Above Mean Sea Level

Help
1

Hi,

I am using Air2 to fly the waypoint mission for my client. Client gave me altitudes of drone in Above Mean Sea Level AMSL, can Litchi understand AMSL? If not, how should I interpret these Alt into something that Litchi can understand?

Thank you.

2

No, Litchi does not work with MSL altitudes.

Sectional charts show altitudes using both MSL and AGL. You could use those values to convert the data.

2 Likes
3

Thanks.

Just to confirm: if client could give me the altitudes Above Ground Level, I still need to enable the Above Ground option in the mission hub to keep the desire altitudes client wanted which is the actual altitude/distance between the drone and the ground?

4

Yes.

If you haven’t read Wes’s documentation on “Above Ground” option, it will clarify a lot.

Read it here:

5

Thank you for the “Above Ground” explanation. I plotted out a short flight where I start off at 10 m above ground (with the tick on) - the 1st waypoint. After take off I fly 200 m into the sea - the 2nd waypoint where the hight is set to 30 m agl - where I turn left to waypoint nr. 3. I notice that at waypoint 1 Litchi indicates 10 m agl as set but at waypoint 2 it indicates 4 m below waypoint 1… I’m a bit lost here. I start off on the sea shore plus 10 m. But at waypoint 2 I’m 4 m lower?? Please explain… Regards!

6

Share the mission and indicate where your homepoint is. That’s the only way to help diagnose the problem.

7

Thanks! Help! How do I share a mission in here?
Regards!

8
9

Hi and thanks for the help. I include my intended flight mission. As mentioned I see that waypoint 2 which is over the sea surface indicates 12.6 m lower than waypoint 1 my start off point at 30 m altitude. My only fear is flying too low (over the sea). Is the sea surface also seen as “ground” level? Please have a look - I think I should be OK??

The Mission: Mission Hub - Litchi

Regards!

10

You should be OK. Flying over water is always a bit fretful, but your waypoint altitudes are set well above sea level.

WP1 is 12.6m above sea level. Yes, the sea surface is considered ground (sea level) hence the 12.6m drop from WP1 to WP2.

You’ll notice the indicated altitude of WP2 (looking at the mission map) is 47.4. 60m altitude setting for the waypoint minus the Ground Elevation difference of 12.6m
The drone will rise going from WP1 to WP2.

My only other advice… make sure your battery is fully charged before you take off. The sea is a harsh mistress.

11

Thank you very much!!!