i read in a popular science magazine that stealth planes are useless when it comes to cell phones. it had something to do with multiple receivers or something. this was a potential threat and it can easily reveal the plane's exact location. if anybody has more info, plz post it here.

There is information around on it, I am sure a search will turn up more.

The stealth plane that went down in Bosnia was located by the use of cell phones, so I read....

damn.....our stealth tech sucks!
if u need me, i'll be in my backyard radioing positions of stealth planes to north korea.
jk

I am already waiting when the enemies like North Korea start using this technology and begin shooting down eagles, hawks, crows and atmospheric disturbances. . Some people don't realize cell phones are not the best deal for detecting aricrafts.

cell phones arent powerful enough to reach the alttitudes that the b-2 and especiallythe f-22 operate at, while the f-117 could just fly higher. In a war, isnt the power the first thing cut off? The cell towers dont work and so cell phones dont work.

It is my informed understanding that no one should take much stock in the claim that cell phone equipment can be used to track VLO aircraft.

While, in theory, it is possible to DETECT the presence of a VLO target by using conventional VHF/UHF cell phone equipment that has been heavily modified, that system could not possible localize or track said VLO target. And it certainly could not provide accurate information sufficient to provide a fire control solution to an AAA weapon system.

The use of bistatic radar systems, VHF frequencies, and exploiting the natural resonance phenomenae of air targets in nothing new. To make it work, you need a huge system (which is usually stationary and therefore susceptable to countermeasures), massive computing horsepower, and clear frequencies devoid of jamming. Most warfighters know this is a recipe for failure.

A lab and the real world are VERRY different, and what might work in one might not work in the other.

Originally posted by roniii259
A lab and the real world are VERRY different, and what might work in one might not work in the other.

Roniii259, you're right, as has been proven many times when something works in the lab but is either impractical or cost-prohibitive in the real world. On the other hand, if it's true that the F-117 was brought down in part by detection through cellular signal interruptions then we have a real-world scenario proving this to be plausible. Supposedly Roke started their work based on this. So far I've only found discussion boards through my searches so I don't yet fully believe the theory on the F-117. Does anyone have an authoritative site for this theory?

The f-117 shoot down was probably a lucky shot from an AAA battery that distrupted the RCS flow over the plane allowing a SAM to be fired. If even one hit and the plane will light up like a X-mas tree on radar

Originally posted by roniii259
The f-117 shoot down was probably a lucky shot from an AAA battery that distrupted the RCS flow over the plane allowing a SAM to be fired. If even one hit and the plane will light up like a X-mas tree on radar

It's been stated that the 117 was shot down due to a barrage of SAM fire in the general zone where it was flying. You could be on to something there.

The Checkoslavakians and French have a multihomed radar system that could possibly be used to detect current and near future stealth aircraft.

Basically the system works by having 12 - 20 radar receivers, and 5-7 transmitters, all positioned over 20 square miles of terrain. The transmitters send out radar waves, which the stealth aircraft deflects.

Current methods of stealth are designed to minimise the radar return directly to the transmitter, they scatter the radar instead of reflecting it back. In this case, that scatter can be used to detect the aircraft because you have a number of transmitters and receivers, all listening for the same thing, all knowing where their own transmitters are, and thus they can pinpoint the flying object that is causing scatter.

These type of systems can only work when very closely tied in together, the receivers need to know precisely (down to meter accuracy, GPS comes in handy here which is partially why the US retains the ability to degrade GPS signals using a system called Selective Availability) where the transmitters are, and a specific pulse band signal needs to be injected into the radar beam so the receivers can determine time of origin.

When you think about it, these types of systems are already in wide usage, but against submarines! Yes, its a huge leap to pit it against aircraft, but theoretically at least, it could work.

Originally posted by titian

Originally posted by roniii259
The f-117 shoot down was probably a lucky shot from an AAA battery that distrupted the RCS flow over the plane allowing a SAM to be fired. If even one hit and the plane will light up like a X-mas tree on radar

It's been stated that the 117 was shot down due to a barrage of SAM fire in the general zone where it was flying. You could be on to something there.

Actually, this case was due to two things:

1. The US using exactly the same insertion route for bombing missions several days in a row. THis gave the Serbians enough time to setup a SAM trap using 20 to 30 GRAIL launchers, there were at least 20 missiles in the air at the time the F117 was downed.

2. The Serbians knew the F117 was coming, due to the fact they had a sympathiser within the Nato command room at the time the mission was being planned. This gave them the exact time the mission was being planned for, but no routing details or knowledge that it was a F117.

Together, this enabled the Serbians to plan ahead and get ready well in advance. With 20 - 30 missiles in the air at the time, I doubt the F117s LO had much chance to come into play.

Altogether, a good show of what Intelligence can acheive. And a good show of what poor planning can cause.

How much $$ will that be? The Raptor will be at high altitude so the sscattering will probable not be near any recievers, while a tomahawk could be used to defeat a part of the system and stealth planes finishing it off.

How interesting that you bring this topic up. I was just having a conversation on the subject this morning with some experts in the radar and stealth fields. Their consensus is that cell phones being able to detect stealth aircraft is a myth. The power they put out is just too weak for any receiver to detect echoes off a low observable vehicle. While it may be theoretically possible to detect an object using such weak signals, the enormous size of the receiver antennas needed and the vast processing power required to differentiate a target from background noise and other interference are prohibitively expensive.

As for the F-117 lost over Kosovo, that had absolutely nothing to do with cell phones. As someone mentioned, missions were often flown using exactly the same route. The Yugoslavs were not able to track the aircraft, but simply sired salvo after salvo into that region of airspace and the F-117 was unlucky enough to fly into it.

Something people must remember is that stealth is about tactics as much as it is about technology. If you do the same thing over and over again, no matter how undetectable you are, the enemy will eventually catch on and be able to do something about it. The F-117 was not an example of stealth technology being defeated, but it was an example of poor mission planning.

[edit on 18-8-2004 by aerospaceweb]

Originally posted by RichardPrice
These type of systems can only work when very closely tied in together, the receivers need to know precisely (down to meter accuracy, GPS comes in handy here which is partially why the US retains the ability to degrade GPS signals using a system called Selective Availability) where the transmitters are, and a specific pulse band signal needs to be injected into the radar beam so the receivers can determine time of origin.

Selective Availability (SA) has been removed from the GPS signal because many commercial users had already figured out how to remove it anyway. In addition, Europe is about to launch its own GPS system called Galileo. The decision was made to remove SA before the European competitor comes into service so that Galileo doesn't appaer to be vastly superior to the existing system.

There are also a number of other applications for GPS that require a high level of accuracy. The FAA, for example, is developing a new civilian navigation system for commercial airlines called WAAS. You obviously want pretty good accuracy when you're using GPS to land a plane with 300 passengers aboard. SA was removed in order for systems like these to be developed.

Nevertheless, there is always the possibility that SA could be reinstated at any time. I believe it was reapplied to the Middle East during the opening stages of Op. Iraqi Freedom to deny Iraq access to the signal.

Originally posted by aerospaceweb




Selective Availability (SA) has been removed from the GPS signal because many commercial users had already figured out how to remove it anyway. In addition, Europe is about to launch its own GPS system called Galileo. The decision was made to remove SA before the European competitor comes into service so that Galileo doesn't appaer to be vastly superior to the existing system.

There are also a number of other applications for GPS that require a high level of accuracy. The FAA, for example, is developing a new civilian navigation system for commercial airlines called WAAS. You obviously want pretty good accuracy when you're using GPS to land a plane with 300 passengers aboard. SA was removed in order for systems like these to be developed.

Nevertheless, there is always the possibility that SA could be reinstated at any time. I believe it was reapplied to the Middle East during the opening stages of Op. Iraqi Freedom to deny Iraq access to the signal.

There has always been two levels of SA, one which was on all the time, and was eventually broken by independant vendors. This was turned off toward the end of the 1990s under order of President Clinton, for precisely the reason you stated.

The second level of SA is a fully different algorithm, and can be turned on for precise areas of the earth. If the US military is in a conflict, they can turn on L2 SA for just that theater of conflict, for example Iraq atm.

L2 has not been broken by vendors yet, and thus is still fully usable by the US military.

New GPS satellites will be able to focus the beam over a threat area to produce a more accurate, unjammable signal for the military while the enemy's GPS could be blocked, rendering a system dependant on it unussable