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RTH query.

David Smith

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Hi All. Just returned from the highlands of Scotland. We walked up a few hills One was about 1500 feet. I was flying my mini 2 at 150 altitude whilst we were up there. and about 50 meters away. I wanted to fly down the hill, But I then thought about RTH. If I had pressed RTH while the drone was in effect lower than me. Would it be reading the altitude as a lot higher than when I took off? Meaning, would the mini go to my preset RTH altitude? And go down, rather than up. Please don't shoot me down in flames for this "Stupid question"
David.
 
It would ascend to the preset altitude from the launching point
 
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Hi All. Just returned from the highlands of Scotland. We walked up a few hills One was about 1500 feet. I was flying my mini 2 at 150 altitude whilst we were up there. and about 50 meters away. I wanted to fly down the hill, But I then thought about RTH. If I had pressed RTH while the drone was in effect lower than me. Would it be reading the altitude as a lot higher than when I took off? Meaning, would the mini go to my preset RTH altitude? And go down, rather than up. Please don't shoot me down in flames for this "Stupid question"
David.
Luckily I don't think you need to worry about adding in additional altitude when your drone flies below ground level or the level which you took off (home point). Next time you are there, feel free to try it by hitting the RTH button (while you are connect and still in control) and watching your drone to see where it goes all the while you can pause or cancel the RTH after you are convinced how it works.
 
Luckily I don't think you need to worry about adding in additional altitude when your drone flies below ground level or the level which you took off (home point). Next time you are there, feel free to try it by hitting the RTH button (while you are connect and still in control) and watching your drone to see where it goes all the while you can pause or cancel the RTH after you are convinced how it works.

No need to experiment, the RTH altitude is relative to the elevation at the takeoff point. But it's definitely good to actually try out RTH and other safety features.

This does raise the question of whether the drone might exceed the maximum legal altitude, measured above the ground level below the drone, during it's return. If I set RTH altitude to 300' and fly down into a large 200' deep pit mine, and initiate RTH, the drone would climb to 300' above the takeoff point or 500' AGL before proceeding to the home point.

(I actually flew several hundred feet down into the gold mine at Cripple Creek and Victor, CO last summer. No RTH needed, though. Maximum depth of the mine is 2750'. Greatest width about three miles.)
 
All heights used by the drone are relative to the takeoff point, so, if RTH height was 197ft and the drone was at -300ft, the climb would be 497ft before it started to fly towards home. HOWEVER do be aware of the distance from home thresholds that apply.
 
Last edited:
would the mini go to my preset RTH altitude? And go down, rather than up.
Apart from what's already been said, your drone understands negative altitude.
FLying lower than your launch point won't confuse it at all.
 
Thanks, guys. That's all very comforting. I will take what you all say, into consideration. Sadly now back to not-so-hilly, silly Suffolk, in the UK.
David.
 

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