TL4/5 Torpedo Launchers

[Skaran]

I have a low tech world, roughly TL4-5 on the verge of war and was wondering how you would design this sort of system as found on WW1 and II destroyers.

If it was just a single torpedo I assume that you could use a pintle mount since a torpedo masses 500kg but what about these sort of banks. They are capable of being rotated so are not fixed mount. Looking at the base it still looks like a pintle mount. Should I just assume that, in the case of this installation it is actually 5 pintle mounted torpedoes joined together?

 

[Reisender]

I have a low tech world, roughly TL4-5 on the verge of war and was wondering how you would design this sort of system as found on WW1 and II destroyers.
View attachment 1925
If it was just a single torpedo I assume that you could use a pintle mount since a torpedo masses 500kg but what about these sort of banks. They are capable of being rotated so are not fixed mount. Looking at the base it still looks like a pintle mount. Should I just assume that, in the case of this installation it is actually 5 pintle mounted torpedoes joined together?

I guess you are referring to the construction rules in the Vehicle Handbook.
To me it looks more like a turret mount rather than a pintle mount. Since it does not offer the protection of a complete turret you might want to tweak it a little bit in regards to cost and space.

 

[AnotherDilbert]

Vehicle Handbook, p37:
A pintle mount consumes no Spaces and costs Cr250, while a ring mount costs Cr750. A weapon of up to 500 kg may be attached to them.

A torpedo is 500 kg (2 Spaces), so technically max one on a pintle mount.

A Small Turret can hold 4 Spaces worth of weapons, so is not large enough.

A Large Turret would technically be required.



With a loaded weight of ~18 000 kg (40 000 lbs), is should be about 72 Spaces...
https://maritime.org/doc/destroyer/ddtubes/index.php

 

[Skaran]

I suppose a pintle mount could take a single Vehicles Handbook torpedo, a small turret a pair and a full turret as many as required but space for crew need not need to be included in the turret as it does not enclose anything other than the tubes. 72 spaces... If you use the rules as written for a large turret we get 4 spaces within the vehicle, in this case a ww1 or ww2 destroyer with a quintuple launcher of 5 torpedoes occupying 10 spaces on top of a deck. The mass of the torpedoes in the Vehicle Handbook is 500kg (1102 pounds) the booklet you referred to gives a weight of the torpedo as 3185 pounds about 1445kg to Mongoose torpedoes are about a third the mass of the Mk 14 real thing. The actual mass of the turrets, launch equipment etc. is ignored in Vehicles Handbook.
Then I need to work out some bigger guns for my TL4 cruisers and battleships.

 

[AnotherDilbert]

Then I need to work out some bigger guns for my TL4 cruisers and battleships.

CSC, p167 has something to start with:



Take something like the Heavy Cannon, detune it to lower TL, a bit bulkier, and better range?


4 tonnes for a heavy gun would be something like 5"/128 mm gun.
A 15"/38 cm gun would be something like 100 tonnes (400 spaces).

 

[Skaran]

This is how my version of the Acasta class destroyer is currently looking. I used the Light Gun to represent the 4 inch and a medium autocannon to represent the 40mm pom pom as originally fitted. I used the section in High Guard to lower the tech level. The heavy cannon at TL7 I could use at TL5 using the TL adjustments but TL4 is a step too far. It would be interested to know if these weapons were actually designed or made up.

Acasta class torpedo boat destroyer​

Terra/Sol/Solomani Rim 1827​

The Acasta class torpedo boat destroyer, later destroyer, served in Terra’s first world war and by later standards is a tiny, cramped vessel.

ARMOUR​
FRONT	3	TL	4
REAR	3	SKILL	SEAFARER (OCEAN SHIP)
SIDES	3	AGILITY	-6
		SPEED (CRUISE)	SLOW (VERY SLOW)
		RANGE (CRUISE)	2000 (3000)
		CREW	70
		PASSENGERS	0
		CARGO	20.75 tons
		HULL	1600
		SHIPPING	200 DISPLACEMENT TONS
		COST (INITIAL) COST (SERIES)	CR. 5,159,500 CR. 4,643,550

TRAITS​		EQUIPMENT AND WEAPONS​
	Autopilot (skill level)	-	Bunks x70, Fire Extinguishers, Freshers x2, Large Fresher x1, Small boats x2 Large Turrets (Early prototype light guns, inaccurate, increased size) x3, Small Turret (Early prototype medium autocannon, inaccurate, increased size) x1, Pintle Mount (Single torpedo, left side) x1, Pintle Mount (Single torpedo, right side) x1
	Communications (range)	-
	Navigation (Navigation DM)	-
	Sensors (Electronics (sensors) DM	-
	Camouflage (Recon DM) Stealth (Electronics (sensors) DM	- -
			Crew allocated 2 spaces per person

WEAPON	RANGE	DAMAGE	MAGAZINE	MAGAZINE COST	TRAITS	FIRE CONTROL
Light Gun	9	8D	1	Cr 200	AP 5, Blast 10, inaccurate Increased size	-
Medium autocannon	1	8D	100	Cr 1500	Auto 3, Inaccurate, Increased size	-

WEAPON	TL	RANGE	DAMAGE	TONS	SPACES	COST	MAGAZINE	MAGAZINE COST​	TRAITS
Torpedo	4	1​	1DD​	0.5​	2​	Cr3000​	1​	-​	AP 10, One use. Smart

 

[AnotherDilbert]

Looking good.

The TL-5 Light Gun could get away with a single disadvantage to make it TL-4?

 

[Skaran]

The Light Gun is TL6, the Light Howitzer is TL5. I could use that instead of the light gun giving a somewhat reduced range.

While I am playing round at TL4/5 does anyone have an idea of the true stats for the Hargrave H-6 submersible boat? It is given a cost of 483,000 credits and a shipping space of 28 tons. At 0.5 tons per space this means 56 spaces. This makes it a heavy submersible with a base cost of 100000 credits per space or 5600000 for this alone.

 

[AnotherDilbert]

The Light Gun is TL6, the Light Howitzer is TL5. I could use that instead of the light gun giving a somewhat reduced range.

Sorry, I used CSC'23.

While I am playing round at TL4/5 does anyone have an idea of the true stats for the Hargrave H-6 submersible boat? It is given a cost of 483,000 credits and a shipping space of 28 tons. At 0.5 tons per space this means 56 spaces. This makes it a heavy submersible with a base cost of 100000 credits per space or 5600000 for this alone.

Agreed, that is obviously wrong.

 

[Skaran]

Are there many differences in TL in the revised Central Supply Catalogue as I have not got that one yet only the older one.

 

[MongooseMatt]

If it was just a single torpedo I assume that you could use a pintle mount since a torpedo masses 500kg but what about these sort of banks. They are capable of being rotated so are not fixed mount. Looking at the base it still looks like a pintle mount. Should I just assume that, in the case of this installation it is actually 5 pintle mounted torpedoes joined together?

This is an excellent question.

I think, if it were me, I would create a whole new weapon (and perhaps go to town on it, with 3, 4 and 5 tube designs, plus a range of torpedo types that escalate with TLs beyond that of the tubes themselves).

I would then (and this is possibly going too far unless you are planning a significant wet navy adventure/campaign) create new torpedo rules, perhaps building upon spacecraft missile salvo rules.

But that is just me

Maybe something to look at in a Vehicle Handbook Update!

 

[Annatar Giftbringer]

That’s one way to do it, totally not excessive!

Seriously though, you do make a good point there Matt, we do not and should not feel limited or constrained by published material.

If anything is available that fits what you want and need, of course use it! But if nothing suitable exists, create it!

Use the Robot Handbook, CSC, HG, VH and so on as inspiration and guide, use their design processes to help you, but dare to go beyond them if needed.

It’s a game, and it’s your game.

 

[AnotherDilbert]

Are there many differences in TL in the revised Central Supply Catalogue as I have not got that one yet only the older one.

I haven't checked systematically, but I don't think there are any major differences.

 

[Reisender]

I hope that these are what we are talking about:

Wikipedia: Acasta Class Destroyer

 

[Skaran]

Yes, that is the vessel used as a base. The following class is similar but had two twin torpedo launchers on the centreline. My players characters are currently stuck on a TL4 world on the verge of a global war. The various nations are taking sides and all that is wanted is a trigger.

 

[Condottiere]

Leaving aside naval tactics, topside torpedo tube launchers increased in number from one to five, weight and size would indicate a hard point, and possibly an option to reload onboard.

Also, possibility for a pop up, in the sense that they could be emplaced behind a panel.

Centrally embedded, could be launched on either side.