Bk2 fire control vs Bk5 turret mass

[Matt123]

I am looking to create an easily explained decision between using Bk2 hardpoints/fire control and Bk5 hardpoints/turrets in CT ship design.


Book 2 Starships

Fire control equipment is required if weaponry is to be installed. Each installed turret requires one ton of displacement committed for the installation of fire control equipment. Bk2 p.14

Ok. So if I want to allocate a hardpoint, but not install a turret, I do not need to install fire control. In effect I could allocate a ton from cargo space at a later date. No decision on fire control is needed at the design stage.

Any ship may have one hardpoint per 100 tons of ship. Designation of a hardpoint requires no tonnage, and costs Cr100,OOO. Hardpoints may be left unused if desired. Bk2 p.15

In addition, Bk2 turrets and weapons do not add mass. They just require the 1ton of fire control mass that is already allocated (or taken from cargo space)

Book 5 High Guard

The ship design and construction system given in Book 2 must be considered to be a standard system for providing ships using off-the-shelf components. It is not superceded by any system given in this book; instead this book presents a system for construction of very large vessels, and includes provisions for use of the system with smaller ships. Bk5 p.18

Included mostly to highlight the additive nature of Bk5. It doesn't replace Bk2 systems, it adds new options.

Hardpoints require no tonnage; but turrets themselves (when installed) do require tonnage. Bk5 p.30

I interpret this to mean that in Bk5 the fire control in included with the turret.

Other stuff

Bk 2 hardpoints cost 0.1MCr and require internal tonnage if and only if a turret is installed. Adding a turret does not increase ship size, it deducts from available internal space.

Bk5 hardpoints are free and do not use internal tonnage, tonnage is added when the turret is added. Adding a turret increases ship ship and if not considered at design time may impact ship performance. When designing to a ship size, this will manifest as deducting from overall available space, in effect the design loses the space immediately, as it was never internal in the first place.

Fire control is fixed at 1ton in Bk2 which only has lasers, missiles and sandcasters available.

In both cases custom hulls cost 0.1MCr per ton, as do standard hulls of size 800tn and 1000tn. Both designs can chose not to install hardpoints, but only Bk2 provides an incentive due to the hardpoint cost.

Conclusions (tentative)
This is where I enter potentially un-safe territory... The above is quite convoluted and confusing, in addition there might be other stuff to consider. But assuming there is nothing else, does this capture the essence?

Bk2 fire control can only be used with Bk2 weapons (laser, missile, sandcasters).

Bk2 fire control, being internal has the benefit of allowing un-used fire-control space to be used for other purposes (eg: cargo), but at the cost of 0.1MCr per hardpoint.

Thoughts, comments?

Cheers!

 

[BillDowns]

Well, Matt, I have never been quite sure what was intended by those passages about "fire-control" in LBB2. And, quite frankly, I do not believe the statement about LBB5 not replacing LBB2. The two systems are too incompatible for that statement to be true, IMO.

In fact, ship weapons systems require a lot of space; I guess you can lump it under "fire control". But allow me to throw out real-world example from the USS Ticonderoga. Here's a picture: http://www.seaforces.org/usnships/cg/CG-51-USS-Thomas-S-Gates-Dateien/image017.jpg

Obviously, the weapon housing has to take up space. Now, refer to the pic. See those two white dishes on top of the superstructure? Those are the paired AN/SPG-62 Fire Control Radar systems for the Mk26 twin missile launcher. Above them is a white, squashed looking dome which is the AN/SPQ-9 Gun Fire Control Radar. These radars feed respectively, the Mk99 Fire Control System and the Mk86 Gun Control System. In turn, these both send data to Aegis.

These systems had equivalents in all naval vessels prior to publication of Traveller, and all were documented in Jane's, which certainly could be found in Chicago. So, what did GDW mean in their books? I have no freaking idea....

Both of the fire control systems, would be subsumed in the Traveler computer, with Predict, Launch, Target, the other Offensive programs taking that role.

If it was up to me, I would say that the turret should take a ton (minimum), and the fire control radars at least a ton each. So for a typical Far-trader with two mixed turrets, each turret is 1 ton. Two fire control radar systems - one for missile and one for laser - then again for each turret to allow each missile launcher and each laser to be used in a turn, you would then have 5 tons taken up in weapons & fire control. And, of course, that's with the very soft sci-fi aspect of how small those are.

Perhaps the thought is that civilian ships would use the general sensors and not have fire control illuminators but LBB5 doesn't have fire control illuminators, either.

Be wild - do what you want!

 

[BillDowns]

Oh, I forgot the gunners' consoles - 1 ton each, 2 required.

One time I did estimate the requirements for a Mk45 Mod 0 = 10 tons, 5 external over 5 internal. and for a Mk75 = 6 tons, 3 over 3. Just for comparative purposes...

 

[simonh]

The wording of the Book 2 and Book 5 rules are different, but the end result is the same. You need to have 1 dton of space free to install and operate a turret.

I do not agree that you can allocate cargo space to fire control after the fact. The way I read 'committed for the installation of fire control equipment' is that it has to be committed at design time, otherwise there is no commitment. I think there are design constraints on the positioning of fire control equipment relative to the turret, power and data link installation, access to the hull for sensor pods, etc that make it impractical to use space committed to fire control as cargo space. I would allow stuffing some gear into the unused space if really necessary, but less than half a dton's worth.

Oh, I forgot the gunners' consoles - 1 ton each, 2 required.

Each gunner's console takes up 14 cubic metres of space? That seems like rather a lot.

Bear in mind that 5 dtons for your far Trader loadout is about the size of a big-ass 40' hi-cube shipping container, which can load up to 30 metric tons. Turrets fill the role of light armaments for civilian or paramilitary craft, the big guns are really barbettes or bay weapons.

Personally, I'd probably have required 1 dton per turret, plus 1 dton of fire control. That seems a pragmatic balance. But there's enough investment in the 1 dton per turret rule (whether as actual turret or fire control) in terms of existing designs and player expectations that I don't think it's worth the trouble changing. The design system is crude enough in it's approximations that if you want to depict or imagine them as being somewhat larger, in the context of the system as a whole that's well within the wiggle room the system allows for.

Simon Hibbs

 

[whulorigan]

Well, Matt, I have never been quite sure what was intended by those passages about "fire-control" in LBB2.

I eventually came to the conclusion that what the 1 dton for fire-control in Bk2 was referring to was that you need to set aside (ahead of time) space in the hull for a gunner's couch and gunnery station for the crewman to man the weapon, should weapons eventually be installed. In a Bk5 High Guard design (typically Naval), the Fire Control could probably be considered to be integral to the much more sophisticated command and control systems (i.e. a Gunnery Officer on the bridge and or Gun/Fire Control Stations located elsewhere in the hull, or otherwise integral to the weapon system being installed).

 

[BillDowns]

Duh! :coffeegulp:

I just realized, you are probably asking for your Ship Builder, right? In that case, like already posted, the end result is a ton and has to be set aside from the get-go.

 

[Matt123]

I just realized, you are probably asking for your Ship Builder, right?

yep, but hearing views that are different to mine is interesting, as was your tangent on real life warships. I'm house painting for a couple of days, I'll check back in afterwards and re-read the relevant sections of the rule books before figuring out how to code this. Cheers.

 

[simonh]

An alternate model for a Traveller turret.

Rapier air defence system.

Those missiles are about 2m long. The whole thing, including tracking system, can't be more than a dton. The Rapier 2000/Jernas system shown further down is even more compact, half a dton or less with the optical tracking module.

Now, a Rapier isn't an anti-shipping missile but if it did hit a ship they'd at least notice it, and it's not as if Traveller missiles are one-hit-one-kill even against something like a Type-S.

Simon Hibbs

 

[samuelvss]

An alternate model for a Traveller turret.
...Rapier air defence system[/URL]. Those missiles are about 2m long. The whole thing, including tracking system, can't be more than a dton. The Rapier 2000/Jernas system shown further down is even more compact, half a dton or less with the optical tracking module.

Well, as a SWAG, dealing with non-existent and essentially ill-defined future tech, this puts us in the ballpark. (e.g higher tech, bigger target, up to 9 missile vs 4, much greater ranges). While I don't recall anything about "gunners' consoles in canon, under the small craft rules, a couch is .5 dton.

I always imagined the Bk2 reserved space as part in, part out. If I build a 800 dton ship, and designate 8 (empty) hardpoints, I reserve the 8dtons. Presumably some of the 8 dtons is on the outside of the ship, for that portion of the turret that protrudes. Even if we call it a quarter, if I then added the turrets, and those 2dtons were not included in the 8 dtons, I would then have a 802 dton ship.

Since Bk5 ships were typically military, the design it now, add it later was not such an issue, so they just charge you for the turret. I always read it the same, as the effect was essentially the same: you effectively have to pay upfront in space, if not money for the hardware.

As to fire control, my biggest hitch with Bk2/Bk5 incompatibility was in designing batteries: 8 gunners on a Type C vs 2 is huge.

 

[BillDowns]

An alternate model for a Traveller turret.

Rapier air defence system.

Those missiles are about 2m long. The whole thing, including tracking system, can't be more than a dton. The Rapier 2000/Jernas system shown further down is even more compact, half a dton or less with the optical tracking module.

Simon Hibbs

Yes, that looks like a nice unit for ground-pounders

Here's a Sea Sparrow Mk25 launcher - 8 missiles. The missile is 3.6 m, so that launcher looks around 4m x 4m and about 5m high, so about 3 dtons. You could apply some hand-wavium and call it 2.

 

[simonh]

Yes, that looks like a nice unit for ground-pounders

Here's a Sea Sparrow Mk25 launcher - 8 missiles. The missile is 3.6 m, so that launcher looks around 4m x 4m and about 5m high, so about 3 dtons. You could apply some hand-wavium and call it 2.

Serious bit of kit.

Rapier is a bit long in the tooth nowadays, but still in service. We used them in the Falklands conflict. I remember watching them in action on the TV when I was 16.

Simon Hibbs

 

[BlackBat242]

While I don't recall anything about "gunners' consoles in canon, under the small craft rules, a couch is .5 dton.

Which is specifically stated to include a life-support system with at least 12 hours capacity. A gunner's console in a ship doesn't need the LS, as that is included in his stateroom tonnage.

 

[Matt123]

Ta for the input guys. There was only one area of contention, whether Bk2 fire-control has to be committed to at the design stage. I implied no, but others suggest yes and that the space may not be usable for much else. Re-reading bk2, immediately after the passage I quoted is this next paragraph (both paragraphs shown).

Fire control equipment is required if weaponry is to be installed. Each installed turret requires one ton of displacement committed for the installation of fire control equipment.

Original design plans for ships often include reserve tonnage for later use in installing fire control equipment, or for upgrading computers. Bk2 p14

Which I think supports the notion the space has to be committed to.

But what can reserve tonnage be used for in the meantime? I am of the view that the fire control itself comes with purchasing the turret. Both bk5 and bk2 only use up displacement tons on installation of a turret, the only difference is where the fire control is located --- outside the hull in the turret or inside the hull. This interpretation leaves reserved fire control space empty until a turret is purchased with its 1 ton displacement of fire control.

I would apply the same logic to reserved computer space (it is empty until you purchase and install a computer). As a ship designer, I would place this unused reserve space next to cargo space where it can be utilized.

However, Bill, Simon & Samuel have variations on, it is reserved and therefore not usable space for other purposes in the normal sense. While whulorigan interprets it as space reserved for a future gunners station. It is looking like I am alone in my liberal interpretation of reserved!

So... two options for the ship builder.

(A) Bk2 fire control is reserved at design time, but considered empty until it is used as such. Meaning it can be used for other purposes (eg as cargo space). Cargo capacity must be sufficient to allow for representing the reserved space and should be suitably noted as such.

​

(B) Bk2 fire control is reserved at design time and for practical purposes, although not yet used, is not usable for other purposes. In effect this means a hardpoint item has both a cost and a 1 ton displacement.
​

I will implement option B as I am out-voted by some 4-1 which is a sizeable margin! Arse...

 

[Condottiere]

Specific to fire control, it would depend if the ship had been designed as a warship, had a paramilitary function, was intended to be an armed civilian craft, self defense systems were intended, or if it was an after thought.

Simply deducting it from cargo may cause accessibility, supervision and security concerns. That's why a turret with a locked door was such a simple solution.

 

[Matt123]

lol... 5-1

 

[Matt123]

Option B is implemented.

 

[Condottiere]

On reflection, I think dummy fire control consoles would be installed, regardless of whether the turrets are armed.

After all, Captains need some place to hide their stock of forty year old Scotch.

 

[elbmc1969]

I vote for option A, but only in the sense that there's an empty tub where the turret goes ... You can stash smallish items there.