Technically, there's no problem -- you can almost always see enough satellites through the cabin window to get a good lock. I've done it many times. They don't always work from the flight deck, I understand, due to extra shielding in the glass at the front to protect pilots from radiation.
Legally is another matter. Strictly speaking, as they're radio receivers they're banned by most authorities. Some ban everything anyway (thanks, IAA). I ask the cabin crew whether I'm allowed, and if they're unsure I ask them to take the GPS up to the flight deck when convenient and get a pronouncement.
We had someone on our flight to Malaga a few days ago who was using one. The cabin crew noticed it and brought it up front. We agreed that it couldn't really do any harm as it doesn't transmit and thus won't be expected to interfere any more than a discman or walkman would. However, we also agreed that the guy should've asked us before using it. We called him up front and in the end gave him a jumpseat ride for the descent&approach. So there may be a good reason to take it anyway!
Werl... nearly all radio receivers radiate something as part of their normal operation, and the ones in GPS receivers certainly will. They generate one or more small internal radio signals to mix with the signals they're receiving, and the generated signals can leak out. It is conceivable that if that leakage is in the wrong place at the wrong time, it'll mask some external signal and prevent some avionics from functioning correctly.
That risk is quite high for FM broadcast receivers, which tend to be cheaply made, badly screened and have an internal oscillator that may well work directly in the VHF comms/VOR band. It's quite low for GPSs: I've checked my Garmin 12XL for radioactive incontinence and it's got a clean bill of health as far as I can tell. But there's anecdotal evidence for other GPSs in cars blocking reception of FM radio broadcasts, and there's always the small chance that a fault in the GPS will change its normal mode of working for the worse.
I reckon the risk is minimal, and while I understand the reasons for the blanket ban I'm happy asking for permission and blithely transferring responsibility to 'em as is paid for it
Thanks for all the replies, gentlemen.I think that I will take the GPS and follow the advice, i.e ask permission of the crew on the day.Appreciate everyone taking the time to reply.A last favour, does this routing sound accurate for a flight from EGGW-LEMG. HEN-CPT-SAM-ORTAC-GUR-ARE-POMTA-NOVAN-KABIG- PATEL-SNR-RATAS-ORBIS-TLD-MONTO-CRISA-VULPE-MAR. This so I can preprogam the thing.Thanks
Yes that route is correct however if you are flying on an A320 out of Luton the answer will be no. My airline has issued a notice to all pilots saying that a handheld GPS is not allowed to be used during any part of the flight.
Thanks for that info Flex.I am flying with Britannia tommorow afternoon, and on reading your reply have decided not to bother taking the GPS. I should have checked all this out before buying the thing.If your airline has banned them,then it means there must be a safety aspect,and I am the last person to want to cause any problems.Thanks everyone once again.
FAA have approved the GPS being used by pax as long as it has an FCC endorsement. This after several industry and government studies. Odd that individual airlines in the UK have decided against allowing them. This is uninformed over-reaction.They could foster some good PR by thinking this through a bit more.
Oh well. Anyone is welcome to use their GPS on my machine any time. (Airbus)
From what I read - the more modern the plane, the safer it is from these various devices. Most at risk have been the classics.
A few years ago we got a B-727-200 to add to our two 727-100s. When we recieved the 200 it had no long range nav. of any kind. A bunch of us had boats, one of the guys took his hand held GPS that he had on his boat and started using it on the 200. I flew with him a few times and we used it to see how it worked in a fast airplane. It worked really good. We did NOT tell ATC that we had long range nav., but when ATC gave us a heading for a fix down the road we would use it as a back-up. It was also handy for flight planning.
One of the humorous aspects of this GPS was that because it was made for a boat the winds read out as current. Current is 270 degrees at 97kts. Anyway it worked and there was no interference with anything in the cockpit that we could tell.
Quite a few people on the RAF C130 fleet use their own Garmins etc all the time. We are, of course, in the unique position of having hardly anything electronic on our flightdecks for the things to interfere with except, maybe, the navigator's pacemaker...
It really is quite surprising that GPS (ARINC approved) is not used more by air carriers in the USA and Europe, except perhaps for the COST. Accuracy is dead-on and there are over 11,000 GPS approaches in present use in the USA with many more to come. The wave of the future, except perhaps for CAT II/III.