Originally Posted by
SJCFlyerLG
There is only anecdotal evidence connecting the use of low-power wireless devices to abnormalities in aviation instrumentation. There is no proof either way - hence, the ban. Pilots that observe avionics abnormalities might assume it is due to phone usage, but again, there is no definitive proof. However, since it is a rule, and it is not hard to follow..
I've posted on this subject before (as have others). There are two reasons why this ban is in effect:
1. GTE, who sells and receives a lot of monopolistic revenue from the armrest Airphones, was concerned that cell phones would put them out of business. So, in the late 1980s or early 1990s, they convinced the FAA to conduct a study concerning possible interference from cellphones. As you might expect, the study was hardly independent. The study didn't conclude that there would or would not be interference. It said there was a "possibility" of interference. The possibility required several low-probability conditions to exist simultaneously. Since the study did not rule out interference 100% of the time, the FAA banned in-flight use of cellphones "out of an abundance of caution." GTE orchestrated the study and won.
2. The cell phone companies didn't really object because they would have had to invest a large amount of capital in the technology necessary to ensure a high probability of maintaining a connection at 35,000' moving at 650 mph. Among other things, they would have had to redesign cell towers to permit the signal to point up. Just think about how hard it is to maintain a connection moving at 60 mph on Planet Earth.
The technical issues associated with cell phone frequency interference with modern commercial airliner navigation and flight control systems don't pass the giggle test. But, there were other, more powerful, forces at play when the FAA made this determination.