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What about home point when flying from a boat?

ash2020

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Hi all.
The time is approaching when I must try flying from my boat. I've been practising catching and I've got styrofoam balls :)
I need to think hard about RTH settings. Is the best way just to keep on changing the home point so if it all goes pear shaped at least it won't be very far away?
Thanks.
 

Lake_Flyer

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Set RTH to hover.
I would keep it close enough (within 200 meters) to be able to get to your drone in time when it is hovering with a low battery. Set the low battery warning threshold 10% higher so you have more time once the warning sounds. But never let it come to that. Bring it in before you reach the threshold.

Dynamic home point is not reliable enough. It relies on the GPS of your phone, which is not always correct and never intended to be a drone saver.
 
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ash2020

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Set RTH to hover.
I would keep it close enough (within 200 meters) to be able to get to your drone in time when it is hovering with a low battery. Set the low battery warning threshold 10% higher so you have more time once the warning sounds. But never let it come to that. Bring it in before you reach the threshold.

Dynamic home point is not reliable enough. It relies on the GPS of your phone, which is not always correct and never intended to be a drone saver.
You're right, hover would be the best setting. I guess i just need to get it out of my system, do a couple of circuits around the boat, take some video, then I probably won't do it much after that. I did some kite aerial shots a few years ago, but it was frustrating because, when you're sailing, the kite's always behind you so you never get a picture of the front of the boat!
The other issue is that there are lots of things to hit, rigging, sails, boom etc. and ideally I would want to stop the boat before landing, which would be easier with the sails down, so lots of time needed.
Thanks.
 
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Lake_Flyer

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You're right, hover would be the best setting. I guess i just need to get it out of my system, do a couple of circuits around the boat, take some video, then I probably won't do it much after that. I did some kite aerial shots a few years ago, but it was frustrating because, when you're sailing, the kite's always behind you so you never get a picture of the front of the boat!
The other issue is that there are lots of things to hit, rigging, sails, boom etc. and ideally I would want to stop the boat before landing, which would be easier with the sails down, so lots of time needed.
Thanks.
Ah, a sail boat! That's more challenging indeed.
I fly from a console boat when I fly over water. I have a 33ft sail yacht but haven't flown my mavic from that yet because of the very things you say. I usually sail it just by myself, I have no extra (experienced enough) crew at hand that could help lowering the sails and keep the bow in the wind while I would retrieve and hand catch my drone.

Better take at least 5 minutes extra for final and catching. The Pro has enough battery time for shooting the boat and getting it back without too much of a hurry. But the Air doesn't leave a lot of time to mess with. I don't know which one you have.

I would turn off all stuff that consumes extra power like obstacle avoidance and downward sensors. You can't use that on a boat anyway. Switch off Landing protection as well so catching, even grabbing, is easy without it spinning up full speed trying to escape your grip. Try hand catching this way on dry land first a couple of times. Better have someone extra to catch it while you control the drone, practice this as a team.
 

Lake_Flyer

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Do you have any pictures of your boat?
Here's my old Maxi 95,P1000274.jpg I would love to shoot it while under full sail.
 

ash2020

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Ah, a sail boat! That's more challenging indeed.
I fly from a console boat when I fly over water. I have a 33ft sail yacht but haven't flown my mavic from that yet because of the very things you say. I usually sail it just by myself, I have no extra (experienced enough) crew at hand that could help lowering the sails and keep the bow in the wind while I would retrieve and hand catch my drone.

Better take at least 5 minutes extra for final and catching. The Pro has enough battery time for shooting the boat and getting it back without too much of a hurry. But the Air doesn't leave a lot of time to mess with. I don't know which one you have.

I would turn off all stuff that consumes extra power like obstacle avoidance and downward sensors. You can't use that on a boat anyway. Switch off Landing protection as well so catching, even grabbing, is easy without it spinning up full speed trying to escape your grip. Try hand catching this way on dry land first a couple of times. Better have someone extra to catch it while you control the drone, practice this as a team.
I have an Air, so I'm aware of the time pressure! I've looked carefully at the boat and it's quite difficult so see where I could drop it on the deck. I'm planning to heave to, so the foresail will be near the centre line, making the foredeck unusable, also, its a 130% overlapping Genoa so very little space up the sharp end. She has quite a deep, narrow cockpit, with quite high guardrails. The backstay splits from about 10' up down to each corner so really I figure the only option is to bring it close to the sdie and hand catch it. The videos I've seen are usually on fairly beamy yachts with lots of space in the cockpit and generally 3 or 4 people to help. Given that there will only be 2 of us and I want to get some shots under full sail, then heave to and land the Mavic, it's going to be a challenge. That's why I've decided to use floats and a handle underneath, although it will impact on flight time. I'll probably just do one circuit then finish.
Cheers
IMG_6724.jpg
 

gnirtS

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Set signal loss to "hover".
Ditch the polystyrene balls - they'll do nothing to protect the drone but will make it harder to cope in wind and will use more battery.
Hand launch and hand recover from a stationary (as best as possible) boat.
 

ash2020

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Do you have any pictures of your boat?
Here's my old Maxi 95,View attachment 43850 I would love to shoot it while under full sail.
Lovely boat. You would have the same issues with the backstay.
The reason I want these shots is because I'm making a video about some tests we're doing, comparing a junk rigged boat and my Bermudan rigged boat. The junk rig is amazing - no rigging! No forestay or backstay or side standing rigging! A dream to sail.
Mine is a Varne 27. I think people who don't sail underestimate the problems involved in launching and catching a drone in a swell!
Cheers
_DSC4943.jpg
 

ash2020

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Set signal loss to "hover".
Ditch the polystyrene balls - they'll do nothing to protect the drone but will make it harder to cope in wind and will use more battery.
Hand launch and hand recover from a stationary (as best as possible) boat.
The only reason for the polystyrene balls is to recover it if it dunks, for the replacement program (not DJI). I don't envisage the boat being stationary. It won't be moving horizontally, but it will be going up and down. What would you advise to make sure I can retrieve it if it drowns?
 

gnirtS

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Even prop spray can force enough water into the drone to kill it. If its salt water its dead instantly.
There's no point getting back a dead drone unless you have refresh.
All the balls do is make it MORE likely to crash by upsetting the balance, handling and battery usage.

up and down is fine but you absolutely must hand catch it.
 

Lake_Flyer

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Even prop spray can force enough water into the drone to kill it. If its salt water its dead instantly.
There's no point getting back a dead drone unless you have refresh.
All the balls do is make it MORE likely to crash by upsetting the balance, handling and battery usage.

up and down is fine but you absolutely must hand catch it.
I agree with that the balls could make it unstable in flight, specially with winds, enough to make that sloop heel a bit, which is what you would like. But I have great flying and floating results with self made float tubes (from pool noodles) on fresh (!) water. Never had a drop on the lens or on the drone while landing and taking off from (even quite choppy) water. But I would never land on salt water, the risk is not worth it.

Hand catching is surely the best option.

A mavic destroyed by salt water is usually a total loss.
 

Lake_Flyer

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Lovely boat. You would have the same issues with the backstay.
The reason I want these shots is because I'm making a video about some tests we're doing, comparing a junk rigged boat and my Bermudan rigged boat. The junk rig is amazing - no rigging! No forestay or backstay or side standing rigging! A dream to sail.
Mine is a Varne 27. I think people who don't sail underestimate the problems involved in launching and catching a drone in a swell!
Cheers
View attachment 43853
Another lovely classic sloop! They don't make them anymore like that. My Maxi is from '76. Reminder of the best of all times, if only for the music and the girls.
 

ash2020

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I agree with that the balls could make it unstable in flight, specially with winds, enough to make that sloop heel a bit, which is what you would like. But I have great flying and floating results with self made float tubes (from pool noodles) on fresh (!) water. Never had a drop on the lens or on the drone while landing and taking off from (even quite choppy) water. But I would never land on salt water, the risk is not worth it.

Hand catching is surely the best option.

A mavic destroyed by salt water is usually a total loss.
I agree, salt water will kill it. Sorry if I wasn't clear. The balls were never intended for landing, only emergency recovery of the dead Mavic. I have a replacement insurance from the supplier, Heliguy, which covers immersion in saltwater. I'm certainly not planning a swim, but as a last resort, I need to recover it.
There used to be a brilliant gadget called WaterBuoy which was a keyring thing that inflated a ballon and allegedly would lift 1Kg but they stopped trading. I do have one but I wouldn't trust it as its a few years old.
 

newt2u

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vlcsnap-2018-08-19-17h09m01s150.png

Have also been thinking about getting some videos while sailing. This is a still from a vid taken from the beach (the boat is a Coaster 33 - 1979). To get some decent sailing pics/vids you need some wind but not too much to fly the drone and this is another problem. I also have a MA and have been considering landing options. One thought I had was to construct a landing platform on my tender and land on that while its being towed astern. I also do not have experienced deck hands so the plan is to sail on auto pilot, fly MA, take the vid, come into wind and land on the tender.

btw, the video this was taken from can be found here:

 

ash2020

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View attachment 43861

Have also been thinking about getting some videos while sailing. This is a still from a vid taken from the beach (the boat is a Coaster 33 - 1979). To get some decent sailing pics/vids you need some wind but not too much to fly the drone and this is another problem. I also have a MA and have been considering landing options. One thought I had was to construct a landing platform on my tender and land on that while its being towed astern. I also do not have experienced deck hands so the plan is to sail on auto pilot, fly MA, take the vid, come into wind and land on the tender.

btw, the video this was taken from can be found here:

Lovely video, thanks. Nice boat too! Tender is a good idea, apart from the fact that it'll be in all the shots, but a minimal downside. Do you have enough space in the cockpit to lay out a landing pad?
I was going to use the Autohelm too, although my partner Maggie might be OK on the tiller if its not too choppy. As you say, the wind has to be just right. We've got 5 knots forecast for tomorrow, which might be enough to fill the sails. Wouldn't it be awesome to get the spinnaker up too?
I might have some nice video by Tuesday, but I might be minus a drone! Wish me luck.
 

newt2u

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5knts is probably about right for a first attempt, I wish you all the best. Don’t forget to post your vid... assuming you recover the MA :cool:

My cockpit is enclosed on 3 sides, see: Coaster 33 for info, so no chance of landing there. I have the same problem with the genoa, which is about 130% so it does not leave much room.

I won’t be sailing again until later in the week but Ikm not ready to try it yet.
 

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IF you try to land the mavic at 5kts you're going to need a new mavic...!
 

newt2u

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I think the plan is to head up to wind and kill the boat speed before landing, otherwise you would be right.
 

gnirtS

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Hand catch it. Don't try to "land" it. Even the slight bounce of hell or drifting will make it likely to hit something.