How low do you go on Litchi waypoint missions?

[jmagee]

I find that although higher flights are safer (naturally), lower flights give more exciting-looking videos as you skim the tops of the trees.

Up until now I have never gone below 200 feet on Litchi waypoint missions, but the results look pretty tame. I keep thinking about flying a mission, examining the footage to see how much clearance I'm getting, then doing another mission with the same waypoints, but shaving, say, tewenty feet off the altitiude, then if that seems to give a safe result judging from the video, shaving another twenty feet off, and so on. Trouble is, this relies on the bird's altimeter being accurate and consistent, and I've heard that barometric altimeters just aren't all that accurate.

Bearing all this in mind, I'd be very interested in hearing how low people here risk flying on a Litchi waypoint mission.

 

[MacCool]

Lots of trees here in Minnesota. I fly the drone up manually on a given Litchi course to see what altitude the treetops are, then add 10 feet. Flying across the lake, I've set Litchi altitude as low as 10 feet trying to capture early morning mist.

 

[jmagee]

That sounds pretty scarey to me - I mean, just adding ten feet. I've heard that the altimeter in the P3 can vary up to 50-60 feet, so if I tried with that little clearance, I'd be gritting my teeth the whole time, expecting it to crash at any moment.

That said, I have to admit I'm a bit of a coward (and a pessimist) when I fly Litchi missions: even though up to now I have added 150 feet clearance for everything in its path, I'm always nervous when I launch the mission, and if I hear that voice say 'signal lost', I always think I'm never going to see the bird again.

 

[Richard R]

Saying that a baro altimeter isn't accurate is too simplistic. I've piloted full sized aircraft many times using the onboard baro to maintain altitude and to land safely. More accurate to say it isn't compensated. That is, no adjustments are made for changing temperature or air pressure. But that really only matters when you are going to be airborne for some longer period of time and move a significant distance from your takeoff location. Flying something like a phantom for 15-20 min and landing back where you started, compensation doesn't really come into play. Short term relative accuracies of a foot or two shouldn't be unrealistic. But remember all of the altitude reporting by Go or Litchi is relative to the takeoff point. So the phantom is pretty good at maintaining a constant altitude over a short time such as a single battery mission. Probably more accurate than the side-to-side location accuracy that relies on GPS. so I would 'Trust' my altitude, and be more concerned about and trees to the side of my path that might sneak out to grab you if you wander too close.

 

[alokbhargava]

First of all it's so difficult to judge the heights of trees and high structures, I would always keep a safe distance considering judgement errors and altitude measurement errors. Keep 50' a safe distance.

Another aspect to be considered is that all altitudes are decided with respect to the home point, that's the starting point and we need to consider the ground level elevations too into considerations. If you take off from a different point on the ground, all altitudes will be different.


Sent from my iPhone using PhantomPilots

 

[GMack]

I've had my take off and landing altitudes differ by ~60 feet over a mile long flight, usually towards the negative side too. It's not military grade gear so be careful.

 

[royster]

I see the latest Litchi upgrade says- "added altitude of AC at each waypoint".
Each waypoint altitude would be calculated relative to your home point, altitude?
or am I off?

 

[Pharm]

I see the latest Litchi upgrade says- "added altitude of AC at each waypoint".
Each waypoint altitude would be calculated relative to your home point, altitude?
or am I off?

Where are you seeing this? My Litchi updated 2 days ago and I don't see that under "What's New". The altitude at each waypoint has been a feature of Litchi as long as I've been using it (many, many months) and yes, it's altitude relative to the home point.

 

[MacCool]

That sounds pretty scarey to me - I mean, just adding ten feet. I've heard that the altimeter in the P3 can vary up to 50-60 feet, so if I tried with that little clearance, I'd be gritting my teeth the whole time, expecting it to crash at any moment.

That said, I have to admit I'm a bit of a coward (and a pessimist) when I fly Litchi missions: even though up to now I have added 150 feet clearance for everything in its path, I'm always nervous when I launch the mission, and if I hear that voice say 'signal lost', I always think I'm never going to see the bird again.

I can't speak to the P3. I use a P4. With that drone, I have utter confidence in my 10-foot margin based on almost 100 flights skimming the lakes and treetops of Minnesota.

 

[royster]

Updated Litchi last night in the release notes- Added altitude,etc, etc-now, I;ve been away from Litchi for a month, so maybe just new to me

 

[Rudster]

Hello from NB Canada. New to Litchi, approx 3 auto flights to date,,,,wow, Yes Low Flights? My next test flight will have 5 waypoints,altitude set at 4 meters at 9km/hr. Terrain is fairly level,but will be keeping a close watch throughout the mission. Question? If at any point during mission my P3P goes to close to grass or,,,,trees,,,can I override with my control sticks? If not, I know I can stop mission by switching back to P mode and regain manual stick control. Also I've learned to takeoff and fly near 1st waypoint in P mode, then switch to F mode to initiate auto mission to avoid any tall monsters between homepoint and waypoint #1. Thanks, Rudy.