[HR] Naval Rules

Cool!

What about allowing Veterans to have reached level 1 (via the gain of 100XP, or the 1 month timeframe)? The pay for a “normal man” specialist sailor is 6GP/mo (matching your average crew) and the veteran status would add 12GP to that (D@W:C, pg 12, probably elsewhere as well) for a total of 18GP. (it also matches Light Infantry, which plain sailors are well matched to)

Veterans occur at a rate of 25% amongst human mercenaries, so that also subsumes any availability-per-market changes.

That does double the costs for veterans, however, it makes them a lot more effective in combat.

It does make them a lot more effective in combat, but that’s a very dangerous temptation. While oarsmen can fight (and indeed there’s evidence Athenian “skirmishers” were often armed rowers), you are risking the motive power of your vessel every time you use them in combat. Plus they’ll be even more tired than they would be from rowing if they’ve been fighting.

I’m just saying it’s something to be careful about, routinely using your oarsmen as infantry can significantly increase your crew turnover.

As with so many things about ancient times, pay depends on when precisely we’re looking at. Thucydides mentions that all of the sailors received 3 obols per day (8.45.2), while during the blockade/siege of Poteideia, pay was increased to 1 drachma per day for sailors and 2 per day for hoplites (who had an unpaid servant with them) (3.17.4). During the Quadruple Alliance of 420 BCE, the four allied states stipulated by treaty that the pay for a hoplite, sailor/oarsman, or toxotai was 3 obols per day, while a horseman would receive 6 obols. This suggests (to me, at least), that the 3/6 obol level was for domestic service, while the 1/2 drachma level was for expeditions away from the city (a sort of hazard pay, or, if you will, the difference between garrison forces and expeditionary forces). Individual captains might offer more to get better thranites, but Thuc. 6.31 states it was the captain’s decision: “The fleet had been elaborately equipped at great cost to the captains and the state; the treasury giving a drachma a day to each seaman…while the captains gave a bounty in addition to the pay from the treasury to the thranitae and crews generally…”

Roman sailors in the Imperial era were paid roughly the same as auxilia, or about 5/6 of a legionary’s pay. To the best of my knowledge, there’s no evidence of the pay varying, except for some of the immunes (like doctors or carpenters). That said, I haven’t looked that much at the Roman era yet, so it’s possible there are sources that I haven’t encountered yet.

One thing I am adding in now are some true Seaworthiness rules. I had originally left them out because my experience with them in 2e’s Of Ships and the Sea was that the numbers seemed rather arbitrary, and were not necessarily good indicators of the actual seaworthiness of the ship. I’m also working on abstracting ship construction so that it doesn’t require multiple spreadsheets to make a ship.

I just got a copy of Casson’s book from my local library. It’s thinner than I was expecting, but I’m looking forward to digging in.

If it’s slim, it’s probably “Ships and Seafaring in Ancient Times” from University of Texas Press, which is 160 pages. “Ships and Seamanship in the Ancient World” from Johns Hopkins University Press is 592 pages.

Ah, you are exactly right. I have the shorter work.

I love our forums so much.

So, I’ve been away on vacation, and coming back, I wanted to give a fairly long bit showing how I’m writing examples into the text now. This is intended to be part of the ship construction section. There are a couple references to tables not included in this excerpt, but the meaning should still be fairly clear. Some of the rules mentioned can be modified by special attributes.

Seaworthiness: Seaworthiness measures how well a ship performs under adverse conditions. Each point of seaworthiness allows a ship to ignore 1d6 of damage from weather each hour. Each point also provides a +1 bonus to any Seafaring checks made to repair the ship. The Base Seaworthiness of a ship is also its starting Armor Class.

Decks: The default for a ship is a single deck, plus a hold for cargo. This deck has a Useful Length equal to 70% of the ship’s total length and the same width as the ship. A second deck with the same area can be added by moving one row down on the Length to Draught column (i.e. from the 40 to 1 ratio to the 28 to 1 ratio), while a third deck makes the ship less stable, reducing seaworthiness by 1.

Rowers: The required number of rowers to achieve the Base Rowing Speed is equal to the ship’s length in feet divided by 5, multiplied by the ship’s beam divided by 4. If this number is odd, add one to make it even. Required rowers = (Length/5)*(Beam/4)

The maximum number of rowers on a single deck is equal to the ship’s Useful Length divided by 3, multiplied by the ship’s beam minus 8 feet and divided by 2. If this number is odd, add one to make it even. Maximum rowers = (Useful Length/3)*((Beam-8)/2)

Example: A ship is being built as a 7 to 1 rowed and sailed ship, 112 feet long and 16 feet wide. It has a Base Seaworthiness of 3. It requires (22.44) = 89.6 rowers to travel at base rowing speed. This is rounded up to 90. On a single deck, it can have (.737.3*4) = 104.5 rowers, rounded to 105 and increased to 106 to make it even. This ship can maintain its base rowing speed with only a single deck of rowers.

Rowers can be carried on multiple decks if desired in order to add more power without lengthening or widening the vessel.
Example: While this galley isn’t intended for combat, it may find itself being used as a swift transport, so the designer adds a second deck of rowing benches. The ship can now hold up to 212 rowers, and has a draught of 7 feet, instead of the 4 feet it would have originally drawn.

Oars weigh one stone per two rowers.
Example: Fully equipped with oars for 212 rowers and 20 spares, the oars would take up 116 stone of weight. In normal merchant service, however, the ship will only carry 50 rowers’ worth of oars, weighing only 25 stone.

Tonnage: The tonnage of a ship is a complicated thing. For purposes of simplification, these rules use Builder’s Old Measurement to calculate tonnage, which is the length of a ship, minus 60% of the beam, times the beam, times the draught, all divided by 94. Each ton of ship provides 1 structural hit point (shp). Each ton of ship also provides 200 stone of carrying capacity.
Example: The merchant galley is 112 feet long and 16 feet wide, with a 7 foot draught due to the second deck. This means its tonnage is (102.4167)/94 = 122 tons and it has 122 shp. The ship can be outfitted with up to 24,400 stone of crew, equipment, and cargo.

Looks good.

What’s the deal with warships? I’m thinking again of triremes and others, which would likely have a better AC than Seaworthiness.

On oarsmen, what about putting more than one rower to an oar? This has the advantage of more muscle power without additional beam/decks, but also requiring fewer trained oarsmen (since only the guy on the end needs to know what he’s doing). It’s probably how fours and above managed their numbers, adding oarsmen to each oar rather than more levels.

There will be options for heavy hulls, which will add armor for a small cost in speed. I’m probably also going to add a mortise-and-tenon hull type, which will add armor at the cost of being more expensive to build and repair. I’ve already added rules for clinker hulls (the default is framed carvel just because that’s what most people are familiar with), so adding a mortise-and-tenon carvel would make sense also.

Oarsmen are somewhat abstracted - oars weigh 1 stone per 2 rowers, but the rules don’t say whether that’s 2 oars each weighing half a stone, or a 1 stone oar with 2 rowers on it. If one really wants to get into the details, the formula for rowers [(Useful Length/3)*((Beam-8)/2)] is based on the math of how many rowers can be crammed into a space. The Useful Length/3 gives the number of files of rowers; each file needed around 3 feet of space to operate efficiently. The ((Beam-8)/2) is a rough estimate of how many rowers can fit next to each other in each file. A ship generally needed 2 feet of space from the hull to the first rower for leverage, plus a 4 foot walkway down the middle for people to move about on the deck, and each rower took up 2 feet of space. So, a 12 foot wide ship can have (12-8)/2 = 2 rowers per file; it’s only got 1 man per oar. A 16 foot wide ship can have 4 rowers per file, or 2 men per oar, and so on. Or, working the other way, each time you add an oarsman to an oar, it adds 4 feet of beam to the ship (one man per side times two feet per man).
This particular merchant ship, with 106 rowers, has 26 files of 4 and a file of 2 (probably at the bow, where it starts to narrow but can still fit shorter benches). The “50 oars” would likely be 24 two-man oars and a pair of one-man oars.
tl;dr answer: it’s abstracted into the rules.

The ability to add extra men per oar is also part of why ships are limited to three decks; it’s pretty much physically impossible to superimpose four decks’ worth of oars and actually get a useful working stroke out of them, and moving forward to the Age of Sail, ships generally carried cannon on three decks or less (and there are rules for forecastles and sterncastles for the partial fourth decks that were rarely used).

Excellent.

One other consideration: dry vs wet hulls. Will there be any speed bonus for having dried out your hull, or speed penalty for having been in the water for a while? Or both, with some sort of optimum period of time (a week?) with neither bonus nor penalty?

Most likely it will be gradual penalties for too much time in the water, to simulate both how ancient galleys became waterlogged over time and the fouling of ships in general. Ships can be dried out, careened, plated, or coated. Likely the first two will be actions that can be taken, while plating will be a ship option and coating (white stuff, black stuff, brown stuff) will be something that can be bought and applied to extend the time before the ship starts suffering penalties.

I was looking over the ship speeds in the corebook again, and there’s something that doesn’t jibe with what I’ve been reading.

The implication is that the more oarsmen that are powering a ship, the faster it is (under oars). So a pentekonter might be more nimble than a trireme, but it’s also slower. However, under sail the smaller vessel is faster.

At the risk of this phrase becoming cliche, ship speed is…complicated. It relies on many things. Among them are the amount of power (whether from oars, sails, a mechanical engine, etc), the ship’s length (which generally increases speed), and the ship’s block coefficient (essentially, how streamlined it is under water; the sleeker the ship, the faster it is).

Comparing the pentekonter to the trireme, a trireme was slightly longer (around 37 meters to 33 meters), about equally sleek, quite a bit heavier, and with a lot more power (170 rowers to 50 rowers). Both types of ships used a single sail, although I don’t know how different the sails were. So, the trireme should have a higher top speed under oars (although possibly slower to accelerate) under optimal conditions, but be the same speed or slower under sail and less nimble due to the heavier weight and need to coordinate multiple tiers of oars.

Note that the “less nimble” is still relative, though. A Greek trireme is still lightly built and quite nimble compared to a Hellenistic polyreme, when fours to sixes were the main battle fleet and larger ships were used as floating siege batteries.

I received some information today from a very helpful research historian regarding masts and sails and how much certain things weigh in relation to other things, which means I will be revising and expanding on the Ship Construction section of the document.

I thought the trieres/trireme had two masts and thus two sails (at least the later ones did). There's countless images of two-mast triremes, and the Olympias had two.

Talking of construction, one other thing that occurred to me: reconstruction. You might take a ship of one type, and rebuild it as something else (either by design or when repairing storm/battle damage). That might be as simple as turning an aphract vessel into a cataphract by adding decking, but also more complex such as adding a bank of oars to a single or two-decked vessel to increase the number of rowers.

As you noted in an earlier reply, a pentekonter, for example, wasn’t much smaller than a trireme, adding another bank of oars (which would make it higher, but also sit lower in the water due to the extra weight) would double it’s power under oars. Rebuilding it with a broader beam might also allow you to accommodate a second rower on each oar of the top bank.

While it might be complicated and involve compromises, it’s still probably cheaper than building a new ship, and may require a lower level of shipwright skill.

Sorry, I’m just getting back to this - my understanding (although I’ll need to re-read the Olympias trials again) is that the boat mast (the forward mast) did very little to speed the ship up if the mainmast was functioning. It ended up having two functions: it was an emergency mast that would allow sailing if the mainmast wasn’t aboard (i.e. in a combat situation) or if the mainmast broke. Also, when both sails were used, it helped the ship when turning because it could be set for the new angle and catch the wind while the mainsail was being reset.

I do already have rules for a bowsprit that reflect the second use, but I’ll need to modify the rule to allow use of a bowsprit as an emergency sail.

Just to test the construction system, I decided to try out a giant merchantman. It’s loosely based on the Roman grain ship Isis.

Our starting point is that the ship was 180 feet long, over a quarter that in width, and had a cargo hold that was 44 feet deep from the main deck to the keel.

So, to start, we’ll use a 180 foot length and a 3:1 beam, which gives us a rather tubby 180x60 ship, with a 15 foot draught. That’s probably not enough to be 44 feet from the main deck, so we’ll add a second deck to drop the draught to 22.5 feet. The ship has a seaworthiness of 5, and as a giant merchant ship, no rowers will be added. Isis is a 2068 ton ship, with a base capacity of 413,600 stone. Her base shp are equal to her tonnage, which is 2068. Because the Romans used mortise and tenon joining, she’ll be considered a clinker ship. This give +10% shp and +1 seaworthiness, but means rowers or artillery cannot be carried on any deck except the top deck. This means Isis has 2275 shp and a seaworthiness of 6.

At 180 feet, she could have up to six masts, for a total of 13 sails, but that’s far more than what the Romans actually did. Instead, we’ll go for a modest 3 masts and 5 sails. With square sails and the beaminess of the ship, that will require 66 crew to handle the sails. This also gives her a speed of 2 hexes per round when sailing with a fresh breeze (0 modifier) from an aft quarter (also 0 modifier). Given that the base turn rate for Isis is 11 (one 60 degree turn every 11 rounds), we’ll also add a bowsprit (which requires 2 more crew), to improve the turn rate to 10. It’s not much, but it makes her a little less of a wallowing pig. The total weight of masts, sails, and rigging is 5400 stone. Carrying a full spare set of sails and rigging adds another 1800 stone, so the total rig is 7200 stone.

With 68 crew needed to run the ship, an additional 7 crew (captain, navigator, bosun, and 4 spare sailors) are added to make an even 75 crew. At an average of 15 stone weight for a human, the crew weighs 1,125 stone. For the sake of this example, each crew member has 200 stone of personal gear and rations for the voyage, for another 15,000 stone in crew weight. The total crew weight is 16,125 stone.

Adding crew weight plus rig weight, the ship could sail with equipment taking up 23,325 stone, which would allow Isis to theoretically carry up to 390,275 stone in cargo, or about 1950 tons. However, a ship like this would also have marines aboard, and the real Isis also carried artillery on her top deck. These would reduce cargo space accordingly, but it shows the massive amounts she could theoretically carry.

For cost, the hull of Isis alone costs 227,500 gold pieces. The masts cost 36,000 gold pieces. Rigging costs haven’t been figured yet, but I anticipate they’d be somewhere around the cost of the masts, maybe a bit more. A normal crew would be 563 gold per month. So, it would cost approximately 300,000 gold to have the ship built, and a minimum of 563 gold a month to have a competent crew handle her. She can haul large amounts of cargo, but only at a speed of 4 knots in a moderate breeze, and she’ll pretty much only be used between Class I markets because of the amount of cargo she needs to haul to be profitable.