Crash on a sailing sailboat

[rene strand]

My Mavic Mini Crashed after starting of my sailing 55 feet sailboat.

With a light breeze and only two knots of speed the conditions where great.

Soon after starting and flying the drone it starts to fly erratically right next to the boat (around 3 meters at the side of the boot and 2 meters above the water. I could not control it anymore.

Lucky the drone flew right in the boat and crashed in the cockpit without damage.

I ' afraid lounging the drone again from my boat. At land, it worked fine again.

Is there anybody in this forum who knows what possible went wrong?

Thx in advance !

René

 

[Fly Dawg]

Is there anybody in this forum who knows what possible went wrong?

This sounds like either wind issues or launching from a mettalicly compromized spot. We will need to see the flight logs to answer your question. Upload your .txt log to the link below and share a link back here:

DJI Flight Log Viewer | Phantom Help

We may also need the mobile .dat. Try the above first.

 

[deathmajor]

One thing to note is that the manual tells you to not launch from moving objects.

DO NOT takeoff from an moving surfice, such as a moving boat or vehicle.

The Vision System may not function properly when the aircraft is flying over water

 

[MacCool]

One thing to note is that the manual tells you to not launch from moving objects.

I wonder why not? I wonder if it's due to some problem with home point setting, or a handling issue, or if it's something that DJI's international lawyers said to put in the manual.

 

[sar104]

I wonder why not? I wonder if it's due to some problem with home point setting, or a handling issue, or if it's something that DJI's international lawyers said to put in the manual.

The main reason is that if you launch in P mode then the aircraft will immediately try to hold absolute position, not position relative to the moving object. That can lead to very undesirable consequences, as have been reported here a number of times.

 

[old man mavic]

or to put it simply the drone will hover above its take off point ,but where it was launched from will keep moving

 

[SqFt]

Im interested and concerned about this problem as well. I was hoping to get some sail footage of my own boat this summer with my M2 Pro. Ive seen people post vids of the Mavic doing hand launch and retrievals from boats. So it must be possible. I can see where the "Home" point would be an issue, as well as the vision system getting confused with a homogenous looking surface like calm water. I would think the wave action would give enough contrast and depth to focus on the water surface.

I would be hesitant if I was the OP after that incident. But maybe turning vision "off" and setting a manual Home point. Im pretty sure there is a setting for making the home point either near the remote control or a geo location. Best I can glean from the icon anyway. I read in another thread of someone suggesting launching from a point on land to avoid the moving launch point "vertigo". Thats a pain on a sailboat tho.

Edit: people answering as I was typing- Yeah, S mode would seem logical.

 

[old man mavic]

apart from the difficulty of launching a drone from a moving boat ,even if all went well,that compared to trying to land or hand catch the drone is the easy part
the idea of a shore launch would be ok if, the boat was close to the launch point and the person flying it stayed at that location and filmed it being sailed by someone else
what you have to remember is in the event of a problem, one mistake will result in possible damage to the drone,from either hitting the boat, or worse still ending up in the water and not being able to be found

 

[raymacke]

One of the reasons I bought the MM was to shoot video of my boat. But wondering now if I will ever get the nerve to actually attempt it.

 

[pmshop]

Edit: people answering as I was typing- Yeah, S mode would seem logical.

No, C, P or S will have the drone stationary at launch.
The best practice is to be ready for the differential in motion.
Launch then ihe instant the AC take off apply the appropriate direction to make it move forward with the boat.
IE launch facing forward on the bow, fly forward. Launch facing outward on the stern, fly backwards.

 

[MacCool]

One of the reasons I bought the MM was to shoot video of my boat. But wondering now if I will ever get the nerve to actually attempt it.

Well-placed concern if your boat is a sailboat. On my ski boat I can stop moving to launch or recover a drone. Sailboats represent a much more elaborate maneuvering process, not to mention a more cluttered landing zone.

 

[g36pilot]

Consider flying from a moving platform like instantly being in a formation flight. Mentally place yourself in the aircraft to grasp the concept (don't fly this way though unless FPV). If you do nothing the platform will move relative to the aircraft. You must constantly adjust to maintain formation.

 

[Dave Maine]

The easiest way to get great sailboat footage is from shore. Have another skipper sail by a land location while you buss around him. You will have plenty of time to compose shots, and execute some great moves quite safely.

 

[nlimchua]

My Mavic Mini Crashed after starting of my sailing 55 feet sailboat.

With a light breeze and only two knots of speed the conditions where great.

Soon after starting and flying the drone it starts to fly erratically right next to the boat (around 3 meters at the side of the boot and 2 meters above the water. I could not control it anymore.

Lucky the drone flew right in the boat and crashed in the cockpit without damage.

I ' afraid lounging the drone again from my boat. At land, it worked fine again.

Is there anybody in this forum who knows what possible went wrong?

Thx in advance !

René

I'd like to suggest this possibility: GPS satellite 'clock rollovers' - the Russian Glonass (which newer DJI A/C use; P3 and up) sat network is due for this crossing into early Jan 2020.

GoPro Karma drones grounded worldwide, thanks to possible GPS glitch

The drone hasn’t had a software update since late 2018.

www.theverge.com

 

[droneofarc]

My Mavic Mini Crashed after starting of my sailing 55 feet sailboat.

With a light breeze and only two knots of speed the conditions where great.

Soon after starting and flying the drone it starts to fly erratically right next to the boat (around 3 meters at the side of the boot and 2 meters above the water. I could not control it anymore.

Lucky the drone flew right in the boat and crashed in the cockpit without damage.

I ' afraid lounging the drone again from my boat. At land, it worked fine again.

Is there anybody in this forum who knows what possible went wrong?

Thx in advance !

René

I believe the wind is the major impact on the flight, especially where there is water. I think DJI did not do enough studies to see that this would be a issue.

 

[netsonic]

Soon after starting and flying the drone it starts to fly erratically right next to the boat (around 3 meters at the side of the boot and 2 meters above the water. I could not control it anymore.

The cause is flying close over water, without turning off or better said disabling (covering up) VPS. The IR leds are keeping altitude (height) but the video camera is stabilizing lateral movements. As soon as you took off with enabled VPS, it tried to hold position or stabilize and failed as expected. You got lucky and crashed into the boat.

One of the reasons I bought the MM was to shoot video of my boat. But wondering now if I will ever get the nerve to actually attempt it.

Please read above how VPS works.

In a Nutshell:
Covering the downward looking sensors will allow you to control better the movements or flight over water. Pay attention as it comes with the risk, that you will not have any fail safe preventing you to safely descend and the AC sensing that it's close to the water/ground.

 

[atsphenomenon]

There's a tethering mode in litchi that lets you use one additional phone as a virtual tether. This should work well on a sailboat once the SDK comes out. I presume landing it would need some expertise.

 

[Wild Wayne]

Soon after starting and flying the drone it starts to fly erratically right next to the boat (around 3 meters at the side of the boot and 2 meters above the water. I could not control it anymore.


Is there anybody in this forum who knows what possible went wrong?

Thx in advance !

René

I’m new to drone flying but am a life long sailor. By your description… It sounds like you were flying in the boats ‘wind shadow’. Also called dirty air. A 55’ sailboat even in lite air will create lots of turbulence. I race a 26‘ Thunderbird (3,600 lbs). If I got stuck behind you it would toss me around like a cork. Best thing to do is tack and get away.

so many questions... Who is the boat maker? Were you under sail? Did you have the main and the headsail up? That’s a lot of surface area! Where you flying the drone on the windward or leeward side?

 

[jamesfrankham]

I have done a lot of launching and landing from boats at sea. It can be done safely and effectively but needs a lot of practice and depends entirely on conditions.

Basically it’s a fully manual proposition—you can’t use home point and you’re active on the sticks the moment after lift off. Second, every launch and landing is from the hands, with all of the risks that entails, including obstacle avoidance and landing protection where the drone will actively avoid capture.

Generally the pilot cannot be the same person catching. You therefore need a lot of communication between the skipper, the pilot and the catcher—calling wind puffs as well as calling the countdown for the catch. Often the pilot will need to hover at a safe distance from the boat for seconds or minutes until the conditions are right to approach and catch.

The deck of the boat must be cleared of equipment, and booms on yachts swung clear allowing the largest possible landing zone for the pilot. You must also allow extra battery for the landing process—coming in hot and low not an option.

It is not for the faint hearted and must be conducted with military precision in good conditions, but we have safely launched and retrieved everything from Minis to fully loaded Matrices with big payloads. Not for new pilots, and landing protection appears to be impossible to disable on a Mini.

Practice, patience and perseverance required. Safety of crew and vessel is the priority, the drone itself very much a low priority.

 

[Pieter Einthoven]

I have flown my MPP from sailboats several times. No experience with the MM, but I assume it is similar. There is a bunch of settings that are very important, such as turning off maximum distance and updating home points (see link below). Also, when you power up your drone on a moving boat it might take longer to get a gps fix, but if you don't wait for the GPS fix, your drone won't fly as well. I would not recalibrate inertial sensors while moving. Always launch from the back of the boat. The drone will immediately go to a hover and separate from the boat. Automatic altitude control is flaky but seemed to settle down after flying for a while. I do not cover the down sensors.

For recovery I mount a handle on the bottom, making it MUCH easier to recover the drone. Not sure that the MM can carry the weight of the handle, but the MPP does fine. As someone else suggested, have someone dedicated to catching who is not flying the drone or manning the boat. When I get close to the back of the boat, I turn the drone and fly backwards to the back of the boat so the obstacle sensors done freak out. Once the drone is on board, turning it sideways usually turns off the power.

This thread has some good info on settings and info on my hand catching mount

Who here wants to fly from a boat but doesn't want to lose their drone?

Now I can't guarantee that you won't lose your drone.... but in this video, I outline a few of the precautions I take whenever I fly a drone from a boat. I have learned a few of these lessons the hard way so why not learn from my mistakes. https://youtu.be/kAHL5rdcnno Thanks for check out the...

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