Litchi way points missions - How accurate is the time displayed in mission hub to actual flight?

[Deleted member 94047]

After 6 months of flying the Mavic Air with DJI Go, I am jumping ship to Litchi. Just purchased the app and will be doing some experimental way points missions soon. One thing I can't really find info on is the duration of missions in the plan vs actual flight. If for example the mission plan says it will take 12 minutes for a mission to complete, how much more/less time will that be during actual flight? What is your experience?

Also, any other advice from experience will be greatly appreciated. Thanks!

 

[Kazzaaz]

Generally it gives you a conservative estimate, but don't dive right into long-range waypoint flights before you test for yourself! Start local and gradually expand your missions from there. And always be aware of the wind!

In my experience I typically complete missions in about 80-85% of the estimated time. With a full battery and calm conditions, I did enough testing to where I'm comfortable flying missions predicted to take <25 min or so.

The MA's battery won't be able to fare quite as well, so you'll have to report back with your own findings.

 

[Deleted member 94047]

Generally it gives you a conservative estimate, but don't dive right into long-range waypoint flights before you test for yourself! Start local and gradually expand your missions from there. And always be aware of the wind!

In my experience I typically complete missions in about 80-85% of the estimated time. With a full battery and calm conditions, I did enough testing to where I'm comfortable flying missions predicted to take >25 min or so.

The MA's battery won't be able to fare quite as well, so you'll have to report back with your own findings.

Thanks Kazz; that was exactly the kind of advice I was looking for. I will start with 5 - 8 minutes missions and see how it goes.

 

[Kazzaaz]

Sounds like a good plan!

33mph is the maximum speed for a Litchi mission, and with little wind the speed is no problem for the M2. (never flown an Air, so maybe take this with a grain of salt)

actually for the M2 It seems to be a pretty ideal speed - I can get at least 20 minutes of "straight there and back" flying before I'm out of juice. 20 minutes at 33mph is 11 miles.

This doesn't account for time spent ascending and descending among other actions that aren't just flying in a straight line, but if you go ahead and plot an 11 mile, straight line path in the Mission Hub with the cruise speed of 33mph...the estimate is 27min!

When it comes to drones it is always best to allow for plenty of breathing room, but rest assured that Litchi's ETA is more than one step ahead in that regard

 

[Kazzaaz]

Also you should check out Virtual Litchi Mission for planning your flights.
It has definitely saved my autonomous drone from hitting a cell tower once or twice on a hastily-made mission

 

[Deleted member 94047]

When it comes to drones it is always best to allow for plenty of breathing room, but rest assured that Litchi's ETA is more than one step ahead in that regard

That is comforting to know; my fear was it may be on the contrary and under estimate actual flight time. I think the Air does a maximum of 28km/h under P mode. I am at 1,800m asl; so I only get about 23-24km/h of speed. That is good enough for me though. The real limitting factor is the battery which at this altitude and temps gives me a flight time of about 12 minutes (landing at 20%). So considering both speed and battery limitations, I will be pretty conservative in my planning. I will not risk a long flight at least at the beginning.

I am aware of the VLM program, it is a nice tool. However, When I play the missions in google earth, I see no detail - forget trees and cell towers. I just see what I would otherwise see in google maps with the satellite view. Perhaps it is because there are no street-view type resolutions for google maps covering my area; or may be it is just that my connection is not ideal for things like this (1Mb/s isn't much of a band width). But I still get to see the camera orientation and such and that is great for planning. All in all, I like what I have seen thus far of litchi and VLM - Litchi's user interface is a bit jarring coming from the much more polished DJIGo, but I am sure I will get used to it.

Thanks again Kazz, you were a great help
.

 

[mavin]

After 6 months of flying the Mavic Air with DJI Go, I am jumping ship to Litchi. Just purchased the app and will be doing some experimental way points missions soon. One thing I can't really find info on is the duration of missions in the plan vs actual flight. If for example the mission plan says it will take 12 minutes for a mission to complete, how much more/less time will that be during actual flight? What is your experience?

Also, any other advice from experience will be greatly appreciated. Thanks!

I did my 1st 2 mission with Litchi
1st one reported to be 7 minutes, actual flight time was 12 min
2nd one, same WPs only adjusted for slower cruise speed, reported to be 9 min, actual flight time was 14 min

 

[Deleted member 94047]

I did my 1st 2 mission with Litchi
1st one reported to be 7 minutes, actual flight time was 12 min
2nd one, same WPs only adjusted for slower cruise speed, reported to be 9 min, actual flight time was 14 min

Thanks mavin. That has me slightly worried. Just finished setting up two test missions with ETAs of 6 and 7 minutes according to the mission hub. I will see how they go, as soon as the weather improves .

Also, if any one wants to have a look, my planned test missions are here

Test mission 1:Mission Hub - Litchi - simple circle of a tree at 7kph
Test mission 2: Mission Hub - Litchi - a more complicated one at 14kph

Edit: Apparently, it is not possible to share missions or I don't know how to do that
Edit 2: I made them public/discoverable and they should be accessible now.

 

[Bruce Lythe]

I ran an 8 minute Litchi mission in 9 mins 40 and then 20 minutes later same mission in 7 mins. Just a function of changeable Yorkshire (UK) coastal winds

 

[Kazzaaz]

I did my 1st 2 mission with Litchi
1st one reported to be 7 minutes, actual flight time was 12 min
2nd one, same WPs only adjusted for slower cruise speed, reported to be 9 min, actual flight time was 14 min

Any variance in time it takes to complete the mission is surely caused by the wind unless for some reason your drone isn't flying at the speed you set at the waypoint.
I have never had a mission take 5 minutes longer than predicted. Were you flying into headwind the entire way?

 

[Deleted member 94047]

Just an update: I run my test missions and the actual flight time was a little less than what litchi predicted; mirroring Kaz's experience. There was a little wind and I noticed the Air's speed was at times a little slower than the programmed speed. So I am bewildered as to how it managed to complete the missions in less time than what was predicted with a no wind scenario. All in all, pretty satisfied with the way things went. I am initiated in to Litchi, yay!