Mythbusters...SBS Monday night 17 March
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Re original question
Would depend on the Non pilot piloting. Big difference say between me (aviation enthusiast since knee high to a grasshopper and knows about lift, thrust, ailerons, rudder, elevator control etc etc) and someone 'off the street' with zero aviation knowledge.
I'd give it a go (I'd insist if there were no pilots onboard!LOL!) preferably with a chase plane alongside and my brother or one of my mates talking me through it all depending on what type I was "flying"!
I find watching 'Mythbusters' torturous; big on hype, light on tech details , way too drawn out and too many adds.
Cheers
Octane
I'd give it a go (I'd insist if there were no pilots onboard!LOL!) preferably with a chase plane alongside and my brother or one of my mates talking me through it all depending on what type I was "flying"!
I find watching 'Mythbusters' torturous; big on hype, light on tech details , way too drawn out and too many adds.
Cheers
Octane
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F/A 18 - it's the diff pressure that matters, not the actual outside pressure.
Provided they got the diff right it wouldn't matter whether they were at sea level or 50,000'.
Provided they got the diff right it wouldn't matter whether they were at sea level or 50,000'.
If they pressurised the aircraft to a typical 8000', but it remained on the ground at the 3000' high Mojave Airport, then there was never going to be enough of a pressure differential to get an explosive decompression.
If they aimed for the correct pressure differential, in order to replicate the air pressure differential for an airliner flying at, say, FL250, they would have had to pump the jet up many more times than the normal amount, someting I doubt the structure of a new aircraft, let alone a hulk with their dodgy brothers patches would have been able to take.
Make sense?
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sheezus wept Fox Alpha....I hope you don't actually fly F-18's with that sort of misunderstanding about something as basic as differential pressure, please tell me you're just a high school kid who wants to one day fly a jet??
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FA18,
to get the correct differential pressure, they sealed the fuselage and then pressurised it using a ground air source. They then measured the pressure both inside and out, and from that, had a readout of the differential.
to get the correct differential pressure, they sealed the fuselage and then pressurised it using a ground air source. They then measured the pressure both inside and out, and from that, had a readout of the differential.
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Ever heard of downloading eps off the net? Seen this one ages ago. Will not spoil it.
The best one is a few more weeks "the airplane on a conveyor belt":
"A plane is standing on a runway that can move (some sort of band conveyer). The plane moves in one direction, while the conveyer moves in the opposite direction. This conveyer has a control system that tracks the plane speed and tunes the speed of the conveyer to be exactly the same (but in the opposite direction). Can the plane take off?"
So if the belt is matching the take off speed (in the opposite direction to travel) of a lightie, will it take off?
The best one is a few more weeks "the airplane on a conveyor belt":
"A plane is standing on a runway that can move (some sort of band conveyer). The plane moves in one direction, while the conveyer moves in the opposite direction. This conveyer has a control system that tracks the plane speed and tunes the speed of the conveyer to be exactly the same (but in the opposite direction). Can the plane take off?"
So if the belt is matching the take off speed (in the opposite direction to travel) of a lightie, will it take off?
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Originally Posted by Dave Incognito
to get the correct differential pressure, they sealed the fuselage and then pressurised it using a ground air source. They then measured the pressure both inside and out, and from that, had a readout of the differential.
But atmospheric pressure at an airliner's cruise altitude of, say, FL300 is about 1/3 that of 3000', so surely in order to obtain a comparative pressure differential, they would have had to pressurise the aircraft fuselage to a level three times that of the normal pressurisation level - I doubt an aircraft fuselage could withstand that.
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Well, I for one will be watching, even if only to try to spot the mistakes. I find ‘Mythbusters’ entertaining and generally fairly well researched. The pressurized bullet hole episode was within the parameters of possibility and these guys had gone to a fair bit of trouble to approximate the conditions as much is as possible. If you can get the right advice at Mojave regarding things aeronautical as there are a few establishments on site with a fair amount of aerospace expertise.
I was working at Mojave a few years ago when the spaceship one made its first ( unpowered) flight very early one morning, which I have to say is the best part of the day in that region. It was almost surreal to be in the que at the holding point along with a SAAB Draken, an MB326 and the Rutan Mother ship. Some of those Rutan things are a bit surreal themselves for that matter. Did you know that ‘Waterworld’ was filmed at Mojave airport, a movie about a sea covered planet filmed in the middle of one of the driest places known to man. I think that the prop ship they built is still there amongst the derelict airliner hulls target drones and C133’s. A couple of guys towed a very tatty F100 of the lot and into a hangar one day and about three days later I watched as it blasted off somewhere without even a cautious lap around the block on climb. The guys from just down the road used to come up in their F117’s and do some very low beat ups, er sorry, missed approaches with delayed climb establishment. Er, seem to be straying somewhat from the topic here.
Regarding the pilot incapacitation thing there is a great novel by the aerobatic pilot and author Brian Lecomber about a woman who manages to land a Cherokee after her hubby karks it at the wheel. The book is called Talk Down and along with Lecombers other two books is a great read. If you like accurate aviation novels this guy is very very good.
Anyhow, Mythbusters is a fun show, and remember, this is light entertainment for the great unwashed, not real rocket science after all. Having spent uncountable nights in hotels and motels from here to the Mariah country inn, an episode of MB on the Discovery channel is way ahead of most other televisual offerings, especially when there are about 37 other channels devoted to soaps and 57 channels dedicated to every kind of the most excruciatingly boring sporting events. Some MB and a modest serving of that reality show featuring a gorilla with a walrus mustache shouting at his offspring and kicking doors off their hinges in a motorcycle shop is almost enough to keep me out of the piano bar for a couple of hours. Hmmmm, maybe not.
HD
I was working at Mojave a few years ago when the spaceship one made its first ( unpowered) flight very early one morning, which I have to say is the best part of the day in that region. It was almost surreal to be in the que at the holding point along with a SAAB Draken, an MB326 and the Rutan Mother ship. Some of those Rutan things are a bit surreal themselves for that matter. Did you know that ‘Waterworld’ was filmed at Mojave airport, a movie about a sea covered planet filmed in the middle of one of the driest places known to man. I think that the prop ship they built is still there amongst the derelict airliner hulls target drones and C133’s. A couple of guys towed a very tatty F100 of the lot and into a hangar one day and about three days later I watched as it blasted off somewhere without even a cautious lap around the block on climb. The guys from just down the road used to come up in their F117’s and do some very low beat ups, er sorry, missed approaches with delayed climb establishment. Er, seem to be straying somewhat from the topic here.
Regarding the pilot incapacitation thing there is a great novel by the aerobatic pilot and author Brian Lecomber about a woman who manages to land a Cherokee after her hubby karks it at the wheel. The book is called Talk Down and along with Lecombers other two books is a great read. If you like accurate aviation novels this guy is very very good.
Anyhow, Mythbusters is a fun show, and remember, this is light entertainment for the great unwashed, not real rocket science after all. Having spent uncountable nights in hotels and motels from here to the Mariah country inn, an episode of MB on the Discovery channel is way ahead of most other televisual offerings, especially when there are about 37 other channels devoted to soaps and 57 channels dedicated to every kind of the most excruciatingly boring sporting events. Some MB and a modest serving of that reality show featuring a gorilla with a walrus mustache shouting at his offspring and kicking doors off their hinges in a motorcycle shop is almost enough to keep me out of the piano bar for a couple of hours. Hmmmm, maybe not.
HD
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I doubt an aircraft fuselage could withstand that.
AustralianMade
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Mr. FA18,
Surely you are having a little fun with us...
A pressure vessel only has to withstand the differential pressure it is exposed to. If the vessel is designed to withstand 7psi and the atmospheric pressure around it is 1000psi then the bloody thing can be pressurised safely to 1007psi!
Translate this to our aircraft on the ground and it is clear to most that you can pressurise an aircraft hull to its rated pressure whether it is on the ground or at FL390. The pressure differential is still the same.
Logical thought provides for the fact that airliners must be pressure tested on the ground as part of their maintenance, so it must be possible.
I doubt an aircraft fuselage could withstand that.
A pressure vessel only has to withstand the differential pressure it is exposed to. If the vessel is designed to withstand 7psi and the atmospheric pressure around it is 1000psi then the bloody thing can be pressurised safely to 1007psi!
Translate this to our aircraft on the ground and it is clear to most that you can pressurise an aircraft hull to its rated pressure whether it is on the ground or at FL390. The pressure differential is still the same.
Logical thought provides for the fact that airliners must be pressure tested on the ground as part of their maintenance, so it must be possible.
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I'll never forget the show they did to try to prove/disprove the explosive decompression myth.
They used a hulk at the boneyard at Mojave Airport, sealed and pressurised the fuselage, and and then shot a bullet into it to see if it would explosively decompress. Of course it didn't, so they declared the myth busted.
What they failed to take into account was the outside pressure of the aircraft was equivalent to about 3000' ASL, the height of Mojave Airport, not >20K' where an explosive decompression would occur!
your wrong there foxtrotalpha,they used a px gauge to measure cabin px to outside px,the differential was about 9 psi,which is about right at cruise altitude
They used a hulk at the boneyard at Mojave Airport, sealed and pressurised the fuselage, and and then shot a bullet into it to see if it would explosively decompress. Of course it didn't, so they declared the myth busted.
What they failed to take into account was the outside pressure of the aircraft was equivalent to about 3000' ASL, the height of Mojave Airport, not >20K' where an explosive decompression would occur!
your wrong there foxtrotalpha,they used a px gauge to measure cabin px to outside px,the differential was about 9 psi,which is about right at cruise altitude
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I would like to include those that watch this tosh in my original statement
Personally,I find Mythbusters far more interesting than most the other rubbish we are subjected to on free to air.
AustralianMade
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Serious question for QF.M.O. or any tech types.
QF.M.O.,
Why would this matter if they got the pressure differential correct?
Someone above has quoted 9psi, is that enough to do it?
Also, I seem to recall that they then had a bit of fun with the pressurised hull and some explosives!
What they failed to take into account was the outside pressure of the aircraft was equivalent to about 3000' ASL, the height of Mojave Airport, not >20K' where an explosive decompression would occur!
Someone above has quoted 9psi, is that enough to do it?Also, I seem to recall that they then had a bit of fun with the pressurised hull and some explosives!