Help with this situation, "Max Drag Weight"?

[shawjames]

Ok, my group just lost their cleric down an underground river. The rest of the group is thinking of letting someone swim downstream (the river goes down into the rock, so whoever goes would have to hold their breath). They are thinking of sending the best swimmer, and breath holder, a dwarven barbarian. The problem I am faced with is, how hard would it be to pull him back UP-stream? The underground river is flowing at 60 feet per round, or about 7 miles per hour.

I am thinking of just making the pull weight out to be the swimmer's weight times 7 (mi/hr). Or 195lb dwarf times 7 mi/hr = 1365 drag weight.

The rest of the party (Paladin 16str, Rogue 15str, Wizard 12str) have a combined Max Drag Weight of 2800lb. So with my math, they could easily do it.

Anyone have a more realistic calculation?
Thanks!!

 

[Artoomis]

Your method is okay.

7 miles per hour? Wow - that's a really swift current. The most dangerous aspect of this whole little venture may be the tensile strength of the rope! Can the rope really hold 1365 lbs? That's the key question here!

If it's silk rope, it can be burst with a Strength check vs. DC 24. Perhaps it would be good to force a strength check (only one) against the rope to see if it bursts (I know that's not what they are trying to do, but it would work as a kind of saving throw for the rope).

The way I would do this, to be fair, is to use the strength table to see what the equivalent strength to hold 1365 pounds would be - answer:

1365/5 = 273, or a 20 str (checking against the max load). This would mean +5 on the d20 rolls vs. DC 24 - on a 19 or 20, the rope bursts. If this rope is well-used, and never replaced, a circumstance penalty of +2 on the roll would be fair. That seems reasonable - some risk, but not too much, and it can be avoided by taking the simple, normal precaution of using TWO ropes - one just in case the first breaks.

Of course, they can only drag him back 5' per round, because that's all you can moce when dragging a super-heavy load.

This may not be exactly realistic, but it certainly captures the whole flavor of how this would work.

All-in-all, this should be possible, but with significant risk due to the very swift current.

 

[Vaxalon]

I'd like to point out that a seven mile per hour current is faster than 90% of the whitewater rapids on Earth... most whitewater rapids are between 5 and 6 miles per hour.

Personally, I don't have a problem with this. A fantasy world SHOULD be bigger, stronger, bolder, and more dangerous than the real world. Not only that, real world physics shouldn't really enter into it.

If you ARE interested in real world physics, though, you should know that a cataract with water that's moving that fast needs to be a very recent event, geologically speaking... like within the last thousand years or so. After a few thousand years, the bed gets eroded down and the areas upstream and downstream from it would get faster, but that spot would get slower as it creates wider banks and shallower streambed.