Awesome tutorial. much better than learning via trial and error! Thanks for taking the time to explain this as we boat in super high winds here in the San Francisco Bay where the winds routinely blows 20-35 knots every afternoon during spring and summer months and there is always a stiff cross wind when docking
The idea of using the downwind engine while turning the rudder towards that side is sound. A suggested improvement in your presentation is as follows: the force vectors cannot arbitrarily be relocated to the center of mass of the boat. Those force vectors act at the location of the forces. Thus, the sideways rudder force pushes the boat in the upwind direction as shown, but since the force is applied at the location of the rudders it also provides a turning moment that rotates the bows downwind. Similarly for the wind force that acts predominantly on the bows - it provides a side force as well as a turning moment that rotates the bows downwind. The offset engine thrust is the only force that opposes both of these rotations. The rudders provide the only adjustable control of lateral force, and the engine provides the only adjustable control of rotation. So the right way to think about the helmsman's job is to use the rudders to adjust lateral position, and the throttle to adjust rotation. It's important to remember that the rudder forces will be affected by the engine thrust if they are in the wake of the props (this will be a factor either in forward or reverse depending on rudder location). Also, the rudder force depends on the square of the boat speed, with zero force at zero speed (neglecting prop wash if applicable) so it's essential to get the boat moving for the rudders to work at all. I hope that all makes sense...
Thank you for your comments. The forces are not arbitrarily moved to the CG, the effect of a force at any point not at the CG - of more accurately the biased mean between CG, Aerodynamic Centre (windage) and Hydrodynamic Centre (current effects), which varies from boat to boat - will always create a force and a turning moment. The sum of these moments and vectors acts on the CG with the caveat already mentioned… so they are moved there to represent in a simpler way what happens to the vessel… nothing arbitrary about it, just mathematics.
Excellent video, thank you very much. There are catamarans that have the propellers behind the rudders. So the propellers don't stream the rudders (in forward motion). That means there is only rudder action when the boat is moving. I guess this technique doesn't work then, does it?
I love this technique and memorized it but only now realize things are different on a lagoon. Can you explain what is different ? Greatly appreciated!!
For this manoeuvre the Lagoon behaves the same - it is the displacement of thrust and drag that causes the lateral drift… however, for moving sideways off the dock you need to use a different technique than with other cats - this is discussed here czcams.com/video/5OMAuIHdHKc/video.html
Awesome video. I am new to cats this year. We will be sailing an FP 36 Mahe next season. The props are aft of the rudders. I would use the “lagoon video” technique when leaving the dock however, I am guessing the docking procedure stern to wouldn’t change? Am I understanding that correctly?
I really appreciate this, and your going forwards guide is great. But why does the rudder have the same impact going backwards as forwards? Going forwards you get the prop thrust over the rudder, whereas going backwards you only have the slow speed of the boat through the water which is substantially less.
You are, of course, absolutely correct. More speed is needed going aft to have the same effect, but it works predictably and consistently. On some catamarans - e.g. some Lagoons, a saildrive is placed behind the rudder! In this case it works better aft than ahead, but it can be used effectively on any cat
I have read all the comments and this question was never asked. Going forward makes all the sense. I have an issue with going in reverse when you say "do the reverse". The wind is the same so wouldn't the "do the reverse" mean to keep on using the downwind engine in reverse with helm to port to counter the engine? Don't you need the downwind engine in reverse to turn the cat into the wind in order to cancel it? Your suggestion uses the upwind engine in reverse which in my mind adds up to the wind force due to the turning effect. The way I see it the only force battling the wind in your suggested approach going reverse is the helm action. The only reason I can think of in favor of using the upwind engine in reverse is perhaps somehow related to the inverse prop and rudder position (with respect to going forward). But still, using only upwind engine in reverse would have a net effect of moving the cat even more downwind, wouldn't it? Can you please comment? Would my suggestion work at all and if not, why not? Perhaps the difference is subtle in favor of your approach and perhaps mine would fail altogether. I have not tried it. This is just a physics mind experiment. Perhaps this argument deserves a video? :)
I have reviewed this video completely and I can’t see where the confusion has arisen. In case something I said caused confusion, refer to the summary instruction at the end of the video. The latter part of the video answers your comment about the engine turning the boat - it is the turning moment that is useful, because countering it with rudder creates the later force you need to hold against the wind.
Great videos you are doing 🙂. I have seen your Lagoon version of waking the cat sideways, and that makes a lot of sense (needing to steer opposite because the props are aft the rudders). But in this case (leaving from a mediterranean mooring) I guess steering opposite would not solve the problem. I cannot find if you have made a video explaining this situation in Lagoons? I would imagine giving a little forward trust on the windward engine (less than on the leeward engine) would give you that extra sideways trust you would be missing from the leeward because the rudder is placed in front of the waterjet from the prop. Or?
Hi Mads. Many thanks for your appreciation. I think you are right… the prop and rudder relationship is not so important once you have forward way on, so the same technique will work, but it may be that you end up with a little more power and rudder than on other cats. I spent some time on a Lagoon 380 in Croatia a few years ago and I don’t remember having to do anything different from on Leopards, which is our usual charter pick… Going astern to get in we never had a need for high power, but it all worked as expected…
@@theboatcheat1204Yes i saw the video and it is very helpful. But it explain how to leave the dock (sideways and forward). How do I use this technique in order to moor (reverse) when the wind comes from starboard?
@@davidelalouf1774 Ah of course… the same technique works in a Lagoon. However, whereas the effect is stronger going forward in a conventional arrangement, it is stronger in reverse in a Lagoon. I chartered a Lagoon in the Med a few years ago and handling for stern-to mooring was really good - I reckon arriving is harder than leaving, so the Lagoon arrangement was a bonus.
@@theboatcheat1204 Thanks for the reply, but in the sequence you dropped the port line while the port engine was in forward and then put that engine into neutral before dropping the starboard stern line. What am I missing?
@@johnditoro1676 Nothing - this is a hitherto unnoticed editing error! I always put the upwind engine in idle ahead while the leeward stern line is removed, so that the boat doesn’t drift too much to leeward thanks to tension in the upwind line. Then the leeward engine is put back in gear to cause the swing to the windward side of the space so that it is somewhere near the middle once the upwind stern line is recovered. I am clearly less careful when editing complicated graphic sequences! Thanks for pointing it out - it need re-doing soon anyway because it is very clunky…
New subscriber here - really excellent videos! In your experience is there an upper limit to the wind speed that would make this technique inadvisable? I have a Leopard 48 sailing cat with loads of windage and I'm always worried about losing the bow when going astern. I would be nervous trying this in really high wind!
It all depends on the boat, the location and also the load on the boat, so it would be inappropriate to put a number on it…. but the reality is that if you arrive back at the charter base and conditions are difficult, it will always help you to do this… and in bad weather they will be assisting usually…
You forgot to mention that if the rudders are located forward of the engines, as in Lagoon catamarans, then the rudders should be turned in the opposite direction shown.
A good question - the video currently in production is an overview of stern-to mooring with lazy lines, and the next is stern-to mooring with an anchor. They will be up very soon!
No, it works for all twins with props in front of twin rudders… there are other videos on the channel covering props behind rudders (e.g. Lagoon) and twin stern drives or outboards… each has a slightly different technique. Thanks for showing your appreciation!
You are of course correct about the wind taking the bow first, but the clip is not wrong - it is about Mediterranean mooring, where there is almost no tidal stream, which is why stern-to mooring is used so widely. I have used this techniques to squeeze in and out of several spots which are exposed to substantial crosswind and because the charter bases have limited space there is not much room between boat - at the beginning of a trip, when you aren’t necessarily familiar with the handling of the boat, this technique is a great way to simplify getting out cleanly. At the end of the trip, when you inevitably arrive back mid-to-late afternoon in the hight of the breeze with a big audience it avoids you taking part in the “whacky races”. I have used it in a Leopard 44, which has enormous windage, in a substantial cross-breeze, and it was easily manageable.
This is the best boat handling tutorial I've ever seen on YOU-TUBE.
Thank you! Hope you find it helpful on the water...
This is very helpful, thank you for creating. I am creating a library and print of screen shots for reference.
100% agree!
Outstanding information and ilustration, thank you
Excellent video. Thank you so much for sharing the information with the rest of the world!
Great Video.... Every little cheat I can pick up will help me get out of a jam.
Your techniques are amazing you are a top lecture i admire so far
excellent video! this is going to make docking so much better for me as its always windy. thanks
Thank You guys awesome Video It really helps cant wait to try it
These are super helpful and easily understood. Thank you.
Glad it was helpful!
This is great thanks so much
looks like a real cheat! Will try next time. I hate marinas but these is the start and end of the charter, unfortunately.
Thank you so much! Very interesting!
You're very welcome!
Helpful video. On most cruising cats the rudder action will be much greater in forward than in reverse.
On the most Lagoon (Maybe all of them) the prop is behind the rudder !
Of course it is 😁@@wolfgangdostmann2308
Good stuff....ty
Excelent!
brilliant!
Best boat handling information of all time!!
Thank you for this kind comment - I hope you find the information useful!
Great video.
Thanks!
Awesome tutorial. much better than learning via trial and error! Thanks for taking the time to explain this as we boat in super high winds here in the San Francisco Bay where the winds routinely blows 20-35 knots every afternoon during spring and summer months and there is always a stiff cross wind when docking
Thanks - glad you found it helpful. Wind always seems to be from the wrong direction when docking, doesn't it?
The idea of using the downwind engine while turning the rudder towards that side is sound. A suggested improvement in your presentation is as follows: the force vectors cannot arbitrarily be relocated to the center of mass of the boat. Those force vectors act at the location of the forces. Thus, the sideways rudder force pushes the boat in the upwind direction as shown, but since the force is applied at the location of the rudders it also provides a turning moment that rotates the bows downwind. Similarly for the wind force that acts predominantly on the bows - it provides a side force as well as a turning moment that rotates the bows downwind. The offset engine thrust is the only force that opposes both of these rotations. The rudders provide the only adjustable control of lateral force, and the engine provides the only adjustable control of rotation. So the right way to think about the helmsman's job is to use the rudders to adjust lateral position, and the throttle to adjust rotation. It's important to remember that the rudder forces will be affected by the engine thrust if they are in the wake of the props (this will be a factor either in forward or reverse depending on rudder location). Also, the rudder force depends on the square of the boat speed, with zero force at zero speed (neglecting prop wash if applicable) so it's essential to get the boat moving for the rudders to work at all. I hope that all makes sense...
Thank you for your comments. The forces are not arbitrarily moved to the CG, the effect of a force at any point not at the CG - of more accurately the biased mean between CG, Aerodynamic Centre (windage) and Hydrodynamic Centre (current effects), which varies from boat to boat - will always create a force and a turning moment. The sum of these moments and vectors acts on the CG with the caveat already mentioned… so they are moved there to represent in a simpler way what happens to the vessel… nothing arbitrary about it, just mathematics.
Makes total sense. After you watch it. LOL
Excellent video, thank you very much.
There are catamarans that have the propellers behind the rudders. So the propellers don't stream the rudders (in forward motion). That means there is only rudder action when the boat is moving. I guess this technique doesn't work then, does it?
It does work, but in a different way - see the video for Lagoons on this channel for the technique with such boats…Thanks for your appreciation!
I love this technique and memorized it but only now realize things are different on a lagoon. Can you explain what is different ? Greatly appreciated!!
For this manoeuvre the Lagoon behaves the same - it is the displacement of thrust and drag that causes the lateral drift… however, for moving sideways off the dock you need to use a different technique than with other cats - this is discussed here czcams.com/video/5OMAuIHdHKc/video.html
Awesome video. I am new to cats this year. We will be sailing an FP 36 Mahe next season. The props are aft of the rudders. I would use the “lagoon video” technique when leaving the dock however, I am guessing the docking procedure stern to wouldn’t change? Am I understanding that correctly?
Absolutely spot on. Enjoy the Mahe!
Can’t wait to try it. Thank you so much
I really appreciate this, and your going forwards guide is great. But why does the rudder have the same impact going backwards as forwards? Going forwards you get the prop thrust over the rudder, whereas going backwards you only have the slow speed of the boat through the water which is substantially less.
You are, of course, absolutely correct. More speed is needed going aft to have the same effect, but it works predictably and consistently. On some catamarans - e.g. some Lagoons, a saildrive is placed behind the rudder! In this case it works better aft than ahead, but it can be used effectively on any cat
I have read all the comments and this question was never asked. Going forward makes all the sense. I have an issue with going in reverse when you say "do the reverse". The wind is the same so wouldn't the "do the reverse" mean to keep on using the downwind engine in reverse with helm to port to counter the engine? Don't you need the downwind engine in reverse to turn the cat into the wind in order to cancel it? Your suggestion uses the upwind engine in reverse which in my mind adds up to the wind force due to the turning effect. The way I see it the only force battling the wind in your suggested approach going reverse is the helm action. The only reason I can think of in favor of using the upwind engine in reverse is perhaps somehow related to the inverse prop and rudder position (with respect to going forward). But still, using only upwind engine in reverse would have a net effect of moving the cat even more downwind, wouldn't it? Can you please comment? Would my suggestion work at all and if not, why not? Perhaps the difference is subtle in favor of your approach and perhaps mine would fail altogether. I have not tried it. This is just a physics mind experiment. Perhaps this argument deserves a video? :)
I have reviewed this video completely and I can’t see where the confusion has arisen. In case something I said caused confusion, refer to the summary instruction at the end of the video. The latter part of the video answers your comment about the engine turning the boat - it is the turning moment that is useful, because countering it with rudder creates the later force you need to hold against the wind.
Great videos you are doing 🙂. I have seen your Lagoon version of waking the cat sideways, and that makes a lot of sense (needing to steer opposite because the props are aft the rudders). But in this case (leaving from a mediterranean mooring) I guess steering opposite would not solve the problem. I cannot find if you have made a video explaining this situation in Lagoons? I would imagine giving a little forward trust on the windward engine (less than on the leeward engine) would give you that extra sideways trust you would be missing from the leeward because the rudder is placed in front of the waterjet from the prop. Or?
Hi Mads. Many thanks for your appreciation. I think you are right… the prop and rudder relationship is not so important once you have forward way on, so the same technique will work, but it may be that you end up with a little more power and rudder than on other cats. I spent some time on a Lagoon 380 in Croatia a few years ago and I don’t remember having to do anything different from on Leopards, which is our usual charter pick… Going astern to get in we never had a need for high power, but it all worked as expected…
Going for two weeks Lagoon 40 and 450 in October - will make some testing 😅
Hey, any chance of doing some of these that demonstrate how to crab a twin outdrive over or how to move a boat sideways?
This one might do the job…. czcams.com/video/-d4RWfuv0bI/video.html
Great video. can you explain how to do that on a lagoon catamaran (rudders before the propellor)
Thank you! There is a separate video on the channel specifically for the Lagoon and other cats with the props after of the rudders.
@@theboatcheat1204Yes i saw the video and it is very helpful. But it explain how to leave the dock (sideways and forward). How do I use this technique in order to moor (reverse) when the wind comes from starboard?
@@davidelalouf1774 Ah of course… the same technique works in a Lagoon. However, whereas the effect is stronger going forward in a conventional arrangement, it is stronger in reverse in a Lagoon. I chartered a Lagoon in the Med a few years ago and handling for stern-to mooring was really good - I reckon arriving is harder than leaving, so the Lagoon arrangement was a bonus.
Not sure if you are still responding to questions. Why do you put the engine into neutral prior to releasing the starboard stern line?
A good question - if the crew drop the line it may foul the prop.
@@theboatcheat1204 Thanks for the reply, but in the sequence you dropped the port line while the port engine was in forward and then put that engine into neutral before dropping the starboard stern line. What am I missing?
@@johnditoro1676 Nothing - this is a hitherto unnoticed editing error! I always put the upwind engine in idle ahead while the leeward stern line is removed, so that the boat doesn’t drift too much to leeward thanks to tension in the upwind line. Then the leeward engine is put back in gear to cause the swing to the windward side of the space so that it is somewhere near the middle once the upwind stern line is recovered. I am clearly less careful when editing complicated graphic sequences! Thanks for pointing it out - it need re-doing soon anyway because it is very clunky…
@@theboatcheat1204 Thanks again. I'll be sailing a cat in Croatia in a little less than 2 weeks. Looking forward to trying some of your "cheats".
New subscriber here - really excellent videos! In your experience is there an upper limit to the wind speed that would make this technique inadvisable?
I have a Leopard 48 sailing cat with loads of windage and I'm always worried about losing the bow when going astern. I would be nervous trying this in really high wind!
It all depends on the boat, the location and also the load on the boat, so it would be inappropriate to put a number on it…. but the reality is that if you arrive back at the charter base and conditions are difficult, it will always help you to do this… and in bad weather they will be assisting usually…
You forgot to mention that if the rudders are located forward of the engines, as in Lagoon catamarans, then the rudders should be turned in the opposite direction shown.
Indeed - there is a separate video covering Lagoons in the same playlist.
After docking between both boats whats next.?
A good question - the video currently in production is an overview of stern-to mooring with lazy lines, and the next is stern-to mooring with an anchor. They will be up very soon!
Amazing video!!!! does this work only for cats?
No, it works for all twins with props in front of twin rudders… there are other videos on the channel covering props behind rudders (e.g. Lagoon) and twin stern drives or outboards… each has a slightly different technique. Thanks for showing your appreciation!
This is wrong. You should be turning into the wind or current whichever is stronger. Wind will always take the bow before it takes the stern
You are of course correct about the wind taking the bow first, but the clip is not wrong - it is about Mediterranean mooring, where there is almost no tidal stream, which is why stern-to mooring is used so widely. I have used this techniques to squeeze in and out of several spots which are exposed to substantial crosswind and because the charter bases have limited space there is not much room between boat - at the beginning of a trip, when you aren’t necessarily familiar with the handling of the boat, this technique is a great way to simplify getting out cleanly. At the end of the trip, when you inevitably arrive back mid-to-late afternoon in the hight of the breeze with a big audience it avoids you taking part in the “whacky races”. I have used it in a Leopard 44, which has enormous windage, in a substantial cross-breeze, and it was easily manageable.