Hi,

I am going on a boat-race this summer with rather big wooden sailships (actually this one). The race consists of a fleet of approx. 40 ships. I really want to capture some of the moments during the race with my new Mavic Pro. Hence I need to intensify my practicing (new to using drones). I have a couple of questions in this regard

1. Which app should I be looking at? I am rather technical of nature and have been glancing at Autopilot, Litchi and DJI Go 4 of course.
2. Is it possible to land on a moving ship like these when the speed is expected to reach a maximum of 15 km/h? If so then how? I can easily hand release and land when standing still, but I expect it to be quite complicated when the boat moves. Does anybody have experience in this?

you are going to get a whole bag of mixed response's most of which will probably say its not worth the $$$ to lose your drone. but if that is what you have bought it for and you want to give it a shot, be aware of all the risk's.

The problem is Mavic' GPS is "too smart" for its own good.

For example say you took your Mavic on a large cruise ship (I know they are banned on ships) and you launch it from your stateroom.
The ship is going at 20 knots, and there is no wind in your stateroom, so Mavic should just float, but instead it will try to "GPS" hover and stay in place, which means it will smash into the wall.
Same problem when trying to land your Mavic back onto a moving object of any sort. immediately before it lands, it will "hover" before cutoff, which means that if the platform is moving, it will go the opposite direction.


Unless there is an app out there that can specifically land on moving objects as part of its smart mode, I think you are out of luck.

If you can get a large enough net, you could in theory fly your Mavic over it, and then do a CSC when its close in range.

Sbbunno Posted at 2017-5-22 00:52
you are going to get a whole bag of mixed response's most of which will probably say its not worth the $$$ to lose your drone. but if that is what you have bought it for and you want to give it a shot, be aware of all the risk's.

Sorry i pressed enter and it posted instead of starting a new paragraph...

a few helpful tips.

1. i Use DJI GO4 (personal choice_
2. Taking off and landing, im not sure on the technicalities as this is off the top of my head, but i believe taking off from a boat my cause issues with the compass due to instability and metal.
3. "Return to Home" - change that setting to "Hover" and have a solid plan on retrieving the aircraft is something was to go wrong.
4. the speed will be determined by the method you use and the skill you have, in Active track i believe the top speed is approx 55km/hr and he drone will just follow you if set correctly. In sports mode you are more hands on as the pilot but can reach (at least i do) 70 km/hr on a good condition day.
5. Landing!!! this is the biggest danger for yourself, crew and boat. this ultimatley depends on whether you want to risk it or not and your skill. yes it enters into hover mode as it lands but you can control its direction... would only recommend if you  are at near standstill with a drift.

I have been flying Rc aircraft long before drones became main stream and this is the sort of stuff i have it for. so i understand the desire, but you must weight up the risk and consequence. if your happy with it give it a go, just please be careful.

  - A link to a dive video where i filmed the boat, all the crew where well clear when takeoff and landing.

Hope this helps. again its off the top of my head sorry if i missed a lot lol good luck

one more.. sry

OK, so you were able to fly it under water to get the shot of that sweetlip. Sweet!!!

On the serious side, I'm planning to do a lot of flying from a private yacht - a 20 t steel boat - during this summer. I am not concerned with RTH landing, as I normally hand catch it anyway, and doing so is no problem if you just are not stressed and have plenty of battery left just in case. I am rather concerned about the Compass being seriously misled by all the steel.

Anyone having more experiences?

M

I have flown off a boat on many occasions, hand launch and recover each time. I think the difference is going to be whether the ship is standing still or moving when it comes time to land (much easier to hand catch if it's just hovering vs moving forward at X speed). Also would recommend one pilot, and one catcher.

On one occasion, we lost signal and the drone initiated a RTH, which since we were in a small boat, we were easily able to turn around and chase it down until we were back in range. Not possible on a boat race or cruise ship, which is what those scenarios are a bit riskier.

I have launched mine several times off a 44' Sailing Cat. Always take off from the back. Hand launch or deck make sure when it lifts up there is nothing it can hit when it goes up and back.
  I def agree to use a second person as a catcher, I use my 13 YO son. Easy enough to catch but we do return early to ensure we have plenty of battery life to do go around son missed approaches.  

Winds and speed of the boat are big factors and wouldn't recommend launching in "sporty" conditions.

All my flights are short and ideal for the drone. Even better when at anchor

eMaX Posted at 2017-5-22 09:49
OK, so you were able to fly it under water to get the shot of that sweetlip. Sweet!!!

On the serious side, I'm planning to do a lot of flying from a private yacht - a 20 t steel boat - during this summer. I am not concerned with RTH landing, as I normally hand catch it anyway, and doing so is no problem if you just are not stressed and have plenty of battery left just in case. I am rather concerned about the Compass being seriously misled by all the steel.

I'm assuming you understand I was referring to the end, the fish is called a Harlequin over here in Aus .

i am personally more nervouse about catching the drone by hand with its low clearance, i prefer to land on the Esky, or cooler for the americans? i feel it is safer, but again my opinion.

Great to hear some experience. What I hear is full manual (No active Tracking or anything enabled) landing with a friend catching it is possible (without putting the Mavic into landing mode, but 'force' catch and descend while moving).

Precautions about speed, metal, wind etc. of course have to be taken into account. Any good suggestions on how to practice this on land?

Just practice catching in general. It needs to happen kinda fast because the sensor will move the acft once it sees your hand. Once grabbed it will fight to take off again until shutdown. It's pretty easy though. Just pick the right conditions and you will be fine.

eMaX Posted at 2017-5-22 09:49
OK, so you were able to fly it under water to get the shot of that sweetlip. Sweet!!!

On the serious side, I'm planning to do a lot of flying from a private yacht - a 20 t steel boat - during this summer. I am not concerned with RTH landing, as I normally hand catch it anyway, and doing so is no problem if you just are not stressed and have plenty of battery left just in case. I am rather concerned about the Compass being seriously misled by all the steel.

Why not use activetrack, then set the RC as home?

Here is the correct answer.. DONT DO IT.  Done it. crashed!

To take off a moving platform, be it cruise ship , boat whatever, you need all sensors off and to be in full atti mode.
The mavic is the worst for this kind of mission.

1 - it has no landing gear to easily grab, while the quad is tilted to keep up with the speed of ship
2- you can't  actively turn off gps. ie activate ATTI mode manually.

From experience I was on a cruise ship.. it slowed to 10kts.. about 20klmh.. I was out on an open area .
Attempted take off as soon as it did pitched in the opposite direction of the ship and flew straight into a window.
Lucky the battery came lose when it crashed and cut power to blades.

Like Air crash investigations, after replaying the events, it made perfect sense.

The mavic, when it takes off, wants to lift and hover in the same spot determined by gps.
The ship is moving so the mavic is effectively travelling at 20klms per hour before props start.

As soon as it starts and lifts off the mavic registers that it is traveling at 20klm/h and tries to hit the breaks to hover as its suppose to.
it does so correctly as it suppose to but the ship keeps moving around it. so the Mavic will stop in its marked gps spot until in my case it
hit the window.
Unless you are quick to correct and push forward on the sticks you will be caught off guard.
Either way its not a good idea.

So to launch of a ship the best place is off the back. so when you take off it will hover over the water while the ship moves forward and away.
at that point you would then need to chase the ship, and make sure the home point is not set. because if the drone gets too far or u run low on batteries
it will go back to the middle of the ocean where u launched from.
Again not a good idea to launch off a moving ship.

Im glad mine crashed into the window because if I did manage to lift off after not considering the gps effects I would have had a bad experience trying to (crash) land.
I would have had to chase the ship and then try to hand land the quad. With downward sensors on and a tilt angle to match the speed of boat I recon I would have
lost a finger or 2.

so moral of the story is don't do it on a cruise ship while its moving! firstly its not allowed and the mavic has to much automation to allow this to be done safely.

One last thing if forgot to mention, the ship
is all made of steel. Metal screws with the compass.. I had compass error that was coming and going..
I had a moment of bad judgement focused on the picture moment and not my safety, i did the take off and luckily it crashed softly.
Luck was on my side and I walked away with a broken prop.  
Big lesson learnt that day
So my advise to you all, if you want to launch of a moving ship.. DONT DO IT!

There are too many variables working against you when taking off.. and if you do good luck trying to land it again..
If you don't crash trying to land and don't lose fingers... go play the lottery cause you are the luckiest person on earth!

adiru Posted at 2017-5-22 00:56
The problem is Mavic' GPS is "too smart" for its own good.

For example say you took your Mavic on a large cruise ship (I know they are banned on ships) and you launch it from your stateroom.

Yup, sadly I have to confirm that- disabling the sensors would not help much, tapping sensors would not ether, gps is the issue. Mavic 3, Avata 2 etc would land reliably only if complete stop of the ship. I managed to destroy a Mavic 3 on sketchy landing on the aft number 7, it was eminent. Ironically the only landing that worked semi smoothly was during the night, I have no idea why. FPV drones with BMPCC 4K and GoPro saved my day, sort of - ships don’t look very good when horizon is tilted most of the time:/ The Inspire series has dynamic home position mode but I have no experience with those drones and I don’t know if that feature will help during landing or catching on a ship in motion. At this point I am thinking about strapping barebones Mavic 3 onto large FPV quad and run a two persons operation.