[Proto-Traveller] Starship Design

[Mithras]

This relates to the Proto-Traveller thread-project of old (http://www.travellerrpg.com/CotI/Discuss/showthread.php?t=10648&highlight=prototraveller). But it came up as an idea from my threads on a small-ship universe, and using Book 2 starship combat. Both threads here:

http://www.travellerrpg.com/CotI/Discuss/showthread.php?t=25623
http://www.travellerrpg.com/CotI/Discuss/showthread.php?t=25689

So, if we assume that Traveller started and ended at Books 1-3, why are starships designed the way they are? There are some issues that come up, and get 'fixed' by High Guard, MegaTraveller and Mongoose Traveller, but here we must assume they aren't fixes, they are add-ons that aren't in this Proto-Traveller universe. Generally they revolve around the following.

Size
Ships have a maximum size of 5,000 tons. Why? Possible answers include: 5,000 tons is the biggest hull you can create a jump field around. What about non-starships? Perhaps 5000 tons is the biggest hull you can create a gravity-drive field around ... That lets us have much bigger 'stations' without manoeuvre drives.

Armour
Ships, even military ships like the Types T and M and some of bigger military ships in the Alien Modules, have no armour. Why? Are they already armoured? The toughness of bulkheads outlined in Traders & Gunboats: Supplement 7, suggests this. Could there be any other reasons?

Weaponry
Small homing missiles, beam & pulse lasers are the advanced weaponry of the age, right up to TL 15. Reading the JTAS article Airstrike (JTAS 17,33), effects of a laser hit seem devastating, it "totally destroys all life and structures in a 50m radius." This seems OK, we can live without fancy particle weapons here, can't we? However, I think it was Magnus THornwood who found the big problem with Bk 2 construction, was building battleships of 5,000 tons that actually looked like battleships.

Let me expand. He found that a 5000 ton cruise liner with 50 triple turrets and a 5,000 ton 'battleship' with 50 triple turrets have very little to separate them when it comes to a fight. That can't be right! And what is inside a 5,000 ton battleship? There won't be that many crew, or fuel or ships. Shouldn't it be full of weapons? THe obvious answer is to pack in bay weapons from High Guard. That would work. But in a Proto-Traveller universe we want to try and 'work with what we've got', so to speak.

My answer is: there are no battleships. Looking at my passenger liner example, they aren't feasible. If your going to build this 5,000 ton monster, you'd better fill it with something to give it teeth!

I propose that in a Proto-Traveller universe there are only two main types of 'big ship' (3000/4000/5000 ton vessels). These are the carrier, with a BSG-style complement of attack ships to be deployed once in-system (a spaceborne aircraft carrier). The other type of ship is an assault carrier, a spaceborne helicopter or Marine Corps assault carrier. This has tons of troops, ground vehicles, command centres and landing craft.

Could there be other reasons? As a final note to the liner or battleship problem, it isn't just weapons that make a warship, I know. A high rated computer and high rated manoeuvre drives are also needed, also some redundancy.

That's all I have for know (I'm sure there was something else, I think I got sidetracked by battleships and cruise liners!). This is a bit of a thought experiment, but any rationales would certainly help me cement my Proto-Traveller game!

THanks!

 

[robject]

Some possibilities to toss around.

We also know that the ANNIC NOVA's exterior-facing airlock bulkhead thingies were extremely tough, further hinting at armor. It might be worth thinking about to have the ship's Mission grant it a particular advantage.

By Mission, I of course mean ship "Type". Type might imply an ordered priority for that design, and a latent benefit.

Something like...

"A"/"R": trader/merchant. payload primary.

"C": cruiser. equal armor and guns primary.

"E": escort. guns and maneuver primary?

"L": lab. payload and support craft primary.

"M"/"F": liner/freighter. payload and jump primary.

"P": corsair. guns and maneuver primary.

"S": scout. sensors primary?

"T": patrol. guns primary.

"X": express. jump primary.

"Y": yacht. payload primary.


Primary elements get a purchase discount, maybe. So traders get staterooms at half price. Patrol ships get guns at half price. Etc.

 

[steventirey1985]

A possible solution to the 5000 ton cruise ship having the same number of turrets as the 5000 ton battleship - don't give the cruise ship all of those turrets. Really, why would a civilian vessel carry that many turrets? Sure it could, but there is no need. So limit civilian designs to say, half the number of turrets at most, and even that may be pushing it. Maybe limit them to 1/4 the number of turrets. Not as a strict limit, but as a general guideline (they could still have more turrets then that, but the typical civilian ships don't).

 

[shadowcat20]

Good ideas.

Considering the merchant Vs battlewagon,

A. Economics....How much space does 50 turrets, gunners, and berthing eat up that could be used in a more cost effective manner? Keep in mind if I remember right batteries are a HG invention so you need 1 gunner per turret. Warships are paid by tax payers, merchants have to make their own paycheck.

B. In a small ship universe weapons hit harder and there is no armor. So this means warships are more likely to be carriers with lots of guns. The fighter support space, hangers, crew berths, and support personel spaces again will take up room that merchants would use for passengers and cargo.

SO, same hull but where merchants have cargo and passenger berths, warships have fighters, more guns, gunners, pilots, hanger crew, and marines for boarding actions.

A merchant COULD have 50 turrets, but will go broke quickly.

C. Jump speeds are computer sensitive so why not fire control? Say 10 turrets per computer program. More turrets mean more targeting computers running software to aim them. Again more space lost for merchants.

I still have book 2 ships be civilian tech and HG stuff is top secret Navy tech in my Traveller Universe. Getting a energy weapon or screen is possabe but good luck if you get caught.

Also smaller ships may mean higher cargo prices as there are no Bulk carriers to drive prices down.

Just my 2 credits,

 

[aramis]

Ship size is VERY straightforward...

Since drives are limited in SIZE by TL, the biggest ship buildable is also limited by what can be driven by the biggest drive.

Remember: TL 9 is drives A-D only... WHich means an 800 Td limit...TL 15 is drives A-Z, and a Z drive can drive a 5000Td hull.

As for why the drive size limits, if we presume that Jump and Maneuver drives both have some size-limited-by-production-tech component that has to be a singular unit rather than multiple smaller ones... call it a gravity mirror or some such technobabble... and the limit on that item is the limit on drive sizes.

I'm minded of the Necklin Rods in the Vorkosiverse. Always a pair, always a single piece each.

 

[aramis]

Ship size is VERY straightforward...

Since drives are limited in SIZE by TL, the biggest ship buildable is also limited by what can be driven by the biggest drive.

Remember: TL 9 is drives A-D only... WHich means an 800 Td limit...TL 15 is drives A-Z, and a Z drive can drive a 5000Td hull.

As for why the drive size limits, if we presume that Jump and Maneuver drives both have some size-limited-by-production-tech component that has to be a singular unit rather than multiple smaller ones... call it a gravity mirror or some such technobabble... and the limit on that item is the limit on drive sizes.

I'm minded of the Necklin Rods in the Vorkosiverse. Always a pair, always a single piece each.

 

[Rigel Stardin]

Checked my copy of Jane's Warship Recognition Guide, Aircraft carrier (largest ship I could find 91,000 + tons) have approximate 100 fighter/support craft. So in a small craft universe, you could say 1 fighter per every 1,000 tons. This would include, hanger space, fuel, spare parts, support equipment and living space for the support personal. You charge 1 hardpoint per fighter to limit the number of weapons. I was surprise to learn that there was only 4 weapon systems on a modern aircraft carriers.

At a glance, other modern armed vessel have heavy weapons (Ship destroying weapons) 4 to 6 weapons system. 300 to 500 hundred tons per weapon systems (again this is for support equipment and living space). If we advance that into Traveller we wouldn't have 500 turret Battleships but 100 turrent battleships.

Damage for these "big guns" could be 10% of the tonnage. Battle wouldn't last for forever and you'd hurt the other guy.

This has always been my major sticking point with the combat system presented in Traveller. The designers never linked damage to weapon tonnage. Don't get me wrong, I like the easy of design when it came to weapons in the game espeically when designing small craft. But when it came to larger and larger ships I found it crazy. So that's why I like a small ship universe in Traveller. I just couldn't wrap my brain around a ship having 1,000s of weapon systems...

 

[Mithras]

The example of the 50 turret liner and 50 turret battleship was just theoretical. Although there is no rule as such I like to assume that civilian ships are limited to single turrets, paramilitary (scout etc) and mail ships have licences for double turrets; only military ships get access to triple turrets.

 

[Mithras]

Well that solves size! Great Aramis!

Now armour, what is it that stops the navy filling the ship with more armour?? With aircraft weight is an obvious limit, when armour is employed it is only in certain key areas. Here we can assume that every ship enjoys TL appropriate hull strengthening. Could there be some other limiting factor, like that applicable to planes?

Ship size is VERY straightforward...

Since drives are limited in SIZE by TL, the biggest ship buildable is also limited by what can be driven by the biggest drive.

Remember: TL 9 is drives A-D only... WHich means an 800 Td limit...TL 15 is drives A-Z, and a Z drive can drive a 5000Td hull.

As for why the drive size limits, if we presume that Jump and Maneuver drives both have some size-limited-by-production-tech component that has to be a singular unit rather than multiple smaller ones... call it a gravity mirror or some such technobabble... and the limit on that item is the limit on drive sizes.

I'm minded of the Necklin Rods in the Vorkosiverse. Always a pair, always a single piece each.

 

[McPerth]

Now armour, what is it that stops the navy filling the ship with more armour?? With aircraft weight is an obvious limit, when armour is employed it is only in certain key areas. Here we can assume that every ship enjoys TL appropriate hull strengthening. Could there be some other limiting factor, like that applicable to planes?

Here goes an idea about armor (feel free to take it as just garbage if you think so):

a) Maximum armor: (TL-8)/2

b) Armor volume: half as HG divided by (sqr(displacement/100))/2 (*)

c) Effect of armor on combat: substracted from the to hit roll (of course, it doesn't mean your ship is hit less often, just some hits are ineffective, on line (IMHO) with the effect armor has on personal combat).

d) Efect of armor to maneuver: every 10% of the ship spent on armor reduces your maneuver by 1

(*) so, divisor for a 100 dton ship whould be (sqr(100/100))/2, or 0.5 (so you need double volume to armor a 100 dton ship, or what is said in HG). For a 5000 dton ship, divisor is (sqr(5000/100))/2, so more or less 3.5. For a 10 dton fighter, multiplier is (sqr(10/100))/2, or aprox 0.16, so it costs 6 times more to armor such a fighter (along with point d, I guess this will stop those heavily armored fighters). If you want to penalize even more the small ships, dont halve HG formula as point b says. Of course, this formula don't work in HG, where ships may be too large.



IMHO, those rules, aside from allowing armor in Bk2 without too much complexity, also account for the increased efficiency of armor on larger ships.

 

[robject]

Well that solves size! Great Aramis!

Now armour, what is it that stops the navy filling the ship with more armour?? With aircraft weight is an obvious limit, when armour is employed it is only in certain key areas. Here we can assume that every ship enjoys TL appropriate hull strengthening. Could there be some other limiting factor, like that applicable to planes?

High Guard 1 (the 1979 version) only allowed two kinds of armor: all or nothing. If you want armor, then by golly you got the maximum for that hull volume.

 

[Mithras]

My homebrew Book 2 armour fix is similar, no points, just armour or no armour, similar to streamlining. But, I'm keener to look at rationalizing a no armour Book 2 universe....

 

[Dominator]

I think the 50-turret question is simply answered by the fact that ship category names are arbitrary: A "liner" with maximum turrets is a warship. As previously noted, the economics will drive the level of armament. If it is profitable to run a passenger service with maximum armament, then the economics is the problem, IMHO.

 

[robject]

My homebrew Book 2 armour fix is similar, no points, just armour or no armour, similar to streamlining. But, I'm keener to look at rationalizing a no armour Book 2 universe....

In that case, perhaps extend the Damage Track philosophy a bit further. After all, it is for all intents and purposes a measure of hardening of equipment versus damage.

 

[aramis]

I think the 50-turret question is simply answered by the fact that ship category names are arbitrary: A "liner" with maximum turrets is a warship. As previously noted, the economics will drive the level of armament. If it is profitable to run a passenger service with maximum armament, then the economics is the problem, IMHO.

The best way to examine the difference is to look at two otherwise identical 5000Td ships - one with 50 turrets and the gunners to match, the other without; otherwise pure cargo.

5000 _500 Hull
_100 __25 Bridge
_110 _210 JDrive W=1
_500 ___0 JFuel 1J1
__41 __84 MDrive W=1
__64 _168 PPlant W=1
__10 ___0 PFuel 1 mo
___2 __18 Model 2/bis
_200 __25 50xSR for Crew CO XO 3xAd P N 6xE M 36x???
==== ==== ==========================
3973 1030 

5000 _500 Hull
_100 __25 Bridge
_110 _210 JDrive W=1
_500 ___0 JFuel 1J1
__41 __84 MDrive W=1
__64 _168 PPlant W=1
__10 ___0 PFuel 1 mo
___2 __18 Model 2/bis
___0 ___5 50xHP
__50 __50 50xTriple Turret
___0 _150 150xBeam Laser
_256 __32 64xSR for Crew CO XO 3xAd P N 6xE M 50xG
==== ==== ==========================
3867 1242

The second is clearly the warship (and a sucky warship at that) - the extra 14 crew are due to the crew minimums in Bk2 for "big ships"... Operating costs go up by 14 gunners and 1/240th of MCr212... or about Cr897,334 per month.

Now, a real 5000 Td "Warship" looks like:

5000 _500 Hull
_100 __25 Bridge
_125 _240 JDrive Z=2
1000 ___0 JFuel 1J2
__47 __96 MDrive Z=2
__73 _192 PPlant Z=2
__10 ___0 PFuel 1 mo
___9 __80 Model 7
___0 ___5 50xHP
__50 __50 50xTriple Turret
___0 _150 150xBeam Laser
_260 __32½ 65xSR for Crew CO XO 3xAd P N 7xE M 50xG
==== ==== ==========================
3326 1338½

Why the model 7? Runs hot software.

Why is this a warship and not a freighter? an extra KCr400/trip.
The cargo space is likely to be duplicate fuel (in case of damage) and a bunch of marines. And, if we take and double the fuel, and then max out the marines in single occupancy... 2116 Td of SR gives 529 marines. A super heavy company or a decent battalion. Or, freeze them at 3.5 x that rate (allowing 0.5 Td per 7 LB for gear) and get 1851 troops. A leg regiment.

A 5000Td monster isn't a good combat vessel.

Now, the 5000Td CARRIER isn't so bad...
She'll carry 166 fighters instead of those troops... You may be wondering how I get that number: Each fighter takes 10Td, and it's pilot needs a SR at 4Td, and I'm still using double fuel!

It's deucedly ugly to play out, but it is a very workable model for big nasty invasion. A mixture of 5000Td hulls - some troopships, some carriers, some transports for the armor.

 

[Mithras]

I think the 50-turret question is simply answered by the fact that ship category names are arbitrary: A "liner" with maximum turrets is a warship. As previously noted, the economics will drive the level of armament. If it is profitable to run a passenger service with maximum armament, then the economics is the problem, IMHO.

Yes, you should be calling a liner with 50 triple turrets a heavy troop-carrier ...

 

[Mithras]

Thanks for the analysis Aramis. I think the analysis shows that a massive ship as big as a super cruise liner, mounted with guns for ship to ship combat (lets call it a 'battleship' or 'battlecruiser') is not viable. But we shouldn't be dismayed or frustrated by this, it needn't be something that needs fixing. Battleships, dreadnaughts, etc. were common a hundred years ago, less common 60 years ago, and almost extinct today. A universe without them looks a bit like our naval universe, I suppose. With high capacity multi-use amphibious and helicopter carriers stepping on to the podium, but aircraft carriers retaining the crown. .

The best way to examine the difference is to look at two otherwise identical 5000Td ships - one with 50 turrets and the gunners to match, the other without; otherwise pure cargo.

 

[mike wightman]

In a LBB2 only fleet your battleships are going to be M6 - so the 2kt hull will be the one of choice. These ships will still be equipped with as many fighters as they can carry since a fighter is really just an extra turret that costs 14t and can move by itself =)

Unless you borrow bay weapons and/or spinal from High Guard the ship killer is the mass missile salvo - beam weapons really suffer badly if you are firing 10 triple sand casters as your defensive screen (check the rules for sand casters - if you have enough you needn't work about incoming laser fire).

I envision the combat will begin to resemble a scene from nBSG - missile salvos being intercepted by fighters and anti missile fire, while missile armed fighters try to score a hit while avoiding enemy fighters, incoming fire etc.

 

[Jame]

I would still like a way to extend the hull size to 20000 tons, with a way to make them M6 J6.

Oh, and 5000 tons would be the max size at tech level 10.

 

[aramis]

In a LBB2 only fleet your battleships are going to be M6 - so the 2kt hull will be the one of choice. These ships will still be equipped with as many fighters as they can carry since a fighter is really just an extra turret that costs 14t and can move by itself =)

That depends on how you define battleship. And a 5KTd ship will NEVER be M6 under Bk2.

_ Maximum Hull Size by TL and Rating under Bk2
_ TL _ Drv ___ R1 ___ R2 ___ R3 ___ R4 ___ R5 ___ R6
__ 9 _ A-D __ 800 __ 400 __ 200 __ 200 __ 100 __ 100
_ 10 _ A-H _ 1000 __ 800 __ 400 __ 400 __ 200 __ 200
_ 11 _ A-K _ 2000 _ 1000 __ 600 __ 400 __ 400 __ 200
_ 12 _ A-N _ 2000 _ 1000 __ 800 __ 600 __ 400 __ 400
_ 13 _ A-Q _ 3000 _ 1000 _ 1000 __ 600 __ 600 __ 400
_ 14 _ A-U _ 3000 _ 1000 _ 1000 __ 800 __ 600 __ 600
_ 15 _ A-Z _ 5000 _ 5000 _ 4000 _ 3000 _ 2000 _ 2000

This highlights certain issues of Bk2.
If you define a battleship as the biggest combat craft buildable for a given TL, then they vary by TL:
TL 9 800Td R1
TL10 1000Td R1
TL11-12 2000Td R1
TL13-14 3000Td R1
TL15 5000Td R2

max jump for the TL
TL 9 Mod/3 J3 200Td
TL10 Mod/4 J4 400Td
TL11 Mod/5 J5 400Td
TL12 Mod/6 J6 400Td
TL13 Mod/7 J6 400Td
TL14 Mod/7 J6 600Td
TL15 Mod/7 J6 2000Td

The biggest flaws with Bk2 become readily apparent here:
1) The TL limits on drives are not copied from the TL tables into the SSDes chapter
2) Several "Standard Designs" are improbable
3) major granularity issues.

Issue 3 is readily solved by reworking the tables to have more lines, but that alters the maximum sizes by TL...

A Battlecarrier with loads of fighters is gonna be SLOW under Bk2, and dominate not by direct combat, but by sending fighters out. Any direct combat warship will be outgunned by the fighter carriers.