through the window to see if the window would shatter and cause an
explosive decompression. The bullet only made a small hole in the window
because the windows are made of shatter-proof plastic. No explosive
decompression.

Then Mythbusters put explosive all around the window to blow it out and
deliberately cause an explosive decompression. The crash test dummy,
"Buster," was damaged but was not sucked out the window. If he had been a
real person he would have been injured but probably lived. His arm was badly
damaged enough that a human arm might have been lost. So Mythbusters patched
everything up and used a shaped charge to blow out the whole wall. The
explosive decompression ripped the entire top off the fuselage and much of
the wall out, but the seats and the crash test dummy remained in the
airplane. I would guess that if the "Buster" had been a live human he would
have been seriously injured and possibly killed.

Mythbusters then talked about how strong these airplanes really are and
closed with photos of the Hawaiian Airlines plane that suffered an explosive
decompression similar to the one that the show created with a shaped charge.
The only person killed was a flight attendant who was pulled from the plane
by the airstream, but the passengers all survived.

I thought the show was fascinating. It really demonstrated the engineering
that goes into an airliner. Besides, I like watching things blow up. It must
appeal to my inner 12 year old.

--
Christopher J. Campbell
World Famous Flight Instructor
Port Orchard, WA


If you go around beating the Bush, don't complain if you rile the animals.

"C J Campbell" wrote in message
...

Mythbusters then talked about how strong these airplanes really are and
closed with photos of the Hawaiian Airlines plane that suffered an
explosive
decompression similar to the one that the show created with a shaped
charge.
The only person killed was a flight attendant who was pulled from the
plane
by the airstream, but the passengers all survived.

However, at one of the passengers soon after gave birth to a little girl who
died a day later. There was no particular pathology. Milagro they called
her. She was my sister-in-law's niece.

I'm not blaming anyone - if anything I just wanted to honor her memory.

-- David Brooks

Neonates do die, fortunately not with great frequency... As a working doc I
immediately wondered about Caisson Disease from the rapid decompression,
when I read your posting... The fetus is normally well protected and
buffered by the body of the mother for trauma like that... And, the total
psi/bar drop in that form of decompression is minor compared to divers, et.
al., however the rate of change of the decompression is far more
instantaneous than for caisson workers and divers, so if it was Caisson
Disease the rate of change had to be the key..

Denny
"David Brooks"
However, at one of the passengers soon after gave birth to a little girl
who
died a day later. There was no particular pathology. Milagro they called
her. She was my sister-in-law's niece.

On Mon, 12 Jan 2004 08:26:04 -0500 "Dennis O'Connor" wrote:

Neonates do die, fortunately not with great frequency... As a working doc I
immediately wondered about Caisson Disease from the rapid decompression,
when I read your posting... The fetus is normally well protected and
buffered by the body of the mother for trauma like that... And, the total
psi/bar drop in that form of decompression is minor compared to divers, et.
al., however the rate of change of the decompression is far more
instantaneous than for caisson workers and divers, so if it was Caisson
Disease the rate of change had to be the key..


If that were true others on board would also have suffered from "the bends".
If the mother was severly traumatized (and who wouldn't have been) then
that could easily have caused complications. Sever emotional trauma sets
off a chain reaction of chemical events in the body. They are designed
to protect but it could have been too stressful for the baby.


R. Hubbell


Denny
"David Brooks"
However, at one of the passengers soon after gave birth to a little girl
who
died a day later. There was no particular pathology. Milagro they called
her. She was my sister-in-law's niece.

Now, that was cool!

Agreed. The ten minutes I caught at the end were very well done, and should
go a long way toward dispelling the myth.

Now if only they had a more significant viewership...
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

There is no problem so vexing as cannot be solved by application of
sufficient explosives...

"C J Campbell" wrote in message
...
Now, that was cool!

"C J Campbell" wrote in message ...
Now, that was cool!

Mythbusters pressurized an old DC-9 and fired a bullet through the wall to
see if it would cause an explosive decompression. It didn't. Then they fired
a bullet through the window to see if the window would shatter and cause an
explosive decompression. The bullet only made a small hole in the window
because the windows are made of shatter-proof plastic. No explosive
decompression.

Then Mythbusters put explosive all around the window to blow it out and
deliberately cause an explosive decompression. The crash test dummy,
"Buster," was damaged but was not sucked out the window. If he had been a
real person he would have been injured but probably lived. His arm was badly
damaged enough that a human arm might have been lost. So Mythbusters patched
everything up and used a shaped charge to blow out the whole wall. The
explosive decompression ripped the entire top off the fuselage and much of
the wall out, but the seats and the crash test dummy remained in the
airplane. I would guess that if the "Buster" had been a live human he would
have been seriously injured and possibly killed.

Mythbusters then talked about how strong these airplanes really are and
closed with photos of the Hawaiian Airlines plane that suffered an explosive
decompression similar to the one that the show created with a shaped charge.
The only person killed was a flight attendant who was pulled from the plane
by the airstream, but the passengers all survived.

I thought the show was fascinating. It really demonstrated the engineering
that goes into an airliner. Besides, I like watching things blow up. It must
appeal to my inner 12 year old.

I also watched the show and one factor they did not take into account
was the speed of an airliner at altitude. Also, what would happen to
the forces on the damnaged airframe during the descent/emergancy
landing? As in most tests, this was a controlled experiment. I'm sure
if they placed the shaped charge closer to the wing root, more
damnaged would occure.

Still a good show, I especially like the part where they used a 22
bullet for a fuse replacement.

The speed of the airplane at altitude has nothing to do with it. The
pressure differential between the cabin and the great outdoors is the only
factor...airspeed does not exert any pressure on the sides of the fuselage.

Bob Gardner

"Mark" wrote in message
om...
"C J Campbell" wrote in message
...
Now, that was cool!

Mythbusters pressurized an old DC-9 and fired a bullet through the wall
to
see if it would cause an explosive decompression. It didn't. Then they
fired
a bullet through the window to see if the window would shatter and cause
an
explosive decompression. The bullet only made a small hole in the window
because the windows are made of shatter-proof plastic. No explosive
decompression.

Then Mythbusters put explosive all around the window to blow it out and
deliberately cause an explosive decompression. The crash test dummy,
"Buster," was damaged but was not sucked out the window. If he had been
a
real person he would have been injured but probably lived. His arm was
badly
damaged enough that a human arm might have been lost. So Mythbusters
patched
everything up and used a shaped charge to blow out the whole wall. The
explosive decompression ripped the entire top off the fuselage and much
of
the wall out, but the seats and the crash test dummy remained in the
airplane. I would guess that if the "Buster" had been a live human he
would
have been seriously injured and possibly killed.

Mythbusters then talked about how strong these airplanes really are and
closed with photos of the Hawaiian Airlines plane that suffered an
explosive
decompression similar to the one that the show created with a shaped
charge.
The only person killed was a flight attendant who was pulled from the
plane
by the airstream, but the passengers all survived.

I thought the show was fascinating. It really demonstrated the
engineering
that goes into an airliner. Besides, I like watching things blow up. It
must
appeal to my inner 12 year old.

I also watched the show and one factor they did not take into account
was the speed of an airliner at altitude. Also, what would happen to
the forces on the damnaged airframe during the descent/emergancy
landing? As in most tests, this was a controlled experiment. I'm sure
if they placed the shaped charge closer to the wing root, more
damnaged would occure.

Still a good show, I especially like the part where they used a 22
bullet for a fuse replacement.

"Bob Gardner" writes:

The speed of the airplane at altitude has nothing to do with it. The
pressure differential between the cabin and the great outdoors is the only
factor...airspeed does not exert any pressure on the sides of the fuselage.

In the case of a bullet hole, it's probably not significant (although
I'd think the exit hole would would be somewhat ragged, and would
stick out into the airstream, so even that might). In the more
extreme cases, where they used shaped charges to blow out many square
feet of fuselage, I'd have thought the airstream would be a *very*
important factor in what happened next.
--
David Dyer-Bennet, , http://www.dd-b.net/dd-b/
RKBA: http://noguns-nomoney.com http://www.dd-b.net/carry/
Photos: dd-b.lighthunters.net Snapshots: www.dd-b.net/dd-b/SnapshotAlbum/
Dragaera/Steven Brust: http://dragaera.info/

Bob Gardner wrote:
The speed of the airplane at altitude has nothing to do with it. The
pressure differential between the cabin and the great outdoors is the only
factor...airspeed does not exert any pressure on the sides of the fuselage.

Bob Gardner



Well, yes and no.

It depends on the shape of the hole and its placement relative to the
geometry of the fuselage (that is: relative to the apparent air flow).
With speed, the hole may assist adding pressure (as does a
forward-pointing pitot tube) or it may assist depressuring, due to
Bernoulli effect, (as demonstrated by a household-plumbing vent-stack in
a strong wind).