Flying over deep canyons risk

[sar104]

What if this was a Litchi mission with the "above ground" box checked?

The aircraft still doesn't know about AGL - all that happens with that kind of Litchi profile is that Litchi looks up ground elevations and adjusts the aircraft height, relative to the first waypoint, appropriately.

 

[cloneme]

Incredible place to fly ... I don't know if you are new to drones in general, or just new to the Mavic 2 - but one thing to think about here is that it's going to be a long and difficult walk to get the Mavic back if it goes wrong! So get 100% familiar with you pre-flight checks and settings before your fly off into that space!

Incredible place to fly ... I don't know if you are new to drones in general, or just new to the Mavic 2 - but one thing to think about here is that it's going to be a long and difficult walk to get the Mavic back if it goes wrong! So get 100% familiar with you pre-flight checks and settings before your fly off into that space!

I am new to drones and the mavic 2 pro is my first drone, just thought I would jump in at the deep end. Anyhow had a few test flights before I went down to my daughters property to fly. I am lucky that I can go whenever I like the plenty of room down there. Also I might add that I get around on crutches and electric wheelchair so I won't be absailing over the cliff. I did a lot of reading before set sailing into the wild blue yonder and do all the pre-flight tests. In fact I have one of those landing pads and when I had the drone a few hundred metres away I pressed the return to home button and it came back and landed right in the middle of the landing pad, I'm a very chappy.

 

[FoxhallGH]

I am new to drones and the mavic 2 pro is my first drone, just thought I would jump in at the deep end. Anyhow had a few test flights before I went down to my daughters property to fly. I am lucky that I can go whenever I like the plenty of room down there. Also I might add that I get around on crutches and electric wheelchair so I won't be absailing over the cliff. I did a lot of reading before set sailing into the wild blue yonder and do all the pre-flight tests. In fact I have one of those landing pads and when I had the drone a few hundred metres away I pressed the return to home button and it came back and landed right in the middle of the landing pad, I'm a very chappy.

OK - I'm just aware that we do see a lot of posts here that tell stories of RTH (Return To Home) that went wrong. 9.9 times out of 10, this turns out to be because the Operator did not take the time or do the right steps to make sure that the drone was set up to do the RTH!
One of the forum members - MavicHelp - has posted this very helpful guide in the past. It's been useful for me, and I hope it can be the same for you.
Prevent a Crash or Flyaway with Your Mavic | Mavic Help
As a rule-of-thumb, if you make sure that; a) you hear/see confirmation that the Mavic has fixed its GPS reference point before you launch, and b) ascend vertically to 30ft (without any yaw or roll) to allow the Mavic to get a good view of the ground reference for the RTH - then you should have an accurate return. Also - make sure you have the settings all OK for your RTH height in Go4 - and remember that these altitude settings all refer to your take-off point i.e. if you fly down into the canyon, Go4 will be showing you negative altitude, and when you do RTH, the Mavic will rise through zero and up to the set height [above take-off zero].

 

[cloneme]

Thanks FoxhallGH, I will take on board your advice and all others who have given theirs. This is a great Forum and I hpe to post a video O my next excursion.

 

[Coolwater]

I am a new owner of a mavic 2 pro and have flown it a few times successfully . I would like to fly it over my daughter's property (340 acres) but one boundary is a sheer cliff some 300m to a river and we would like to be able to get a video over the edge. My question is, would flying over a sudden drop which would mean the drone's senses that the height has gone from say 100m to 400m would there be a correction and the drone would drop?

I’ve flown in and around a lot of similar terrain and the advise you have gotten is great. One more thing to learn from my personal experience is... I launched in a deep canyon and the drone would not fly higher than 15 feet because it could not get adequate GPS signals. I missed some awesome shots because of this. I later launched from above the canyon and dropped in and that worked much better.

 

[RonBower]

To reply to the original poster, I recently flew over a canyon. I'm certainly not an expert, especially in the areas of barometric pressure and the resulting drafts. But my thought was to fly straight out from the edge and actually get out toward the middle of the canyon where the air might be more calm. I was happy enough with the photo perspective, and didn't feel the need to descend much. But the flight itself was routine and didn't present any unusual issues. I believe I could have descended a fair amount as long as I kept a clear line back to my controller. This is several shots stitched together. A little fear and caution is a good thing, in my opinion.

 

[roadkilt]

I fly in narrow river canyons a lot and losing GPS signal is the first issue, then the Air shifts into pilot control mode so you better be good at flying, then it gets jittery if over moving water in the canyon bottom. As a previous poster noted it may kick you into a height restriction of 15m as well. When you are in atti mode and actively flying you really find out about the many little wind currents in the canyon you normally dont know about because the MA is locked in to position or is flying itself basically. Its all great really, just way more engaging and dont be doing this until you have a lot of flying time (and its not your first drone...i guarantee you’ll lose it)

 

[PT_Mavic]

Your drone has no sensors that could tell that it's height above the ground has changed from say 100m to 400m.
Plus .. it's a flying machine, not a following terrain machine.
It will act just like a bird or airplane flying past a cliff edge.

It is possible to mod Go4 (with NLD) to display altitude above ground level; mine shows that instead of height above takeoff point. You have to load regional terrain data (free from, as I recall, USGS) which is matched to current GPS coordinates. It works surprisingly well and is quite responsive as my Mavic moves.

 

[PT_Mavic]

To reply to the original poster, I recently flew over a canyon. I'm certainly not an expert, especially in the areas of barometric pressure and the resulting drafts. But my thought was to fly straight out from the edge and actually get out toward the middle of the canyon where the air might be more calm. I was happy enough with the photo perspective, and didn't feel the need to descend much. But the flight itself was routine and didn't present any unusual issues. I believe I could have descended a fair amount as long as I kept a clear line back to my controller. This is several shots stitched together. A little fear and caution is a good thing, in my opinion.
View attachment 67655

That's a beautiful composite!

 

[John Suhr]

Thank you for your reply and have taken note, I think I might just stick to the edge

Be careful on the edge of cliffs for thermals, they can dominate the drone.

 

[RonBower]

That's a beautiful composite!

Thank you! It was actually 3 shots (rotating the drone maybe 30 degrees to the right between shots), and then stitched the photos together in LightRoom. I'm not sure why I was so afraid to fly over the canyon, but I was.

 

[Meta4]

I launched in a deep canyon and the drone would not fly higher than 15 feet because it could not get adequate GPS signals. I missed some awesome shots because of this.

You are limited to 5 metres without GPS if you have the VPS enabled.
But you could have flown to 30 metres if you had disabled VPS
(p56 of the Mavic 2 manual)

 

[Mavrick77]

I am a new owner of a mavic 2 pro and have flown it a few times successfully . I would like to fly it over my daughter's property (340 acres) but one boundary is a sheer cliff some 300m to a river and we would like to be able to get a video over the edge. My question is, would flying over a sudden drop which would mean the drone's senses that the height has gone from say 100m to 400m would there be a correction and the drone would drop?

No

 

[kilomikebravo]

A little fear and caution is a good thing, in my opinion.

I couldn't agree more, Ron and boy oh boy is that ever a great photo!

 

[Gooseman]

Good point about thermals! Part of my CAA course related to katabolic wind issues. really worth reading up on this as they change depending on the season, time of day, temperature shifts etc.

Weather Facts: Katabatic winds | weatheronline.co.uk

Katabatic wind (from the Greek: katabaino - to go down) is the generic term for downslope winds flowing from high elevations of mountains, plateaus, and

www.weatheronline.co.uk

 

[CanyonRunVideos]

I am a new owner of a mavic 2 pro and have flown it a few times successfully . I would like to fly it over my daughter's property (340 acres) but one boundary is a sheer cliff some 300m to a river and we would like to be able to get a video over the edge. My question is, would flying over a sudden drop which would mean the drone's senses that the height has gone from say 100m to 400m would there be a correction and the drone would drop?

That will not happen. Remember that the flight control system are tracking your drone using GPS from 200 miles away in space. Even if your UAS lost all GPS connections the UAS onboard flight control system will keep you on the current altitude.

 

[Meta4]

That will not happen. Remember that the flight control system are tracking your drone using GPS from 200 miles away in space.

GPS satellites are slightly further away that that. They are orbiting 20,180 km (12,540 mi) from earth.