According to FAA regulations, the pilot is the final authority on which electronic devices can be used in flight. So I would say that the pilot is EXACTLY the right person to ask.

On CO and UA (and most other airlines I would guess) permissible electronic devices are listed in the inflight magazine/brochure and these both explicitly say that GPS is permissable above 10,000 feet. I've turned on my Garmin GPS during flight and it's lots of fun (for me) to look out the window and know what town/river/street you are crossing over. The FA came over and I showed her the device listed in the magazine. She said that she never knew that.

Did you ever use your GPS during flight?
 

I haven't seen this addressed anywhere else so I'll ask it here. Quick poll: Did you ever use your GPS during a flight?

It was great fun to turn on my Garmin during a recent flight from IAD to EWR. Although I've lived near DC for over 30 years, I am not the best at recognizing landmarks seen through the window during flight. It was great sport zooming down to the street level and zooming out to see exactly our location and speed throughout the flight.

By the way, the inflight magazine specifically permits GPS devices to be used above 10,000 feet. I'm not sure why they don't want you to use it during takeoff or landing.

Hmm, that sounds like fun - especially here in LAS, where wind changes dictate that planes can land in any of the four directions the runways point. Maybe I'll try it next time.

Tried it about 10 years ago with a Garmin GPS III, was interesting to see that the map display speed was accurate at 565 mph and 37,000 ft altitude. Never tried it with my TomTom that I use all over the world as it might be recomputing the roads constantly and freak the damn thing out! It gets freaked out in Stuttgart enough times at the moment!

I had an old Garmin GPS12(?) that I would put in the window and connect to my laptop and track our flightpath, just for fun. This was pre-9/11, though.

Since this is not entirely a UA-related issue, I am moving this to TravelBuzz!

iluv2fly
Moderator, UA

I use my GPS logger all the time.

To my knowledge the use of GPS aboard UA within North America is not really tolerated, so the logger is a great tool as you get all the data onto the computer on demand. And because it is just button size, no one really bothers about it :o ...

I forgot to turn my Garmin Runner 301 GPS off last year after jogging in Hyde Park in London.

I had the GPS in my carry-on luggage on a UA flight from LHR to IAD. After I returned home and plug the GPS into my PC, I was surprised to see I had jogged from London to Scotland....

I did not know why the GPS did not pick anything up after the plane passed over Scotland.

About whether a given device is allowed, yes. About whether it a poses a risk to avionics systems, no.

Pilots know about airways and missed approaches and altitude hold and crosswind landings.

They do NOT know about sideband and parasitic and coincident harmonic emissions. Even if a spurious signal can't get into the ARINC boxes through the shielding, it certainly can enter the system through the antenna.

Aircraft act strangely for unknown reasons all the time. And blackouts of the "glass cockpit" are well documented. Airplanes are ultimately flown by computers, and computers are software, and software has bugs, as well as susceptibility to RFI. It's in the nature of things.

I think allowing electronics in the cabin is a time bomb. We just don't know when the detonator is set for.

On some other air travel related boards there are constant arguments over whether it is legal or within an airline's policy for a passenger to use a GPS during a flight. The arguments seem to center on whether it interferes with onboard avionics. I have never understood this argument as a GPS unit is entirely passive as far as I know. Now I have never broken out my spectrum analyzer to check one, but I cannot imagine what emissions would emanate from a GPS device. Can anyone enlighten me concerning this?

I think all-glass-cockpit aircraft, particularly those that are aerodynamically unstable and uncontrollable in the absence of fine-grain computer control, are a ticking time bomb. I'm not sure that personal electronics in the cabin shorten the timer on that time bomb any more than RFI from other systems on the aircraft, RFI from other aircraft or the ground, or cosmic rays.

But then again, mechanical and hydraulic systems have histories of failures too.

Related discussion may be found here: http://flyertalk.com/forum/showthread.php?t=840979

I did and got a strong response from my old unit ... but it was from the Bluetooth interface which could not be turned off :p .

Now I have a pure USB version of the logger and the antenna is very quiet. The antenna - at the noise cutoff for the analyzer - seems to mildly amplify the 'natural' GPS signal. But we talk <20% of the radiation, the plane is immersed into anyway.

The restrictions on GPS are mere policy, I reckon, originating from the original fear - which is not unreasonable - that antenna circuitry when failing might emit a relatively broad spectrum of radar frequencies. Aerials can be built failsafe - in the sense that they go quiet when malfunctioning - but I doubt that this is a design target of most cheap units.

Anyone know in the iPhone 3G whether it can receive a GPS signal while in airplane mode, although I guess it would be hard to download the maps with no data connection too?