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TNE Only: Formatting marks in the Wet Navy Design Rules on BARD

TheDark

SOC-11
On BARD, there are Wet Navy Design Rules from Terry. It looks like they're mildly adapted from his Challenge articles providing rules for Mega. However, it also looks like when it was copied from the software he was using to whatever BARD uses, some formatting hiccups slipped in. I think I've figured them out, but I'd appreciate any input from people with more familiarity with Terry's work before I save a personal copy for tinkering.

(Hull Volume) x (Wgt Modifier) x (thickness in cm)3D True Wgt

I've figured this one out; wherever "3D" appears, it's supposed to be "=".


5. Note the hull's volume in cubic meters from the Fire, Fusion & Steel Hull Size table.

6. Determine the hull type.20

7. Multiply the hull's displacement tonnage by the

I think this might be a page break? Anyone have any better ideas?

Hull Type Resistance % of Hull Price
Displacing Modifier
Fluid

Deep Displacement 0.9 90% 0.75
Parallel Displacement 0.7 75% 0.85
Curved Displacement 0.5 50% 1.00
Planing 0.3 30% 1.10=09
Hydrofoil (at speed) 0.1 10% 1.50=09
Submerged submersible 0.9 100% 1.50=09
Surfaced submersible 0.5 80% 1.50=09
Submerged submarine 0.3 100% 2.00=09
Surface submarine 1.0 90% 2.00=09

I'm not sure what these are. I thought they might be asterisks, but the symbol reappears in a later table that doesn't have asterisks involved.

The result is the weight of the fluid displaced by the hull.20

9. Compare the weight of the hull with the weight of the displaced fluid. If the fluid weighs more, the vessel will float, if the vessel weighs more, it will sink. In that case, build a larger hull or choose a lighter hull material.

Another 20 in the middle of the text.

Calculate hull resistance-- Use the formula R=3D(=C3WD) x rf where =C3WD is the square root of the hull's displacement multiplied by the percentage of the hull actually in the water and rf is the hull resistance factor found with each hull type in the Hull Types table. The result is R: hull resistance.

If I'm reading this correctly, "=C3WD" should be sqrt(WD) where W is "% of hull displacing fluid" from the Hull Type Table and D is displacement, and the result of that calculation should be multiplied by "resistance" from the Hull Type Table. Also, the 3D is probably a duplicate =

Calculate power needed to reach design speed with fully loaded hull-- Do this with the formula P=3D(RV^2/2)where P is power in kilowatts, R is the hull's resistance calculated in the previous step, and V is the top design speed. If you wish to calculate the power in megawatts divide the result by 1000 or calculate the power needed with the formula P=3DRV^2/2000.

I think the 3D in each formula is the = glitch again, so the formula is either P=((RV^2)/2) for KW or /2000 for MW?

Weight3D ton per meter in diameter of wheel, screw, jet, or tunnel. Volume3D KL/meter in diameter of wheel or screw. KL/ton3D internal hull volume used for power transmission. Cost3D Credits per meter in diameter of wheel, screw, jet, or tunnel.

All of the 3D here are pretty clearly = signs. This is from the notes to the Marine Power Transmission Table.

Sail Power-- The power generated by wind on sails is determined in a standard atmosphere by this procedure:
1. Multiply the wind velocity in kilometers per hour by 0.28 to convert the wind velocity to meters per second.
2. Calculate the power available in watts with this formula. P3D {[(1286)S]V} 0.1
Where P3D power in watts
Where S3D sail area
Where V3D wind velocity in meters per second

Again, all of the 3D should be =.

When the total sail area is determined, calculate the potential speed expected at several wind velocities. Do this by calculating the power generated by the wind at various wind speeds, then calculate the potential speed with the formula: V^2=3DP^2/R where P is force in kilowatts and R is hull resistance.

This formula is based on kilowatts of power modified by the resistance of vessel's hull. Use the formula R=3D(sqrt(WD)) x rf where WD is the hull's20 displacement multiplied by the percentage of the hull actually in the water and rf is the hull resistance factor found with each hull type in the Hull Types table.

A couple more 3D that shouldn't be there, and another 20. I'm more convinced it's a page break or line break in whatever program Terry originally composed this in.

For each point of rowing ability, the rower is able to increase power output by 40% of the basic wattage value. As an example, an individual with Strength 7 (DM+1) and Constitution 7 (DM+1) has two points of rowing ability. Accordingly, the individual's basic wattage value is increased by 2 x 40% or 80%. This means that:

35 basic wattage x 1.83D 63 watts of total power.

Yet another 3D that should be =, and one that's a bit less obvious than usual because it blends into the number in front of it.

Oars weigh 10kg each and cost CR10 each.20

Paddles-- Light water craft may be propelled with paddles. Though this is similar to rowing a vessel with oars, less power is transfered because paddles have no leverage. A paddle will transmit 60% of the power generated by a rower using an oar.20

Paddles weigh 2 kg and cost CR10 each.

More random 20.

2. Detemine the material volume (MV) of the superstructure by the following equation:
MV3D (2x(superstructure height) x (superstructure length + superstructure width) + (superstructure length x superstructure width))/100
The minimum superstructure thickness should be 0.25 cm.

Another 3D.

Sonar is the sea equivalence of Radar. It is replaced by EMS sensors at TL-10+.

Table 7: Passive Sonar
Weight in tons by Tech Level Price=09
Range 5 6 7 8 9 (Cr)=09
3 0.1 0.05 0.03 0.01 0.005 200=09
30 - 1 0.5 0.3 0.01 2,000=09
300 - - 10 5 0.5 20,000=09
3,000 - - - 10 1 200,000=09
Power (MW): Weight/5
Volume (m3): Weight=D72
09
Table 8: Active Sonar
Weight in tons by Tech Level Price=09
Range 5 6 7 8 9 (Cr)=09
3 2 1 0.5 0.01 - 5,000=09
30 - 20 10 5 0.5 50,000=09

Power (MW): Weight/5
Volume (m3): Weight=D72
Variable-depth sonar is available beginning at TL7, costs 150%
as much as normal sonar, and has a volume equal to Weight=D73.=09

I have no idea with this table. It looks like something went horribly wrong with the formatting.

Torpedoes-- Torpedoes are designed like submarines, at TLs below 5, they are unguided, at TL5-7 they are typically wire guided, and at TL7 and up they are typically target memory or seeker guided. Torpedo tubes are designed like Space Missles, except with the correct type of control system.20

Yet another random 20.

Pressure Hull and Maximum Depth-- A sub's max depth is 15=D7armor value.

The =D7 also appeared in the sonar table. I'm not sure what it's intended to be.

Helicopters, VTOL aircraft and grav vehicles can operate off any vessel with a clear deck area big enough for wingspan or rotor diameter=D71.5, or length=D71.5 for grav vehicles.

More =D7.

Table 10: Aircraft Catapults

TL Type Mass Length Cost Capacity
(tons) (m) (MCr) (tons)
=09
5 Gunpowder turntable 5 20 0.05 3=09
6 Hydraulic turntable 10 30 0.1 8=09
6 Hydraulic fixed 10 30 0.1 8=09
6 Large hydraulic fixed 15 50 0.3 13=09
7 Steam fixed 40 100 0.8 35=09

More =09, and (I think) the last unusual symbols in the document.
 
The rules I have are in Challenge 53 and 54 - a lot of these were answered already.

For calculate hull resistance: use the formula R = square root of (D times rf) where D is the square root of the hull's UCP displacement and rf is the hull resistance factor found with each hull type in the hull types table. The result is R: hull resistance. So as written it's a square root of a square root.

For Calculate power needed to reach design speed with fully loaded hull:

P = (R V V) / 2, or R is the hull's resistance calculated in the previous step, and V is the top design speed. (Yes that is V squared) If you wish to calculate the power in megawatts, divide the result by 1000 or calculate the power needed with the formula P = (RVV) / 2000

Active Sonars & Passive Sonars are a bit different here -

Passive sonar power requirement (Mw) = weight in tons x 1
volume = weight in tons x 2

Active sonar power requirement (Mw) = weight in tons + 1
volume = weight in tons x 2
 
The rules I have are in Challenge 53 and 54 - a lot of these were answered already.

For calculate hull resistance: use the formula R = square root of (D times rf) where D is the square root of the hull's UCP displacement and rf is the hull resistance factor found with each hull type in the hull types table. The result is R: hull resistance. So as written it's a square root of a square root.

For Calculate power needed to reach design speed with fully loaded hull:

P = (R V V) / 2, or R is the hull's resistance calculated in the previous step, and V is the top design speed. (Yes that is V squared) If you wish to calculate the power in megawatts, divide the result by 1000 or calculate the power needed with the formula P = (RVV) / 2000

Active Sonars & Passive Sonars are a bit different here -

Passive sonar power requirement (Mw) = weight in tons x 1
volume = weight in tons x 2

Active sonar power requirement (Mw) = weight in tons + 1
volume = weight in tons x 2

That helps a lot for figuring out authorial intent. Looking at the ASCII table that AnotherDilbert linked, 7 is a bell, so that the volumes for both passive and active are "Weight*2" and variable-depth is "Weight*3". That seems to fit roughly with the MT table, and it also would mean the submarine and VTOL pad formulas are 15*armor value and 1.5*wingspan/diameter/length respectively. I suspect the power requirement for sonar may have been changed to be more similar to other sensor systems in FF&S.

For the hull resistance, it looks like it's a modified formula, using SQRT(d*w)*rf instead of SQRT(SQRT(d)*rf). I'm not sure why it would need adjusting, but I'll keep both formulas in mind when I play around with the system.

The power formulas for ship's speed are the same, although the change to hull resistance means R will have different values.

Thanks to both of you for the assistance in figuring out what the original text would have been.
 
Some quick and dirty, but fairly accurate rules of thumb for warship design.

The hull weight for ships up to battle cruisers without heavy armor is 50 percent of the displacement of the ship. For battleships and battlecruisers, the hull with weight 40 per cent of the displacement, leaving you 60 per cent for armament, armor, and propulsion. That comes from Norm Friedman's Battleship Design and Development 1905 to 1945.

If you are talking cargo ships, the hull weight will depend on material and how much power are you putting into the ship, along with where will it be sailing. The North Atlantic is far harder on ships than the Mediterranean.

Unless Terry updated his propulsion scheme, he does not allow for volume and weight of boilers for steam power plants. I would strongly suggest that you take a look at some cross-sections of warships to get a better understanding on the amount of volume taken up in the hull for the propulsion system.

Aircraft catapult Tech Levels. The U.S., the U.K., and Japan were all using hydraulic catapults on their aircraft carriers by the start of World War 2, while black powder catapults were used on battleships and cruisers. Both types should be Tech Level 5. The British introduced the steam catapult in the early 1950s for launching the heavier jet aircraft, and the U.S. quickly copied the idea. Steam catapults should be Tech Level 6.

You might want to take a look at Edward Attwood's books on warship design on archive.org to get a better idea as to what goes into designing a warship. He has excellent schematic plans and also some nice power curves on the power required for a given hull at different speeds. Norm Friedman's books on warship design also would be extremely useful in terms of seeing what a warship looks like in cross-section. Conway's World Warship series also would give you a good idea of what is possible on at given hull size.

If you want to find a good source for oar power, I would recommend Admiral William Rodgers two books on naval warfare under oars. He does underestimate the speed of the Greek and Roman triremes, but his data for the big Renaissance galleys is dead on. If you want it, I will try to transcribe it for you.

There is also the following books on Project Gutenberg that might be useful.

Ocean Steamships by a range of authors. A lot of information and drawing on the development of the steamship. http://www.gutenberg.org/files/54136/54136-h/54136-h.htm

American Merchant Ships and Sailors by Willis Abbott. A lot of information on sailing ships and the various types.
http://www.gutenberg.org/files/15648/15648-h/15648-h.htm

Two Centuries of Shipbuilding By the Scotts at Greenock. Scotts was one of England's leading shipbuilders during the 1800s of a wide range of ships.
http://www.gutenberg.org/files/54667/54667-h/54667-h.htm

Farthest North Being the Record of a Voyage of Exploration of the Ship 'Fram' 1893-1896 Vol. I by Nansen. The "Fram" was probably the first purposely designed research ship, and is still extant as a museum. Aside from the drawings, there is an excellent discussion of its building.
http://www.gutenberg.org/files/30197/30197-h/30197-h.htm

There is also a lot of naval architecture books on archives.org if you are interested. I would be more than happy to steer you in the right direction if you wish. One other thing, do not pay a whole lot of attention to the hull rules for Wet Navy, as hull thickness was far different from what is given.

His manning rules are also way out of line.
 
Active Sonars & Passive Sonars are a bit different here -

Passive sonar power requirement (Mw) = weight in tons x 1
volume = weight in tons x 2

Active sonar power requirement (Mw) = weight in tons + 1
volume = weight in tons x 2

Why do Passive and Active sonars have the same power requirement? Passive is simply listening for enemy sonar pings, active is generating the pings. There should be a major difference in power requirements.

Passive sonar, in the audible ranges, can be as simple are an unpowered directional hydrophone. Also, does he make any distinction in sonar ranges for frequency, with the longest range being given by the lowest frequency?

As for hull resistance, that is heavily dependent on how long between docking to clean the ship's bottom. Six months without cleaning in tropical waters might cost you a couple of knots of speed, along with an increase in power for lower speeds. It is also effected by how heavily loaded the ship is, and how many propellers shafts are used, as well as the shape of the stern.

For more discussion of the MegaTraveller Wet Navy design issues, those interested can check out the following thread.

http://www.travellerrpg.com/CotI/Discuss/showthread.php?t=27245
 
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Why do Passive and Active sonars have the same power requirement? Passive is simply listening for enemy sonar pings, active is generating the pings. There should be a major difference in power requirements.

There is. If you bothered to read the tables, you'd see a TL5 passive array with 3 km range is 0.1 dTons and thus 0.02 tons, while an active array with the same range is 2 dTons and 0.4 tons, or 20 times larger. That, however, would require an honest evaluation of the data at hand rather than hasty attacks on the work without bothering to determine if they're accurate.

As for the rest of your screed, this is not Phoenix Command and we don't need 476 charts to determine if stepping on a nail penetrates the sole of a boot. On the spectrum of technical simulationism vs. playability, you're off the deep end of simulationism.
 
There is. If you bothered to read the tables, you'd see a TL5 passive array with 3 km range is 0.1 dTons and thus 0.02 tons, while an active array with the same range is 2 dTons and 0.4 tons, or 20 times larger. That, however, would require an honest evaluation of the data at hand rather than hasty attacks on the work without bothering to determine if they're accurate.

As for the rest of your screed, this is not Phoenix Command and we don't need 476 charts to determine if stepping on a nail penetrates the sole of a boot. On the spectrum of technical simulationism vs. playability, you're off the deep end of simulationism.

Okay, you are on your own.
 
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