GPS on a plane 2: San Francisco - Toronto - Ottawa

I have been interested in small, inexpensive GPS loggers mainly for geocoding photos.
My current fave is the Globalsat DG-100, despite its terrible software.
(It has the SIRFstar III chipset, which is sensitive enough to do this.  SIRFstar II may not be able to, at least I've never been able to get a lock on a plane using my Sony GPS.)

I have been interested to see if I can capture entire plane flights, including geocoding photos that I take in the air.  This is possible.

Please note however:
1) Ask the flight crew for permission (well, at least once per airline, anyway)
2) The logger I use is self-contained.  If you have a Bluetooth logger, or some other kind with some transmission facility, you may not be allowed to use it.  Only a few airlines permit Bluetooth, and I don't think any of them permit it during takeoff and landing

You have to be next to a window, the GPS needs a good sky view.  I usually hold it in my hand about 10-15 cm below and to an angle to the window during takeoff and landing, the rest of the time it can just sit on your seat tray.  You can see examples of the positioning at the bottom of this post.

So, what do you get?

Google Earth can read GPX files directly, this is the result of loading San Francisco to Toronto.
Just to emphasize, this is real data from my GPS.  There's a little leg there on the SF side which is my taxi ride from Mountain View.

If you want to get fancier, GPS Visualizer.com can take GPX files and do all sorts of cool things with them, including colouring by altitude or by speed, as well as making time-based tracks for Google Earth to play.

People often complain about GPS altitude estimation, but it looks fairly reasonable to me, 11000 metres.  The speed estimates on the other hand were way off, it estimated the plane was going like mach 3 if I read the numbers right.

I imagine the relative speed information is correct though.

Here's a view of my Toronto to Ottawa flight coloured by speed

And here's the same flight with Google Earth tilted, with a track produced using GPS Vis setting "Altitude: Absolute (flight)"

How accurate is it?  Well here's me landing in Toronto (cyan line)

And here's what I think is an amazingly cool comparison of a view in Google Earth compared with a photo whose geocoding tells me it was taken in the same spot

Google Earth, with geoposition of photo taken indicated within the screen cap, full photo below.  The zigzag road makes it pretty obvious they are images of the same location, one (probably) satellite, the other taken by me this morning

Positioning of GPS:

I will upload the GPX and KMZ track info later, so you can load the tracks into Google Earth yourself if you want.

Previously:
June 24, 2007  GPS on a plane

Comments

[JohnJohn]

I had a Sony GPS-CS1 and I plan to buy the Globalsat DG-100. Can u say me how much time you can record data with the memory of the Globalsat?

Thanks!

[erictai]

Just came back from a China trip. Flew from Los Angeles to Hong Kong, Hong Kong to Beijing, Beijina to and from Harbin, then Beijing to Urumqi, then Shanghai to Hong Kong, all tracked by GPS units. I have posted the tracks in everytrail.com. Just search China or Hong Kong.
I brought my Globalsat 359 receiver, Holux M-241, Gisteq and my PDA phone AT&T 8525 with GPSTUNER installed. I could never get my GPS fixed when holding them in my hand next to the window, very disappointed, then I discovered that my 359 could fit in between window and window shade with no effort, and my GPSTUNER does the great job, I was so happy!!!I think DG-100 is little too thick for most planes I flew, except Boeing 737 may be.

[Richard Akerman]

I wouldn't recommend placing your GPS directly against the window. If you get a fix on the ground, before takeoff, you should be ok with the GPS sitting on the tray table next to the window. If you wait until the plane is in the air, you may have a hard time getting a fix.

[erictai]

yes, my GPS was fixed before the plane left the gate, then I left it between the window and its shade, thru Bluetooth, I can see the status on my PDA.