Planes of 911 Exceeded Their Software Limits

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I stumbled across this on Digg this morning, but haven't had a chance to research it at all.

http://www.truthbox.org/index.php?option=com_content&task=view&id=34&Itemid=2

I'm initially a bit wary due to the lack of references in the article, but research may end up validating the claims made.

Two of the aircraft exceeded their software limits on 9/11.The Boeing 757 and 767 are equipped with fully autonomous flight capability, they are the only two Boeing commuter aircraft capable of fully autonomous flight. They can be programmed to take off, fly to a destination and land, completely without a pilot at the controls.
The cell phone calls from the aircraft could not have happened. I am a National Security Agency trained Electronic Warfare specialist, and am qualified to say this. My official title: MOS33Q10, Electronic Warfare Intercept Strategic Signal Processing/Storage Systems Specialist, a highly skilled MOS which requires advanced knowledge of many communications methods and circuits to the most minute level. I am officially qualified to place severe doubt that ordinary cell phone calls were ever made from the aircraft.

It was impossible for that to have happened, especially in a rural area for a number of reasons.

When you make a cell phone call, the first thing that happens is that your cell phone needs to contact a transponder. Your cell phone has a max transmit power of five watts, three watts is actually the norm. If an aircraft is going five hundred miles an hour, your cell phone will not be able to 1. Contact a tower, 2. Tell the tower who you are, and who your provider is, 3. Tell the tower what mode it wants to communicate with, and 4. Establish that it is in a roaming area before it passes out of a five watt range. This procedure, called an electronic handshake, takes approximately 45 seconds for a cell phone to complete upon initial power up in a roaming area because neither the cell phone or cell transponder knows where that phone is and what mode it uses when it is turned on. At 500 miles an hour, the aircraft will travel three times the range of a cell phone's five watt transmitter before this handshaking can occur. Though it is sometimes possible to connect during takeoff and landing, under the situation that was claimed the calls were impossible. The calls from the airplane were faked, no if's or buts.
The reference to the author's NSA official title makes me a bit wary, though the comments about cellphone handshaking sounds plausible.

Comments?
 
That this explanation is false is trivially proven. Get a stopwatch and a cell phone. Start the stopwatch and turn on the cell phone at the same time. As soon as the cell phone "boots up" make a phone call. As soon as you press send, stop the stopwatch.

Note that this time is very much smaller than 45 seconds.

The real explanation behind the inability to make a cell phone call in a plane moving at 500 mph is the doppler shift of the RF carrier. Cell phone channels are very closely spaced and the doppler shift could put the cell connection on the "wrong channel". Not only is this a problem but both the magnitude and direction (i.e. higher or lower) of doppler shift would change as the angle between the cell phone and the tower changes during flight.

The fact that the author completely misrepresented the situation in a way that is trivially disproven strongly suggests that the author is not credible.

Also, the radiation limit of cell phones is three watts, not five. A five watt cell phone is simply running out of the FCC limits set for this service. This limit was achieved by the original cell phones that consisted of a handset and a carry-around box the size of a shoe box. This can (at least in principal) also be achieved by a cell phone built into a car.

However the modern Nokia or Motorola Razor comes nowhere close to three watts - maybe 300 milliwatts. Modern cell phones use much less power than the initial generation because there are 100X as many cell towers to contact, and therefore the power needed is so much less. In addition modern cell phones are digital not analog and so need less power to achieve the same Signal/Noise ratio.

Trust me, you would not wish to carry around a three watt cell phone. Either the battery would be humungeous or the talk time would be measured in minutes or both.

Sorry Mr. MOS33Q10, Electronic Warfare Intercept Strategic Signal Processing/Storage Systems Specialist but you are fulla bulla.
 
I did a bit of digging and found similar discrepancies with other points referenced in the article. I still, however, consider myself something of a newbie in the art of discernment, so if anything, I'll take this as another learning experience. It's nice to know that I'm starting pick up on what to watch out for.

The real explanation behind the inability to make a cell phone call in a plane moving at 500 mph is the doppler shift of the RF carrier. Cell phone channels are very closely spaced and the doppler shift would put the cell connection on the "wrong channel". not only this but the degree of doppler shift would change as the angle between the cell phone and the tower changes during flight.
I wasn't aware of this, but I'll tuck it away in mental rolodex for future reference.
 
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