GPS on Commercial flights?

[Ringway Flyer]

Just returned from Mallorca with 'er indoors, and after several 'where are we now?' questions, which were difficult owing to intermittent cloud cover, I wondered why I'd not brought my hand held GPS... Are there any restrictions on using one? Do different airlines have different policies? Is an active antenna needed to get a result? (I suppose it will depend on which way the aircraft is going?)
Just curious...

[Sunfish]

You might get classed as a terrorist:- "Vey do you vant to know vere ze aircraft is? Ve haf pilots to do that"

[None]

From my Ops Manual:


GPS receivers utilizing external wires (i.e. suction cups) may be operated only:

1) when the boarding door is open
2) during extended taxi delay after an announcement allowing PED use is made
3) during taxi-in

GPS receivers that do not utilize external wires may be operated at all times.

[alexban]

The GPS's may not work inside the plane.You must have an 'clear sky'in order to get satelite reception.The small window from the pax is not enaugh. The windows from the cockpit have metal shielding (for antiice) and you won't get any reception either. I've tried my magellan GPS, no result.
I've used it on older planes,but it was a different type of windows on the cockpit.

[Pilot16]

As far as my understanding of electronics go, a GPS receiver only receives sattelite signals. That is to say, nothing is transmitted from the device to interfere with the aircraft systems.

The unit is merely picking up the signals that are already there in the atmosphere, if something like this were to interefere with a/c systems, then it would have done regardless of a GPS receiver switched on or not! :}

[jezbowman]

Depends how you look at it. Many microprocessor devices that tune to radio signals will be using a PLL (phase locked loop) which will include genetating a signal within the unit equal to that frequency which it's trying to recieve. In normal circumstances this would be fine, but since the unit isn't FAA/CAA approved there are no gurantees that the unit may not malfunction and begin transmitting energy on these frequencies. That would be bad, especially if the a/c was actually using GPS to navigate as the signal may be lost.

Same reason why you shouldn't use a handheld AirBand reciever, FM reciever or as the offical line goes - "any device capable of transmitting or recieving radio frequencies".

My mate was once asked to turn his GPS reciever off on a trans-atlantic. He was told it could interfer with the planes systems. And YES it could, but (arguably) so could a CD player with enough malfunctions.

[oscarmike]

Interesting. I posted a message on this very subject on the Passengers / SLF board back in April this year. I've been trying to find a way to post a link to the thread, but haven't succeeded - if you want to look at it, just do a search on "Use of hand-held GPS" on the Passengers / SLF board.

Anyway, in essence, what I said was that I regularly used to carry a small hand held GPS unit on commercial flights. It was a simple Magellan Sport Trak unit, which had a very rudimentary moving map.

For it to work, it was necessary to hold it quote close to a cabin window to enable it to "see" the satellites, as it had no external antenna, and no provision for attaching one.

It was then possible to monitor our position, ground speed, heading, and if our destination (or somewhere close to it) was in the internal database, it would also calculate our ETA.

As a PPL (A) this was all interesting stuff, and also answered the inevitable "where are we" questions from my travelling companions.

On one occasion, a member of cabin crew spotted it and asked what it was. I explained that it was a GPS receiver, and as the lady's husband was a PPL also, she was familiar with the device, and quite happy for me to use it on board.

However, on another occasion, we were coming back from Spain on an ****jet flight, and a member of cabin crew spotted it and asked what it was. Again, I explained that it was a GPS receiver. She then told me (in no uncertain terms) to switch it off immediately, and that devices like that were strictly prohibited on board.

Replies to my posting on the other bulletin board varied from the highly technical (most agreed that whilst in essence, as it was a receiver, it could not interfere with the aircraft systems) to the downright insulting, where I was accused of being an anorak and likened to spotters.

However, it is most interesting to get a definitive answer from None's Op's Manual.

Regards

OM

[BOAC]

Here it is, OM (http://www.pprune.org/forums/showthread.php?s=&threadid=127187)

[Deaf]

Anything with EMC is an open question, to take a recent example :

http://www.atsb.gov.au/aviation/occurs/occurs_detail.cfm?ID=660

http://www.pprune.org/forums/showthread.php?s=&threadid=143311

[Ringway Flyer]

Very interesting.... I used my Garmin GPS12 for several years in a PA28, and very useful it was. The machine we now use has Garmin radio/GPSs fitted, so the hand held one stays at home. I also have an amateur radio licence, so appreciate the comments about spurious signals being radiated - my pc flattens parts of the HF spectrum - so perhaps an A5 sized atlas and a bit of research before hand might make the journey more interesting! Dare I use my calculator to help with the maths?? Thanks for all your comments....

[Gerard123]

When I got my new toy, a Garmin Pilot 3, I couldn't help using it while sitting in the back. I got perfect reception (3d NAV) the whole flight. The weather was about 5/8 cloud. The only person who checked on me was a rather nice girl sitting next to me,who was most impressed with me being a pilot ;)