Ask the Captain: A reader challenges in-flight electronics rules

ByABC News
October 3, 2011, 2:53 PM

— -- Question: Hello Captain Cox. I've read your past columns regarding the use of electronic devices. I would like to share with you some observations I have made while flying and get your input.

1) Regarding the use of electronic book readers: Most of the devices that I use such as a Kindle and iPad have their wireless capability disabled. I would challenge your assertion that they have the capability to interfere with in flight instrumentation. The available studies I have been able to find on the Internet show that the EMF emissions on these devices is very low. Lower in fact than the typical EMF emissions of the incandescent light bulbs used in the reading lights on airplanes.

2) As far as the devices with wireless turned on, a congressional study a few years ago sought to determine if these types of devices were a threat to commercial aviation. They were unable to find any verifiable incident where a wireless device (cellphone, etc.) had interfered with the instrumentation on a commercial aircraft. There was one anecdotal report of pilots reporting interference with their instruments. After that plane landed, it was discovered that there was a laptop in a passenger's in-cabin luggage that was turned on with its wireless capability enabled. Boeing subsequently purchased the laptop from the passenger and was unable to recreate the interference with instrumentation using the purchased laptop in a controlled setting.

3) I recently had the opportunity to sit next to an American MD-80 pilot (whom I discovered had been two classes ahead of me at the Air Force Academy). When we started discussing the subject of interference from in-flight usage of wireless devices, he expressed to me that there was no way they could interfere with modern instrumentation used in today's aircraft.

4) I have observed on the American flights with Wi-Fi available that the GoGo inflight wireless access points are enabled throughout the flight. From the moment the aircraft is started at the gate all the way through landing and taxiing to the gate, these wireless access points are continuously operating and emitting their wireless signals. This would seem to contradict the assertion that this type of RF transmission could interfere with in-flight instrumentation.

5) If these types of emissions are so harmful to sensitive flight instruments, then why are the general public allowed to hold them right next to their skulls near their brain for extended periods of time?

6) If the instrumentation on an aircraft is so sensitive to emissions from a low power emissions source like a cellphone or laptop that it could potentially interfere with their operation, wouldn't it be subject to much stronger sources of EMF interference like a lightning strike?

7) FAA studies have shown that the average aircraft takes off with a minimum of 4 cellphones on every flight. If this is the case then why have we not seen any reports of airplane crashes or other types of incidents attributed to interference from an enabled wireless device onboard?

-- submitted by reader Kelly Clark