Boeing 747 survives simulation bomb blast

[Flying Wild]

BBC News - Boeing 747 survives simulation bomb blast (http://news.bbc.co.uk/1/hi/world/8548021.stm)


A test explosion on a Boeing 747 suggests that a US Christmas Day flight would have landed safely even if a bomb on board was detonated successfully.
The test plane's fuselage did not break in the controlled blast, which used the same amount of explosive allegedly carried by Umar Farouk Abdulmutallab.
Mr Abdulmutallab, 23, has denied attempting to murder 289 people by trying to blow up a flight to Detroit with a device hidden in his underwear.
The experiment was carried out by UN explosives expert Dr John Wyatt and analysed by air accident investigator Captain J Joseph.


It looks to me from the video as if the aircraft was not pressurised. Surely that would have an impact on how effective the bomb would have been?

[LAS1997]

Also, its detonated along the strongest part of the aircraft, the wing root and not further ahead as in the case of the Pan Am 747 in 1988.

I note it looks like an old Cathay Pacific 747-200 freighter that came to the UK for breaking up. I guess the freighters have strengthened floors, etc, so stronger than normal passenger aircraft?

[Checkboard]

Mythbusters pressurised an airframe, then fired various guns through windows and the like, before finally blowing it up. Search for that. :ok:

[AnthonyGA]

Mythbusters pressurised an airframe, then fired various guns through windows and the like, before finally blowing it up.

Yes, but they did that on the ground, where the ratio of inside to outside pressure was much smaller than it would be at altitude, and the outside air density was much higher, so their tests are not necessarily representative of what would happen at high altitudes.

[Peter Fanelli]

What a worthless test, about what I'd expect from the United Nations.

[Checkboard]

Yes, but they did that on the ground, where the ratio of inside to outside pressure was much smaller than it would be at altitude, and the outside air density was much higher, so their tests are not necessarily representative of what would happen at high altitudes.

As I recall, they set up the best differential they could get - which was pretty close to the operational figure. The reactions of the fuselage in the initial second or so would have been under the same impetus, and thus almost identical. I thought it was a pretty good test, short of automating and airliner, and flying it to altitude! :)

[vs69]

Watch the 'If it's not Boeing I'm not going' brigade fill this thread up. Yaaaaaawwwwwn.

[fire wall]

ex B-HVY ?
How dare they treat her with such disrespect !

[Linedog]

It won't cause much damage as all the doors are open. Instant escape route for the pressure build up. :ugh:

[David Horn]

Possible they did seal off that part of the fuselage since I didn't see any explosive gases escaping from the doors. However, agree that unpressurised it's not a representative test.

[Davidsoffice]

Looks to me as though the explosion also detonated the cockpit crew escape system!

[7AC]

I'm glad to see both wearing their yellow jackets, very important for aviation safety!

[Mike-Bracknell]

What a worthless test, about what I'd expect from the United Nations.

I think you're missing the point. This is obviously aimed at the average wannabe terrorist who might think again about blowing their nob off in the name of allah if it's not going to take down the aircraft, and hasn't got the relevant knowledge of relative atmospheric pressure, etc.

[SMOC]

ex B-HVY ?
How dare they treat her with such disrespect !

Nup it was HIH, HVY is long gone, RIP

Also what happens when they're pressurised

YouTube - 747 test (http://www.youtube.com/watch?v=d515OjToRxY&feature=related)

[AeroMad]

Very unreliable test.
As said by other posters, the cabin was not pressurised, and the doors were open... thus allowing excess pressure from the explosion to escape from the aircraft.
And regards the Pan Am incident, the initial explosion wasn't the sole cause to the aircraft disintegrating, the shockwaves travelling within the pressurised cabin also played a part...

Regards
AeroMad

[Tester_76]

And now Mr Terrorist knows to bring more bang with him for the next attempt

[lurkio]

Oh well, al least it gives his defence team enough to work on to get him off. What a waste of time, different type, nil differential, sea level etc. etc. At least Mythbusters would have blown everything up at the end.
A couple of new rivets and it'll be flying again next week!

[VS1711]

I shouldn't worry Tester - I'm told there's a limit to the amount of explosive power you can hide in your underpants. :}

[169west]

With nowadays modeling and simulation technology it is possible to reproduce the consequence of an IED explosion at 40 kft on a pressurize 747 just by standing in front of a computer. So it is not believable they didn’t evaluate the variables involved in such a scenario.
Or maybe they are just trying to communicate a positive message to everyone who still thinks flying on an airplane is more dangerous then driving a car. Good for the economy and good for airline business!

Here same videos on the Philippine Airline 434 (http://en.wikipedia.org/wiki/Flight_434)
Air crash investigation part 1 (http://www.youtube.com/watch?v=zXMzdncZ_wo)
Air crash investigation part 2 (http://www.youtube.com/watch?v=kyA8decJ55g&feature=related)
Air crash investigation part 3 (http://www.youtube.com/watch?v=jdG5qON7m-o&feature=related)
Air crash investigation part 4 (http://www.youtube.com/watch?v=YmAE_f2bh-I&feature=related)
Air crash investigation part 5 (http://www.youtube.com/watch?v=5tYqtM6jYqk&feature=related)

[Blythy]

that doesn't look like glass in the windows, nevermind that whatever material was filling the window holes, seemed to get "popped out"

Also, doing a pressurised test on the ground is dodgy as well, as to get the right pressure ratio, you'd have to pump the cabin full of air, and that'd add more oxygen changing the power of the explosives.

[Basil]

It's a freighter; the windows are blanked off - or at least they were last time I flew it :)
p.s. Actually a pax conversion.

[protectthehornet]

boys and girls...

so, there you are flying along and your FA calls up and says there is a bomb on board...some of us old farts remember that

in the film "Airport" they started a descent to reduce the differential and some of us have long ago decided to de pressurize the plane upon warning of a bomb ( and of course we would use caution if the bomb was a barometric bomb, triggered by higher altitude)

I think it is a fair test, but both pressurized and unpressurized test would be of interest.

also, do you guys know what : LRBL means? don't write it here...just yes or no

[Tester_76]

I shouldn't worry Tester - I'm told there's a limit to the amount of explosive power you can hide in your underpants. http://images.ibsrv.net/ibsrv/res/src:www.pprune.org/get/images/smilies/badteeth.gif


Next guy just has to have bigger balls :cool:

[AeroMad]

also, do you guys know what : LRBL means? don't write it here...just yes or noSimple answer, yes...

[Spunky Monkey]

Long Range Bomb Loader?

Start the timer in Amsterdam and wait till Detroit...Its the term for Abdullah's Handler and Mentor!

[TyroPicard]

Blythy
and that'd add more oxygen changing the power of the explosives.
Surely explosives already contain the oxygen they require?

[lomapaseo]

Video stunt test for publication are for entertainment.

It is not in the good guy's interest to illustrate weakness or strength against the bad guys.

Face it

The bad guys win everytime we publish the desired results of their attempts to affect our global thinking.

[infrequentflyer789]

also, do you guys know what : LRBL means? don't write it here...just yes or no

I thought where it is, not what it means, was the "secret"... [yes]

Also it may be that they did this test with the dummy in the seat in which this passenger sat. That would also be a perfectly valid test (depending on what you are trying to determine).

A smart bomber might have sat somewhere else, but these guys don't need smart bombers, a few dumb ones and the TSA et al. will cause the rest of the terror.

First the shoes, then the drinks, then the underpants, and we all know where the next one will be (once the hassle with the body scanners has all died down). Human rights and religious discrimination rulings will ensure that the faithful are exempted (the fatwa has already gone out against the body scanners and two have tested the rules at MAN, watch the lawsuits follow). The rest of us get to pass the vaseline or not fly. Heads they win, tails we lose. No need to actually suceed in blowing anything up.

[er340790]

Tester 76 makes a valid point. Surprised the presenter didn't go on to say just how much explosive would be required.


There's a bomb on board.

A b...????

No, not a b... A bomb!

:} :} :}

[Dimitris]

also, do you guys know what : LRBL means? don't write it here...just yes or no

I do now.. just googled it...

[Blythy]

Surely explosives already contain the oxygen they require?

I wasn't sure about that bit :p However, it would affect the materials surrounding the explosive. Expecially velco (see Apollo 1), which is lethally flammable in oxygen rich environments (I know it wouldn't affect the explosive power, but it would exagerrate flame effects.

[max nightstop]

LRBL - Isn't that the French abbreviation for the Royal Belgian Wrestling Federation?

It was a crap test. Tricky to find a volunteer to fly an accurate one and who is going to lend you the plane? Perhaps we should set one up and ask the two guys who ran the test if they want to come along for the ride.

[dabchick]

This was B-HVY. Has been at Kemble for a long time. Has been in 'knackers corner' since middle of February. Passed by on Wednesday and has been totally reduced to produce.

[Taildragger67]

Air pressure differentials aside, would the fact that this test was carried out using the same amount of material as was carried on an A330, but on a 747, also question its validity from the aspect that a 747 would have a greater internal volume in which to accommodate the explosion and resulting pressure waves?

[Basil]

dabchick,
This was B-HVY
Are you sure?
IIRC, since HVY was built as a freighter and was not converted from a passenger aircraft, she didn't have blanked windows.

[CAT1 REVERSION]

Guys,

I think a few of you are missing the point here!

The test from what I saw last night on BBC2's 'How Safe Are Our Skies' was to replecate the attempted bomb attack by Umar Farouk Abdulmutallab on Christmas Day 2009, and what would have happened should he have been succesful.

The attack was designed by the terrorists to detonate at low altitude, approx 10,000'. Therfore the Px diff would have been minimal - hence the test being conducted on an un-pressurised airframe. Not ideal, what with pressure waves confined to a sealed slightly pressurised hull would be more damaging than a hull open to atmosphere, nethertheless, the test served a purpose.

The test was also conducted in a stripped back airframe, where all internal panels/Insulation/Sound prrofing etc had been stripped away, and the skin still contained the blast.

I don't think you can rubbish this test, not ideal, but did show (even in an aging hull) that the quantities of explosives this idiot used were probably not enough to down the aircraft. Joe public I'm sure would take a lot from this test in reassuring just how well made most airfcraft are.

You can watch the program here on BBC iplayer:

BBC iPlayer - How Safe Are Our Skies? Detroit Flight 253 (http://www.bbc.co.uk/iplayer/episode/b00r902b/How_Safe_Are_Our_Skies_Detroit_Flight_253/)

Good job by the pax and crew.

[SimJock]

I wonder how a plastic 'dreamliner' would have coped under similar conditions ?

[lomapaseo]

don't think you can rubbish this test, not ideal, but did show (even in an aging hull) that the quantities of explosives this idiot used were probably not enough to down the aircraft. Joe public I'm sure would take a lot from this test in reassuring just how well made most airfcraft are.


OK I'm reassured now let's stop this sham about personal body scans and minimal risk from terrorist mules.

[Storminnorm]

Anyone know where we can get hold of a Dreamliner
to check it out?

[CAT1 REVERSION]

lomapaseo,

OK I'm reassured now let's stop this sham about personal body scans and minimal risk from terrorist mules.

The point isn't the lack of security but the test of a 747 hull versus explosives. Security will always be needed as will the advance in technology to detect such devices, but what the test did show was how strong the fuesalage actually is - hopefully detering in some way future (similar) attacks. If the results of this test increase public confidence in flying that can only be a good thing for the future of aviation!

[lomapaseo]

The point isn't the lack of security but the test of a 747 hull versus explosives. Security will always be needed as will the advance in technology to detect such devices, but what the test did show was how strong the fuesalage actually is - hopefully detering in some way future (similar) attacks. If the results of this test increase public confidence in flying that can only be a good thing for the future of aviation!

Great theory but it won't work.

We are dealing with general ignorance at the public's level. Blowing things up just reinforces their fear that they are at risk from even their seat mates. We certainly aren't going to educate the bomb makers who know how to capture the publics attention with the tiniest of bombs even if all they do is blow there own nuts off in the middle of the inflight meal.

Those in aviation already know how tolerant the aircraft is or isn't so we didn't need the test. This is all PR and the bad guys will always win at this with their next trick even if it's all smoke.

[CAT1 REVERSION]

I agree, there will always be a threat to aviation with it being a high profile industry. Damage limitation is the best we can hope for, but the loss of public confidence will damage the aviation Industry far worse than any 'underpant bomber'.

If the program and test for all it's worth did restore a modicom of confidence to those fearful of such atrocities - that has to be good...no?

[lomapaseo]

If the program and test for all it's worth did restore a modicom of confidence to those fearful of such atrocities - that has to be good...no?

Yes......... how do we confirm this? by less intrusive searches?

[D O Guerrero]

Cabin Diff Pressure at 10,000ft - about 4psi? I'm not an engineer, but surely this would have a significant effect on the effectiveness of the device?

[rottenray]

Anthony writes:

Yes, but they did that on the ground, where the ratio of inside to outside pressure was much smaller than it would be at altitude, and the outside air density was much higher, so their tests are not necessarily representative of what would happen at high altitudes.Nope. Air is air. Density is density. A 10 psi difference is the same at sea level as it is at fl800. Air doesn't get "thicker" or "thinner" based on altitude, only the pressure changes. Mythbusters pressurized to the correct PSI to represent cruise altitude, so their "bullet" test was accurate.


Watch the 'If it's not Boeing I'm not going' brigade fill this thread up. Yaaaaaawwwwwn.Had the UK team even sealed the vessel, that 747 would have popped something - a widow, or a lap joint.

But, if you insist we talk about this, I'll take a 737 minus the crown over over first class any day.



Possible they did seal off that part of the fuselage since I didn't see any explosive gases escaping from the doors. However, agree that unpressurised it's not a representative test.The test team explained that they DID NOT seal the fuse for this demonstration, and explained it away in terms of moving air pressure.

They're completely wrong, of course. Because the fuse was unsealed, there was no effect from the sheer increase in pressure caused by the explosion.



I think you're missing the point. This is obviously aimed at the average wannabe terrorist who might think again about blowing their nob off in the name of allah if it's not going to take down the aircraft, and hasn't got the relevant knowledge of relative atmospheric pressure, etc.Not to be argumentative, but this little piece of journalism was aimed at the flying public. I suspect they used a big old hunk of thick-skinned 747 for the purpose of being able to film the shock waves running down its skin, counting on that it wouldn't pop a seam.

The wannabe terrorists don't really think about their knobs much, if they did they would certainly be asking more (and more pointed) questions about the 72 virgins awaiting them in the afterworld.

Questions like "what do they look like? why are they still virgins? how come there are 72 of them just for me, are they like, common, or what?"


And now Mr Terrorist knows to bring more bang with him for the next attemptThe guys' bosses gave him just enough to burn half his johnson off. If they had been serious, they would have given him enough to get the job done, but one suspects that's not what they wanted to do.

Why anyone thinks this was an inept attempt at blowing up a flight is beyond me. They know exactly how to do it. They don't bother to go all the way, because setting some poor sap up on a mission which will just burn half his johnson off gets the same job done.

Terror. Sheer, media-fueled terror. Knee-jerk reactions. Comments in forums... Oh - did I say that?



The test was also conducted in a stripped back airframe, where all internal panels/Insulation/Sound prrofing etc had been stripped away, and the skin still contained the blast.No, not at all. The ends of the "tube" were open, so the pressure wave could roll on out. Had they detonated the same amount of stuff in a sealed 747, the internal pressure - by my rough calcs - would have gone up to something like 72 psi.

That would have produced something more than the cute little skin wiggles we saw in the long view when the "test" explosive was detonated.



This is all PR and the bad guys will always win at this with their next trick even if it's all smoke.:ok:


Best comment so far, besides this one.

Let's just be glad we had some pax and some CC who were quick to respond.

The FD folks did what they were supposed to do, which is keep flying the plane.

The US FAM were apparently doing what they're paid to do, which is ride and monitor "some" flight or another, but it didn't happen to be this one.

And the terrorists did what they do best - they scared the sh*t out of us again, by simply de-nutting one of their own and giving him up for bait. The net result is that your grandmother might now become a pornstar of the "grainy, nightshot" type the next time she puts her tired old pu...

Puts her tired old self on a flight to come see you.


Everything else is window dressing.

RR

[bcgallacher]

I am puzzled as to what this expensive excercise was supposed to prove- it strikes me as totally irrelevant to the real world - B747s do not fly around unpressurised with the doors removed.