Cell phone use on airplanes is not allowed because of the fear that the cell phone signals might interfere with cockpit instruments. This could cause confusion for the pilots possibly leading to disaster.

Firstly cell phones were banned in 1991 on FCC initiative in USA. The reason was a probable interference of cell phone with the aircraft's communication and navigation systems. But at that time there were no facts that can prove or disprove that statement. The ban could be considered as a private initiative of airlines and telecommunications companies, which didn't want to lose a revenue from the air-phones installed onboard. Look, a one-minute call in the air was much more expensive than a usual cell phone call and, naturally, people used a cheaper service when they had a choice. The situation was regulated in 1991. Ground carriers had no objections. But we should understand that cellular technologies were not widely spread at that time and revenue of carriers was quite sufficient. It wasn't necessary for them to find other sources to get benefit. However, later, evidences that cell phones interfere with airplane equipment appeared. Such companies as Delta, United and Continental proclaimed that sometimes mobile phones really interfere with compasses and even cabin pressure. Specialist in equipment negatively took this announcement and in 1996 U.S. Federal Aviation Administration asked nonprofit organization to research this problem. As a result of their study was an article, where the specialists said that cell phones didn't operate on airplane systems. They also confirmed that all the bans shouldn't be repealed because theoretically such interference could take place. Similar tests were made by airplane manufacturers (Boeing Co.and Airbus Industrie) and the results were also negative. The absence of evidences allows many countries not to restrict passengers to use mobile phones onboard. First alarm was set when cell phones became widely spread and equipment errors became more often but still there were no direct evidences. Till 2000 some of the countries didn't joint to the ban against cell phones but an air crash of the flight number LX 498 Crossair (Saab 340) considerably changed the situation. It was not far from Zurich on the 10. of January 2000. Ten passengers and a whole crew perished in that air crash. For a long time the results of flight recorders decoding were not announced but at last it was a sensation. One of the reasons of the crash was an SMS message, which was received by one of the passengers, and a next cell phone conversation. Navigation monitoring devices showed wrong data at that moment, what led to a crash. Comments of independent experts were not comforting, they said that crew could improve the situation but it also made a mistake and crash was inevitable. Everybody agreed that an airplane fortune depended on crew actions and crew professionalism after electrical systems stopped working. Those countries which hadn't joint to the ban before, hurried on to do it. After that this air crash was forgotten. http://www.mobile-review.com/articles/2002/plane-en.shtml

Several answers. in an airplane, transmitting on a cellphone is a danger to all onboard. most cellphones do not work when off the ground. some cellphones are satelitte phones. these phones are different. their signal is much stronger and definetely can interfere with the pilots onboard computer and operational controls of the aircraft. Satelitte and regular cellphones, can ignite an explosive device. regular cellphones, on the ground, satelitte cellphones in the air. hope this answers your question.

"Mythbusters" did an episode on this and their finding was that it is possible, tho' unlikely, that a cell phone could interfere with the aircraft electronics. Since it's not practical to test every type of cell phone on every type of aircraft, better safe than sorry, no cell phone use on an aircraft in flight.

All electronic equipment is forbidden to operate on commercial aircraft from the time the doors are closed until the pilot says it is safe to use them - usually above 10,000 feet altitude. The problem is the possibility of interference with the plane's own electronic equipment. Cell phones are a special case that are forbidden the entire time the plane is in flight. The problem is that your phone may be connecting to dozens if not hundreds of towers simultaneously because of your super high elevation. The land-based cell phone system is designed to automatically detect which tower is receiving your strongest signal and ignore whatever portion of your signal is also arriving at nearby towers at a lower level. Imagine what would happen if hundreds of airborne passengers flying over a given city tried to use their phones with each of them connecting to dozens of towers. The computers controlling the system would be overwhelmed with conflicts and nobody could talk - not even those with their feet on the ground.

The poster that spoke of the conflict with cell ground towers is absolutely right. Amateur Radio UHF band radios such as 2 meter, 440, and 1.2 Ghz are commonly used with signal extenders and amplifiers called "repeaters". Repeaters are always mounted at high elevations such as tall buidings and mountains. Disneyland's Matterhorn mountain has one at the summit. They work by taking the signal transmitted from the HAM, amplifying it (there are no FCC power limits, but there are practical considerations) And rebroadcasting the signal over a wide area making much longer distance transmissions possible. They are often "linked" systems, which means when a HAM activates a repeater, it activates a string of other towers, sometimes hundreds of miles in length, and spanning state lines. Hams have to be careful not to key a repeater at the same time as another person because the stonger signal is likely to win out drowning out others, and in some cases, triggering a time-out on the repeater. It's practice and good manners that keeps this down to a minimum. There are regional coordinators that make sure towers aren't operating too close on the radio spectrum to interfere with each other, important when the tower is broadcasting solo, over a long distance. This also keeps a linked system from being keyed in the wrong order. I have described this system because of the contrast with cell phones. Amateur radio is used for search and rescue and other emergency operations because of these differences. A handheld radio can operate in the woods where a cell can't because cell systems rely on relatively low power closely and strategically placed repeater systems that are controlled in such a way as to be transparent to the user, but very limited in range. As another poster noted, one tower "hands off" the radio telephone call to another tower as the user moves out of range of one and into the range of another. This is why there are dead zones where you lose signal. there are no overlapping "cells" of coverage in some areas, or the terrain makes it difficult to keep the overlapping cells reliable. Now to the heart of the matter. If you are flying at 30,000 feet in a 747, and you were to make a cell phone call successfully, it would activate every cell in range of the tower that took your call in a chain of tower power-ups. Further complicating the mess is the speed with which the jet is flying. In contrast, an amateur radio repeater tower would be overwhelmed by a transmission on its input frequency, but wouldn't pass the traffic on to other repeaters (in the majority of cases). The same is true, for different reasons, of emergency and commercial trunked radio systems. Cell systems by their nature have to function in a very one-size-fits-all fashion. Frankly, I think the "interfears with Avionics" argument is just plain bogus. Modern jets are easily the most sophisticated commercial machines being built. They have to be able to withstand every imaginable assault on their functioning, and be robust about it. If this argument were true, an hobbiest with a microwave communication dish system (not expensive) could bring down Aeroflot. OK, bad example. So much for shoe bombs and hair gell. Who needs it? Bring your blackberry. Mateus

1. Interference. "Does not!" "Does so!" "Does not!" "Does so!" <-- none of that matters. It could under some circumstances, depending on the equipment involved. Rather than try to publish, and enforce, the (possibly) interfering devices from the vulnerable aircraft, all are banned. 2. Distraction. When the flight crew needs your attention, usually below 10,000 feet of altitude, they don't want you watching/listening to something else. 3. Compassion. The sudden increase in workload for coroners at all the major airports could be devastating. They would be busier because that chatterbox moron seated less than an inch from you for the last 4-hours would probably choke to death on that sweet LG-200 suddenly jammed down his throat.

because the cell phone signals interfere with the "Robotic stewardess'". If one is found on their cell phone, the stewardess could malfunction and then what a disaster! No one would get their drinks or food!! Y'all best stay off your cell phones on the airplanes because If americans don't eat, they get angry!!

Interference

It might interfere with the planes electronics.

they say it might interfere with the plane's electronics