I Have a Dumb Question about altitude

[umanbean]

Does the drone measure the altitude from its take-off point,

Yes

 

[jffprc]

I-fly in Colorado taking off 10,000 feet above sea level, then fly up the side of the mountain staying under 400 feet above the ground and reaching 11,500 feet above sea level with no problems

 

[Meta4]

Just curious: Does the drone measure the altitude from its take-off point, or does it know what the altitude of the land is underneath where it is flying.

All heights are relative to the launch point.
Home = zero.
Your drone has no understanding of the surrounding terrain.

I wonder if the drone could show a warning in this type of scenario.

As demonstrated by other incidents of this warning (see post #33), it's a meaningless, nonsense warning, that can show up anywhere.

 

[MAvic_South_Oz]

Just curious: Does the drone measure the altitude from its take-off point, or does it know what the altitude of the land is underneath where it is flying.

Always from take off point if you get the gps lock fine and home point recorded there.
If you take off before full gps lock, then when it does get recorded it registers from that particular spot.

 

[Meta4]

Always from take off point if you get the gps lock fine and home point recorded there.
If you take off before full gps lock, then when it does get recorded it registers from that particular spot.

No .. Zero altitude is completely separate from the home point.
Zero altitude is established when you power up the drone.
It has nothing at all to do with GPS.
The GPS receiver takes longer to establish contact with GPS satellites, but GPS is only for horizontal positioning, not altitude, which comes from a different sensor.

 

[MAvic_South_Oz]

No .. Zero altitude is completely separate from the home point.
Zero altitude is established when you power up the drone.
It has nothing at all to do with GPS.
The GPS receiver takes longer to establish contact with GPS satellites, but GPS is only for horizontal positioning, not altitude, which comes from a different sensor.

Ok, I'll check next time out, thought it would be when it recorded HP.
I must admit I can't even remember taking off without GPS though.

 

[Meta4]

Zero altitude and home point are two different things from two different sensors.
Your home point has no altitude, just X and Y co-ordinates.

 

[okw]

granted I would still be ok since I'd only be 200 feet from the side of the mountain)

It appears that you're in the US, in which case this does not apply. There are some countries that would allow for flying within 400' (120m) from a vertical cliff, regardless of how high above the ground it was. However, in the US, the altitude restrictions for recreational flying are always measured to the ground directly below the aircraft.

 

[The HardWay]

It appears that you're in the US, in which case this does not apply. There are some countries that would allow for flying within 400' (120m) from a vertical cliff, regardless of how high above the ground it was. However, in the US, the altitude restrictions for recreational flying are always measured to the ground directly below the aircraft.

So say you're on the edge of a 1000' cliff that dropped off completely vertical...
You set your drone 1 foot back from the edge, take off and hover 3 feet above the ground. Then you fly forward 2 feet and are hovering over the edge and now are now flying illegally? That is dumb. Then again, it's a rule from our lovely federal government.

 

[Meta4]

So say you're on the edge of a 1000' cliff that dropped off completely vertical...
You set your drone 1 foot back from the edge, take off and hover 3 feet above the ground. Then you fly forward 2 feet and are hovering over the edge and now are now flying illegally? That is dumb. Then again, it's a rule from our lovely federal government.

It's just a dumb hypothetical question for people who are unable to use common sense.

 

[The HardWay]

It's just a dumb hypothetical question for people who are unable to use common sense.

Well sorry then. I live in an area were there lots of canyons. Might be flying over an area a couple hundred feet up, but then the topography drops off 300' and then back up on the other side, so was wondering.

 

[Meta4]

Well sorry then. I live in an area were there lots of canyons. Might be flying over an area a couple hundred feet up, but then the topography drops off 300' and then back up on the other side, so was wondering.

Do you have many planes that fly a few feet off a vertical cliff there?
Do you have many FAA inspectors with abseiling equipment and a big tape measure there ?
Use a little common sense.

 

[Kywon McCain]

To you, it's 400 ft
To the drone its 11,000 feet because you took off from a elevated ground that's 11,000 feet high so the app is going to blow up in your face about it. To fix it, well for me at least, you can increase the max altitude above 400ft. You'll get a on screen warning while your doing it saying the max altitude your setting is above 400 ft oh yes it might work

What's a dumb question?

 

[Meta4]

To you, it's 400 ft
To the drone its 11,000 feet because you took off from a elevated ground that's 11,000 feet high so the app is going to blow up in your face about it. To fix it, well for me at least, you can increase the max altitude above 400ft. You'll get a on screen warning while your doing it saying the max altitude your setting is above 400 ft oh yes it might work

What's a dumb question?

You didn't read the three pages of the thread, did you?
Launching from 11000 ft shouldn't be (and isn't) a problem.
See post #33.

 

[Kywon McCain]

You didn't read the three pages of the thread, did you?
Launching from 11000 ft shouldn't be (and isn't) a problem.
See post #33.

Um yes uh. What I saw was you arguing with a bunch of other people about planes flying off cliffs, common sense, and what not. Also other people on this post are saying they have alt warning from the problem I just described. I'm not joining argument pls I can't afford it

 

[Uncle Hoser]

Best answer, as usual...

People call me to come work on their computer. When I get there, they say "It said so-and-so, or something like that"... Well, without knowing the exact message, how can I fix it? I charge by the hour, so I just dig in and start figuring it out and by the time I done, it costs the customer a lot more that way.

Fortunately, drones have logs.

I feel your pain! ... "It popped up a screen that said something like whatever (insert gibberish)"...always a moneymaker!!!