Altitude Above Ground

[Desertspark]

Assuming the Spark is self-limited to 400' above ground level, what happens if you're flying in mountainous country? For example, you fly off a "Scenic Overlook"over a valley that drops more than 400' . Does the Spark think it's flying above its self-limited altitude and drop to its 400" ceiling and be unable to fly up to its launch site because it's more than 400' above the valley floor?

 

[SoccerRef12]

AGL is from where you take off. My house is on a hill and when I fly down to the pond I think it shows minus altitude. Maybe someone smarter than me can correct if I'm wrong.

 

[SPark_South_Oz]

If max altitude is set to 120m (400') ceiling, then all DJI aircraft will recognise this from the Home Point / TOP (take off point).

You can fly up to 500m (~ 1640') above TOP via the app settings, good for where you take off from a lower altitude, and fly up the side of a mountain, you can technically keep going above the legal (in most places) 400' altitude AGL limit, as the terrain increases in height. Up to 500m.

Likewise, it you take off from a Home point at say 600' and fly down into a valley, you should legally maintain 400' about the ground below the aircraft, not easy to do, an estimate has to be made by the pilot.

This is a good diagram of altitude in legally restricted 400' drone airspace.

 

[dougiefresh27]

I have the opposite problem. Here, if I take off and fly up to a tall bluff, I can hardly fly higher. Since it registers my launch point as ground. It doesn't know the elevation of terrain below it

 

[Spark 317]

I have the opposite problem. Here, if I take off and fly up to a tall bluff, I can hardly fly higher. Since it registers my launch point as ground. It doesn't know the elevation of terrain below it

Change your maximum flight altitude in the Go4 app.

I have to do this when vacationing at the lake and launch from the shore line to travel up the hillside (within 400') to the top where I can see over the ridge.

The Spark may be several hundred feet up from my launch point, but still within 400 ' AGL.

You're not supposed to go straight up and over, but if you fly within 400' of the terrain, you're safe.

 

[SPark_South_Oz]

Good advice @Spark 317 the app allows to open up max alt to 500m, about 1640'.
Usually enough for a Spark to get up to most tall features and gradual ascent takes you up sloping terrain.

It's possible to go even further than the 500m . . .

I've seen many threads on MavicPilots that also go on to say you can actually land, at say 450m, obviously somewhere signal won't be lost, take off again, and it will then allow a further 500m from that point, so tall mountains can be 'scaled'.
I've never tried this, but it does work, and I don't think you need to power down . . . just land and it records landing, then restarts alt count on take off.
Obviously easier with ocusync drone, but in right circumstances could be done with good wifi connection.

Would need testing in a miniature situation with great control to make sure the process is done right.

 

[Spark 317]

and it will then allow a further 500m from that point, so tall mountains can be 'scaled'.

That should work but keep in my mind that when the battery gets low, the aircraft will go back to the last Home Point you leapfrogged to.

It may not make it all the all the way back to the original HP where it was launched.

 

[SPark_South_Oz]

That should work but keep in my mind that when the battery gets low, the aircraft will go back to the last Home Point you leapfrogged to.

It may not make it all the all the way back to the original HP where it was launched.

Definitely an aspect to be aware of !!

It will probably show HP distance as the new take off point too.
Worth confirming in safe testing location, using short distances . . .

If this did reset the HP location, distance to home etc, one thing you could probably do after 2nd take off is set HP as controller location.

 

[dougiefresh27]

Change your maximum flight altitude in the Go4 app.

I have to do this when vacationing at the lake and launch from the shore line to travel up the hillside (within 400') to the top where I can see over the ridge.

The Spark may be several hundred feet up from my launch point, but still within 400 ' AGL.

You're not supposed to go straight up and over, but if you fly within 400' of the terrain, you're safe.

Such a simple solution. My mind is stuck on what the craft would report I guess. I do keep detailed flight records but in a case like that I could note the terrain and make sure that I maintain below 400' AGL. Thanks my friend!