Shipwreck survival

[NineDaysDead]

Originally Posted by Refplace

Where do you come up with either 30 MPH winds and that extreme cold?

I'm going with a worst case example. That's what it takes to actually threaten these guys. Anything less than that and they're laughing!

[Vynticator]

Originally Posted by NineDaysDead

I'm going with a worst case example. That's what it takes to actually threaten these guys. Anything less than that and they're laughing!

Hmm. Southern Sweden pretty much never gets *that* cold! more likely the nights will be about 20'F if it's windy and at the cold end of average.

Couple of points- using The Last Gasp means their HT and Swimming skills and Survival skills will be at penalties by the time they leave the water. There's also the 'deep fatigue' rules to consider. I'm also thinking the regeneration may be interrupted once fatigue falls below a certain level.

-swimming: we haven't discussed penalties for open water swimming, or for swimming in rough seas. I'd say lake swimming is -1, sea swimming -2 to skill, worse if it's rough. You've got sighting, waves and tides to contend with.

Back on shore: The range of temperature tolerance GURPS gives starts at 35F for normal humans and goes up to 90'F. I think one has to assume clothing is factored into those numbers. If you're nearly naked I'm pretty sure 35F would be outside your comfort zone. So I think the temperatures and physical challenges we're talking about will test even these fellas.

[Agemegos]

Originally Posted by Vynticator

I understand on a clear day you can see the coast 7 miles away from sea level, I am told by the inter web. So if they head broadly the right way and the storm clears after half an hour or so, they may see shore soon after that.

That sounds more like standing at sea level (i.e. with any eye height of five and a half feet) than immersed at sea level (i.e. with an eye level only a few inches above the waves).

[Anthony]

Originally Posted by Agemegos

That sounds more like standing at sea level (i.e. with any eye height of five and a half feet) than immersed at sea level (i.e. with an eye level only a few inches above the waves).

Horizon distance is typically given as 3.57 km * sqrt( height / 1m ), so 7 miles is too far even for someone standing up, and for someone swimming would be more like 1-1.5 km. However, you can see things that are over the horizon if they're tall enough -- if we assume 1.3 km horizon from swimming, and 10 km for the target (total 11.3 km, or 7 miles) the object needs to be about 8 meters tall to be visible, which is a decent-sized tree but not impossible, and mountains would be visible quite a bit farther, probably out to the range at which atmospheric haze wipes them out.

[Vynticator]

Originally Posted by Anthony

Horizon distance is typically given as 3.57 km * sqrt( height / 1m ), so 7 miles is too far even for someone standing up, and for someone swimming would be more like 1-1.5 km. However, you can see things that are over the horizon if they're tall enough -- if we assume 1.3 km horizon from swimming, and 10 km for the target (total 11.3 km, or 7 miles) the object needs to be about 8 meters tall to be visible, which is a decent-sized tree but not impossible, and mountains would be visible quite a bit farther, probably out to the range at which atmospheric haze wipes them out.

Thanks for this helpful formula. There's a rocky headland at the northern edge of the bay which is 41m above sea level.

[Anthony]

Originally Posted by Vynticator

Thanks for this helpful formula. There's a rocky headland at the northern edge of the bay which is 41m above sea level.

Sea-level air often has pretty poor transparency, so you can certainly justify quite a lot shorter vision range, but that gives a maximum range.

[Tuk the Weekah]

Originally Posted by Vynticator

Thanks for this helpful formula. There's a rocky headland at the northern edge of the bay which is 41m above sea level.

With a headlands that high, the swimmers may see the sea birds playing in the wind currents created by the headland before they sight land itself.

[Flyndaran]

Originally Posted by Vynticator

...
-swimming: we haven't discussed penalties for open water swimming, or for swimming in rough seas. I'd say lake swimming is -1, sea swimming -2 to skill, worse if it's rough. You've got sighting, waves and tides to contend with.
....

Gurps skills assume use in the field. Swimming isn't how to not drown by staying afloat. That's default use with +4 for perfect conditions.
But extra rough seas certainly would accrue penalties.

[mikec964]

This will be a huge help for my campaign, too.

Swimming rules say you roll every 6 long-distance turns (basically per minute) to see if you lose an FP, and every every 5 minutes for swimming to see if you start to drown. I think.

If the players are going to swim 5 miles (8800 yards), and the typical speed is 60 yards/minute, that's 146 die rolls. I think they'd rather drown than roll that many times.

How do you turn something like that into something like 5 to 20 rolls? It'd be nice to have, maybe, 5 rolls before their FP drops to 1/3, and 5 rolls after that to reach shore.

How would you handle it?