Modular Ship Design... a crazy idea that just might work.

[blue emu (OP)]

I've been playing around with the "Modular Ship Design" idea, with emphasis on trying to come up with a practical after-burner to boost our mission ship speeds.

A 120-ton Afterburner Fighter can tow a 41,000-ton mission ship (!) and boost its speed by about 69 kps. Not particularly impressive... if you ignore the fact that it's towing a load more than 340 times more massive than itself. The Tractor Beam needs to be mounted on the mission ship, though. No room for it on the Fighter.

A 350-ton Afterburner FAC can tow that same 41,000-ton mission ship and boost its speed by over 220 kps. Now we're getting somewhere! The Tractor Beam still needs to be mounted on the mission ship, though.

A 900-ton Afterburner FAC equipped with its own Tractor Beam can tow a 16,000-ton Cruiser and boost its speed by more than 400 kps. Now this idea is really starting to look practical! The Cruiser can even have a landing bay to carry the Afterburner FAC, when it's not in use.

Designs available on request.

EDIT: Latest test results:

One of these:

Afterburner FAC II class Module    1000 tons     65 Crew     246.4 BP      TCS 20  TH 115  EM 0
11500 km/s     Armour 3-8     Shields 0-0     Sensors 1/1/0/0     Damage Control 1     PPV 0
Annual Failure Rate: 0%    IFR: 0%    Maintenance Capacity 38 MSP
Tractor Beam     

GB Internal Confinement Fusion Drive E65 2017 (1)    Power 230    Fuel Use 650%    Armour 0    Exp 36%
Fuel Capacity 85,000 Litres    Range 23.5 billion km   (23 days at full power)

This design is classed as a military vessel for maintenance purposes

... can tow one of these:

Box Launcher class Module    1150 tons     16 Crew     196.3 BP      TCS 23  TH 0  EM 0
1 km/s     Armour 3-9     Shields 0-0     Sensors 1/1/0/0     Damage Control 1     PPV 18
Annual Failure Rate: 0%    IFR: 0%    Maintenance Capacity 11 MSP
Magazine 120   


Size 6 Box Launcher (20)    Missile Size 6    Hangar Reload 45 minutes    MF Reload 7.5 hours
Missile Fire Control FC117-R100 (1)     Range 117.6m km    Resolution 100

This design is classed as a military vessel for maintenance purposes

... at 5,175 kps. Looks like a reasonable plan for colony defense... keep a bunch of Box Launcher modules in a hangar, and the Afterburner FAC tows one out to firing range, fires it off, tows it back and trades it for a full one. The empty Box Launcher modules re-load while the next attack mission is taking place.

[jseah]

Too bad we can't turn off engines on ships that are being towed. 

Then a commercial tug could be used to tow combat ships around (with engines off) on patrol to save fuel.  Then when crisis approaches, the combat ships drop the commercial engines and start their own for the combat.  Commercial engines without payload go v.fast and simply escape. 

[blue emu (OP)]

Commercial engines plus a hangar big enough to carry the military ship? Engines are always off inside a hangar.

Admittedly, it's not a perfect solution... an empty hangar weighs just as much as a full one, for instance.

[Vynadan]

I've just tried to compare boosters with and without their own tractor beam. The only difference between both designs were the tractor beam and some crew quarters I had to add to the larger version. The 300 ton FAC brought a 20kt cruiser from ~4600 to 6410, while the 800 ton FAC only reached 6380. I'm not exactly sure what the math behind the tractoring is, but I'd guess the self-tractoring booster isn't as good as the tractored one - but I base this on my observation only. Regardless, their difference wasn't that large.

On a side note, while this is all high tech with the 300 ton FAC engine flying at 1/3c (for up to 50 hours), it managed to boost a 20kt cruiser by a good 2000 km/s. I think boosters will have only marginal impact unless you tune down your mission tonnages significiantly or have upper medium level technology and higher.

[blue emu (OP)]

I'm not expecting miracles, of course... but I feel that this entire field of research could be worth investigating.

Fire-and-forget Box Launcher modules will probably have the greatest impact on short battles, while Missile Magazine modules might have a bigger impact on long battles. After-burners are just an interesting side-branch... to exploit the fact that FAC engines deliver ten times the power-to-weight ratio of normal military engines.

[Brian Neumann]

Modular design is nice for things you are not going to need much of, or for long range combat.  If you want to put heavy beam weapons on a small module you will quickly run into a problem where they don't have enough armor to survive an equivelent hit on them, and you will be in range of matching weapons while they can see you.  Missile combat does not have this problem as a small module (ie fac size) can still give you a few more weapons, or a bunch of box launchers without being particularily detectible.  I have used the idea somewhat in the past, mostly to give extra point defense coverage for a fleet.  A single 25 hull space module has enough room for 1 tractor, 4 size 1 launchers, 1 fire control (usually size 2 for some range) and about 4 hull spaces magazine which translates to around 60-70 missiles.  By the time any missile attack is able to hit them, they have already fired off all of thier ammo.  Thier biggest drawback is when jumping into a hostile system they take one or your ship slots.  The result is you either leave them behind to get the most concentrated firepower, or you need a lot more jump engines. 

Putting the jump engine on the module doesn't work all that well because you need the module to be the same size as the ships it is taking through the jump.  Sensors modules look good, but I like to have really big passives (40-50 hull spaces or around 2,000-2,500 tons).  This is a pretty big module and is going to have a large effect on the towing ships speed.  For smaller passive sensors this would be a good way to get a size 6-8 passive for your small combat ships.

Where I found modules to be really helpfull was with resuply of front line combat ships.  A commercial ship with lots of maintenance and a tractor beam could tow a fairly big module (50+ hull spaces) of magazines or fuel without being slowed down much at all.  The module could then be dropped off near the front while the freighter emptied its engineering spaces into all the ships that had used theirs up and then it would go home to pick up more supplies.  Meanwhile the combat related module could stay put and be available for the combat ships to resuply from.

Brian

[blue emu (OP)]

Just had another brainstorm... an idea that is certainly worth testing:

What happens when one of the linked ship modules has Hyperdrive, and the other doesn't? Is it worth carrying a Tractor Beam equipped Hyperdrive-FAC in a Boat Bay inside your mission ship, to tow you around when you are outside the Hyper-limit?

FAC engines are 10x power, and Hyperdrive is 10x speed. That's a 100x multiplier over the usual towing boost... assuming that a Hyperdrive tow is even possible.

EDIT: 2x power (not 10x  ), 10x Speed = 20x in total

It seems to me that if this works at all, it should work very well indeed.

[Girlinhat]

Oh wow that would be amazing.  A size 20 FAC with a hyper engine, a tractor, and some marginal fuel.  Small enough to fit in a single hangar and potentially provide, what... 20 engine's worth of thrust to your regular ship?  FAC gets 2x speed, hyperdrive boosts that up to 20x.  20 engines for 21 hull space of hangar could be well worth it if you can even pretend to get the enemy outside of hyper limit.  A sensor platform or maybe a single transponder ship could be used to lure enemy ships outside of hyper, where your ships suddenly get a huge speed boost and tear circles around the enemy.

[blue emu (OP)]

I'm positive that this whole field of design philosophy is just loaded with clever new possibilities... we just need to think of them.

I'm teching up my Hyperdrive tech now, to get it compact enough to fit in a FAC. I'll be able to test it out in a few more game-years.

[blue emu (OP)]

It works!



That's a 1000-ton Hyperdrive FAC towing a 16,000-ton Heavy Cruiser at 55,470 kps!

You have to be really careful about just how you issue the orders, though, because you cannot issue "Enter Hyperdrive" orders to a fleet that contains non-Hyperdrive ships. That option doesn't appear on the orders menu. You need to first move the task group into position outside the Hyperlimit, then detach the Hyper-FAC into a seperate task group, then give it a series of queued orders: "Tractor specified ship", "Enter Hyperdrive", and "Move to..."

It does, however, work very well. Fifteen hours to Pluto.

Impressed yet? 

[Girlinhat]

I'm thoroughly impressed.  This might be a viable way to deliver certain ships to binary systems.

Also, what if you uncheck the little "intelligent order list" thing?  There's an option that lets you display all the normally invalid commands that may allow you to hyperdrive.

[blue emu (OP)]

I'm thoroughly impressed.  This might be a viable way to deliver certain ships to binary systems.

Also, what if you uncheck the little "intelligent order list" thing?  There's an option that lets you display all the normally invalid commands that may allow you to hyperdrive.

Didn't try that, but yes... it might work. I was trying to get the job done without any "fudging".

It should be pretty easy for you to replicate my test. I'm only up to Hyperdrive size x1.6, and that's already compact enough to build a Hyper-FAC with nothing but one Hyper-FAC engine, a tractor beam, and minimal crew accomodations and fuel. As my Hyper tech improves, I can increase the fuel load... although at five hours per billion km, it really doesn't need more than a few days endurance.

[UnLimiTeD]

I dunno, I'd just put hyper engines on the destroyer.^^
Though, will the destroyer be able to fight while the FAC tows it around?
That would open whole new way of missile evasion.^^
As for the box launcher concept, get a few launchers of so you get to 1000 Tons without the bridge.
Thats 50 Tons of bridge after all.
A lot of space in the long run.
Nonetheless, for the same space you'd be able to get 8 fighters of 250 tons, probably still faster and all with a bunch of boxes, you'd need to do a test on what actually delivers more punch.
And wether it wouldn't be more useful to just use reduced size launchers with long ranged missiles.

[Brian Neumann]

In the past when I did the modular idea for offensive missile combat I ended up deciding that the 25% size launchers were a better idea than the box launchers.  This is mostly because box launchers require either a planet with maintenance facilities, or a big enough hanger deck to reload the launchers.  The 25% size launchers could however be reloaded in the field.  Granted that you get about 60% more launchers when you go to the box style, if you need to shoot them again you can only do that after a going into a carrier, or being towed back home.  With the carrier idea it works, but if you are doing this right you probably don't have many carriers with hanger bays available, while you do have a bunch of modules.  This makes for a really long long reload time.  The 25% size launchers however can have a small magazine with 1 reload internal and then your fleet just keeps sailing along while they reload.  The reload times are probably fairly close in scale also.  A launcher sized matched by the reload size takes 50 minutes to reload.  A box launcher of size 6 takes 45 minutes while a size 4 box launcher takes 30 minutes.  All of these are out of combat times, but lots shorter than most movements are going to be.  Up to you what you want based on your overall strategy, this was just what worked for me.

Brian

[Vynadan]

I dunno, I'd just put hyper engines on the destroyer.^^

If you just want to hyper it, outsourcing this to a booster would always be profitable. This way you only have one engine with 1.6 times its size and cost, whereas a full sized warship would receive this penalty on its many engines. Even if you tech it down to 1.0x the size, it still doubles in cost for each engine.

I'd make it dependant on how hyper drives are technobabbled - I wouldn't be comfortable with exploiting this if all ships needed to be hyper capable to do this. However, this gives a good reason to actually put the tractor beam on the booster and not the mission module.