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lpetrich
Skeptic Friend
USA
74 Posts |
 Posted - 09/18/2001 : 23:17:03
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I just thought of an interesting one.
The silent-alarm approach was mentioned by others, but what it could do is make possible the following:
The airliner's autopilot puts it on some suitable course (straight line, big circle), but it can be overridden by commands from the ground. Someone on the ground can then take over the aircraft and fly it to some suitable spot and try to land it somewhere.
This may even include telling the airliner to dump its fuel, turning it into a giant glider.
Control may be given back to the plane's pilots if the people on the ground decide it's OK.
Helpful for this would be video cameras in the nose, the cockpit, and in the front of the cabin.
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bestonnet_00
Skeptic Friend
Australia
358 Posts |
Posted - 09/19/2001 : 01:31:23 [Permalink]
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OK, so if I were a terrorist I would just figure out how the signals to take over the aircraft work. Then all I need to do is send them to the aircraft and fly it into another building remotely.
That is even worse as it will allow the terrorists to be able to take over more aircraft and with no need to get weapons onto the airliners.
If the pilot has to give control to the ground then I would just have to get someone onto the jetliner. They don't have to know how to fly it. Just do something to get the pilot to give control to the ground.
Radioactive GM Crops.
Slightly above background.
Safe to eat.
But no activist would dare rip it out.
As they think it gives them cancer. |
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lpetrich
Skeptic Friend
USA
74 Posts |
Posted - 09/19/2001 : 01:43:58 [Permalink]
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But there is a simple solution:
Encryption.
The encryption keys would be uploaded to the airplane on the ground, and the system would be verified as part of the takeoff preparations.
Something like that is used at the Kennedy Space Center for many of its rockets; they have explosive charges which are to be detonated by remote control if they stray too far off-course. The communication involves sending a self-destruct password, as it were; the exact password is a closely-guarded secret.
That particular solution is too drastic for airliners, but the principle still applies.
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Greg
Skeptic Friend
USA
281 Posts |
Posted - 09/19/2001 : 06:27:45 [Permalink]
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I am not a pilot but I thought that large airliners, if the engines shut down (no fuel) would drop from the sky like a rock rather than glide.
Greg.
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Tokyodreamer
SFN Regular
USA
1447 Posts |
Posted - 09/19/2001 : 08:26:08 [Permalink]
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This would only work if we adopted a policy of not caring whether or not the hijackers start slitting passengers' throats until we gave them command of the plane.
And I believe Greg is right, I don't think jumbo jets are very good at gliding with zero forward thrust.
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Hope springs eternal but there's no conviction
Actions mistaken for lip service paid
All this concern is the true contradiction
The world is insane... |
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@tomic
Administrator
USA
4607 Posts |
Posted - 09/19/2001 : 08:34:45 [Permalink]
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I heard a story on the news recenty about an Airbus plane that glided a long, long way.
@tomic
Gravity, not just a good idea...it's the law! |
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Tokyodreamer
SFN Regular
USA
1447 Posts |
Posted - 09/19/2001 : 09:29:23 [Permalink]
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quote:
I heard a story on the news recenty about an Airbus plane that glided a long, long way.
Oops, you're right, and I forgot that someone here recently explained this stuff about glide ratios.
A 747 can glide about 15 miles for every mile of altitude (or 15:1 of whatever units you want to use).
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Hope springs eternal but there's no conviction
Actions mistaken for lip service paid
All this concern is the true contradiction
The world is insane... |
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Trish
SFN Addict
USA
2102 Posts |
Posted - 09/19/2001 : 09:43:31 [Permalink]
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Ok, Greg: The glide-slope ratio (remember from math however many years ago that was for anyone) so many feet of forward movement for feet of downward movement. Most of these large aircraft have a glide-slope ratio of 17:1 or 16:1. Which is quite good.
One way to force an aircraft into the ground is to put the flaps in the full up position (trailing edge of the wing) and have the slats (leading edge of the wing) in and rotate the alerons (horizontal on the tail) so the leading edge is up. This will quickly force the aircraft down by the air flow over the wings. Flaps, slats and alerons can be used to maximum effectiveness to keep an aircraft in the air. Bernouli's principle.
Having worked on ACLS (Aircraft Carrier Landing Systems) and ILS (Inertial Landing Systems) these control systems are from about 30 years ago and quite accurate. So accurate in fact, that the Navy/Marine Corps had to build in a fudge factor to keep tail hooks from wearing gouges in the landing deck of the carrier when catching the #3 wire.
Bestonnet: you're assuming that they are going to use unclassified transmissions. They aren't that silly (at least I don't think). Having dealt with encrypted codes etc, it is possible to have a carrier code encrypted into the system. This code would have to change daily and would take approximately 30-40 seconds to dump and change each day or each flight.
Where you run into logistical problems is the number of flights that changing these codes are required for. Which simply means that the encryption code must be an extremely long alpha-numeric sequence. This in itself is not a bad thing because it would take longer to crack the sequence. However, they can scramble the information between the ground and the aircraft and a program or piece of equipment would then translate the scramble. Generally, in the military this type of equipment is designed to disintegrate easily. This prevents recovery of classified material from crash sites.
In essense we could make it very difficult for hi-jackers to take over our civilian aircraft. However, they've been discussing just this on the news recently. The cost per aircraft less than 10 years old $300,000 US.
Sometimes the simplest solution is the best. Provide the pilots with separate access and have them confined away from the passengers.
He's YOUR god, they're YOUR rules, YOU burn in hell! |
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Kaptain K
New Member
USA
45 Posts |
Posted - 09/19/2001 : 10:49:48 [Permalink]
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Trish,
Let me second your suggestion that the flight crew have their own entrance. Give them their own restroom and food prep area. Put a reinforced (steel & kevlar) bulkhead between the flightdeck and the passenger space with NO access between the two.
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Greg
Skeptic Friend
USA
281 Posts |
Posted - 09/19/2001 : 15:20:50 [Permalink]
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Trish, Thanks for the lesson. I guess that I made an assumption based on the airliners mass and non glider-like shape.
I don't think that confining the crew would stop all types of air terrorism - only the type that occoured last week (very rare). It certainly wouldn't stop the 'normal' hijacker who wants to take over an aircraft for some demand (not so rare). All one needs to do is threaten to harm passengers.
The best policy here is to prevent would-be hijackers from boarding. The major focus should be placed on heightened airport security no matter the cost. The Gore committee study (1997) outlined these types of improvements but the airline industry successfully lobbied to have it killed in conference.
Greg.
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@tomic
Administrator
USA
4607 Posts |
Posted - 09/19/2001 : 20:13:15 [Permalink]
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quote:
The Gore committee study (1997) outlined these types of improvements but the airline industry successfully lobbied to have it killed in conference.
Oh yeah, that same airline industry our tax dollars now have to rescue because of their own cheapness. Not only that but they want protection from lawsuits. Must be sweet to own politicians like that. I hope I get one for Christmas.
@tomic
Gravity, not just a good idea...it's the law! |
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Trish
SFN Addict
USA
2102 Posts |
Posted - 09/20/2001 : 08:34:20 [Permalink]
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Greg: the aircrew were following the rules for the normal type of terrorist that values his life. This is game theory, everyone has something to benefit by cooperation.
Unfortunately, the massive number of people in the US really prevents the US from tracking potential/would be terrorists. Besides, the monitoring of people because of nationality, religion or any other classification is really counter to our rights and freedoms as Americans. This is the price we pay for our freedom. It has wreaked a terrible toll, do we give up our rights as citizens for safety? Or do we keep our rights and assume the risks imposed by our choice for our freedoms?
This is the question that has been kicked around alot. One CIA agent that was being interviewed answered the question of giving up rights as Americans with an unequivocable NO! His reasoning, then the terrorists win by erroding our freedoms. I must say that I am in complete agreement with his answer and reasoning. I would rather choose my freedom to my safety - consider it my personal responsibility anyway.
Off the rant subject.
As for airline security, well, we've always known it was less than exlempary. Figure that a hamburger flipper makes more than a security guard at the airport. Well, you see the caliber of personnel your going to wind up with.
He's YOUR god, they're YOUR rules, YOU burn in hell! |
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bestonnet_00
Skeptic Friend
Australia
358 Posts |
Posted - 09/22/2001 : 00:10:40 [Permalink]
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On many intercontinental aircraft there is a sleeping area underneath the floor (wide body only) for the Pilots to sleep while other Pilots take over. To get to it the pilots have to walk through the passenger area.
What could be done about that?
Radioactive GM Crops.
Slightly above background.
Safe to eat.
But no activist would dare rip it out.
As they think it gives them cancer. |
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Trish
SFN Addict
USA
2102 Posts |
Posted - 09/22/2001 : 08:08:28 [Permalink]
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Aircraft are designed as a tube first (the outer body). Simply enlarge the pilots area - insert something similar to train sleeping compartments at the back of the cockpit. Granted it's expensive - but it does prevent the type of terrorist attack that happened on the 11th. It shouldn't be too difficult to retrofit most aircraft to separate access for the pilots.
He's YOUR god, they're YOUR rules, YOU burn in hell! |
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