Necessity of Launch Tubes

[Condottiere]

Spaceships: Launch Facilities

1. The VTOL angle seems to be covered by helicopters, which in our case would likely be a launch or recovery from an ordinary launch facility.

2. Short take-off implies that the smallcraft left unassisted but at speed from the flight deck; thus making the catapult function of the launch tube unnecessary.

3. The other end of the acronym would imply that recovery was done at near matching velocity to the carrier, so that touchdown in the recovery bay (presumably) doesn't resemble Vipers skidding along in the Galactica.

4. The carrier will support joint combat aircraft carrying out up to 420 sorties over five days and be able to conduct day and night time operations. The maximum sortie rate is 110 joint combat aircraft sorties in a 24-hour period. The standard airgroup of 40 aircraft includes the Lockheed Martin F-35B joint strike fighter, the EH101 Merlin helicopter and the maritime surveillance and control aircraft (MASC). The maximum launch rate is 24 aircraft in 15 minutes and the maximum recovery rate is 24 aircraft in 24 minutes. So if the stars align, the QE could launch a fighter every 37.5 seconds, or let's say nine fighters per six minute round. Not accounting for the fact the involvement of moving from a pressurised to a non-pressurized environment.

 

[CosmicGamer]

Hmm, just had a thought.

Instead of a tube, a launch turret.

 

[Reynard]

Still need 25x the largest vehicle displacement. What is the function of the turret, directional launching?

 

[Condottiere]

It would be like launching a seaplane, so some form of short catapult.

Though with a docking clamp, doesn't seem necessary.

 

[Reynard]

Remember a docking clamp doesn't mention any fuel or crew transfer ability. Docking arm has fuel and air transfer but isn't meant to hold a ship during transit. Can you imagine how long it must take to get a crew EVAing out to their craft for launch compared to a regular docking bay or hangar?

 

[CosmicGamer]

What is the function of the turret, directional launching?

Yes. My thought of a turret launcher was for use with the concept of a launcher providing a high degree of initial push off and doing so in a desired direction without having to change the facing of the carrier would be advantageous.

 

[AndrewW]

Remember a docking clamp doesn't mention any fuel or crew transfer ability. Docking arm has fuel and air transfer but isn't meant to hold a ship during transit. Can you imagine how long it must take to get a crew EVAing out to their craft for launch compared to a regular docking bay or hangar?

Docking clamps do allow for crew transfer.

The docking clamp allows access between the two vessels.

 

[phavoc]

Maybe we can all get together and crowdsource a better concept for the launch tube?

In my mind if you are going to pay for all that space it needs to provide a positive aspect, like launching ships at 10-12g's. But that begets the question, how do you reasonably balance it being an accelerator to keep the launch rates within reason? Obviously there needs to be a launching mechanism of sorts, like how the Arrival Vengeance does it, keeping the fighters on a track like structure and dropping them into the tube like bullets.

I don't think recovery should be by launch tube though, that should be done via some sort or recovery bay. But that also increases tonnage by duplicating facilities.

Anybody interested in starting a crowdsourcing thread?

 

[Condottiere]

What you may want is High Guard, Second Edition.

As regards the turret concept, maybe a turntable on a hardpoint, with a mini catapult.

 

[Annatar Giftbringer]

Perhaps a silly idea, but how about splitting the launch tube tonnage into two parts? One part becomes the actual launch tube, and the other part is designed to be a separate retrieval bay. That way one might justify being able to land several craft per turn through the tube without changing any rules.

For example, a lunch tube for 10 dTon fighters would require 250 dTons. Put a hangar in the middle, large enough to store all the needed fighters, add a... Let's say 100 dTon launch corridor in one end and a 150 ton landing space in the other end, both parts connected to the hangar.

 

[phavoc]

Perhaps a silly idea, but how about splitting the launch tube tonnage into two parts? One part becomes the actual launch tube, and the other part is designed to be a separate retrieval bay. That way one might justify being able to land several craft per turn through the tube without changing any rules.

For example, a lunch tube for 10 dTon fighters would require 250 dTons. Put a hangar in the middle, large enough to store all the needed fighters, add a... Let's say 100 dTon launch corridor in one end and a 150 ton landing space in the other end, both parts connected to the hangar.

That is a very good idea. Since the description for launch tubes says only that they are recovered and launched through the tube, that sidesteps the issue of how (not to mention how dumb it is to do that from an operations perspective).

 

[Condottiere]

Less of a tube, and more of a funnel.

 

[madmike]

Perhaps a silly idea, but how about splitting the launch tube tonnage into two parts? One part becomes the actual launch tube, and the other part is designed to be a separate retrieval bay. That way one might justify being able to land several craft per turn through the tube without changing any rules.

For example, a lunch tube for 10 dTon fighters would require 250 dTons. Put a hangar in the middle, large enough to store all the needed fighters, add a... Let's say 100 dTon launch corridor in one end and a 150 ton landing space in the other end, both parts connected to the hangar.

Annatar

I was not happy with the allocation requirement at all so included a dispersal area within 25x launch tube requirements when I wrote Anderson and Felix Guide to Naval Architecture.

"Allocation for a launch tube includes the launch tube, launch and recover machinery and the dispersal area outside the launch tube itself."

 

[Reynard]

For the last 30+ years I always assumed the 'launch tube' included launch, recovery and the mechanism to move craft quickly in and out between this and the hangar storage area. Some here are taking the tube descriptor too literally. Even official deck plans don't always show a tube configuration.

 

[F33D]

For the last 30+ years I always assumed the 'launch tube' included launch, recovery and the mechanism to move craft quickly in and out between this and the hangar storage area. Some here are taking the tube descriptor too literally. Even official deck plans don't always show a tube configuration.

If you've really played for the last "30+ years" then you remember the deck plans of the AHL and its launch tubes. YES, they are long tubes running through the ships. NO, no one is taking this "too literally". Just as presented in Traveller approved deck plans.

There ARE people trying to make excuses for stupid design rules though... :roll:

 

[Reynard]

The AHL (and I have the boxed game set with the myriad color deck maps) deck plans also show the load/retrieval layout as well as the actual tubes and storage. That was my first solid graphic example for the launch tube system. There are and have been many books detailing carrier deck plans and launch tubes. Some are suspect for staying true to the concept but many show how the tube can be configured other than the actual tube idea and still reasonably stay on target.

 

[F33D]

The AHL (and I have the boxed game set with the myriad color deck maps) deck plans also show the load/retrieval layout as well as the actual tubes and storage. That was my first solid graphic example for the launch tube system. There are and have been many books detailing carrier deck plans and launch tubes. Some are suspect for staying true to the concept but many show how the tube can be configured other than the actual tube idea and still reasonably stay on target.

In MGT they are tubes. See the design rules.

 

[Reynard]

Well then, by your strongly put admission, launch tubes in MgT must be tubes and not any of the variants put forth on this topic; no turrets or multi-hatch hangars et al. Either launch individually by form fit bays, hangar facilities and docking clamps outside the vessels all of which take 30 minutes per craft or build a tube for multi-launch. So simple.

 

[heron61]

What I'd like to see is both useful launch tubes and also carriers that don't use or need them.

So, there would be carriers that used docking clamps that could launch many or even most fighters in one turn. Given that we know from the High Guard errata that "The docking clamp allows access between the two vessels.", personnel, air, and fuel can all be transfered to the fighters, this should work fine and I'd like to see carriers designed like this. They'd use repair drones or robots for routine maintenance on the fighters and would have a couple of large hanger workshops for handling more serious repairs or problems.

At that point, launch tubes need to provide significant benefit. Maybe an additional 6G to 12G boost (on top of the fighter's normal acceleration) for their first turn. I have no idea if this would be sufficient to make up for the space lost to a launch tube, but at least it's something.

 

[F33D]

Maybe an additional 6G to 12G boost (on top of the fighter's normal acceleration) for their first turn. I have no idea if this would be sufficient to make up for the space lost to a launch tube, but at least it's something.

No. 6-12 G's for a second or two would make no real difference. Thus the tubes would just be a horrible waste of tonnage.