[size=14.6667px]I was out flying my new (to me) P4P and began paying attention to the on screen telemetry.  This is only my second session with the new bird so its all a bit new to me.  It flies and answers the stick controls in awesome fashion however I did notice that the reported VPS altitude is not accurate.  Ascending to 20 ft. looks okay at first.  Take it up to 50 ft and it says 26 ft. Fly it forward a few meters and it bounces up to a higher number.  Question is:  is this an inherent flaw in the P4P?  Is my drone defective?  Very concerned

VPS is not accurate above about 10 feet. So don't be concerned. In fact it does not even work much above that altitude.

Geebax Posted at 2017-11-20 19:34
VPS is not accurate above about 10 feet. So don't be concerned. In fact it does not even work much above that altitude.

Thanks Geebax, I was able to figure out that I was looking at Vision Positioning and not an actual altimeter which apparently does not exist.  

Anokadrone Posted at 2017-11-21 09:46
Thanks Geebax, I was able to figure out that I was looking at Vision Positioning and not an actual altimeter which apparently does not exist.

The aircraft relies on a barometric altimeter, and it is this value that is display primarily on the screen. It reads the altitude above the point at which the aircraft takes off.

Anokadrone Posted at 2017-11-21 09:46
Thanks Geebax, I was able to figure out that I was looking at Vision Positioning and not an actual altimeter which apparently does not exist.

Your Phantom has an altimeter but you can't calibrate it to show altitude above sea level.
Altitude above sea level may be useful for a plane that can fly at 10000 feet and travel hundreds of miles in a flight.
But it isn't really relevant when you are flying a small drone with limited range and altitude.
Height above your local terrain is much more important.
Unless you fly in an extreme area, height above homepoint is close enough to height above terrain for you to calculate any extra you need to consider.

Labroides Posted at 2017-11-21 15:04
Your Phantom has an altimeter but you can't calibrate it to show altitude above sea level.
Altitude above sea level may be useful for a plane that can fly at 10000 feet and travel hundreds of miles in a flight.
But it isn't really relevant when you are flying a small drone with limited range and altitude.

I am not quite following you.  Are you saying that there is an altimeter reading on the main screen?  If so, I will find it but I did not see it the last time I flew.  Also, if there is a reading, the altitude above home point would be be just fine since the FAA reg is stated in as 400' AGL (above ground level)
Thanks all

The VPS may not work well in the below situation, and I'll attach the screenshots of User Manual for your reference:

Anokadrone Posted at 2017-11-22 04:29
I am not quite following you.  Are you saying that there is an altimeter reading on the main screen?  If so, I will find it but I did not see it the last time I flew.  Also, if there is a reading, the altitude above home point would be be just fine since the FAA reg is stated in as 400' AGL (above ground level)
Thanks all

Are you saying that there is an altimeter reading on the main screen?  If so, I will find it but I did not see it the last time I flew.

Look at the bottom of the screen.
See the numbers there?
The one with a large D is Distance away
And the one with a big H is Height (above home point)
Next time you fly, watch the numbers and see how they change.

Labroides Posted at 2017-11-22 06:29
Are you saying that there is an altimeter reading on the main screen?  If so, I will find it but I did not see it the last time I flew.

Look at the bottom of the screen.

Thanks again, too much going on when I am in the air.   I guess I am just too busy flying the drone and just glancing at the screen.  I guess I need to look a little harder.   Sorry for my confusion,  I feel kinda 'tupid