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Norad

Thanks Gumboot. That was a good read. And thanks Psi for revising what you think when presented with new compelling evidence. You may or may not be a truther but thats something they don't often do.
 
psy kick said:
David Icke almost had me convinced. See, I hadn't known about radar or transponders but thought maybe Icke did.
Heck, when I first read Krassner's The Parts Left Out of the Kennedy Story, I believed it!
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Dude, most kooks think David Icke is a Kook!
 
Ivan The Song Boy said:
Yes, I had read a number of times about the ground clutter problem for NORAD. It occurs to me now, that a secondary target on the FAA side going dark could make it either easier to track or harder, depending upon the gear.
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One thing worth contemplating is that the FAA planned to deactivate all primary surveillance radars in the late 1990s and run on secondary only. They only (reluctantly) stalled after some very loud protests from the military, and in the months before 9/11 they were again moving ahead with shutting down the primary radar network.

The implications of this, for 9/11, are pretty profound - without primary coverage no one would have had the faintest idea what was going on until the entire attack was over.



Ivan The Song Boy said:
If a jet goes from their current squawk code to VFR {1200} they are still secondary, but if they go dark all together the ATC'er has to either literally move to a different screen or in some cases, they can switch the scoop in front of them to primary?
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The scopes actually simultaneously display primary and secondary, however the Radar Data Processor filters out primary-only returns on a normal basis, only displaying primary returns that are "bonded" to a secondary return. They can easily "turn on" full primary coverage (really it's more a case of turning off the filter) with the flick of a switch or turn of a knob or whatever, so it literally takes only a moment, and they can pick up the aircraft because it will be on the screen exactly where it just left.


Ivan The Song Boy said:
So, my earlier comment about having to find these jets in a "sea of jets" is probably wrong.. The problem is different than that.
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Yeah this was a misconception from the media. It wasn't the FAA that had to find the aircraft in a "sea of jets", it was more NORAD that had to find the aircraft in a "sea of jets and ground clutter".
 
Ivan The Song Boy said:
I mean, how many primary targets will there be? Some for sure on a beautiful September morning but NONE at that air speed.
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Gumboot, you've probably been through the FDR data more in-depth than any of us. Did they maintain a cruising speed prior to going terminal? I would think that they would want to maximize the amount of fuel in the tanks when they hit, and opening up to 500kts at low altitude the entire way would probably chew up some gas.

If they did maintain normal cruising speed, ATC personnel would have had a Sisyphean task to try to pick out those particular flights using only radar returns without XPNDR information.
 
psy kick said:
Lady, not dude. :)
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My mistake, I was going by your Avatar :) Icke is still a kook though. The guy thinks the world is run by shape shifting space reptilian aliens! I swear the guy watched V to many times while stoned and thought it was a documentary.
 
I remember V. Its interesting how his mind works though.
Thank you guys for making sense.
 
JoeyDonuts said:
Gumboot, you've probably been through the FDR data more in-depth than any of us. Did they maintain a cruising speed prior to going terminal? I would think that they would want to maximize the amount of fuel in the tanks when they hit, and opening up to 500kts at low altitude the entire way would probably chew up some gas.

If they did maintain normal cruising speed, ATC personnel would have had a Sisyphean task to try to pick out those particular flights using only radar returns without XPNDR information.
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The flights generally sat around 300-350KT.

Just to reiterate; UA175's transponder was never turned off.
ATC had no problem tracking UA93 or AA11 (until they flew below radar coverage)
AA77 was the only flight that tracking proved a problem for, and that was because it was hijacked in a secondary-only area.
 
gumboot said:
The flights generally sat around 300-350KT.

Just to reiterate; UA175's transponder was never turned off.
ATC had no problem tracking UA93 or AA11 (until they flew below radar coverage)
AA77 was the only flight that tracking proved a problem for, and that was because it was hijacked in a secondary-only area.
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Duly noted, and many thanks.
 
Indeed. Good info here.. It seems that the only other primary targets would be small aircraft who had not requested what is called "flight Following".. ATC will help you along and hand you off as needed even if you have no flight plan, but you have to ask, and officially, if they're to busy, they can deny. {you almost always get it if you want it}.. There are also speed restrictions of 250 kts under 10,000 feet MSL so it seems any target at 350 kts would be easy to spot, and there would not be many, if any at those speeds. Most small aircraft are in the 90-to- 180 kts speed range, even most twins. Anyone in the 300 kt speed range would have certainly filed an IFR flight plan and been assigned a transponder code on the ground. This would narrow it down pretty quick, I would think.

Ivan...............
 
They weren't below 10,000 feet until they were into the ground clutter though, and as noted above, the FAA knew where 3 of them were throughout their entire flight so they didn't have to pick them out. Also planes on Pimary radar don't have Alttiudes attached, that is a function of the Secondary Radar, which they lost in 2 cases. NORAD of course had none of that information to start with, they just had 1-2000 dots moving on the screen, plus additional ground clutter.
 
PhantomWolf said:
They weren't below 10,000 feet until they were into the ground clutter though, and as noted above, the FAA knew where 3 of them were throughout their entire flight so they didn't have to pick them out. Also planes on Pimary radar don't have Alttiudes attached, that is a function of the Secondary Radar, which they lost in 2 cases. NORAD of course had none of that information to start with, they just had 1-2000 dots moving on the screen, plus additional ground clutter.
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I'm a little ignorant of the type of radar we're talking about here...from what you described it sounds like Primary radar is 2D, secondary is 3D. That about right?
 
Primary Radar is the pure radar return from the skin of the aircraft. Secondary Radar is the return from the system interrogating the aircraft transponder and thus getting things like the exact location, flight information, heading, and altitude which are then tagged onto the primary radar.
 
PhantomWolf said:
Primary Radar is the pure radar return from the skin of the aircraft. Secondary Radar is the return from the system interrogating the aircraft transponder and thus getting things like the exact location, flight information, heading, and altitude which are then tagged onto the primary radar.
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I get that the secondary should be able to give you altitude via Mode C of the transponder...what I would call IFF. I understand the interrogation giving you flight number and all sorts of other stuff...

I guess what I didn't know was if their actual RADAR system which is ARTS if im not mistaken, can give you altitude...apparently it only gives you azimuth and range. Never mind.
 
Here we go...

155794934e3a05e016.jpg


Cheap Shot might be able to tell us if this is accurate to their system, but what the image depicts is a basic ATC Radar Screen. The returns you see with the data attached are from Transponders. That is Secondary Radar. Primary would just be a bunch of blips. You can see the Altitude shown in the Transponder data.
 
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PhantomWolf said:
Here we go...

Cheap Shot might be able to tell us if this is accurate to their system, but what the image depicts is a basic ATC Radar Screen. The returns you see with the data attached are from Transponders. That is Secondary Radar. Primary would just be a bunch of blips. You can see the Altitude shown in the Transponder data.
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This is actually very similar in principle to the display used onboard Navy ships for track sharing/correlation. We could also interrogate transponders, which was a godsend for finding out whether or not an air contact was "one of ours." We didn't have to depend on Mode C for altitude data, though. Most of the fleet air search radars, like the SPY-1D and SPS-48, are 3D. Range, Bearing, Altitude.

Wow, just seing that picture brought back memories of staring for hours on end at a screen drinking coffee by the gallon... :D
 
JoeyDonuts said:
This is actually very similar in principle to the display used onboard Navy ships for track sharing/correlation. We could also interrogate transponders, which was a godsend for finding out whether or not an air contact was "one of ours." We didn't have to depend on Mode C for altitude data, though. Most of the fleet air search radars, like the SPY-1D and SPS-48, are 3D. Range, Bearing, Altitude.

Wow, just seing that picture brought back memories of staring for hours on end at a screen drinking coffee by the gallon... :D
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Ahhh. From what I understand from Cheap Shot the initial reason they contacted NEADS was to try and gain altitude informtion so they knew who to clear out of the way of AA11.
 
PhantomWolf said:
Ahhh. From what I understand from Cheap Shot the initial reason they contacted NEADS was to try and gain altitude informtion so they knew who to clear out of the way of AA11.
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Interesting, but I could have sworn I've seen somewhere that the RADAR system that feeds NEADS/NORAD is pointed outward, not inward...

Does NEADS have a way of correlating altitude information to civilian ATC tracks who are not getting secondary (interrogation) return? :confused:
 
ARSR-1E, ARSR-2 and ARSR-3 radars do not have height finding capability. (These are long range primary surveillance radars utilised by the FAA).

The ARSR-4 has height-finding capability, and is used at JSS (Joint Surveillance System) sites around the perimeter of the USA. These are fed to FAA facilities, and then to NORAD facilities. However while the FAA cannot utilise their height-finding capability, NORAD can.

The initial calls from Boston ARTCC to NEADS were an attempt to get NEADS to use their ARSR-4 feeds to establish AA11's altitude.

All of the radars have a 360 degree coverage area, with a range of about 200nmi (at 60,000ft), so NORAD could see inland about 200nmi and out to see about 200nmi. However, the system was configured for maximum detection over water, thus was amplified. This increased ground clutter on the inland portion of the radar coverage, rendering it impossible to detect a primary contact. The "outward looking radar" is a simplified way of explaining the situation to a layman.

Due to the obsolete nature of NORAD's equipment on 9/11, it was impossible for the NORAD and FAA radar/computer systems to share data. I believe a thorough upgrade of NORAD's systems was implemented after 9/11 and digital linking between NORAD and FAA is strongly establish, however the specific details of this are no doubt classified. I do know from several articles that now when an aircraft on the FAA system goes NORDO it is automatically tagged on the NORAD system.
 
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