Setting correct RTH

[Litchy76]

Recently set RTH with Mavic Air flew briefly until suffering iPad drop out with cpu overloading message - in activating RTH on controller I observed MA RTH at height of 50 metres settling directly over tree tops in line of sight with take off position. I had enough control in between IPad issues to descend avoiding trees but wondered what would have happened if my control did not return. Learning for me has been to check RTH height obstacles and RTH height set. Cheers Litchy76

 

[Deleted member 94047]

RTH altitude should not be something you set once and forget. It should be part of your preflight check. Review and adjust if needed before every flight depending on flight environment and flight characteristics. Having said that, mine is set at 60m and hasn't changed in a while since I fly in an environment where that is high enough to be clear of any possible obstructions.

 

[DanMan32]

MA is supposed to be able to avoid collision during RTH. I wouldn't completely rely on it, but it will help if you misjudged needed height.

Did you mean you ascended to avoid the trees?

 

[Dakarenduro]

There are 3 different RTH scenarios that come into play. All depends what your situation was. See page 13 of your manual-

RTH Procedure
Smart RTH, Low Battery RTH, and Failsafe RTH follow this procedure:
1. The aircraft adjusts its orientation.
2. a. If the aircraft is further than 20 m from the Home Point it ascends to the pre-set RTH attitude and
then flies to the Home Point.
b. If the aircraft is between 5 m and 20 m from the Home Point it flies to the Home Point at the
current altitude, unless the current altitude is less than 2.5 m, in which case the aircraft ascends
to 2.5 m and then flies to the Home Point.
c. If the aircraft is less than 5 m from the Home Point it lands immediately.
3. The aircraft lands and stops its motors once it reaches the Home Point.

 

[Dakarenduro]

Note Failsafe will attempt to follow your actual flight course, retracing the aircraft's flight path. Versus simply going to thr RTH height and going directly to the homepoint.

 

[dawgpilot]

Something to be aware of: with no sensors on the top of the MA, RTH can be a problem if you are under a tree canopy when it activates. Always set your RTH value to account for the local environment.

 

[Litchy76]

RTH altitude should not be something you set once and forget. It should be part of your preflight check. Review and adjust if needed before every flight depending on flight environment and flight characteristics. Having said that, mine is set at 60m and hasn't changed in a while since I fly in an environment where that is high enough to be clear of any possible obstructions.

Thx agree

 

[Litchy76]

MA is supposed to be able to avoid collision during RTH. I wouldn't completely rely on it, but it will help if you misjudged needed height.

Did you mean you ascended to avoid the trees?

Thx no had tried to RTH but was sitting above tree canopy luckily I had control to cancel RTH and manually descend avoiding trees

 

[Litchy76]

Note Failsafe will attempt to follow your actual flight course, retracing the aircraft's flight path. Versus simply going to thr RTH height and going directly to the homepoint.

Ok so this would activate if my IPad ceased working mid flight ?

 

[Litchy76]

There are 3 different RTH scenarios that come into play. All depends what your situation was. See page 13 of your manual-

RTH Procedure
Smart RTH, Low Battery RTH, and Failsafe RTH follow this procedure:
1. The aircraft adjusts its orientation.
2. a. If the aircraft is further than 20 m from the Home Point it ascends to the pre-set RTH attitude and
then flies to the Home Point.
b. If the aircraft is between 5 m and 20 m from the Home Point it flies to the Home Point at the
current altitude, unless the current altitude is less than 2.5 m, in which case the aircraft ascends
to 2.5 m and then flies to the Home Point.
c. If the aircraft is less than 5 m from the Home Point it lands immediately.
3. The aircraft lands and stops its motors once it reaches the Home Point.

Thx for detailed reply

 

[Dan C]

Something to be aware of: with no sensors on the top of the MA, RTH can be a problem if you are under a tree canopy when it activates. Always set your RTH value to account for the local environment.

...and with no sensors on top, it might ascend into trees upon activation of RTH. This is not a win here, I'm afraid.

 

[DanMan32]

Ok so this would activate if my IPad ceased working mid flight ?

Not if only your app failed as your RC will still have control, but yes if your RC fails or AC loses signal from RC.

But perhaps so if flying by Wi-Fi. I can't test that as M2 doesn't have Wi-Fi mode.

 

[BossBob]

Note Failsafe will attempt to follow your actual flight course, retracing the aircraft's flight path. Versus simply going to thr RTH height and going directly to the homepoint.

For those who skim the forums, please note that the Mavic Pro does not attempt to retrace the aircraft’s flight path. If below RTH preset altitude it will climb then return home in a straight line.