At 06:05 PM 9/12/2001, you wrote:
Quite more interesting is why nobody noticed that 4 airliners where hijacked almost the same time.
Not surprising. Aircraft are "flight followed" by a series of control centers across the nation, each responsible for a given chunk of airspace. Something happening in an area controlled by Center "A", for example, wouldn't be passed on to Center "B" (which has it's own problems to work) unless it impacted Center "B". Furthermore, unless someone TELLS Center they're being hijacked, there's no way for a controller - looking at
a blip - to know what's up. And any controller can tell you that pilots do
Somehow the people who did this managed to turn off the transponders on these planes. Normally a plane flying in controlled airspace squawks a unique id and altitude which is decoded by their radar and associated with each blip. Sometimes low cost homebuilts/ultralights fly with no transponder, but Boeings <sarcasm>usually</sarcasm> do. If you set a transponder to 7500, it means you're being hijacked. BTW if you see your friend Jack at the airport, be sure to say, "What's up, Jack!" instead of "Hi Jack!" So how do you deal with this? Blowing up a whole country? I wonder if the US should adopt a 'fire w/ fire' approach and invest in intelligence, covert ops and assassinations. It would seem that it is open season on terrorism by every democratic nation, I expect to see very conspicuous Samuel Jackson style ass whoopins on whiny extremist groups to satiate America's anger. Terrorize the terrorists. Oh yeah, obviously Echelon should probably have MacOS loaded on it. -b
I despise posting off-topic, but I want to say two things... 1. If a transponder is turned off, it doesn't mean that you don't show up on radar--a blip appears on the radar screen as long as you're high enough to be detected. If however you fly low enough, you can fly below the radar's detection capability. I don't offhand recall what height that is--it's been years since I was active as a pilot and prospective Air Traffic Controller. 2. What's the point of having transponder codes for hijacking if they're so well published everyone is aware of them? The purpose of the codes was so that the pilot could communicate this information without the hijacker becoming aware of what was happening. I have always REALLY DISLIKED the now common practice of advertising this information. You're taking away one of the pilot's best tools... -- Leigh Anne
-----Original Message----- From: owner-nanog@merit.edu [mailto:owner-nanog@merit.edu]On Behalf Of Hire, Ejay Sent: Thursday, September 13, 2001 2:35 PM To: 'Borger, Ben'; 'nanog@merit.edu' Subject: RE: Analysis from a JHU CS Prof
The transponders, like most avionics, has a handy-dandy off switch.
-----Original Message----- From: owner-nanog@merit.edu [mailto:owner-nanog@merit.edu]On Behalf Of Borger, Ben Sent: Thursday, September 13, 2001 2:32 PM To: 'nanog@merit.edu' Subject: FW: Analysis from a JHU CS Prof
At 06:05 PM 9/12/2001, you wrote:
Quite more interesting is why nobody noticed that 4 airliners where hijacked almost the same time.
Not surprising. Aircraft are "flight followed" by a series of control centers across the nation, each responsible for a given chunk of airspace. Something happening in an area controlled by Center "A", for example, wouldn't be passed on to Center "B" (which has it's own problems to work) unless it impacted Center "B". Furthermore, unless someone TELLS Center they're being hijacked, there's no way for a controller - looking at
a blip - to know what's up. And any controller can tell you that pilots do
Somehow the people who did this managed to turn off the transponders on these planes. Normally a plane flying in controlled airspace squawks a unique id and altitude which is decoded by their radar and associated with each blip. Sometimes low cost homebuilts/ultralights fly with no transponder, but Boeings <sarcasm>usually</sarcasm> do. If you set a transponder to XXXXX, it means you're being hijacked.
BTW if you see your friend Jack at the airport, be sure to say, "What's up, Jack!" instead of "Hi Jack!"
So how do you deal with this? Blowing up a whole country? I wonder if the US should adopt a 'fire w/ fire' approach and invest in intelligence, covert ops and assassinations. It would seem that it is open season on terrorism by every democratic nation, I expect to see very conspicuous Samuel Jackson style ass whoopins on whiny extremist groups to satiate America's anger. Terrorize the terrorists.
Oh yeah, obviously Echelon should probably have MacOS loaded on it.
-b
Also sprach Leigh Anne Chisholm
I despise posting off-topic, but I want to say two things...
1. If a transponder is turned off, it doesn't mean that you don't show up on radar--a blip appears on the radar screen as long as you're high enough to be detected. If however you fly low enough, you can fly below the radar's detection capability. I don't offhand recall what height that is--it's been years since I was active as a pilot and prospective Air Traffic Controller.
That would depend on the distance from the transmitter...the farther from the transmitter, the higher you could fly and not be detected. Another issue is the efficiency of the transmitter and receiver at picking up the reflected energy. From what I understand, air traffic control radars are, in this day and age, really quite pathetic as true radars. They largely depend on transponder responses to be able to pick up aircraft, as even fairly large aircraft, at some distance from the transmitter, may only give a secondary (transponder) return, and not a primary (reflected energy) return. -- Jeff McAdams Email: jeffm@iglou.com Head Network Administrator Voice: (502) 966-3848 IgLou Internet Services (800) 436-4456
It is my understanding that the planes were _always_ on Radar, but that without the transponder, the altitude of the planes was unknown. DJ -----Original Message----- From: owner-nanog@merit.edu [mailto:owner-nanog@merit.edu]On Behalf Of Leigh Anne Chisholm Sent: Thursday, September 13, 2001 5:11 PM To: Borger, Ben; nanog@merit.edu; Hire, Ejay Subject: RE: Analysis from a JHU CS Prof I despise posting off-topic, but I want to say two things... 1. If a transponder is turned off, it doesn't mean that you don't show up on radar--a blip appears on the radar screen as long as you're high enough to be detected. If however you fly low enough, you can fly below the radar's detection capability. I don't offhand recall what height that is--it's been years since I was active as a pilot and prospective Air Traffic Controller. 2. What's the point of having transponder codes for hijacking if they're so well published everyone is aware of them? The purpose of the codes was so that the pilot could communicate this information without the hijacker becoming aware of what was happening. I have always REALLY DISLIKED the now common practice of advertising this information. You're taking away one of the pilot's best tools... -- Leigh Anne
-----Original Message----- From: owner-nanog@merit.edu [mailto:owner-nanog@merit.edu]On Behalf Of Hire, Ejay Sent: Thursday, September 13, 2001 2:35 PM To: 'Borger, Ben'; 'nanog@merit.edu' Subject: RE: Analysis from a JHU CS Prof
The transponders, like most avionics, has a handy-dandy off switch.
-----Original Message----- From: owner-nanog@merit.edu [mailto:owner-nanog@merit.edu]On Behalf Of Borger, Ben Sent: Thursday, September 13, 2001 2:32 PM To: 'nanog@merit.edu' Subject: FW: Analysis from a JHU CS Prof
At 06:05 PM 9/12/2001, you wrote:
Quite more interesting is why nobody noticed that 4 airliners where hijacked almost the same time.
Not surprising. Aircraft are "flight followed" by a series of control centers across the nation, each responsible for a given chunk of airspace. Something happening in an area controlled by Center "A", for example, wouldn't be passed on to Center "B" (which has it's own problems to work) unless it impacted Center "B". Furthermore, unless someone TELLS Center they're being hijacked, there's no way for a controller - looking at
a blip - to know what's up. And any controller can tell you that pilots do
Somehow the people who did this managed to turn off the transponders on these planes. Normally a plane flying in controlled airspace squawks a unique id and altitude which is decoded by their radar and associated with each blip. Sometimes low cost homebuilts/ultralights fly with no transponder, but Boeings <sarcasm>usually</sarcasm> do. If you set a transponder to XXXXX, it means you're being hijacked.
BTW if you see your friend Jack at the airport, be sure to say, "What's up, Jack!" instead of "Hi Jack!"
So how do you deal with this? Blowing up a whole country? I wonder if the US should adopt a 'fire w/ fire' approach and invest in intelligence, covert ops and assassinations. It would seem that it is open season on terrorism by every democratic nation, I expect to see very conspicuous Samuel Jackson style ass whoopins on whiny extremist groups to satiate America's anger. Terrorize the terrorists.
Oh yeah, obviously Echelon should probably have MacOS loaded on it.
-b
On Thu, Sep 13, 2001 at 03:11:15PM -0600, Leigh Anne Chisholm wrote:
2. What's the point of having transponder codes for hijacking if they're so well published everyone is aware of them? The purpose of the codes was so that the pilot could communicate this information without the hijacker becoming aware of what was happening. I have always REALLY DISLIKED the now common practice of advertising this information. You're taking away one of the pilot's best tools...
Then you would probably consider it a good thing that the code he gave is not, in fact, the transponder code for hijacking. And no, I'm not going to detail what the correct one is. Go ask a pilot (such as the one living in my house), if you want to know. Pretty much all of them know it; even those who don't fly planes one could reasonably hijack. -- *************************************************************************** Joel Baker System Administrator - lightbearer.com lucifer@lightbearer.com http://www.lightbearer.com/~lucifer
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 It's a moot point anyway, it's pretty clear the hijackers had flight training of some sort AND were well organized, and would be familiar with the steps that the pilots would take. Regards, Matt - -- Matt Levine @Home: matt@deliver3.com @Work: matt@easynews.com ICQ : 17080004 PGP : http://pgp.mit.edu:11371/pks/lookup?op=get&search=0x6C0D04CF - -----Original Message----- From: owner-nanog@merit.edu [mailto:owner-nanog@merit.edu] On Behalf Of Joel Baker Sent: Thursday, September 13, 2001 6:05 PM To: nanog@merit.edu Subject: Re: Analysis from a JHU CS Prof On Thu, Sep 13, 2001 at 03:11:15PM -0600, Leigh Anne Chisholm wrote:
2. What's the point of having transponder codes for hijacking if they're so well published everyone is aware of them? The purpose of the codes was so that the pilot could communicate this information without the hijacker becoming aware of what was happening. I have always REALLY DISLIKED the now common practice of advertising this information. You're taking away one of the pilot's best tools...
Then you would probably consider it a good thing that the code he gave is not, in fact, the transponder code for hijacking. And no, I'm not going to detail what the correct one is. Go ask a pilot (such as the one living in my house), if you want to know. Pretty much all of them know it; even those who don't fly planes one could reasonably hijack. - -- ********************************************************************** ***** Joel Baker System Administrator - lightbearer.com lucifer@lightbearer.com http://www.lightbearer.com/~lucifer -----BEGIN PGP SIGNATURE----- Version: PGPfreeware 7.0.3 for non-commercial use <http://www.pgp.com> iQA/AwUBO6EwS8p0j1NsDQTPEQJ4MACg/rVnB3BwbzLW70NBNY0MxigFyjgAoLJ4 b0EVfRCBWRyA3LnGzB2pGsZm =eZ+e -----END PGP SIGNATURE-----
On Thu, 13 Sep 2001, Matt Levine wrote:
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1
It's a moot point anyway, it's pretty clear the hijackers had flight training of some sort AND were well organized, and would be familiar with the steps that the pilots would take.
Regards, Matt
Since most commercial aircraft have multiple transponders, it should be assumed that if an aircraft stops squacking, something is BAD WRONG. Beyond this, the ability of the flight crew (any of them) to push a "panic" button that would cause the transponder to squack a predetermined distress code may me a good measure to implement. This "Panic" button should NOT provide any visible confirmation in the flight-deck instrumentation but instead, the ATC should in some cryptic form acknowledge the fact that the aircraft is in distress via radio communications. (perhaps a minor heading correction that is not needed, etc.) --- John Fraizer EnterZone, Inc
Leigh Anne Chisholm wrote:
I despise posting off-topic, but I want to say two things...
1. If a transponder is turned off, it doesn't mean that you don't show up on radar--a blip appears on the radar screen as long as you're high enough to be detected. If however you fly low enough, you can fly below the radar's detection capability. I don't offhand recall what height that is--it's been years since I was active as a pilot and prospective Air Traffic Controller.
That depends. The FAA has begun removing "Primary Target" service from some of it's control center, citing cost-savings, etc. Some ARTCC and TRACON facilities (Air Route Traffic Control Center and Terminal Radar Approach Control) have primary-target capabilities on their scopes, some do not. Some of the recording systems record the primary targets, some do not. As to the height at which you are undetectable, there are so many determining factors, that it's on a location by location basis. Factors include height of the antenna, terrain, distance from the antenna, number of radar sites covering the area (yes, there is an overlap in most of the US these days), etc. For example, I know bay can see me on the ground at PAO if I leave my transponder on. However, Oakland Center can't see me in some parts of Northern CA if I drop below 12,000 feet MSL (~4000 AGL in some of those areas).
2. What's the point of having transponder codes for hijacking if they're so well published everyone is aware of them? The purpose of the codes was so that the pilot could communicate this information without the hijacker becoming aware of what was happening. I have always REALLY DISLIKED the now common practice of advertising this information. You're taking away one of the pilot's best tools...
Yes and no. There was a time when this was so poorly publicized that many of my fellow pilots didn't know that there was a hijack code. The fact is, this has always been published in the AIM, so anyone who cared could easily pick up a copy of the AIM (Airmans Information Manual) at their local pilot shop and find out. I don't think the knowledge of the code necessarily prevents the pilot from using it. Any hijacker that's going to know about the code from any publicity it may have will already know enough to turn the transponder off anyway for other reasons.
-- Leigh Anne
Owen DeLong PP ASEL, Instrument Airplane
-----Original Message----- From: owner-nanog@merit.edu [mailto:owner-nanog@merit.edu]On Behalf Of Hire, Ejay Sent: Thursday, September 13, 2001 2:35 PM To: 'Borger, Ben'; 'nanog@merit.edu' Subject: RE: Analysis from a JHU CS Prof
The transponders, like most avionics, has a handy-dandy off switch.
-----Original Message----- From: owner-nanog@merit.edu [mailto:owner-nanog@merit.edu]On Behalf Of Borger, Ben Sent: Thursday, September 13, 2001 2:32 PM To: 'nanog@merit.edu' Subject: FW: Analysis from a JHU CS Prof
At 06:05 PM 9/12/2001, you wrote:
Quite more interesting is why nobody noticed that 4 airliners where hijacked almost the same time.
Not surprising. Aircraft are "flight followed" by a series of control centers across the nation, each responsible for a given chunk of airspace. Something happening in an area controlled by Center "A", for example, wouldn't be passed on to Center "B" (which has it's own problems to work) unless it impacted Center "B". Furthermore, unless someone TELLS Center they're being hijacked, there's no way for a controller - looking at
a blip - to know what's up. And any controller can tell you that pilots do
Somehow the people who did this managed to turn off the transponders on these planes. Normally a plane flying in controlled airspace squawks a unique id and altitude which is decoded by their radar and associated with each blip. Sometimes low cost homebuilts/ultralights fly with no transponder, but Boeings <sarcasm>usually</sarcasm> do. If you set a transponder to XXXXX, it means you're being hijacked.
BTW if you see your friend Jack at the airport, be sure to say, "What's up, Jack!" instead of "Hi Jack!"
So how do you deal with this? Blowing up a whole country? I wonder if the US should adopt a 'fire w/ fire' approach and invest in intelligence, covert ops and assassinations. It would seem that it is open season on terrorism by every democratic nation, I expect to see very conspicuous Samuel Jackson style ass whoopins on whiny extremist groups to satiate America's anger. Terrorize the terrorists.
Oh yeah, obviously Echelon should probably have MacOS loaded on it.
-b
-- *********************************************************************** "Every time you turn on your new car, you're turning on 20 microprocessors. Every time you use an ATM, you're using a computer. Every time I use a settop box or game machine, I'm using a computer. The only computer you don't know how to work is your Microsoft computer, right?" - Scott McNealy, CEO of Sun Microsystems, Inc., from an April 1997 interview in Upside Magazine *********************************************************************** "One World, One Web, One Program." - Microsoft Promotional Ad "Ein Volk, Ein Reich, Ein Führer" - Adolf Hitler
On Thu, Sep 13, 2001 at 03:31:37PM -0500, Borger, Ben wrote:
Somehow the people who did this managed to turn off the transponders on these planes. Normally a plane flying in controlled airspace squawks a unique id and altitude which is decoded by their radar and associated with each blip. Sometimes low cost homebuilts/ultralights fly with no transponder, but Boeings <sarcasm>usually</sarcasm> do. If you set a transponder to 7500, it means you're being hijacked.
Some obvious things to do: 1) Turn off altitude reporting -- most of the transponders I've used have 3 settings (off, on, and on with altitude reporting) 2) Then sqwak VFR. 3) Turn the transponder off 4) Pull the breaker. (All flight avionics are on resettable breakers, accessible to the flight crew. There is good reason for this.) I wouldn't find it exactly surprising that any of the transponders had been switched off. It only takes a moment. --msa
participants (9)
-
Borger, Ben -
Deepak Jain -
Jeff Mcadams -
Joel Baker -
John Fraizer -
Leigh Anne Chisholm -
Majdi S. Abbas -
Matt Levine -
Owen DeLong