Altitude

[Meta4]

I think it depends how it is used. With 15+ sats, there has to be a good least squares 3D centroid where the Phantom resides. The processing capability to correlate the position might be lacking.

With consumer grade GPS, altitude accuracy is woeful.
As explained here: How accurate is the GPS elevation reading?
Garmin advises ... the accuracy permitted by geometry considerations remains less than that of horizontal positions. It is not uncommon for satellite heights to be off from map elevations by +/- 400 ft. Use these values with caution when navigating

 

[yawnalot29]

oh you guys are going to love this....

This is on my P2V+ that made its last flight. The last flight went something like this:

I took off from a house on a hill over looking Pacific ocean in Southern California. I think house is 650 feet above sea level.

Flew straight up in GPS mode to until reading says 150 feet. Have about 11 sat lock.

Head out toward the ocean. It got to coast line fine.

Turned around, flip to ATTI mode to it can fly back faster confident in thinking it would clear any tree and such.

Let's just say it crashed into hill side at about 500 feet above sea level.

SO a net difference of about 300 feet. Good times. Now I have P3P.

 

[Noodle]

It need be no bigger than the ultrasonic module already attached. I don't know why they don't use that for altitude reading it works in a similar way but range would be very restricted.

But I suspect radar and laser won't be accurate when flying over water.

 

[Wibble]

But I suspect radar and laser won't be accurate when flying over water.

Actually they are MORE accurate off water as it is a nice smooth flat reflector.

 

[Meta4]

Turned around, flip to ATTI mode to it can fly back faster confident in thinking it would clear any tree and such.
Let's just say it crashed into hill side at about 500 feet above sea level.

The P2 series was well known for losing altitude in atti mode - but the telemetry should have still shown the correct altitude.

 

[yawnalot29]

The P2 series was well known for losing altitude in atti mode - but the telemetry should have still shown the correct altitude.

Was busy trying to spot the P2V+ above me as it got closer then I heard the sound of impact.......

Here's to P3P

 

[pe9999]

Not sure about temperature changing. I live in Miami Florida and it is constantly hot. Today for example it is 82° and I'm in rural farmland ( Redlands). Flat as it comes.

Otherthan temperature, air speed also impact the barometer, have you noticed when the quad is moving forward, it dips in attitude