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Lost GPS = No RTH, why? Not an actual incident, just wondering.

Impossible. There's no way to sense AGL.

This points out the risk of setting RTH altitude, relative to takeoff altitude, close to 400ft. Depending on the terrain traversed on the way back, it's easy to exceed 400ft AGL, violate the rules, and even intrude into manned aircraft space.

I set my RTH between 150-200' depending on the flight.
I obviosly don't fly in the type of terrain you do. I live in florida. It's one big flat pancake with a few hilly areas. You must fly over a lot of valleys and low ground level areas. How do you adjust your flight level if you're flying at say 375 ft. If you hit a dip in the terrain, the barameter in the drone will kepp reading 375ft. The only way you can fly legally, by your own admission , is to fly way below 400 ft at all times.
 
The point was to get it back within radio communication range so that you could regain control. You don't need pinpoint accuracy to attempt that.

Right. For that it would be better than the current behavior.

However, given my understanding of the capability of the IMU hardware in our drones, it would be a tough job in a gusty, windy environment.

I'm thinking it would be a real challenge at one of DC Rainmaker's wind tests at that lighthouse 😁😁😁
 
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I obviosly don't fly in the type of terrain you do. I live in florida. It's one big flat pancake with a few hilly areas. You must fly over a lot of valleys and low ground level areas. How do you adjust your flight level if you're flying at say 375 ft. If you hit a dip in the terrain, the barameter in the drone will kepp reading 375ft. The only way you can fly legally, by your own admission , is to fly way below 400 ft at all times.

You got it. The coastal area here in Santa Cruz, CA going straight inland from the ocean varies hundreds of feet.

My most oft flown area, Seacliff, literally has a cliff that drops 75 feet vertical down to the beach. I can be 350 AGL on one side of that edge, and instantly be 425 AGL and in violation after crossing it.

I hear ya about FL. Or Iowa. When it's flat for miles and miles, the 400' rule is vastly simpler to comply with.

That said, it's not really an issue. For me, the interesting flying is far below 400'. I've been flying quads for ten years and got the altitude thrill out of my blood a long time ago (with a hacked Mavic Pro and a personal record altitude that will remain classified 😁).

I rarely go much over 200' because most of the time the interesting pictures and video are within 100', maybe even 50-75'. At those heights, flying's a fun challenge. Good imagery will most of the time involve some skill and challenge flying.

That's why DJI has invested so much in technology to aid this sort of flight.

And then there's FPV, where I spend most of my flying time. There's no point in 400'. Or 300. Or most of the time, even 100. Yeah, I shoot up to 100-200' regularly, but only briefly as part of zooming around. 99% of FPV time is well below that.
 
If your drone loses GPS and signal, will it land immediately, or at least climb first to the established RTH altitude. I can see situations where it would lose GPS due to buildings, etc. but could possible regain GPS for proper RTH flight, if it first climbed to the established RTH altitude. Never been in a situation where I've lost both signal and GPS.
 
I fly drones for our Fire Department and I have to disable OA. If a smoke plume envelopes the drone it will not move. That can be very scary when trying to get out of the way of hot smoke plumes even at 350 ft AGL.
 
I fly drones for our Fire Department and I have to disable OA. If a smoke plume envelopes the drone it will not move. That can be very scary when trying to get out of the way of hot smoke plumes even at 350 ft AGL.

Wow! Never thought of that, but of course makes perfect sense.
 
If your drone loses GPS and signal, will it land immediately, or at least climb first to the established RTH altitude...
It will pretty much land immediately while drifting with what ever affecting it... the drone will not do anything at all to either regain RC connection or GPS reception.

You can say, that it will no longer try to save the drone, instead the main focus is to get a a drone without command & means of reliable navigation out of the sky as quickly as possible to cut the losses regarding everything else around it.
 
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If your drone loses GPS and signal, will it land immediately, or at least climb first to the established RTH altitude.
If the drone ascended, that would be because RTH initiated, but if there is no GPS and loses signal, RTH doesn't initiate, it doesn't climb and lands where it is.
Never been in a situation where I've lost both signal and GPS.
Almost no-one has.
It's a very rare situation.
 
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If the drone ascended, that would be because RTH initiated, but if there is no GPS and loses signal, RTH doesn't initiate, it doesn't climb and lands where it is.

Just to be clear, this is a new scenario to me: If you lose connection and GPS, the drone will (after some timeout period) descend and land wherever it is?

This is good to know...
 
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