@ aha1973,

"The software could really tell: :the height, the flight sticks, the  bottom sensors can definitively tell if there is a clear intention on  the pilot to land and therefore overrule the decision to trigger the  RTH."

I don't agree with that at all. I regularly try to fly low at two or three feet off the surface, and I have to descend to that point to start. If Spark needed to return home because of a low battery, I'd want it to.

I say that as someone who went through the same experience you did, when the Spark was right in front of me, four feet off the ground. Scared the bejeezuz out of me but I quickly realized what must have happened and cancelled it, and finished landing manually. Now I know, and I keep it in mind when I'm stretching the battery time.

Gunship9 Posted at 2018-10-16 16:12
RTH is surprisingly confusing to cancel.  After taking off with less than a half charged battery, I cancelled RTH twice by making a mistake the first time.  RTH cancel button will ask you if you want to cancel the return to home when you select it.  It gives you the option of okay, or cancel.  Hitting cancel will cancel the cancel of RTH.  You have to hit cancel then okay.  It was confusing in the sunlit screen.  I hear pause button works but haven't used it yet.

I've never used RTH because I don't trust it to fly better than me.

The "cancel" button on the RC stops RTH right away without a pop up in the app.

KlooGee Posted at 2018-10-17 11:53
Lol!  If you think 1.5x is entertaining, you should go for the full 2x!

I did come across your videos but I have not had time to take a look.

I got an update from Support.

The Home Point is recorded as soon as the GPS signal strength reaches level 4.  This fact is certainly not stated anywhere on the user manual, and I do believe is a relevant fact. This obviously implies that the Home Point can be recorded in-flight. As it's the first time that I come across this issue, I would be interested to know if the DJI app makes any audible alert advising that the home point has been recorded.

Hi Alex, sorry for teh crash accident, I managed to get your case number via your Forum account and upon the data analayis, the accident was caused by pilot error:
1. The aircraft worked in GPS mode, and responded to RC command well;
2. T=808.2 s, H=-0.4 m, D=28.2 m, battery 19%, RTH was triggered due to Low Battery; the pre-set return height was 30 m, then the aircraft began to ascend;
3. T=815 s, H=6.3 m, D=27.9 m, the aircraft crashed when it was ascending; The aircraft could not avoid obstacles above it. Please fly with caution.
Conclusion:
Pilot fault. No warranty.

Is it the same case that you are talking about? Home Point recording will need strong GPS signal, when taking off, we can wait the Aircraft Indicator blinks green which means the Home Point is recorded, we can also see a green point in the map. The drone crashed during ascending, it is pilot error, please let us know if you have further concern.

DJI Mindy Posted at 2018-10-30 04:15
Hi Alex, sorry for teh crash accident, I managed to get your case number via your Forum account and upon the data analayis, the accident was caused by pilot error:
1. The aircraft worked in GPS mode, and responded to RC command well;
2. T=808.2 s, H=-0.4 m, D=28.2 m, battery 19%, RTH was triggered due to Low Battery; the pre-set return height was 30 m, then the aircraft began to ascend;

Mindy,

The aircraft triggered the RTH based on wrong parameters, thus the aircraft eventually crashed:

1. Automatic Takeoff: Does the application prevent the takeoff if the GPS signal is not strong enough?
2. Home Point: The Home Point was recorded after takeoff, where as the documentation, at least in Spanish, states that if the GPS signal was strong enough prior to take off the HP will be the location where the aircraft took off. What it does not state is that once the GPS signal reaches the fourth bar the GPS  the HP will be recorded. I still cannot understand what sense it makes to record an HP in flight.
3. The RTH is triggered base on altitude and distance from HP. The altitude was almost 0 and the distance to the HP was triggered inaccurately, as the distance was recorded in flight.
4. Pre-Flight checks mentioned in the official documentation are not documented either.

aha1973 Posted at 2018-10-30 05:44
Mindy,

The aircraft triggered the RTH based on wrong parameters, thus the aircraft eventually crashed:

When we power on the drone, if the GPS signal is strong, the Home Point will be recorded. If the GPS signal is not strong, we can still take off, but it will record the Home Point when the GPS signal is strong enough during the flight, you can check the flight record when and where the Home Point was recorded.
Per your data, the drone worked in GPS mode and responded to RC command well. The RTH was triggered because of the low battery, according to the RTH procedure, when the current altitude is lower than the pre-set return height, it will ascend to the pre-set altitude and then return to home. The height was -0.4 m when the RTH was triggered, it crashed when it was ascending, it is clearly pilot error, please check more details of the RTH procedure, thank you.

Mindy

"When we power on the drone, if the GPS signal is strong, the Home Point will be recorded. If the GPS signal is not strong, we can still take off, but it will record the Home Point when the GPS signal is strong enough during the flight, you can check the flight record when and where the Home Point was recorded."

¿Can you please let me know where is this stated in the documentation in Spanish (by the way that is the Mavic air which is twice the price and with certainly more sensors)? ¿Can someone explain what is the logic behind recording a home point in flight?

If the home Point would have not been recorded in flight, (again not documented) the distance would have fallen below the 20 meters and the aircraft would not have flown to the pre-set altitude and should have only risen to 2.5 m.

With regards the RTH cancellation it's clear that next time I will fly with headsets as you might expect, I was looking at the drone trying to land it, thus I did not recall the RTH alert was triggered.

aha1973 Posted at 2018-10-30 22:51
Mindy

"When we power on the drone, if the GPS signal is strong, the Home Point will be recorded. If the GPS signal is not strong, we can still take off, but it will record the Home Point when the GPS signal is strong enough during the flight, you can check the flight record when and where the Home Point was recorded."

Hi Alex, can you please sync your flight records to the server and PM me your DJI Account, I would like to check your flight records about the Home Point, thank you.