Hello all,

I am hoping someone can help me with an issue I am having with my Mavic Pro.

For the last 5 months, I have flown a path around a construction site each week using a Waypoints mission.  I fly the exact same Waypoints mission each week.  However, last week, when I flew the mission, the actual elevation is different, although the elevation programed into waypoints has not been changed.

The mission is programmed to fly at 50 feet.  However, if you look at the 2 pictures, you can see that the actual elevation of the 2nd photo is lower than the 1st photo (even though it was the same waypoint mission).  I noticed this because the drone nearly crashed into a telephone pole that would have been a disaster, and possibly a serious incident.  Fortunately it did not crash, but it made me realize that even though the drone flew the exact same Waypoints mission, that was scheduled to fly at the same altitude (programmed for 50 feet), the drone flew at a different elevation in reality than it had flown at for the past few months.

I can't figure out why it is now flying at an actual elevation lower than it had during all previous waypoint missions.

A few additional pieces of information:
- Waypoint mission was not adjusted, and I started it through my app in the same way that I always had for the past several months
- Location of takeoff was identical.  I stand in the exact same spot each week when I take off, so it wasn't like I was standing at a different elevation at take off.

I can't understand why the drone is now saying it as at 50 feet for the waypoint mission, like it always did previously, but now the actual height of the drone is flying much lower, and at risk of hitting a telephone pole that previously it was always well above.

Any idea what could be causing this, or how to fix it?

Thanks!

Hi,

Flyheight has the zero height reference at the height it did take-off.

Same position and same height drone to the ground? ( ground take-off and hand take-off or ?)
If you post both flightlogs, mayby they explain why there is a difference.
cheers
JJB

If you are trying to shoot a drone time-lapse, the aircraft will not accurately find the same point either in position or altitude. It is simply not designed to do so. There are actually cameras designed to do building site time lapses, probably fitted to that pole in view.

Check to see if there is any dirt on the sensors on the bottom of the drone.  Maybe GPS wasn't working correctly that day.  Just guessing.

KenDuke Posted at 3-2 06:19
Check to see if there is any dirt on the sensors on the bottom of the drone.  Maybe GPS wasn't working correctly that day.  Just guessing.

Hi Ken,

Dirt on bottom sensors : effect on VPS height, not on barometric height.
GPS has nothing to do with barometric sensor.

Height is controlled by barometric sensor. FlyApp doesn`t show VPS height.

cheers
JJB

Verily I sayeth unto thee, abide by Litchi for waypoint missions, and partaketh yee of no other temptation.  Litchi doth stayeth true to thine original flight plan, and shalt not waver, ever.