I read a post in a German forum where a P4 pilot lost his drone just yesterday.

  

Connection was lost and he triggered RTH (set to RC). Unfortunately, he was on a boat and it ended as we all think it did.

The P4 went for a dive just a few meters near the boat. The guy was never able to re-establish connection so he couldn't stop the RTH process.

  

Is there no option to have the drone return to home point (set to RC) and not land but hover at x-height above home point??

Can't find such a setting...

  

Unfortunately there is no setting, but it's a worthwhile suggestion.

There is a dynamic home point option where it will set the home point based on the mobile device's position, however, the device needs to have a GPS module built in for it to work.

DJI-Jamie Posted at 2017-3-17 16:46
There is a dynamic home point option where it will set the home point based on the mobile device's position, however, the device needs to have a GPS module built in for it to work.

That wouldn't have changed the outcome in this case.
And it's not dynamic.
A dynamic home point is one which continually updates to keep track of a moving home point like the P2V+ could do.
That feature was dropped in the P3 & P4 series and all that's possible is to reset the home point to the current location of the controller - which is hardly dynamic.

It's a confusing OP.  If connection was lost, how did the pilot trigger RTH?  Maybe he means the lost connection triggered fail-safe which was set to RTH?  

Also, it sounds like the pilot didn't know how to cancel RTH, so the AC seemed to never regain the signal.

Couldn't the pilot have set the fail-safe to hover rather than RTH?  Presumably that would have kept the AC out of the drink long enough to get under it.  

"If connection was lost, how did the pilot trigger RTH? "
"Also, it sounds like the pilot didn't know how to cancel RTH"
  

The guy was on boat near Koh Phi Phi Island in Thailand.

  

Drone was 500m! high and 300m away when connection was lost.

Tapping on RTH in the app didn't show any result so he triggered RTH on the RC which brought the drone back.

It's being suspected he only THOUGHT that he initiated the RTH sequence not knowing the P4 was already in failsafe  mode on its way back.

(The other guys were also wondering how he triggered RTH while having no connection.)

The drone was out of sight when the incident occurred and image transfer has aborted.

It's being suggested that a jammer device might be the cause. Apparently lots of resorts in Thailand have anti-drone jammers.   

The boat operators told him they have seen other guys losing their drones. Drones are not welcome in the area.

The guy was able to dive for the drone and recover it.

People are suggesting trying to investigate flight data stored in the AC.

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