Don't know what happened, it didn't post my text first time around.  anyway my question was..........       When the RTH altitude is set, say at 150'.  Is that 150' relative to initial launch?  Or is that a GPS altitude?  Here in south central Pa. with rolling hills, will the drone fly up and down or stay at one plane across the uneven terrain?

P3S does not follow terrain contours during RTH. It takes the straightest route back at the preset RTH altitude based on the altitude sensed when the home point was set as being 0.   Got tall trees and hills in the way, set the RTH altitude accordingly.

That is 150' above your home-position, so you should set it to clear any obstacles that it may encounter on the return journey. If your ac has object avoidance it will automatically avoid objects on the way back, but trees, especially in winter, are unreliable.

Dockater Posted at 2017-12-18 08:10
That is 150' above your home-position, so you should set it to clear any obstacles that it may encounter on the return journey. If your ac has object avoidance it will automatically avoid objects on the way back, but trees, especially in winter, are unreliable.

Gotcha       Thanks for the info      probably just saved a tree   

The P3S doesn't have obstacle avoidance.  Better set the RTH height higher any tall things where you're flying.

^^^ yep, always set it a bit higher than the tallest object within the immediate area I'm flying in for safe measures.

ALABAMA Posted at 2017-12-18 08:38
The P3S doesn't have obstacle avoidance.  Better set the RTH height higher any tall things where you're flying.

You mean higher than ALABAMA          see you in Atlanta         GO DAWGS !!!!

WAR EAGLE......Already hurt me enough lol

Hi there, the RTH altitude is the relative altitude above the home point. It will be better to set higher RTH height than the tallest object. Feel free to contact us if you have more questions.

If you want to know how much altitude should has been to set then you can make it so. Take off,let the cam looks straight to the front of the copter to the direction of the highest point you can see on your flight area. Ascent the altitude of the copter so high that the highest point  is visible in the lowest 1/10th and add 15 meters to the showed altitude on display.
Example: I got an unknown terrain and look around for many trees and let the P3 takes off. I look on the display and read 45 meters then the RTH altitude will be 55 - 60 meters. So i´m on the safe side if the copter kicks the RTH in and come back.

what Susan said