Phantom Vision LOST :(( RTH didnt work(??)

phynesse · Sep 13, 2014

so i just flew around a cruise ship that was sitting in the harbour nearby. i was flying at roughly 30m height, paning around the ship slowly. when i was almost round the far end FPV cut out which is nothing too unusual with the v1 Vision. Telemetry was still fine, so i kept going the last bit, since i was already very close to turning homewards. it was below 300m distance which i had flown before several times.
Then RC lost signal too.
i anxiously stared at the sky, expecting the Phantom to appear on its way home, but it didnt. after 3min i started running towards the ship which was quite a way - i was on a hill about 70m away, 20m high.

after about 7min i made it to the ship, so there should have been some battery left, but i couldnt get a view of the ship's backside obviously. even the front area was gated, i couldnt even get close and peek around.
i kept restarting the app, and setting S1 to RTH (as configured in software). but never regained signal.

So since i never saw the copter emerge again i must assume it never left the far side of the ship. its also the last logged position in Find my Vision function, but thats obvious. Either it fell in the water, or tried RTH and crashed into ship, which is a scary thought.

Here is my question: the ships height was definitely 20m+, but my starting point was at least 20m high to begin with. Does the 20m/66 feet clearance height for RTH count from starting position or absolute?

Then there are also all these big antennas on the back of the ship, so who knows what was going on there..

argh, not nice at all.....

andrewket2 · Sep 13, 2014

If you got close to the ship's radar antennas, that may be the cause of your LOS and could even cause electromagnetic interference to the point of downing the bird. I have personally witnessed small electronics failing in strong RF areas.

Noël · Sep 13, 2014

I guess that it crashed into something trying to get back home (straight line).
It might have crashed on the ship, so try to get in contact with the captain, and ask if they found your Phantom.

rrmccabe · Sep 13, 2014

So I assume your 30m may be lower than the highest point of the ship?
If so, you fly around back of ship, it loses line of site, sits there for a minute and then heads for home. If you were lower than something on ship and it was in its way on RTH then you ran into it.

darwin-t · Sep 13, 2014

If it is less that 60 feet up, it goes up to 60 feet and comes home. If it is above 60 feet up, it remains at that altitude and comes home.

Onezerosix141 · Sep 14, 2014

Flying around huge hunk of metal sounds pretty risky.
I think it must of tried getting home & got stuck. Checked the deck if the ship?

phynesse · Sep 15, 2014

At the time I had decided not to try getting onto the ship. We are talking huge cruise ship here, so i couldn't just walk on.
Meanwhile i have contacted the shipping company but havent heard back. I m not holding my breath.
Instead i ve started shopping for replacement. Breaking/losing something is always best excuse to upgrade.
But i also believe it simply hit the shop on RTH. So that is really the big lesson here - never*ever fly behind anything that's taller than 20m..

Buckaye · Sep 15, 2014

Sorry about the loss... That sucks... But still, my understanding of RTH is that it would keep the last altitude if above 60 ft... So I guess I would say that you try to keep the altitude as high as possible for tricky flights like that.

ProfessorStein · Sep 15, 2014

RTH height is in relation to the home point, yes. So, if your starting location was 20m above MSL, your Phantom would've tried to rise to 40m MSL if it wasn't already higher than that. And if it was already higher, as others have said, it would've maintained that height as it headed for home.

And, as has been said earlier, I'd reckon your VX and TX loss were due to the structure and materials of the ship, and/or the ship's onboard navigation and communication electronics.

But... I'm curious... have you considered that your Phantom was intentionally downed? Not that I'm a conspiracy theorist or anything... but if you're around the back of the ship, it seems it wouldn't have taken much more than someone throwing a towel at it, or some other object, sending it into the drink. Don't know how far away from the ship you actually were.

rrmccabe · Sep 15, 2014

phynesse said:
. So that is really the big lesson here - never*ever fly behind anything that's taller than 20m..

This is how we learn for sure.

Just always assume that you can lose connectivity at any time when you are at a distance.

As mentioned previously, you might consider raising bird up in the air a couple hundred feet and resetting home so it if does try to RTH it will raise up very high first. You have a good chance of regaining control quickly with this method too. So as long as "up" is clear.

OI Photography · Sep 15, 2014

ProfessorStein said:
But... I'm curious... have you considered that your Phantom was intentionally downed? Not that I'm a conspiracy theorist or anything... but if you're around the back of the ship, it seems it wouldn't have taken much more than someone throwing a towel at it, or some other object, sending it into the drink. Don't know how far away from the ship you actually were.

I've only been on a cruise once, but I remember one of things I enjoyed the most was skeet shooting off the back deck