I was using the DJI GO APP to review one of my flights.  I notice that on one part of the flight my return speed was 62mph / 100kmh

I'm like damn thats really motoring.  I had been flying into a stiff headwind so was not surprised it would return home faster. However my Healthy Drones only lists 42mph as my max speed recorded.  So that's a 20mph difference. Can DJI explain why the difference?

Perhaps DJI is using ground speed vs airspeed for the Healthydrones?

Presumably the DJI value is in Km/h instead of MPH, even though it is labelled MPH?

How come you are using MPH, FT and degrees F in Taiwan?

Nigel_ Posted at 2017-3-16 01:41
Presumably the DJI value is in Km/h instead of MPH, even though it is labelled MPH?

How come you are using MPH, FT and degrees F in Taiwan?

DJI is in MPH.  You can change on healthy drones and in your app to show imperial or metric. I grew up in imperial before the switch so either is good for me.

"Perhaps DJI is using ground speed vs airspeed for the Healthydrones?"

All the speed numbers come from the same place - the GPS.
GPS only gives speed over the ground, there is no way to get airspeed.

Labroides Posted at 2017-3-16 03:13
"Perhaps DJI is using ground speed vs airspeed for the Healthydrones?"

All the speed numbers come from the same place - the GPS.

OK.  Then there is a discrepancy of 20 mph as I checked log in Phantomhelp and that shows 42mph as well.

blackcrusader Posted at 2017-3-16 04:51
OK.  Then there is a discrepancy of 20 mph as I checked log in Phantomhelp and that shows 42mph as well.

If Phantomhelp shows 42 mph at 10:44, I'd trust that.
You can see the actual data points for every 1/10th of a second.
The Go app has shown a few glitches with metric/imperial mixups.
A speed of 63 mph is a bit hard to believe and you wouldn't get your Phantom back if it really was that strong.

there is a bug in the latest version of DJI Go for Android where it incorrectly shows the speed, its about 20-30mph more than it should be. The version for iOS does not have this, and uploading logs to HealthyDrones will show the proper value. I put up a thread a few weeks ago about this but no-one from DJI responded. You have Android, yes?

digdat Posted at 2017-3-16 05:56
there is a bug in the latest version of DJI Go for Android where it incorrectly shows the speed, its about 20-30mph more than it should be. The version for iOS does not have this, and uploading logs to HealthyDrones will show the proper value. I put up a thread a few weeks ago about this but no-one from DJI responded. You have Android, yes?

Yes I have Android.  I did not see your thread.  Pity.

Thanks for you reply though.  Was hoping DJI reps would also reply on this.

Labroides Posted at 2017-3-16 05:28
If Phantomhelp shows 42 mph at 10:44, I'd trust that.
You can see the actual data points for every 1/10th of a second.
The Go app has shown a few glitches with metric/imperial mixups.

Well it was 62.3mph on the return leg with a strong tailwind.  My initial flight was into a headwind. Best way to fly really so you always have enough to get home easily with a tail wind.

Once I got a RED low battery warning at 52% I flew home at full throttle and got back to home point with 35% battery remaining.  Cruising at a nice speed for sure.

Labroides Posted at 2017-3-16 05:28
If Phantomhelp shows 42 mph at 10:44, I'd trust that.
You can see the actual data points for every 1/10th of a second.
The Go app has shown a few glitches with metric/imperial mixups.

Well damned if I didn't get 52 mph on healthy drones this morning.  I guess sunrise generates some winds