Without trying to start a tinfoil rally brigade here..


A guy at work has been spouting about a myth that I haven't heard about before.. with regards to 9/11. He said that someone did tests with regards to trying to use cell phones on planes, and that at above 8000 feet and going a few hundred miles an hour, you cannot get reception.. making the audio tapes bogus. I am thinking of picking up a wholesale load of tin foil for an early christmas present... but debunking this would be a lot more fun.

Unfortunately.. when I google for some information on how much bullshit is... all that I come up with are a few thousand pages on how all the myths are true.

Popular Mechanics has just released a "Debunking 9/11 Myths" book.. I think I'll pick it up next time I am at the store.

ETA:

After a bit more digging around.. I came across this:

www.loosechangeguide.com/lcg5.html

Thanks anyway.

Were the planes above 8k feet when the calls were made?

Quoted: Were the planes above 8k feet when the calls were made?

As far as I know they were?

This is the first I've ever heard of this, so I am at a loss to any logical reasoning.

Quoted: Cell phones are basically two way radios.  Those are line of site transmissions, at that altitude, the line of site would actually be enhanced, not degraded.

I believe you...

I just need some good, hardcore evidence to shove in his face.

Those are cell phones in the back of the headrests.

Setting aside the physics of private cellphone calls on an airplane - Todd Beamer and other passengers and crewmembers on Flight 93 used the plane's AIRFONES to place their calls and describe the hijacking in progress.




I for one am glad these 9-11 conspiracies are out there - it is one of the most glaring and obvious ways to identify an otherwise normal-looking BRAINWASHED MORON . Take note of the person and save that info for when you need it.

Quoted: Setting aside the physics of cellphone calls on an airplane - Todd Beamer and other passengers and crewmembers on Flight 93 used the plane's AIRFONES to place their calls and describe the hijacking in progress.

I found a nice/awesome/decent link above.

Cell phones are line of sight and power restricted… if you have a line of sight and enough power you can connect. I have connected on mountain tops that were miles away from the nearest tower but had a good line of sight.

Don't debate people who try to say these things.
Just tell them to fuck off.

Quoted: Don't debate people who try to say these things. Just tell them to fuck off.

Big time saver.

I have 13 yrs with Motorola in the wireless data and cell phone businesses. There is no problem getting cell phones to work in airplanes.

The issues are
- 800 MHz transmitters in some cell phones can interfere with the unshielded electronics (radio/navigation) in older aircraft. Hence the FAA rules about no wireless devices during the flight.

-It tends to freakout the network a bit. Many towers will sense your cell phone at the same time, and your handheld will handoff (or switch) between towers quickly.  They can handle it in most cases.

The height isn't an issue, you will have line of sight with many towers. The speed might lower the signal quality a bit, not enough to be a big deal.

Quoted: Quoted: Don't debate people who try to say these things. Just tell them to fuck off. Big time saver.

And fun, too.  

"Hey, did you know it was a cruise missle that hit the Pentagon?"  "Fuck off."

"Hey, did you know there were no passengers on the planes that hit the WTC?"  "Fuck off."

"Hey, did you know it was controlled demolition that brought down the towers?"  "Fuck off."

Turn the tables - you just get bogged down in nonsense and minutia if you try to argue this sort of crap. Ignore the details and go for the big picture: If 9/11 was a conspiracy, who were the conspirators, what were their goals, and why did they decide that the 9/11 attacks were the best way to achieve those goals?

I've never heard an answer to those questions that is more plausible then the widely-accepted explanation. Conspiracy theory nuts usually whip out something involving Halliburton and money for supposed Bush cronies. Of course, with all of the pork that .gov spews out, there's much easier ways to get payoffs for your cronies then using some impossibly complicated conspiracy to start a very politically expensive war. Meanwhile, Islamic terrorists have been attacking American interests for DECADES.

Ask the asshat to explain how the airplane's speed is a factor, and ask him if he knows the speed of propogation of radio waves.

Of course, he might be one of those genius' that think airplanes can't fly at night because the "air is dark".  [From a true story, youcan't make that stuff up.]

...or simply tell him to "fuck off".

I have already gotten a cell signal at 35,000 feet. Forgot to turn off my phone.

ETA: Cincinnatus still has the best reply.

I have extensive experiance with this, and have always wondered about the claims.

Here is the deal:

Depending on the type of phone and the location, sometimes you can get a cell to work for a short time at around 8000 and below.

High and fast they do not work.  I'm guessing it is because the cell cannot lock onto one particular tower.

Does anybody know what specific claims were made regarding calls?  Were they from the aircraft seatback payphones, or from cells, and what approx altitudes, and speeds were they made from?


It is quite possible that the ROPers flew the aircraft low.  Does anybody know?

BTW- the conspiracy people are idiots one and all.  If one of them tried to tell me in person that the ROP was not responsible, it would be very hard to remain calm and controlled.

Yeah, some people just can't accept the FACT that ISLAMOFACISTS want to kill us.  They have been doing it for years.

I look the nutcases that say stuff like this and remark, "You just don't get it, do you?"

It WAS a conspiracy...........
in that at least 19 people were involved...........




Scott

Quoted: I have extensive experiance with this, and have always wondered about the claims. Here is the deal: Depending on the type of phone and the location, sometimes you can get a cell to work for a short time at around 8000 and below. High and fast they do not work.  I'm guessing it is because the cell cannot lock onto one particular tower. Does anybody know what specific claims were made regarding calls?  Were they from the aircraft setback payphones, or from cells, and what approx altitudes, and speeds were they made from?

So my cell phone ringing at 35,000 feet and the flight attendant giving me the stink-eye never happened? I must have been dreaming.

Quoted: Those are cell phones in the back of the headrests.

I've flown a lot, and I have never seen a cell phone on the back of a headrest.  What airline was this?  What type of plane?  How did you know it was a cell phone rather than one of the standard proprietary RF or satellite units they usually have?  That is something very unusual if you did see one.z

Well, we installed an external antennae on a private plane so the owner could use his cell phone.

The only problem he had is that he was getting billed 3-4x for the same call since that many sites picked up the call.

All the calls were well above 8k'

If I learn one thing in life, "don't argue with someone who is crazier than you are."

Quoted: Quoted: Those are cell phones in the back of the headrests. I've flown a lot, and I have never seen a cell phone on the back of a headrest.  What airline was this?  What type of plane?  How did you know it was a cell phone rather than one of the standard proprietary RF or satellite units they usually have?  That is something very unusual if you did see one.z

Zoom is trying to tell you sarcastically that the seatback phones work through a central downlink and are completely different from cells.

Quoted: Quoted: I have extensive experiance with this, and have always wondered about the claims. Here is the deal: Depending on the type of phone and the location, sometimes you can get a cell to work for a short time at around 8000 and below. High and fast they do not work.  I'm guessing it is because the cell cannot lock onto one particular tower. Does anybody know what specific claims were made regarding calls?  Were they from the aircraft setback payphones, or from cells, and what approx altitudes, and speeds were they made from? So my cell phone ringing at 35,000 feet and the flight attendant giving me the stink-eye never happened? I must have been dreaming.

That can happen, and you may also be showing full bars, but the call will not go through.
Answer it next time and see for yourself.

Most digital cell towers provide coverage for about a 7 mile radius around the tower.  This would also mean the signal would go about 7 miles up.  Was the plane above 7 miles altitude when the calls were made?

Quoted: Quoted: Quoted: I have extensive experiance with this, and have always wondered about the claims. Here is the deal: Depending on the type of phone and the location, sometimes you can get a cell to work for a short time at around 8000 and below. High and fast they do not work.  I'm guessing it is because the cell cannot lock onto one particular tower. Does anybody know what specific claims were made regarding calls?  Were they from the aircraft setback payphones, or from cells, and what approx altitudes, and speeds were they made from? So my cell phone ringing at 35,000 feet and the flight attendant giving me the stink-eye never happened? I must have been dreaming. That can happen, and you may also be showing full bars, but the call will not go through. Answer it next time and see for yourself.

I did answer it. That is why I got the stink eye. I spoke to my coworker for about 30 seconds until the attendant got there.

One thing that is critical to understandingtrunking or cellular type  mobile radio communications are two factors:

Loop path timing
Doppler effect


Your cellular telephone,  whether it is an old analog phone,  or PCS, or GSM,  or any othe
r format,  essentially is a full duplex transceiver that works on a "trunking" type radio backbone.

Trunking is simply the assignment of a given communication to any available channel
within a pool of channels that the system uses.   Every time a transmission ceases and a
new one is initiated,  it can be and usually is assigned to a different channel within the
system.   The system uses a special channel known as a "control channel"  that all
subscriber units listen to when they are not currently assigned to a conversation.    This
special "control channel"  is responsible for managing every aspect of what the subscriber
units are doing. It handles the units logging in,  changing sites,  initiating calls, and
receiving calls.   It tells your radio to go to a given channel to receive a transmission that
is intended for you or your group of users.    

Every unit that's not busy goes "home" and listens to the control channel for further instructions.

While cellular systems are different in that there is no one control channel,  and instead
the control channel tasking is distributed among many channels,   the concept is still
appropriate for the purpose of this discussion.

Loop path timing addresses the response time between when the control channel sends
directions to a subscriber radio and the radio's response.    It's only going to be a few
milliseconds in most cases.    But there is only a limited window of time in which the
control channel and the radio can communicate.   The data that is exchanged between
the two units must often be well synchronized.   The control channel and subscriber unit
must be synced up in order to handshake properly.

As a result,  due to the delays caused by the speed of light,  there is only a limited
range in which these radios can properly connect into the system.   Even though the
signals are sufficiently strong for good performance,   if the two units are far enough
apart,  they won't be able to sync up and exchange data.

In the case of trunking radio systems like your police department probably uses,  the
maximum effective range between the radio and the site it's working off of is about 75
miles.  Beyond that,  it's not normally going to work no matter how good the signal
quality is.   The system needs to have certain timing parameters adjusted if it is
going to need extra range.

75 miles is a long way away.  8000 feet is NOTHING.   Even 35,000 feet is less than 7 miles.

The other issue is doppler shift.   You probably learned the essentials of doppler shifting
when you were at school so I won't bother to cover that here.   But it does apply to radio
transmissions of all types.   The faster the radio is travelling relative to the ground based
system's equipment,  the farther above the assigned frequency that the mobile unit will
be operating on, while conversely,  the mobile unit will hear the land based units as
operating at a lower frequency.

If the units are too far off frequency relative to each other,  they won't be able to communicate.

I tried to find a good online doppler shift calculator applet that would work in a
representative sample case,  but I didn't find one that was suitable for this purpose,
so I won't give any numbers but I will state that many aircraft fly too fast to be able to
utilize normal cellular sites.      For trunking radio systems used for law enforcement,  
their systems sometimes include specialized sites that are used ONLY by airborne units,
and even if a helicopter unit is put into service that has radios for a trunked system,
the system has to be tweaked to allow the helicopter's radios to operate properly.
And helicopters aren't THAT fast.


CJ

That is a stupid and illogical assertion.  As has been stated, cell phones are nothing more than two-way radios.  They send and receive control signals and modulated voice from cell tranmitter-receiver towers.  You can make calls from any altitude, as long as the signal strength is sufficient for the receive circuits at either end to process the voice embedded in the carrier.

Whomever told you that is full of shit.

Quoted: The airphones installed on place are not cell phones. They were ground station based, then satellite based. This is why you can make a call between Hawaii and Mainland USA, when there are no cell towers for a thousand miles.

I've made several cellphone-to-cellphone calls between Hawaii and mainland US before which means cellphones must also be satellite-based and so therefore can work at any altitude.

height=8

Quoted: height=8 Quoted: The airphones installed on place are not cell phones. They were ground station based, then satellite based. This is why you can make a call between Hawaii and Mainland USA, when there are no cell towers for a thousand miles. I've made several cellphone-to-cellphone calls between Hawaii and mainland US before which means cellphones must also be satellite-based and so therefore can work at any altitude.

The cell phone relays to the satellite through a local tower, not directly to the satellite (with the exception of special satellite phones of course).

Once again..."The Bright Shining Lie"

Debunking 9/11 myths is a noble but fruitless cause. These conspiracy nuts have had 5 years to see the light and/or produce empirical evidence of their own; they've done neither.

You'd be better off just kicking your conpiracy-nut coworker in the mansack and moving on.

n/t

so the last time i was flying and some lady was scolded for being on the phone, she wasnt really talking to anyone?


thats right ... some dumb lady decided to make a call mid-flight and didnt have a problem getting reception at whatever your standard cruising alt is ...

thats my proof.  i've seen it.