Quasqueton said:
I have only rudimentary knowledge of sailing, and no real-life experience on the subject. But what is right, here? How long, and well/safely, can an ocean-going ship sail without a crew managing the sails?
In our game situation, the ship was having to tack against the wind. This fact is what brought up the idea of just stopping the ship, to give the PCs enough time to decide how to handle the situation.
Quasqueton
Previous posts have replied with reference to various rpg rules systems for sailing ships. Which, if any, game mechanics you choose to apply to the situation is up to you, but here's my take on the reality of sailing square riggers.
You said the ship is a 140-foot-long, three-masted ship. Historically speaking, there are a variety of rigs that this could describe -- each with a different standard of manning and sailing. For the sake of the argument, we'll assume this means a mid to late 18th-century, full-rigged ship with square sails set on all three masts, fore-and-aft heads'ls and stays'ls, and a gaff-rigged spanker on the mizzen. In other words, your stereotypical pirate ship.
You said the ship was tacking upwind. Assuming the ship is rigged with courses, tops'ls, and t'gallants (no royals) and was sailing close-hauled (beating to windward) at the time the PCs took over, there are up to eight squares'ls set and eight stays'ls (not including the spanker) flying. This is a max of 16 sails under light wind conditions; heavier winds mean they'd be flying fewer sails. By the way, about 200 different ropes control those sixteen sails.
The weather conditions would make a HUGE difference in your inexperienced PCs' ability to run the ship. Under light conditions, they can make mistakes with little or no damage to the ship. It also takes fewer people to handle the lines in lighter conditions. In heavier weather, the consequences of their inexperience will matter more.
Even steering requires a lot of experience sailing close-hauled, or "tacking against the wind". If the helmsman turns too far upwind (a nominal degree when close hauled), he'll back the sails, which stops the ship, just as your players suggested. However, if the wind is blowing more than 15-20 knots, it is quite possible that backwinding the sails can damage or take down the rig. (Nearly all the support for masts on square rigs is designed for the force to be applied from aft -- pushing the boat forward. Backwind the sails and a LOT of force is suddenly inflicted on the forestays, which are meager compared to the shrouds and backstays).
More significantly, if the helmsman does back the sails and stops the boat with no damage, the crew must now adjust the sails to get the ship back underway; the helmsman can do nothing to help. So now your PCs must man the braces on the squaresails (the ropes that adjust the angle of the yards to the wind) and the sheets on all the stays'ls. Coordinating their action and understanding what must happen is beyond the capacity of most people without any square rigged sailing experience. So they're going to be stuck, and drifting downwind.
Now, you said the ship was beating to windward. This means tacking ship. How frequently this must be done depends on where they are: open ocean vs. coastal sailing. No matter, it is safe to assume that your neophyte PC crew will be unable to tack the ship at all. The first time they need to turn, they won't be able to. Period.
I don't say this lightly. I've sailed professionally on tall ships and traditional rigs for more than 10 years, mostly teaching neophyte trainees and students. If you set them loose to figure out how to tack a full-rigged ship on their own, they just can't do it. At best, it will take them more than a hour to struggle through the maneuver (and that's when a majority of them have some sailing experience). A full-rigged sailing ship is one of the most complex machines of the pre-Industrial Revolution. It takes a LOT to sail them.
So the short answer to your question is that your inexperienced PCs are not going to be able to go very far at all without having to adjust the sails, particularly if you have an equally inexperienced helmsman and the ship is trying to sail upwind. How many people they need to adjust the sails will depend largely on the wind strength. In lighter winds, a few people can move from sail to sail, adjusting one at a time. In stronger winds, the sails need to be trimmed together or the ship will suffer the effects.
By the way, you seemed most concerned about their need to go aloft. Climbing the rig is only required to unpack (unfurl) sails that were previously tied up (if you're going to set them), or to tie up (furl) sails that have been struck. Square sails work like old-fashioned theater curtains -- rising up and down with the help of ropes and pulleys. Those ropes are controlled from the deck, so you can stop the sail from catching the wind without leaving the deck, but a portion of it will still be flapping in the wind unless you climb up to tie it to the yard. In short, they can go a long way without having to go aloft.
In general, most RPG rules grossly underestimate the complexity of square-riggers and the experience of the sailors needed to operate them.
Carl