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Measure flight altitude (general questions)

41Flyer

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Apr 20, 2019
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How does the Spark measure flight altitude? I am assuming that where it launches from is 0 and it goes up to 400' from there. So what if we launch from atop a hill/mountain? Still +400 from launch spot or does it take into account that it is sitting atop a 300' mountain?
Here in Texas, the area around me is really just +/- 10' so I don't have the opportunity to go outside to find out.

Does it also keep track of the ground by assuming the ground is at 0'? So if I am on top of a 50' cliff and launch, then try to fly down the side of the cliff, does some safety system kick in at any point? No cliffs around for me to really test with either. Also makes me wish the camera could "look up"

On the National Geographic channel, they did a show about the tallest redwood trees and mentioned some that were 370+ feet tall. Each time they mentioned that, all I could think about was how it might be tough to fly the drone over it (legally). We could tell LAANC we are flying below tree top. HAHA!
I need to travel some with this awesome flying camera!
 
Its only the altitude vs the home point. It doesn't adjust to elevation change. I did fly my spark in Big Sur California and dipped down below the cliffs I never actually payed attention to the listed altitude but it was at least 75ft below the take off altitude.
 
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On the National Geographic channel, they did a show about the tallest redwood trees and mentioned some that were 370+ feet tall. Each time they mentioned that, all I could think about was how it might be tough to fly the drone over it (legally).

You can fly over 400' legally over an object.
When within 400' of a structure, you rise to the top of that, plus an additional 400'.

 
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You can fly over 400' legally over an object.
When within 400' of a structure, you rise to the top of that, plus an additional 400'.

Me thinks that might be a slight misunderstanding. The 400' limit (USA) is 400' AGL (Above Ground Level) not 400' above whatever object you might be close to. Aircraft must fly at or above 600' AGL (except landing or emergency). That provides a 200' buffer between you and them. Just my understanding - no offense intended.
 
Me thinks that might be a slight misunderstanding. The 400' limit (USA) is 400' AGL (Above Ground Level) not 400' above whatever object you might be close to. Aircraft must fly at or above 600' AGL (except landing or emergency). That provides a 200' buffer between you and them. Just my understanding - no offense intended.

No offense, just a rule from the FAA.

Here's a link to an FAA document.

The second paragraph under Operating Requirements states the 400 foot rule.
 
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Since drones are extremely useful for inspections of towers, buildings, etc., the rule makes that activity legal. The FAA has shown time and again that they are doing their best to adapt to a rapidly changing technology.
 
Hobbyists are restricted to a maximum of 400 foot.

....until you reach an object or the terrain changes as you fly. Correct?

An example of this is if you launch by a lake in a valley and follow the terrain within 400' up to the top of a hill, you may be well above 400' from the launch point, but still within the 400' AGL.

Is the 400' AGL rule for the aircraft or the pilot in the valley?
 
....until you reach an object or the terrain changes as you fly. Correct?

An example of this is if you launch by a lake in a valley and follow the terrain within 400' up to the top of a hill, you may be well above 400' from the launch point, but still within the 400' AGL.

Is the 400' AGL rule for the aircraft or the pilot in the valley?
Aircraft, measured vertical from the aircraft’s ground position.
So, if you are climbing a mountain . . .

/\ | ——-
/ \ | 400’ ~<+>~
/ \|——-
/ \
/ \

Ok, the mountain doesn’t spread at the base like I actually drew it. Sorry!
I am NOT an artist, but I saw one in a gallery before!
 
It’s 400 ft above the ground or object. Be very careful flying into rising terrain. You may not notice how low you are until reviewing video. I think the 400 ft rule is inline with part 91 for fixed wing pilots which has altitude rules over city’s. 1000 ft over highest buildings and lightly inhabited areas are more loosely regulated. Endangering people or property. (The aircraft you’re flying is kinda thought to belong to the insurance company :(. Generally speaking you shouldn’t fly below 500 feet but there has to be some wiggle room for training. Emergency landings for instance.
I hope some common sense is applied to the drone regulations but pilots have to use some too.
 
I'm new to drone ownership, how strict is this rule? How is it enforced (radar?)? What is the penalty? Is there a thread that addresses this that someone could point me to?
 
Well, there's not much enforcement. And it's 400 ft above any object that you are within 400 ft of, hobbiest OR part 107 pilot.
 
remember when you are flying no matter where you are and even if you are below 400' all ( real ) aircraft , plains and helicopters have the right of way . don't think that 200' buffer makes you in the right and they are invading your air space . we have helicopters spraying for mosquitoes and planes towing banners over our field all the time ( sometimes a little lower than they should be ) . just a little tidbit of info .
 
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Drones yield to everything, and if there is an accident, it is your fault, even if you were 20 miles away (I exaggerate, but not much).
 

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