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Does anybody know if there is a GPS signal available on board of a plane with a common and normal GPS receiver?

11 Answers 11

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Unfortunately the plane body does an excellent job of blocking GPS signal. In general if you're in a window seat you will be able to get a signal by holding the GPS near the window (or, for example, on a tray table) - but if you're elsewhere on the plane it's very unlikely you'll get a signal.

The exception to this may be the new Boeing 787, which is made primarily of Carbon-fiber reinforced polymer (CFRP). Not only does CFRP allow for larger windows (which would allow a greater visibility of the sky, and thus more GPS satellites), but it's likely that the GPS signal would pass through the aircraft shell better than on conventional planes.

Keep in mind that not all airlines allow passengers to use GPS receivers in flight (they are technically "radio receivers" which are often not allowed). Be sure to check with the specific airline and/or the flight crew to confirm that you are allowed use one.

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    Do you know if the speed of the plane can disrupt the GPS receiver? – Ricardo Giaviti Mar 13 '14 at 19:17
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    I've seen my GPS report a speed of 1258km/hour when travelling with a ~300km/hour tailwind. The "airshow" display on the plane showed a speed 2 km/hour different, so the GPS was obviously extremely accurate even at that speed. (Yes, that's technically faster than the speed of sound - but due to the tailwind we were not technically going faster than sound relative to the air around us) – Doc Mar 13 '14 at 21:07
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    @RicardoGiaviti: planes internal systems also use GPS. So do some missiles guidance systems. And these fly way faster than any plane. – vartec Apr 23 '15 at 19:01
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    Munitions restrictions in the US mean most consumer GPS would fail to operate if both alt>18000m and speed>515m/s. You shouldn't be near either limit in commercial aircraft. Hiking units use the same chipset as others and wouldn't be expected to have any problems at airline speeds. – BowlOfRed Apr 24 '15 at 16:48
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    But see this answer reporting that the 787 had the worst GPS experience. – phoog Jul 4 '16 at 18:59
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Yes, but the signal can be a bit weak. It's best to hold it to the window to get a lock. Depending on the GPS device, some are able to "hold onto the lock" even if they are not facing the window, so you only need to have it by the window for the initial lock. You may or may not be allowed to have it in the GPS.

Here's my GPS while I was travelling near the equator. Look how I'm 4,500 m above sea level and travelling at 600 km/hr.

near the equator, 4.5 km up and moving at 600 km/hr

crimey was that 4 years ago... where does the time go...

  • Crimey? I assume crikey or blimey? – Martin Smith Sep 3 '17 at 20:42
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I am a (private) pilot, and have used my various GPS enabled devices for years both when I fly myself, as well as on commercial flights. (In the past, when they were not allowed, I applied for and obtained special permission from the airlines I was then flying.)

Depending on the seat location, and position of the GPS satelite constellation, my reception varies from mediocre to excellent. With a newer iPad, possibly containing a better chip or antenna, my capture rate for good position is generally over 90%, with the proviso that a window seat be selected.

Aircraft type seemed unimportant - until my most recent commercial flight. On the outbound leg, over 10 hours on a B777, I enjoyed superb capture and positional accuracy. The return leg was on a B787, and over the more than 10 hours of flight time I received not a single fix, even with the iPad up against the (large) window. Indeed, I wonder if the 787 has some kind of GPS jammer in the cabin, since the GPS signal actually occasionally showed 1 meter accuracy, but without an actual location, and then immediately dropped to "No Fix" - so it seemed that an extraneous signal might have been present.

BTW it is worth noting that a number of highly experienced pilots have recently landed at incorrect airports, with several such events well publicized. An iPad in the cockpit, running one of the readily available aviation programs, would have avoided such embarassing - and potentially dangerous - events.

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    Wait, are you claiming that iPad GPS and apps are better than what is installed by default in the airplanes...? That sounds scary – bjorn Jan 7 at 14:55
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Yes, I did have GPS reception on my cellphone during a flight. However, it took quite a long time to get the initial coordinates, and I could not get updates on my location very often (the coordinates changed maybe once every 3-5 minutes). So I would say you would have bad reception in the best case.

Maybe dedicated GPS devices would have a better antenna & reception than my $300 phone.

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I have flown (as a pilot as well as a passenger) with a variety of GPS units (hand-held Garmins, iPhones, iPads), in a variety of aircraft, from my own single engine plane up to the largest commercial, with the portable GPS unit providing excellent position, speed and altitude information. Indeed, my iPad correlates superbly with my Garmin GNS 530, and serves as a backup for the (certified) Garmin unit.

Several mis-statements are common:

  • an iPad and iPhone can (and most do) contain a 'real' GPS unit. Some information can be obtained by triangulating cell phone towers, but cell reception can be turned off, or the unit can be in the middle of a cell-free zone (such as an ocean) and GPS service continues.
  • an iPad of iPhone, with the cell system configured to 'off', will not interfere with aviation electronics. In that configuration, the unit is in 'receiver mode' only. However, please do turn the cell phone portion of the unit off!
  • The fuselage of most commercial aircraft will allow sufficient penetration of the satellite-transmitted GPS signal to permit excellent accuracy. I have flown extensively while receiving good signals - in a large variety of aircraft, including regional jets, B737, B757, B777, MD80 etc etc.
  • I have only flown in a B787 twice - and in NEITHER CASE WAS I ABLE TO RECEIVE A USABLE GPS SIGNAL. I had a window seat both times, each flight was in excess of 10 hours, and at no point did I receive even a marginally usable signal. I presume the fuselage of the B787 contains denser EM shielding than the typical aluminum skinned airplane - probably related to lightning protection requirements for the nonmetallic structure.
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    Hello, welcome. Do you need to shout? Also, I don't think you need to mention cellular receiver, while it is used on earth for positioning, it seems clear for this question that it is off-topic. – Vince Apr 23 '15 at 17:46
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    @Vince New users may not be familiar with the editor. The best thing to do in these circumstances is to simply fix the formatting of the post, and perhaps point them to the online help for same. – Michael Hampton Apr 23 '15 at 17:58
  • I concur with your observation on the Boeing 787. Not only was it impossible to receive GPS right up against the window, I could not even receive cellular signal inside the plane at an airport. In other airplanes, my phone works just fine. – Nayuki Dec 29 '16 at 2:00
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I tested this once on a flight which claimed it was fine, once you'd taken off, and not during landing - to use devices like this.

I have an app on my phone (MyTracks) which is meant to track you when running, for example, but I just turned it on and left the phone running in my pocket. Not ideal for GPS, but I was in a window seat, giving it a slight chance.

Long story short, there were some data points recorded during the flight, and at a range of altitudes. It wasn't a steady connection, but it was certainly received intermittently, until the final 'please turn off all electronic devices' warning came and I had to stop the test.

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I have a Garmin Oregon 550 and I can confirm that one can get a decent signal if the reciever is positioned close to a window. Getting the initial fix might take a few minutes, however. For all the flights where I did not have a window seat, I lost the signal sooner or later and never got a fix again.

My experience is, that different airplanes actually do make a difference. I remember having excellent signal in a Boeing 747 Jumbo, while in Airbus A340 the GPS reciever would have to be close to the window all the time to prevent it from loosing the signal. I can also confirm from a recent flight that in the Boeing 787 Dreamliner there is absolutely no signal at all, not even close to the doors or emergency exit. I didn't expect this at all due to the plane being made of carbon fibre which normally transmits the GPS signal. I figure that at least the windows are (electrochromic) smart glass windows and they therfore don't transmit any GPS signal. So holding the GPS device close to the windows doesn't help in a 787.

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The best GPS performance I ever got on a plane was on an iPhone 5s, by:

  • getting a window seat on the side that will face the equator during the flight
  • getting a good starting fix before the plane starts moving
  • putting the phone flat against the window and pulling the shade down to hold it there.

My Garmin eTrex-30 claims to get 3-5 meter accuracy when held against the window, but drops to ten meters in my lap (and frequently claims to have lost signal). Also, I don't trust its accuracy claims because once out in the open, it mapped two fixes twelve meters apart when both were actually taken at the same spot and it claimed four meter accuracy.

  • It'd be interesting to see whether you could get the same performance on a north-facing window. It shouldn't really matter, since GPS satellites are not in equatorial orbits like, say, satellites carrying TV signals. – Michael Seifert Jan 24 '17 at 15:19
  • Ohs, I thought they were geosynchronous. – WGroleau Jan 24 '17 at 16:05
  • It's true that the satellites are not in geosync orbits; they follow the usual "apparent sine wave" pattern, but that pattern does "cycle" back and forth with the equator in the middle. So if you look at the "satellite map" that most GPS receivers and apps can display you'll find more of them closer to the equator than farther away. My experience using GPS aboard commercial a/c (mostly with Garmin GPS V, then later, bluetooth receivers with SirfSTAR III chipset) has invariably been that my receiver can "see" far more sats from an equator-facing window than from the other side of the cabin. – Jamie Hanrahan Sep 3 '17 at 17:24
  • Re my prev cmt - Since your airplane may be south of the equator I suggest that "a window facing toward the equator" is a more generally useful phrasing than "facing south". Edited answer accordingly. – Jamie Hanrahan Sep 3 '17 at 17:27
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I just used my Android phone GPS app to clock the plane's touchdown speed yesterday. The plane was an Airbus A320 , I was seated at the window. The plane's touchdown speed was about 250km/h. It was not easy to clock the speed at landing using an android app because the pilot seemed to apply brake at the same moment of touchdown causing a steep velocity change within subsecond interval. The Android app GPS status refreshes only once per second. But, tracking the flight's location was very accurate. I saw the shore line of Detroit dotted with 2-3 nuclear plant cooling towers, and surely enough the Google map pointed my location at the Lake Huron shore.

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As others have already said, it works in most airplanes, but in the dreamliner specifically (787), it will not work due to the fancy windows that can dim themselves but also contain a conductive material that prevents the GPS signals from getting in. It's not GPS jamming, but just unfortunate GPS shielding. Source: I use my Garmin GPSes in all airplanes I've taken, they've always worked next to the window, except in all dreamliners I've flown in.

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Used galaxy A5 with google map and FLIGHT MAP free inside A320 NEO and Boeing 737-800 with excellent Gps fix (on window seat)for a complete 3 hour flight without any problem.Just turn on gps asap once inside plane or do it even before before bording the aircraft and put phone on flight mode.

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