Hi guys, can somebody tell me which mode to use when I fly in the wood between trees? Atti mode or F mode - course lock? Thanks a lot. I try P -gps mode but I have not gps signal.

You can leave it in GPS mode and it will automatically go into ATTI when there is no GPS.
You use the F-Mode only only certain situations that you want to fly. If you want to freely fly around then use P or ATTI mode.
Most importantly, set the RTH to Hover so if you lose signal or get low on battery the aircraft will not ascend and hit a tree.

Thanks DJI-Ken. I see that you understand this modes much better that me because I have one more questions for you please. In which situations you suggest me to use ATTI MODE except when I lose gps. Except gps in which situation is better ATTI and in which situatuon is better course lock-F MODE . Thanks a lot!

michelii Posted at 2016-7-21 05:14
Thanks DJI-Ken. I see that you understand this modes much better that me because I have one more que ...

I suggest you learn to fly in ATTI mode in a very large field with plenty of wind.
The aircraft will remain level but it will drift with the wind. That way if you ever lose GPS signal and it goes into P-ATTI then you will know how to control the aircraft as you need to fly it.
As far as F-Mode, all the features are explained in the manual. You use those for whatever situations you want to use them.

Here is a video of learning to fly in A mode. Hope it helps:

Are you flying above trees, or between trees? Since you said no GPS, I assume you're flying between trees. That sounds a bit dangerous, since in ATTI, the drone will not be very steady and can drift around, you don't want it to crash into a tree.

In addition to what Ken said in #4, ATTI also allows you fly faster than P mode, some people find this feature useful in certain situations, for example, it starts raining, though it may drift around, including unsteady altitude.

I agree with Ken's comments about setting the RTH to Hover and learning to use ATTI mode with some wind. Flying in forests is quite tricky and I personally don't feel safe when the craft is switching between modes with poor GPS. That said, it is very important to plan your trajectory (look at it from different angles) and even use an assistant as a spotter, as very small branches & twigs can be a real problem. Next, trees have a surprise trick for eating Phantoms: fly beneath some lovely leafy branches and you'll be horrified to see how much the props pull things down (like flying a mini-quad indoors and discovering the first time that its sucked up to the ceiling). So start with a comfortable clearance.
Have fun & good flying!