Study on cell phone use on airliners in flight ...

http://www.spectrum.ieee.org/mar06/3069

Too bad it has already been established as fact that this is impossible. :sarcasm:

It appears that the majority of their data was collected during take off and landing as these are the most critical times for RF interference with the avionics and on board computer systems.

Pretty neat idea hiding a frequency analyzer in the overhead compartment to determine if the call was made. I am guessing the analyzer was not recordable though because the computer was used to store the data and also to switch the frequency band, on the analyzer, to see if other calls were made.

Very good article.

"The race is on to enable airline passengers to make and receive cell phone calls in flight."

http://www.usatoday.com/money/biztravel/2004-07-19-aircells_x.htm



I guess it's impossible - or it's possible. I love the accurate technical information available to anyone with an internet connection.

that present technology doesn't work on planes? From the OP it is clear that safety is the issue - I am assuming this satellite technology doesn't
interfer with aircraft instruments.

(and apparently it is) then maybe you should slap LARED's wrist, too. :)

by the all powerful sarcasm smilie! ;-)

:sarcasm:

:freak:

My understanding is that the point of the new development is safety. A phone in the air knows it's a long way from the BTS, so it transmits on full power, which was really bad when old analogue phones (that were more powerful than the current ones) were used. One of the fixes is to install a repeater in the plane, so all the phones on board only send their signals a few feet to the repeater (meaning they transmit on low power and don't interfere with the instrumentation); the repeater then sends them down to a BTS on the ground on some sort of safe frequency.

It's a great dis info article that the government shills came up with.

Must have something to do with the Flight 93 movie that was on A&E last month. It opened a lot of eyes concerning one of the 911 illusions.

As any one in the 911 truth movement who's flown can tell you........cell phones don't work.



===============================================================
"Mom? This is Mark Bingham."
===============================================================

"On our tests, the airlines—which by agreement remain unnamed—imposed two simple requirements: that the test equipment fit easily in a carry-on bag and that it not be opened while passengers were on board."

How do we know the plane was not fitted to accommodate cell phones when the plane type and company is secret?

Gee, how useful. :sarcasm:

thanks for your constructive and well thought out contribution. :eyes:

Just playing devil's advocate. ;)

Why isn't it just straightforward to either prove or disprove the notion???

I think the only way much of the 9/11 debate will be settled is when Jamie and Adam of "Mythbusters" finally decide to do a segment dedicated to 9/11.

If only.

Some here assert that no reliable cell phone connection is possible for a plane traveling hundreds of miles per hour at high altitudes.

Project Achilles: Cell phone Experiments in a Light Aircraft
http://www.physics911.net/index.htm

In addition, according to the theory, the government has voice morphing technology that allows them to imitate any voice. Therefore, it is most likely cell phone calls made in the planes were faked on 9/11.

When Seeing and Hearing Isn't Believing
http://www.washingtonpost.com/wp-srv/national/dotmil/arkin020199.htm



Personally, I prefer to stick with what’s provable and that is the demolishing of WTC.

but this isn't quantum physics, it's not like the question of trying to discern both the position and speed of an atomic particle, y'know, where you then get into Heisenberg's Uncertainty Priciple or anything (although it often sounds like it).

It is a VERY straightforward question, either cell phones DO or DON'T work under the supposed conditions that they were used on 9/11.

Mythbusters to the rescue

that the alleged hijackers did not act like fanatical Islamic martyrs in Florida,
they hung out with Europeans, they used drugs, they trained at a CIA-and-drug-connected
airport.

if that is what you are trying to prove.
"Passengers are using cell phones, on the average, at least once per flight, contrary to FCC and FAA regulations, and sometimes during the especially critical flight phases of takeoff and landing"

The main safety concern seemed to be interference with landing navigational equipment, which is probably when people would be most likely to use them and that would be at a lower altitude than the cells in use on 9-11.
..."As a result, they admit to using prohibited devices and also to using permitted PEDs at prohibited flight phases, that is, during takeoff and landing. "

"Our data and the NASA studies suggest to us that there is a clear and present danger: cell phones can render GPS instrument useless for landings"

just more insight on a contentious issue.

Nice cherry picking by the way.

to pick a cherry. What does the OP have to do with 9/11?

I think.

to my original question... Then why would they do THIS?

http://www.usatoday.com/money/biztravel/2004-07-19-aircells_x.htm

if it isn't "safe"...

so that the cell phones do not interfere with navigation and are reliable. It's pretty obvious to me that cell phones have not been reliable at high altitudes before, regardless of the safety issue. But, their use may have been possible. Strange that there has been no investigation , if we had a "real" media, there would have been one.

Which also means that people should stop spewing that cell phones don't work on airplanes and that all of the calls made from the passengers to their loved ones on 9/11 aren't real.
I think that argument has been more than sufficiently invalidated.

and the original article implied that calls tended to be made toward landing, which would be at a lower elevation and lower speed.

http://www.post-gazette.com/headlines/20011028flt93mainstoryp7.asp

"Flight 93 was near cruising altitude when a system-wide message came over its monitor. United control warned pilots in the air of potential "cockpit intrusion" -- meaning some passenger might try to seize a plane."

"At some point -- the best estimation is about 40 minutes into the flight west -- at least three of the hijackers stood up and put red bandanas around their heads". (9:20) (Hijack time)

"Deena Burnett was waking up at her home in San Ramon, Calif. She'd gone down to the kitchen to fix breakfast for her three daughters. The phone rang. She recalls it was around 6:20 a.m. -- 9:20 Eastern time."(cell call time)

it doesn't say where the alleged "furtive" cell phone users are in terms of altitude or distance from destination...

were fake or were they made from the ground?

http://www.privateline.com/Cellbasics/AirCell.pdf

.5G 3G

AT&T Service
Sprint Service
Verizon Service

Personal Cell Phone Use Inflight

WAEA TC Presentation - Updated 11/12/02


Pros & Cons for Airborne Use

CON-

Poor rural coverage (1)
Requires complex and expensive airborne system
Doppler limited (speed)
Receive/Transmit (RT) timing limited (distance)
No air-to-ground network to match these technologies
More difficult issues for Electro Magnetic Interference (EMI)
Fractured market, no one format is emerging as dominant
finite life, 2-3 more evolutions before 3G interoperability(2)
Market presence only 12% (digital-only phones)


(1) Not an airborne issue



Pro-
Good urban coverage - high growth, pervasive (1)
Spectrally efficient (high capacity)
Market presence of 67% (dual-mode phones, all types)
Multiple levels for transmit power



http://www.cellular-news.com/story/8727.shtml

"Generally, wireless operating equipment can only work below a height of 4,000 meters. China Mobile is the first carrier to bring wireless applications to a level above 5,100 meters." (they put a tower on MT. Everest)

http://telephonyonline.com/wireless/mag/wireless_final_contact/

Final Contact - using cell phones on September 11, 2001
Wireless Review, Nov 1, 2001 by Betsy Harter
Excerpt:
"Calling From 30,000 Feet"

Because wireless networks are designed for terrestrial use, the fact that so many people were able to call from the sky brings into question how the phones worked from such altitudes.

Alexa Graf, AT&T spokesperson, said systems are not designed for calls from high altitudes, suggesting it was almost a fluke that the calls reached their destinations.



Z: Funny how rational people understanding of cell phone technology will bend their technological(scientific) understanding just because of something being repeatedly told to them by the media and government, isn't it?

BOTTOM-LINE___________they don't work.

I've spent hours looking for something like that on cell phones & planes, good job..welcome to the DU dungeon

This is another major issue. I found the following about it, it's a post taken from a site banned by DU, but you should be able to find it if you google any of the phrases in "".

"It is possible that calls made from the hijacked planes on 9/11 would have a better chance of getting through to 911 than a new phone would in an emergency today.

"I worked in the marketing department of a US cell phone company in 2001. At the time, Tri-Mode phones were standard. Tri-Mode phones received 2 types of digital as well as analog signals. By the time the company released its first digital only phones, many who previously enjoyed using their cellphones upgraded to find that they were unable to get a signal or maintain a connection. The following explains why:

"From "Will your cell phone reach 911?", Consumer Reports, 2/2003

"When your phone is in digital mode, it can work only with your home carrier (the company you use for service) for any call--including those to 911--unless the home carrier has a roaming agreement with another carrier. Phones that can work in both digital and analog modes give you more options. Analog provides that safety net for emergency calling. Indeed, the principal FCC regulation governing wireless 911 recognizes the importance of the analog mode. The regulation, which took effect in 2000, says that whenever a wireless phone dialing 911 in analog mode can't get through via its home carrier, that phone must seek another signal, even if it's from a competing carrier, to quickly establish a voice connection. The FCC concedes its rule is only a small step toward improving 911 service. Multinetwork phones, which are normally in a digital mode, aren't required to switch to analog to make a 911 call. There are no regulations for digital-only phones..."

"In other words, for phones trying to make 911 emergency calls using analog, cell carriers were required to seek out the nearest tower (even a competitors' tower if necessary) to quickly connect the call. There were no such requirements for phones attempting to connect to 911 using a digital signal. This actually did make a phone with analog a better bet for reaching 911. However, companies began phasing out analog, passively at first, after the FCC lifted requirements that they maintain the analog system in Fall of 2002.

"Among Consumer Reports conclusions:

"The FCC must ensure that digital phones are more compatible.
The FCC voted last fall to phase out its requirement that some wireless providers offer an analog backup signal. We think that was a mistake because the agency did not also require companies to make their digital technologies talk with one another. Simply allowing analog to fade away removes the principal common wireless language. In the end, you will have less assurance than you do now that your phone will get through to 911.

http://www.consumerreports.org/main/detailv2.jsp?CONTENT
%3C%3Ecnt_id=299615&FOLDER%3C%3Efolder_id=162691

"So attempting to make a call from a plane today using a newer technology cell phone isn't really a fair comparison. The analog system is patchier and discontinued in many places altogether; many phones only offer access digital now anyway. On 911, the callers on the hijacked craft were almost certainly off the digital network using a trimode (or lower quality) phone. When digital couldn't get through, their phones switched to analog which, at least in a 911 call, gave them a better chance of getting through.

"This still doesn't clear up how calls were made at altitudes over 8,000 ft (and possibly up to 30,000 ft).
"Thanks,"

I didn't know this. If many of the passengers really did have phones that would automatically switch to analogue mode, then it makes the calls a whole lot more likely.

Where were the planes relative to the ground when the calls were made? At what altitude?

If they were anywhere within a 100 miles of NYC it's likely the planes were at a low altitude and there were dozens of cell towers within just a few miles of the planes. As you approach NYC, the density of cells becomes unreal.

At 30,000+ feet I can see locking onto a cell could be a bit dicey but if the planes were under 10,000 feet when the calls were made then it doesn't seem like such a stretch to me.

Unless you have the location and altitude at the time the calls were made I just don't see you getting a satisfactory answer to this question.