I'm new to flying drones, and I see that the software has an altitude limit one can set, and that some places have legal altitude limits, and the drone has a mechanical altitude limit, as well as potential issues with wind, signal reception, and/or not being able to see the ground well.

I am curious:

1) are those altitudes all above ground level (AGL), or above sea level (ASL)? (I think it must be above ground level?) Or are some AGL and some ASL?

(For example, if I'm at 1000 feet ASL, and set the max altitude to 2000 feet, it should go up to 3000 ASL, right?)

2) If the programmed limits are above ground level, what happens when flying over significant hills?
(For example, if I start at 1000 feet ASL, set the return home altitude to 300 feet, and then fly it up a hill to a point where the ground level is 1200 feet, and tell it to return home, will it rise to 1300 feet ASL to return home, or will it rise to 1500 feet to return home, and will it fly home at a constant altitude, or will it adjust to try to be the same height above the ground on the way back?)

3) Are there things I should be worried about, and/or guidelines for what should be a perfectly safe altitude to fly at (assuming weather is good and not windy), starting out at say 1000 or more feet ASL? I'm not sure how safe it is to fly how high.

Sorry if this is a bit of a complex question, and thanks in advance for any tips or info about this.

1) are those altitudes all above ground level (AGL), or above sea level (ASL)? (I think it must be above ground level?) Or are some AGL and some ASL?
All regulations are based on the height of the drone above the ground below it.
The limits in the drone and app are based on the height relative to your launch point (because the drone has no way to tell how far below the ground is).
But in most situations, that's probably close enough and you can adjust if it isn't.

2) If the programmed limits are above ground level, what happens when flying over significant hills?
Explained above.


3) Are there things I should be worried about, and/or guidelines for what should be a perfectly safe altitude to fly at (assuming weather is good and not windy), starting out at say 1000 or more feet ASL? I'm not sure how safe it is to fly how high.
Forget ASL ... it's 100% irrelevant.
Understand your local rules which include, don't fly higher than 400 ft above the ground below the drone.

As stated above, also, the best way to look at it is this, imagine a string thats 400ft long and tied to your drone, don't let that string leave the ground.

Bashy Posted at 12-27 19:33
As stated above, also, the best way to look at it is this, imagine a string thats 400ft long and tied to your drone, don't let that string leave the ground.

  That would be one long string Bashy.    Happy holidays mate.

DowntownRDB Posted at 12-28 10:47
That would be one long string Bashy.    Happy holidays mate.

That it would be, thankfully its imaginary else it could cause no end of issues lol

Happy Holidays to you to chap

Hi, there. Thank you for sharing your queries with us. Regarding your queries, please see the details below:

> The aircraft aircraft altitude from the take-off point is being calculated based on the AGL. Users can set the app for the maximum altitude.
> The RTH functions will depend on the flight environment and condition. Please refer to the images attached.
> Aside from the flight environment, you may check your local rules and regulations for possible restricted areas via this link.

I hope this information helps. Please feel free to reach us if you have further concerns.

Bashy Posted at 12-28 17:23
That it would be, thankfully its imaginary else it could cause no end of issues lol

Happy Holidays to you to chap

Stay warm and have a Happy New Year.  

Every height setting that you can set is realtive to the take off point and the drone measures that height by barometer. It does not really know anything about its AGL unless it is low enough for the ground to be within the range of its VPS senors but even then it does not tell you of this height.
Normally the drone's maximum height is limited by the setting YOU have set in the app but, with the Mini 2 SE, I am pretty sure DJI limit that setting to 500m or 1640ft.

The legal rule for you is 400ft, it is up to you to ensure compliance, the drone WILL NOT assist you is this respect in any way,

ASL does have relevance but ONLY when the take off point itself is VERY high, somewhere around 13,000ft, then the air may be too thin for the props to develop enough thrust to fly safely.

Height settings I generally use, under 100ft, or enough to clear an object by 30ft or so.
Pemember wind speed generally increases with height and an unnecessarily high RTH height wastes power in, if it is needed, the climb to RTH height and the descent FROM that height.
RTH height can not normally be higher than the maximum height.