Welcome to Gadling’s feature, Plane Answers, where our resident airline pilot, Kent Wien, answers your questions about everything from takeoff to touchdown and beyond. Have a question of your own? Ask away!
Bud vents a little frustration:
There is no data whatsoever that cell phones interfere with airplane navigation systems. In fact, there have been tests with cell phone signals amplified ten fold and without interference. So every time the flight attendent comes on the intercom and tells the cabin to turn off cell phones because “they may interfere” with the airplanes navigation system, I simply stop and think to myself, that if they would lie to me about something that doesn’t hurt at all, how much can they be trusted to tell me the truth about something that really might be harmful. I think that if you will lie about a small thing, you will lie about a big one. And since the Captain allows the lie to be broadcast, who can you really trust? Reminds me of the government agent arriving on a doorstep and saying “trust me, I’m here to help you!” Yeah! Right?
I don’t agree with your logic, Bud. The most frequently quoted study was done by Carnigie Mellon University in 2003. Their comprehensive findings were summarized as follows:
The key conclusions were that (1) onboard cellular telephone calls were observed in-flight and activity is appreciable; (2) signal activity was observed in the aviation critical frequency bands at field strengths capable of causing interference to onboard avionics; and (3) onboard spectral activity was observed at flight critical phases.
The entire report is fascinating, but if you don’t have the time to read it all, here is a short interview with Bill Strauss, the person responsible for the report. He found that 1/3 of the time cell phones were being used illegally inflight, their frequencies actually crossed into the GPS band.
The FAA mandates in FAR 91.21 that carriers restrict the use of non-approved electronics devices. Flight attendants are required to enforce these regulations, and even the inflight announcements restricting cell phone use made by the cabin crew must be signed off by the FAA. So, instead of lying to you, these flight attendants are complying with the regulations of their job.
To borrow your logic a bit, let’s imagine a flight attendant who skipped the cell phone announcement. What other parts of their job might they be neglecting? Can you then trust them to check their fire extinguisher, oxygen and escape slide pressures before departure?
It’s been the policy of each of the airlines I’ve worked for that pilots and flight attendants are to be truthful with passengers.
It doesn’t matter what the delay is, we will always try to give as much insight as possible into the reason. There’s honestly no incentive for us to tell passengers anything other than the truth.
The airline I currently work for decided to go through the long and costly process to demonstrate to the FAA that cell phone use after landing and while taxiing to the gate was safe.
The test involved filling every seat with a person using a cell phone from a variety of manufacturers on each of the airplanes the airline operated.
Little regard was given to GPS and ground-based navigation interference, since the airplane was simply taxiing to the gate. Subsequently, each airplane type at the company passed, except for one. When this airplane, an Airbus, was tested, for some reason the smoke detector in a lavatory would activate.
After further modifications, the FAA approved cell phone use while taxiing in for each one of our aircraft types. I realize this is anecdotal, but it does represent at least some sort of interference, I suppose.
In the past, the FCC banned cell phones inflight because they would interfere with the networks on the ground. According to the author of the Carnegie Mellon study:
The FCC feels it can probably lift the ban, even if there are problems of interference [on board airplanes]. They’re saying to FAA, “If you want a ban, that’s your territory.”
Europe has recently approved cell phone use inflight, but that’s still subject to the European Aviation Safety Agency determining that interference isn’t an issue. I suppose in the U.S. if the public demands the use of cell phones on an airplane (a big if) then it’s going to be up to the airlines to convince the FAA it’s safe.
But please don’t blame the pilots or the flight attendants for following the regulations that are currently in place.
Do you have a question about something related to the pointy end of an airplane? Ask Kent and maybe he’ll use it for next Friday’s Plane Answers feature.