[Vehicles, LT] Points-of-Sailing Effects

[Kax]

Originally Posted by Gigermann

Although I think I've found a sufficient answer to the original question, I have another related one: what would a sailing ship's performance accurately be, compared to its forward performance, while "backing"—wind fully against the sails, pushing them back against the masts—effectively driving in reverse? It doesn't appear to be very efficient (from what I've observed), but it does have some momentum to it. I haven't seen (or I've missed it) where this has been discussed in any of the GURPS material. (And Vehicles specifically excludes sailing vessels from moving in reverse, though that's clearly not true IRL if the wind is right.)

For anything bigger than a single mast it's faster and safer and easier to turn the ship around rather than try and go backwards.

[Gigermann]

Originally Posted by Kax

Full-rigged ship: all masts have square sails, but you can have fore-and-aft stay-sails as well between the masts.

https://en.wikipedia.org/wiki/Full-rigged_ship

Challenge to include: junk-rigged, including junk-rigged with a spinnaker.

"Square", "Fore-and-Aft", and "Full" rigging types, as I'm referring to them here, are terms-of-art in GURPS Vehicles on p.30, and in VE1. I realize the rules' definitions aren't exactly broadly correct.

As to the other types, many types other than the three in Vehicles (including junk and spinnakers) are discussed in VE1, though for performance purposes, they refer back to the original three.

Originally Posted by Kax

For anything bigger than a single mast it's faster and safer and easier to turn the ship around rather than try and go backwards.

Backing is a common enough operation for age-of-sail ships, especially in port or navigating rivers/channels. I can't relocate the original source I stumbled across, but it had a diagram of a series of maneuvers to get a ship out of a twisting river that had it turned every-which-way you can think of to get out.

[Edit] Found the image I was referring to above

[Rupert]

Originally Posted by Gigermann

Backing is a common enough operation for age-of-sail ships, especially in port or navigating rivers/channels. I can't relocate the original source I stumbled across, but it had a diagram of a series of maneuvers to get a ship out of a twisting river that had it turned every-which-way you can think of to get out.

I think the answer is "very slowly". Aside from being inefficient, the masts and rigging are not set up for it, and the strain can easily break masts if there's much sail up, especially on a multi-masted largely square-sailed ship. Given that you'd be doing it as part of some odd and probably tricky manoeuvre anyway, rather than when trying to make distance, I'd just assign and length of time to perform that manoeuvre, and start with the skill checks.

[Kax]

Originally Posted by Gigermann

"Square", "Fore-and-Aft", and "Full" rigging types, as I'm referring to them here, are terms-of-art in GURPS Vehicles on p.30, and in VE1. I realize the rules' definitions aren't exactly broadly correct.

Which is why I have to convert things a bit all the time while using those rules.

Originally Posted by Gigermann

Backing is a common enough operation for age-of-sail ships, especially in port or navigating rivers/channels. I can't relocate the original source I stumbled across, but it had a diagram of a series of maneuvers to get a ship out of a twisting river that had it turned every-which-way you can think of to get out.

[Edit] Found the image I was referring to above

Common enough=/=easy or safe. If you can turn, you turn in preference to backing even if turning is hard.

This is why tugs exist; oared tugs existed in mediaeval times for this very reason, especially since anything that's likely to need any help turning is going to manoeuvre like an overweight cow. They'd also use their own boats for the same purpose.

So the only time you'd do it is, like the twisting river, there's no space to turn around.