I love the fact that I can set up flights on my pc and then upload them/edit them live using the app!  The videos now are so much smoother since I can control the speed and camera angle.

But before I get too crazy I wonder why don't they give us an option (or I may have missed it) to RTH,  if we lose RC contact?
I can see the advantage having it continue on, so I like having such an option, but it would be nice to also set it to RTH when loss of signal occurs.

I was also hoping that it would calculate the point at which it should not go forward and RTH when the battery power left can not make it back to Home on a straight line.  

Any opinions comments from the seasoned Litchi users?

I have to figure out why it is not taking pics at some select waypoints, which do not have any curving set??  Maybe it's because I have the auto record on?  It stops, waits, but no pics taken.

From what I read this is a limitation of the DJI API.  Looks like the software in the aircraft itself must complete a task that is transferred to it before anything else can be executed.   All other tasks must come from the "ground station" for which a valid connection is needed.

It sounds like this is a major issue, especially since so many are reporting RC signal loss.
To be safe then I will have to raise the battery critical level to about 40% to make sure I do not lose it, in cases where the potential RC signal loss is high.

I think the low battery is the only indicator which will initiate RTH, even when using the Litchi app.

But then, increasing the battery level defeats the whole purpose of using Litchi, which is to enjoy longer filght paths.

I am also curious; how accurate is the estimated time displayed in the Litchi app?
Is it based upon a pure mathematical calculation of total distance / speed?

Suggestion to DJI: Please consider an update, in which the P4 will warn if the downloaded flight from Litchi (or regular way-point) will exceed the battery life.

Suggestion to DJI: The P4 should also warn us during flight, once the direct distance from the bird to Home can not be covered by the actual battery level.

Join the club, Icarus! I'm a new litchi user myself. Yup been wondering about the same questions. There's actually a litchi group on google. You might want to check it out.

https://groups.google.com/forum/m/?hl=en#!forum/vctechplus

There is option for RTH ON LITCHI,
Settings, Signal lost option to RTH

Suggestions on the Litchi google group.

"As we've discussed on this thread already,  if you've set your critical battery level to 15% and  if you take no further action,  when battery reaches 15% the P3 will simply descend vertically and land, whatever is below it. However you can take action, if you've still got RC control. You can  attempt to manually fly it to a safer landing spot and so 15% will indeed give you a 5% margin, about 1min of flight time, over a 10% setting."

Please be aware of this, guys.

Hans

Post by a user on the group, by Albert D.

"After reading much discussion and speculation, I decided to do some real time testing with Way point and Orbit missions to verify exactly what happens at the end of missions when battery gets low..

The simple summary is that, with Return To Home set as the Failsafe action, at low battery the P3P will initiate RTH.

I set up two way point missions and also ran some orbit missions. (These were planned for all of the final portions to occur in an open field at 30-40 feet altitude, 200' to 500' from my observation point, with no obstructions.)

For the first mission, I set up and ran a 14 minute mission with the end of mission Finish Action specified as None. I ran this mission once normally to verify the flight paths, then flew back and landed. I ran the mission again with a fresh battery. About 10 minutes into the mission, I physically powered off my remote controller, to create a Loss of Signal condition. The mission continued to the end of the full 14 minute mission, then the P3P immediately initiated and successfully executed Return to Home, climbing to the 150 ft RTH altitude I had set, then returned and landed safely, about 5 feet from the take off position.

For the second mission, I added numerous circuits at the far end of the field, creating a mission that would take almost 25 minutes to complete (7-8 minutes past the expected battery endurance). I ran the mission with a fresh battery and again physically powered off my remote controller after about 10 minutes, to create a Loss of Signal condition. The mission continued until about 18 minutes, then the P3P executed RTH, returned to home point and landed safely. (Checking later, I had about 7% battery left.)

My third test mission was to run an orbit mission to end of battery. When battery power got low enough, the P3P initiated RTH (message: aircraft requesting return to home, will go home in 8-7-6... seconds). At the end of the countdown, the orbit stopped, the P3P climbed to RTH altitude, came to home point and landed safely (8% battery left). I was going to test orbit with loss of signal next, but I decided to do the following test to verify the RTH was happening based on when the vehicle calculated how much battery needed to go home, instead of low or critical battery warnings..

My final test mission was to send my P3P out, run a 3-row panorama (pano mode, mostly for fun and to run the battery down some), then start an orbit about 5000' from home point. Again, when the vehicle calculated it needed the remaining battery to come home, it initiated RTH (without any intervention from me). This time, RTH was initiated with almost 30 % battery (well above my low battery warning) and the P3P came to home point and landed safely. (I thought it said 8% when it landed, but when I re-checked the batteries after I got inside, it showed 6% left.)

From previous reports and discussion, I had expected the vehicle to operate each mission or orbit until critical battery, then land wherever it was. I was pleasantly surprised to see that, with the Failsafe mode set, the P3P safely brought itself home when it reached the RTH battery level, regardless of RC signal or Loss of Signal.

I am flying Phantom 3 Pro with latest firmware v1.6.0040 on aircraft and RC. Running the latest Litchi 2.7.1 on a Samsung Tab S2 9.7 32 GB LTE with Android 5.1.1"

That's great news, but that is not what is shown in the documentation I have for the Litchi app.
It works as I was hoping it would, based upon your empirical flight data above.  But when I read the Litchi manual, it is not referring to such RTH mode.

I will make sure I have the latest manual; if you have it, please offer a link.  I must have the latest litchi version, since I just purchased it.

MD_Icarus Posted at 2016-6-17 22:43
That's great news, but that is not what is shown in the documentation I have for the Litchi app.
It  ...

I'll keep an eye on that too as I will be using the app quite often as well. So far there's no change to the discussion.

By the way which os are you on? I'll try to keep you posted.

Maybe DJI can answer this:

Does the firmware automatically initiate RTH once it determines that the current battery level is about to be lower than the battery level required to bring the P4 back to Home?

As a discussion example,
if the P4 is a few miles out and the battery level is let's say 41%, but I need 40% to get back Home, will it initiate RTH at 40%,
even if the critical level is set to 15%?

MD_Icarus Posted at 2016-6-17 16:43
That's great news, but that is not what is shown in the documentation I have for the Litchi app.
It  ...

https://drive.google.com/file/d/0B9SCOsPRhNjTY2FfbDZJdi15S0E/view

malvern Posted at 2016-6-18 00:01
https://drive.google.com/file/d/0B9SCOsPRhNjTY2FfbDZJdi15S0E/view

Cheers Malvern