Towing sailing yacht to sailing yacht.

[Sailing65]

1. The bridle to equally distribute load? Example stern bridle tied off at midship clear, aft one turn on one poss two whinges one turn around stern cleat?

Q. Does this effectively distribute loads across those fittings?
Q. How do you ensure correct equalisation of load across those fittings both port/stern?
Q. Attaching tow top to the bridle, bowline ok or shackle, best knot to ensure correct equalisation?

Thanks in advance

 

[Refueler]

I have towed many a yacht over the years .....

View from towed boat :

From stern of my boat :

Most time if weather is good and nothing untoward expected ... a simple bridle on the towing boat and a stout tow rope to the towed boat.

The bridle should be halved and I prefer a fig 8 made at that halfway - creating a loop to shackle or make fast to. The bridle ends made fast to decent cleats on towing boat or to winches. if sufficient length - then doubling to second cleats as in midships is a good idea.

The tow line should be made to the foredeck samson post or main cleat used for anchoring / mooring ... with tail end if possible run back to another cleat or winch as back up.

The tow above was for about 3hrs .. basically we needed to get to destination quickly and if we'd gone separately - the other boat would have lagged behind and too late. The tow averaged 6 - 7kts ....

My boats - I always carry a stout long line suitable for towing .. Bridles can be made up from mooring lines.

If you expect rough weather or open waters - then a length of chain from bridle to tow line provides a shock absorbing buffer ...

 

[RunAgroundHard]

1. The bridle to equally distribute load? Example stern bridle tied off at midship clear, aft one turn on one poss two whinges one turn around stern cleat?

Q. Does this effectively distribute loads across those fittings?
Q. How do you ensure correct equalisation of load across those fittings both port/stern?
Q. Attaching tow top to the bridle, bowline ok or shackle, best knot to ensure correct equalisation?

Thanks in advance

I don’t think you can guarantee even force distribution between the midship and stern cleat. The bridle will not even distribute the loads evenly between cleats each side, as the boat being towed slews. All you can do is set up as best you can. If you need to distribute loads because the single cleats are not strong, then consider if towing is acceptable. You may end up with significant force on one cleat. A single turn, or even two turns will slip under force, putting more force on the midship cleat.

Having said that, I would do what you are proposing except use my genoa sheet winches as they are mounted very strong, and only take a turn around my aft cleats. I don’t have fair leads on the stern. On the bridle I would tie a figure of eight on the bight which produces an eye, then tie the towing line onto the eye with a round turn and two half hitches, with the dead end taped up. Don’t let the tow line slide along the bridle, it may wear out fast.

Being towed, similar except from the bow, deck stepped mast, so I would not use that as a strong point, might if it was keel stepped. For short tows in fair weather, I would take the line through my anchor fairlead, and onto the capstan on my anchor windlass. It is secured strongly but I would not use if surging was expected.

 

[Refueler]

1. The bridle to equally distribute load? Example stern bridle tied off at midship clear, aft one turn on one poss two whinges one turn around stern cleat?

No.

Q. Does this effectively distribute loads across those fittings?

No

Q. How do you ensure correct equalisation of load across those fittings both port/stern?
Q. Attaching tow top to the bridle, bowline ok or shackle, best knot to ensure correct equalisation?

Thanks in advance

see my reply earlier.

 

[William_H]

You can fit a sheave to the bridle so tow rope pulls on the sheave. However I don't think this necessary. Loads on towing a boat should not be large provided you do not jerk the tow line with rapid acceleration. Tow rope on one side can work ok but will provide a steering tendency to the towing boat. So yes a bridle or centre attachment is better.
One significant factor is the steering effect that the load can have on the towing boat. If the towed boat veers to one side the load will pull the stern in a way difficult to counteract with rudder. (bridle or not) Emphasise that towed boat must be steered to centre of towing boat at all times. Interesting that tug boats have a tow point as close as possible to centre of tug (fore and aft and midships) to reduce this steering effect. Likewise ski tow boats will have a pull from near centre of boat enabling the towing boat ton turn unhindered. ol'will

 

[Refueler]

You can fit a sheave to the bridle so tow rope pulls on the sheave. However I don't think this necessary. Loads on towing a boat should not be large provided you do not jerk the tow line with rapid acceleration. Tow rope on one side can work ok but will provide a steering tendency to the towing boat. So yes a bridle or centre attachment is better.
One significant factor is the steering effect that the load can have on the towing boat. If the towed boat veers to one side the load will pull the stern in a way difficult to counteract with rudder. (bridle or not) Emphasise that towed boat must be steered to centre of towing boat at all times. Interesting that tug boats have a tow point as close as possible to centre of tug (fore and aft and midships) to reduce this steering effect. Likewise ski tow boats will have a pull from near centre of boat enabling the towing boat ton turn unhindered. ol'will

The tow attachment point for Tugs and Ski Boats - is purely to facilitate manoeuvrability ...

Having a tow line able to move on the bridle is NOT a good idea ... it is best FIXED to the centre point of the bridle.