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Old 04-19-2021, 01:01 PM   #1
Stormcrow
 
Join Date: Aug 2004
Location: Ronkonkoma, NY
Default Vehicles, range, fatigue

Unpowered vehicles rowed or pulled by beings have Range F, which means the FP of the rowers or pullers and their provisions limit range.

Is there anywhere in the rules that FP costs for rowing or pulling? How many men do I really need to keep my 30-oar longship moving up the river without halting? How far will my wagon drawn by two horses really go before resting?

"Rowing is kind of like hiking" is an unsatisfying answer.
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Old 04-19-2021, 01:32 PM   #2
Rupert
 
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Location: Wellington, NZ
Default Re: Vehicles, range, fatigue

Quote:
Originally Posted by Stormcrow View Post
Unpowered vehicles rowed or pulled by beings have Range F, which means the FP of the rowers or pullers and their provisions limit range.

Is there anywhere in the rules that FP costs for rowing or pulling? How many men do I really need to keep my 30-oar longship moving up the river without halting? How far will my wagon drawn by two horses really go before resting?

"Rowing is kind of like hiking" is an unsatisfying answer.
Rowing at a slow speed you'd use for long distance travel is like hiking. Rowing flat-out, as you would in a triērēs vs triērēs battle is like running or sprinting.

Now, what's lacking are detailed rules for speed vs FP consumption. The best we get is that ~75% of top speed is like hiking, and thus can be continued until the sleep rules take the rowers out of action, and that top speed uses FP like running does and thus costs 1FP per failed HT roll (presumably you could substitute Boating (Unpowered) for HT), rolling once per minute.

This is actually pretty good for professional oarsmen - they'll have HT/Boating at 12 or so, and even with the normal 10FP can spend 7FP before speed drops to 1/2, and thus will be rowing at top speed for nearly 30 minutes, on average. I'd consider ruling that FP is spent as sprinting (i.e. four times as fast), or make some more detailed rules that allow for 'hiking', 'running', and 'sprinting' speeds.
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Old 04-19-2021, 01:44 PM   #3
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Default Re: Vehicles, range, fatigue

I'll add that what Rupert is saying is on Campaigns p463
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Old 04-19-2021, 02:53 PM   #4
Stormcrow
 
Join Date: Aug 2004
Location: Ronkonkoma, NY
Default Re: Vehicles, range, fatigue

Ah, okay, the rule I was looking for is in the section on Cruising Speed. Thanks.
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Old Today, 05:12 AM   #5
Taneli
 
Join Date: Aug 2004
Location: Helsinki, Finland
Default Re: Vehicles, range, fatigue

Speaking of rowed watercraft with multiple rowers, when you have less than a full compliment, how much would you reduce the speeds that the vessel can achieve?

I mean, you could just call it that with 50% of rowers you can achieve no more than 50% of the top speed, but does anyone have a better idea? It's been too long since I last rowed a boat with multiple rowing positions to remember how it was affected.
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Old Today, 06:35 AM   #6
johndallman
 
Join Date: Oct 2010
Location: Cambridge, UK
Default Re: Vehicles, range, fatigue

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Originally Posted by Taneli View Post
Speaking of rowed watercraft with multiple rowers, when you have less than a full compliment, how much would you reduce the speeds that the vessel can achieve?
At constant speed, thrust from rowers is equal to drag. And drag is proportional to velocity squared. So if you halve the number of rowers, you divide speed by sqrt(2).
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Old Today, 09:02 AM   #7
Varyon
 
Join Date: Jun 2013
Default Re: Vehicles, range, fatigue

Quote:
Originally Posted by Rupert View Post
... or make some more detailed rules that allow for 'hiking', 'running', and 'sprinting' speeds.
Quote:
Originally Posted by johndallman View Post
At constant speed, thrust from rowers is equal to drag. And drag is proportional to velocity squared. So if you halve the number of rowers, you divide speed by sqrt(2).
I previously worked out an alternative system for towing, poling, and rowing vessels, here. The tl;dr of the final system is:

Step 1) Divide the weight of the vessel by its length in yards. That value works as-is for rafts and square barges; for a vessel with rounded lines, multiply by 0.7; for a vessel with long lines, multiply by 0.5. This is "effective weight" (eW).

Step 2) (poling/rowing only) Combine the BL's of all polers/rowers. For poling (and paddling, basically any "arm only" option), use 30xBL for sustained poling (functioning similarly to Hiking), 70xBL for more rapid poling (comparable to Jogging), and 150xBL for full-speed (comparable to Sprinting). For rowing, these values are instead 50xBL, 100xBL, and 200xBL, respectively. The end result is "power" (P).

Step 3) For towing, use eW multiplied by Move squared as encumbrance (spread out over all characters/creatures involved). For poling/rowing, divide P by eW, then take the cube root of the result to determine maximum Move. That is:
Towing: eW * Move^2 = encumbrance
Poling/Rowing: (P/eW)^(1/3) = Move

In all cases, Move is relative to the flow rate of the body of water. If you need to tow a vessel on a river, subtract the flow rate from Move before squaring it if traveling downstream, add the flow rate to Move before squaring it if traveling upstream. If you need to pole/row a vessel on a river, add the flow rate to the determined maximum Move if traveling downstream, subtract it if traveling upstream.

As an example, let's take a 10-yard raft, and load it up to 1000 lb (including its own weight; note I'm just pulling numbers out of the air, here). It has an eW of 100 lb (1000/10). Towing it at relative Move 1 reduces the half-ton load to 100 lb - with 5 people of average ST, they'd each be right at Light Encumbrance (20 lb), and could comfortably move at Hiking speed. Towing it at a relative Move 2 means that half-ton load is instead 400 lb (multiply by 2^2), meaning either Extra-Heavy Encumbrance (and the characters cannot get up to Move 2 anyway; they might be at this level if towing upstream, however) or needing more people (or stronger animals) doing the towing. (EDIT: Also, note that in this case, if you need to move much faster than 3 yards/second relative to flow rate, you're better off just carrying it - the break-even point is the square root of 10, or around 3.16) Five people poling or rowing it means a combined BL of 100. Poling at a "hiking" rate means a P of 3000 (30x100), a P/eW of 30, and thus a maximum Move of 3.1 (cube root of 30). Poling at a "jogging" rate means a P of 7000, a P/eW of 70, and maximum Move of 4.1. Poling at a "sprinting" rate gives a P of 15000, a P/eW of 150, and a maximum Move of 5.3. For rowing, the maximum Moves are 3.7, 4.6, and 5.8, respectively.
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Last edited by Varyon; Today at 09:10 AM.
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Old Today, 10:27 AM   #8
Anthony
 
Join Date: Feb 2005
Location: Berkeley, CA
Default Re: Vehicles, range, fatigue

Quote:
Originally Posted by johndallman View Post
At constant speed, thrust from rowers is equal to drag. And drag is proportional to velocity squared. So if you halve the number of rowers, you divide speed by sqrt(2).
The amount of thrust per rower is not constant as speed varies. If you assume constant power per rower rather than constant thrust, the result is dividing by the cube root rather than the square root.

In reality, neither constant thrust nor constant power is an accurate model, nor is drag coefficient constant, so while you can assume that fewer rowers is slower, how much slower is difficult to determine.
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