I know I'm new only 6 hours of flight time, but today I learned something new!  I normally fly in Florida, but today I was in the hill of East Tennessee.  I took off like always, a good rth locked in. I flew a mission and finally lost sight of the P4P, I hit rth and waited. As I watched the video feed I realized that my 30 m height return was not enough I'm headed for trees!

The system fixed the problem just before I could react and all was well, I then change rth height to 90 meters. Different terrains require different settings,  I have changed my preflight checklist to reflect this issue.

Again attention to detail is required.

Also compass should be calibrated any time you are 200 miles or more from your normal flight area.

My way of handling this (very important) issue is to set the RTH height to the maximum allowed (100-120m). This will save you from mishaps in most normal cases. Well, if you plan to fly through the skyline of a downtown, then RTH height will be the least of your concerns (swarming with people everywhere, great interference, lost signal due to buildings between your RC and the drone, etc.). So, I'd strongly suggest everyone to keep your drones out of crowded areas, including downtowns!! Luckily, mother nature has a lot to offer for breathtaking visuals!
Also, I always try to keep the drone within my line of sight. You will loose it once or twice, but better not make it a regular thing. RTH might be smart, but you never know what can happen (think of simple but important and non-predictable issues, like birds, etc.)

"The system fixed the problem".. So you are saying that it flew the route you flew back home, or it sensed and avoided collisions? Do you have any videos? I really want to see it in action!!

Good to hear you were able to make adjustments in time, sounds like luck was on your side.

Actually, the avoidance system saved me, it saw the tree and reacted faster than I did.  I sure appreciate the DJI engineers!

GreenHornet55 Posted at 2017-4-6 16:45
Actually, the avoidance system saved me, it saw the tree and reacted faster than I did.  I sure appreciate the DJI engineers!

Lol I bet you wore worried for a bit. Just wondering, how do you get your flight distance added below your forum name?

I don't know how the flight distance gets there, it showed up one day.

I'll upload the video when I get off the road, early next week.

FeariTself Posted at 2017-4-6 17:02
Lol I bet you wore worried for a bit. Just wondering, how do you get your flight distance added below your forum name?

I believe it obtains the information from the DJI cloud, where your details are updated when you sync your flight data.

But the flight distance displayed can be misleading. Firstly, does it display metric or imperial - or both (depending on where you are and what numbers are synced)? Secondly, DJI only knows about distance reported from flights using their GO app. If you use Litchi or whatever also, these distances aren't known so not taken into account in the figure displayed.

GreenHornet55 Posted at 2017-4-6 16:45
Actually, the avoidance system saved me, it saw the tree and reacted faster than I did.  I sure appreciate the DJI engineers!

Yeah, I agree  - it definitely does work.

I cut a video at a vineyard a few months ago, which included a fly-past of their function centre which was just out of sight to me. I was watching the screen while flying towards the building when the whole picture juddered, image jumped virtually sideways, and I briefly saw a 'collision avoidance activated' message on screen. I instinctively let go the sticks so my P4P came to a braked stop where it was. After I took a breath, I slowly spun the P4P around to work out what happened, and a massive flood light came into view, virtually taking up the screen - I'd missed seeing it on a tall pole as I was coming at it from it's side. Phew!

betonven Posted at 2017-4-5 17:09
My way of handling this (very important) issue is to set the RTH height to the maximum allowed (100-120m). This will save you from mishaps in most normal cases. Well, if you plan to fly through the skyline of a downtown, then RTH height will be the least of your concerns (swarming with people everywhere, great interference, lost signal due to buildings between your RC and the drone, etc.). So, I'd strongly suggest everyone to keep your drones out of crowded areas, including downtowns!! Luckily, mother nature has a lot to offer for breathtaking visuals!
Also, I always try to keep the drone within my line of sight. You will loose it once or twice, but better not make it a regular thing. RTH might be smart, but you never know what can happen (think of simple but important and non-predictable issues, like birds, etc.)

The problem with setting RTH to max allowed is the wind.  At 400 feet up, it could be quite strong and blowing the wrong way.  Best to set it as needed for flight location.
  

Kneepuck Posted at 2017-4-6 21:55
The problem with setting RTH to max allowed is the wind.  At 400 feet up, it could be quite strong and blowing the wrong way.  Best to set it as needed for flight location.

And also battery time.  If you are running low on battery, you do not want your drone climbing to 400 feet then having to descend that same 400 feet.  I agree with Kneepuck, you should set it to the height based on the need of the location.

Agreed. However, as still a newbie, I never fly with wind, while I also bring it close/down as soon as I start to hear the battery alert beeping at 30%, and spend another 15% just very near me.

In any case, as you said, this should be set as needed, but the 30m is  a not well thought threshold for the default.