Carrier design

[Raynulf]

My meandering thoughts while making the 3rd cup of coffee for this morning led me to this scenario:

When designing "Carrier" type vessels, say carrying 4 200DTon non-starships and several fighter squadrons, what kind of allowances do you have to make for boat geometry, docking & service equipment etc on the hanger displacement tonnage?

In the traveller universe we are operating in the Power plant, Jump & manuever drives and fuel usage decreases by 10% for every TL above 10 (not counting TL 18+, btw) accounting for improvements is both the steady optimisation of tech and the leaps to 'new' approaches.

This also means that two 600ton cruisers will not be evenly matched with 1 at TL12 and the other at TL15, simply due to the latter having more compact and efficient systems.

Back to the main topic though. The next thought is effectiveness: put simply, as an escort carrier what would you want to bring? My initial though was four 200Dton boats and around 80 10ton fighters (for around 1600Dtons of escorts). How effective would these be? Would less fighters and an extra boat be better or visa versa? (I am a traveller Noobie).

The next question I have is in regard to ship design. I only have the basic traveller rule book, which gives 1 hardpoint per 100Dtons of hull, yet this is somewhat inflexible. What about military vessels vs Civilian? Yes, you standard 200Dton trader may be packing 2 turrets, but an escort craft where cargo is not a major concern will be packing as many as the hull can fit & power plant supply.

Have some guidelines for warships been worked out, or is it at the perogative of the individual designers?

 

[Raynulf]

Interesting: There doesn't seem to be an "edit post" option.... oh well.

Will work out the stats tonight for the ship and guestimate the 'hanger factor' if need be.

Just an interesting idea really, I'm curious as to the effectiveness of carrier ideology vs starship ideology.

 

[Falkayn]

Originally posted by Raynulf:
When designing "Carrier" type vessels, say carrying 4 200DTon non-starships and several fighter squadrons, what kind of allowances do you have to make for boat geometry, docking & service equipment etc on the hanger displacement tonnage?
<SNIP>
Have some guidelines for warships been worked out, or is it at the perogative of the individual designers?

To answer your last question first, it mostly comes down to individual designers and/or other aspects of the TU you're playing in.

A lot of the debate for carriers centers around what sort of target are you looking to gun down? If it's capital ships then 10-ton fighters are not your best bet, you might want to look into 30 tons or more. My Geography Direction class 'Light Carrier' design is 7,000-tons and carries 16x 30-ton space superiority fighters and 8x 40-ton heavy fighters. 200-tons starts to edge into the SDB range, which is when you have tod ecide are you building a carrier, or a battle-tender? Again, these vary based on the opponents they are meant to take out (battle-tenders carry battle-riders which are supposed to stand up to capital ships).

OTOH, to take out pirates or to raid and harass enemy shipping a lighter fighter option might be a great idea, it certainly can give you a much greater system coverage than your raw tonnage would imply.

The T20 ship design sequence does include items such as maintenance shops, launch tubes, etc. But it's upt o the designer to ensure that the hangar bay has its own fresher to the guys working on the fighters don't need to go back to quarters just to take a pee.

My T20 Downloads page has a bunch of my ship designs, and a handy MS Excel 2000 spreadsheet to make them easier to build: T20 Downloads

EDIT: BTW there is an Edit Post option, it's the icon with a pen and paper above your post. Also, v. nice to see another Aussie around, welcome!

 

[Whipsnade]

Raynulf wrote:

"When designing "Carrier" type vessels, say carrying 4 200DTon non-starships and several fighter squadrons, what kind of allowances do you have to make for boat geometry, docking & service equipment etc on the hanger displacement tonnage?"


Mr. Raynulf,

Interesting questions! I'll address them from a HG2 standpoint as I do not yet know enough about T20's ship design/combat rules. T20's rules were developed from HG2's, so I think my ravings will still be useful.

First; the hoary complaint that fighters don't 'work' in Traveller fails, like all hoary complaints, upon further examination. Fighters work just fine against major combatants up to a certain tech level, ~13. After that, nuc dampers take away the fighter's best weapon, nuc missiles, and smaller power plants allow warships to carry more armor while becoming more agile. Fighters still remain worthwhile in certain roles; recon, commerce raiding, and against certain opponents; merchant shipping, PC ships, no matter what TL.

Second; most previous Traveller carrier designs use 'launch tubes'. Vessels with tubes can launch and recover 40 small craft during each HG2 20 minute combat turn. Normal docking facilities only allow one launch per 10K dTons of carrier.

Another solution has the carrier built in a dispersed configuration; think Tinkertoy or Erector Set. Those vessels can launch all carried craft in a single turn, but they also cannot have armored hulls. This leads to 'carriers'; vessels handling craft around or below 100dT, to use tubes and 'tenders'; vessels handling multi-K dT battleriders, do have dispersed hull forms.

(I snipped your intriguing comments about increased engineering efficiency. You do realize that any increase in a warship's "power per dTon" will increase gee ratings and agility and marginalize fighters faster than occurs in HG2? Do you allow agilities beyond 6? That may help bring things back into balance.)

"Back to the main topic though. The next thought is effectiveness: put simply, as an escort carrier what would you want to bring?"

Horses for courses. What job is your carrier tasked with performing? Who are her likely opponents? 10 dT fighters are suitable for slapping around Beowulfs and Maravas, or watching a world from orbit, or showing the flag in some remote planetoid belt. 50 dT fighters would be needed if the carrier need tackle any job tougher.

"My initial though was four 200Dton boats and around 80 10ton fighters (for around 1600Dtons of escorts). How effective would these be? Would less fighters and an extra boat be better or visa versa? (I am a traveller Noobie)."

What role to the 200 dT boats play? They will only carry two turrets to your 10 dT fighter's one. They will be far more armored and have better endurance, but is twenty times the hull worth only two times the weapons?

A 10 dT fighter armed with nuc missiles can be a frightening opponent for a small, damperless, merchant ship. The same fighter would be easy meat for a warship however. This is where attrition tactics come into play. You throw a brace of fighters at your opponent hoping to swamp his anti-missile defenses while at the same time planning to lose fighters each combat round to his batteries.

Many Traveller fighters are larger than 10 dT, with most centering around 50 dT. That displacement seems to be the smallest armored hull you can reliably cram 6-gees, agility-6, and a large computer into across a range of TLs. Agility* allows the fighter to avoid being hit, armor allows the fighter to shrug off some of the automatic crtical hits it will suffer, and a large computer gives it a better chance of hitting its target before being hit in return.

"The next question I have is in regard to ship design. I only have the basic traveller rule book, which gives 1 hardpoint per 100Dtons of hull, yet this is somewhat inflexible. What about military vessels vs Civilian? Yes, you standard 200Dton trader may be packing 2 turrets, but an escort craft where cargo is not a major concern will be packing as many as the hull can fit & power plant supply."

One turret per 100 dTons has been the standard since CT. That doens't mean it has to be your standard however. You are already using other house rules so why not experiment and have fun? Sadly, I can't give you any design pointers as I've always built with the one turret per 100 dT weapon density in mind. One thing to remember; increasing the weapon density of your warships will further marginalize your fighters.

"Have some guidelines for warships been worked out, or is it at the perogative of the individual designers?"

The guideline is the one turret per 100 dT with all the bay and spinal mount tonnage costs too. The perogative of the designer remains paramount, just as the perogative of the GM remains paramount. All the matters is whether you and your's are having fun. Everything else is moot.

However, the further your designs and house rules deviate from the precpets of the OTU, the less likely that others will be able to use them. Your designs will depend on the house rules you use and not the rules we all share. This doesn't mean that you shouldn't go ahead with your plans, far from it. All it means is that the rest of us will have trouble using the materials you produce without also using the house rules you used to produce them.


Sincerely,
Larsen

* - Agility and gees in HG2 are strongly linked; you cannot have an agility rating higher than your gee rating. Of course, thanks to any house rules youmay be using, YMMV

 

[Raynulf]

My thoughts on hardpoints:

Firstly I visualise the 1 per 100Dtons limit stemming from the basic construction of the ships being a latticework of load bearing members with decks and hull attached, with a 'hardpoint' being a heavily reinforced region (eg junction of multible members) which can sustain the forces induced by the rapid movement of the turret.

That IMHO is fine for civilian vessels, where the primary concern is cost, rather than firepower. For military grade vessels however, where combat performance is paramount this limit can be adjusted to 1 hardpoint per 100Dtons for 0.1MCr each, every hardpoint thereafter uses .5 Dtons and 1MCR to add sufficient structural members. The maximum number of hardpoints any starship can have is 2 per 100Dtons as complications with the jump systems begin to occur. Non-starships are less limited due to the lack of J drives, and may be fitted with up to 5 hardpoints per 100Dtons.

I was working on this for the carrier concept.

Also, along this lines the 10Dton fighters at high TL come with smaller drives, lower fuel and requirements. For these I visualised using the 'spare volume' and the recovered space to outfit the craft more powerful engines to allow for an increase in armour and weaponry, ie: allow TL14-15 10Dton fighters to be equipped with double lasers/ missile racks.

Using the same principal, a 20Dton 2 man fighter can be converted to a 1-man heavy fighter, packing a sizable arsenal with reasonable armour into a small, agile vessel.

The carrier concept I played with last night was a TL15 4000Dton hull with 60 hardpoints. Now, since CT limits ships to 5000Dtons and drives to type Z, I 'invented' types AA, AB etc to allow for a J6.

The vessels attached were as follows: 50 10Dton fighters, 10 20Dtons fighter, 2 100Dton Riders and 1 200Dton Rider.

The riders all are fitted with max turrets (10 & 5) with 6G acceleration and heavily armoured, the 200Dton vessel also carrying 14 ships troops and a G-Carrier.

I saw this vessel as performing in 2 roles:

A) As a support vessel for a large fleet, deploying battle riders as powerful escorts for destroyers and fighters to raid observation posts and strategic targets and as recon units.

B) As part of a small task force to relatively undefended systems, where 'coverage' of the system is a larger priority than firepower, since the fleet with primarilly be blockading and raiding small, low armament vessels.

The carrier itself carries a large weapons compliment and strong armour, with it's attached vessels working in cooperation rather than on their own.

 

[Raynulf]

Hmm... probably should post some justification for this: Fuel usage and engine size reduction with increasing TL.

The basic fuel used in starships from TL10 to TL15 is hydrogen, where it is fused into helium, the resulting energy released from the fusion reaction is harnessed to power the ship, jump and maneuver drives.

That said the proportion of energy gathered from energy produced is NEVER 100%. Simply not practically possible, however, there is an expected increase in the proportion of harvested energy as the technology advances. Next, there is the 'operating energy' ie the energy input required by the powerplant to generate the fusion reaction in a stable manner and harvest the results, this decreases as TL increases as subsystems improve and new techniques of achieving the same result are developed. All up, a higher TL power plant will use less fuel to produce the same amount of energy, even though the actual reaction is the same.

Next: The reaction itself.
Low TL engines will fuse hydrogen to helium. As the TL increases does this change? Helium itself can be used as a fuel, it is harder to 'ignite' but possible. This would result in a great boost in effective fuel efficiency even if the engine technology itself hit the physical limit on hydrogen fusion efficiency.

Lastly: Usage
Does jumping ALWAYS require a set amount of energy? Or is it like maneuver drives, where different approaches and more effecient systems can produce a drive which is more efficient overall. Worth considering.

Overall these three factors IMHO more than justify an increase in fuel efficiency for high TL ships. In gameplay terms this has simply been attributed to a 10% reduction in fuel usage for TL level above 10.

The reduction in engine size (M, PP & J) that we included was based more on observation that in general, things tend to get smaller over time and I'm getting sick of typing, so I'll stop now.

 

[DaveShayne]

Originally posted by Raynulf:
Interesting: There doesn't seem to be an "edit post" option.... oh well.

The sheet of paper with the pencil is the "edit/delete post" button.

 

[DaveShayne]

Originally posted by Raynulf:
Have some guidelines for warships been worked out, or is it at the perogative of the individual designers?

Going by standard CT rules (as apparently you aren't) subordinate craft take up only as much space as they themselves displace using the Book 2 design sequence. Using Book 5: High Guard small craft (under 100 tons) are carried at their own volume by ships under 1000 tons or take up 130% of their volume on larger ships. Large craft (100 tons plus) require 110% of their volume to be allocated by the carrying craft.

The 1 turret per 100 tons is the rule even for warships using CT. The design sequences in TNE and T4 both allow you to go beyond that but those are much more detailed rulesets then the CT sequences.

 

[Raynulf]

I must admit, I am not a heiroglyphics man: I use menus and command lines. Perfect way to hide a function = give it an icon with no text near it.

Regarding ship design rules:
IMO the CT rules are designed to allow quick and easy generation of ships that are ultimately balanced as they all follow the same guidelines.

Which is all well and good, but I don't think they can really be applied as law, since the thought behind them doesn't differentiate a TL10 Freighter from a TL15 High performance war cruiser except what you choose to put in it. For that matter, for the most part a TL10 Battleship vs a TL15 in CT are fairly evenly matched in everything bar the computers aspect. Tonnage, agility, armour & weaponry are identical.

As is, I would apply the same 'modification' rules (ie TL affecting engines & fuel, and extra hardpoints) to all ship construction. IMHO as long as you keep your universe consistant it balances out.

 

[DaveShayne]

Originally posted by Raynulf:
for the most part a TL10 Battleship vs a TL15 in CT are fairly evenly matched in everything bar the computers aspect. Tonnage, agility, armour & weaponry are identical.

Say what?

Using HG a TL 10 BB will be more expensive with less armor and agility and less effective weapons than it's TL 15 successor. This is a direct consequence of TL progression for both power plants and armor. If computer size didn't cap the size of ships at lower TLs the Tech A ships would probably be larger as well.

 

[shield]

Using HG2 rules and hence almost the T20 rules, there is a massive difference between a TL15 battleship and a TL10 battleship.

Weapons are more effective, and more weapon types are available and in smaller mounts. Screens are available at TL12, especially the nuclear damper.

A TL15 light battleship (100-200ktns) will have an armour rating of about 10, 5-6G, J3-4.

A TL 10 ship will only be able to manage about 1-2G, j1, with an armour factor of about 5-6.

The main dominating factors are power plant efficiency and armour volume.

PP6, necessary for your 6G drives takes 6% of a ship at TL15, but 18% at TL10. Factor 10 armour takes 11% at TL15 but 33% (from memory) at TL10.

Normally a battleship will have about 30% of its displacement available for armour / power plant / PP fuel (rough guide from experience). At TL15 you can get PP10 + fuel and armour 10 in that space, with enough power for 6G and lots of screens and weapons. At TL10, well you can do the math.

Cheers
Richard

 

[Whipsnade]

Raynulf wrote:

"Regarding ship design rules: IMO the CT rules are designed to allow quick and easy generation of ships that are ultimately balanced as they all follow the same guidelines."


Mr. Raynulf,

That's a fair complaint. The rules are fairly generic and one could wish for more details or chrometo slather on warships. Check out either version of FF&S for all the chrome you'll ever need.

"Which is all well and good, but I don't think they can really be applied as law, since the thought behind them doesn't differentiate a TL10 Freighter from a TL15 High performance war cruiser except what you choose to put in it."

I don't follow that... Form does follow function and a freighter will look/act/operate very differently than a cruiser. The bits you add to a given 10K dTon hull will be the reason the hull will be a frieghter or a cruiser.

"For that matter, for the most part a TL10 Battleship vs a TL15 in CT are fairly evenly matched in everything bar the computers aspect. Tonnage, agility, armour & weaponry are identical."

Now you've really lost me. Which CT ship buiilding rules are you using, LBB:2 or HG2? LBB:2 is rather 'sparse' when it comes to chrome and bits, but HG2 provides more than enough to make a TL10 BB extremely different from a TL15 BB. Why do you think they are the same?

"IMHO, as long as you keep your universe consistant it balances out."

Yes, I completely agree with you there. It's your Traveller universe, apply all changes evenly, explore all consequences, and have fun!


Sincerely,
Larsen