Launch Tubes

[robject]

Traveller allows a range of missile sizes, with missile launchers geared to those specific sizes. Larger ships, presumably, can launch more devastating missiles of various types.

The larger missiles are essentially the sizes of small craft, and even small starships. Some are deadfall ordnance, but others are more traditionally built missiles: a damaging payload with an engine attached.

At the small craft and larger size, a missile can be propelled by an M-drive.

Which leads me to the next question: why not have a launcher of actual fighters?

In other words, these large missile launchers also handily represent launch tubes.

* * *

I think launch tubes are interesting. They allow the rapid(?) delivery of things, effectively creating a short-ranged deployment zone around your large ship.

I also think that having launch tubes as part of ship design "for free" is a good thing.

What are your thoughts on the matter?

 

[Spinward Flow]

Launch Tubes require 25 times the tonnage of anything launched from them (LBB5.80, p32).

Imagine using Launch Tubes as a "poor man's spinal weapon" for planetary bombardments using ... planetoids ... from orbit against surface targets. o:

And for anyone who isn't quite sure what that would look like, well ... here's a video reference for you to review. (58 second youtube link)



At TL=8-10 the only spinal mounts available (in LBB5.80) are Particle Accelerators (A, B, C and J), all weighing in around 5000 tons for the weapon itself plus an additional 500 or 800 EP to energize the weapon. Crew requirements for these spinal mounts are 45-55 gunnery crew. Power Plants to power the weapons would be either 2000 tons (TL=8) or 1500 tons (TL=9) or even 1500 for the C or 2400 tons for the J particle accelerator spinal mounts (TL=10), requiring an additional 15-24 engineering crew for the power plant needed to energize the weapon.

So in an extreme, pre-meson gun era ... let's take the TL=10 particle accelerator J spinal mount as the context comparison.
Weapon tonnage: 5000 (800 EP)
Power Plant tonnage supporting weapon: 2400 (800 EP @ TL=10)
Fuel tankage required for power plant: 800 tons (1 ton per EP)
Crew: 50 gunnery (5 officers, 15 petty officers, 30 ratings), 24 engineering (2 officers, 5 petty officers, 17 ratings) = 7 single occupancy staterooms, 67 single occupancy cabins = 162 tons
TOTAL Tonnage: 5000+2400+800+162 = 8362 tons
MCr: 3000 (weapon), 7200 (power plant), 81 (crew accommodations) = 10,281

Luanch Tubes are 25 times the tonnage of the maximum size that can be launched from them (LBB5.80, p32) and requires a crew (LBB5.80, p33) of 10 consisting of 1 officer and a preponderance of petty officers. So using the above 8362 tons as our benchmark available tonnage to play with ... how "big" of a launch tube can you fit into the same amount of starship tonnage?
Crew: 10 flight (1 officer, 5 petty officers, 4 ratings) = 1 single occupancy stateroom, 9 single occupancy cabins = 22 tons
200 ton Launch Tube * 25 = 5000 tons
3300 ton hangar bay (capacity for 15x 200 ton craft)
TOTAL Tonnage: 5000+3300+22= 8322 tons
MCr: 10 (launch tube), 11 (crew accommodations) = 21 o:

So for almost the exact same tonnage (8322 vs 8362, a reduction of 40 tons) and 0.204% of the cost o: in construction ... you can equip a TL=10 ship with a o: MASS DRIVER o: that can "hurl rocks" (or even wreckage!) up to 200 tons in size gathered from an asteroid/planetoid belt in a system (up to 15 planetoids of up 200 tons each!) and launched at a planetary surface to bombard it from orbit. A launch tube can launch up to 40 vessels in one combat turn (LBB5.80, p38), meaning the launch tube can "fire all" of the contents of the hangar bay holding planetoids within 20 minutes (one per 30 seconds!) given enough planetoid bodies to launch.



I am reminded of a certain episode historically broadcast on Terra all the way back on 6 Mar 1988 which included the following inspirational line at 3m29s for how this bit of starship design took the form it has in responding to this thread.

"You don't suppose there's any way Dread could stop it, hm?"
"200 tons of smokin' metal ..."

Sometimes, the best way to defeat a high tech defensive system is with a really really REALLY low tech system that isn't often used as a weapon.

Sure, a deeply buried meson gun planetary defense weapon can be extremely hard to destroy from orbit with "conventional weapons" (as if there's anything "conventional" about meson guns!) ... but what about if you bombard the planetary surface with LOTS OF ROCKS that send MASSIVE seismic shocks underground from orbit to "batter" the deeply buried meson gun in a way that disables it using the echoes of the impact shocks on the surface? Sure, the meson gun could fire at individual incoming rocks to destroy them ... one by one ... which is great when there's ONLY ONE ROCK being thrown at you. But when there are dozens of rocks? Hundreds of them?

As an attacker, all you need to do is essentially SATURATE the surface with more rocks than the meson gun can fire at and destroy before impact ... and given the slow rate of fire for spinal weapons (one shot every 20 minutes, per LLB5.80), using an extremely large 200 ton capacity Launch Tube that can shoot "a lot of rocks" at the surface above a deeply buried meson gun thanks to a faster launch rate than the meson gun's rate of fire ... well ... it's just a question of bringing enough big rocks to get the job done, wouldn't you say?

"Throw rocks at them."

Even in space, sometimes the best weapon is an exquisitely well aimed rock.

 

[mike wightman]

Launch tubes have been a thing since 79 HG 1e - see the AHL for their incorporation.

 

[robject]

Thank you, Spinward, for showing how to throw mass with Book 5.

Here's how it is in Traveller5.


First are appropriately called "Slug Throwers". These are starship-grade, glorified machine guns, firing slugs about 75mm in size. They can be penetrators, explosive, or even sensors. These can be turret sized or greater.


Next is the "Salvo Rack". Its payload is larger, maybe 10cm "missiles". Salvo racks are bay weapons (or better).


Third is Ortillery proper. Deadfall is unpowered, and ranges from backpack-sized to small-craft-sized ordnance. This is the mass driver. Ortillery is a bay weapon (or better).


Fourth is the Rail Gun. These are remotely-sited weapons, operating from a distant moon or planetoid in the system. The rail gun is for attacking surface or orbital targets, and launches missiles ranging from the standard "Traveller" size through small-craft-sized missiles.

Typically, the Rail Gun mines the thing it's installed on, builds slabs or billets, adds guidance systems and enhancements, then launches them to their destination.

The Rail Gun is a bay weapon (or better)


Fifth is the Missile launcher proper. They're designed to launch smaller missiles -- backpack-sized up to the typical "Traveller" sized missile.


Then comes the Kinetic-Kill missile bay. These beasts are designed to launch powered missiles that are smallcraft sized or larger.

This is the candidate for launching fighters and small riders. It would explain one use for the missile-form smallcraft (they look like bullets, don't they?)

KK Missile launchers, as noted, are bay weapons (or better).


Finally is the antimatter missile launcher. This is a launcher designed with the extreme safety measures to handle and delivery antimatter missiles. It's a TL 20 technology. You can fit one in a barbette.

 

[whulorigan]

Here's how it is in Traveller5.


First are appropriately called "Slug Throwers". These are starship-grade, glorified machine guns, firing slugs about 75mm in size. They can be penetrators, explosive, or even sensors. These can be turret sized or greater.

I typically imagine them as a type of Gauss Gun, rather than CPR.

 

[Condottiere]

It's one to ten in Mongoose Second, but at least you know that the passengers and crew will survive.

For most normal, uncatapulted, launches, it's about one to one plus to two.

Can mass drivers launch smallcraft? I think the jury is still out on that, though they can slow throw rocks for industrial processing and postal service.

Missiles, canisters and torpedoes may get some form of a push, before they light up; with railguns and mass drivers, propulsion is inherent.

Which leaves us with machine guns and cannons.

I have heard of explosive propelled catapults, and I think internal combustion.

 

[bookwyrm]

when I think of Launch Tubes, I think of Battlestar Galactica, both the Basestars and Battlestars.

'The Moon Is A Harsh Mistress' (1966) by Robert A. Heinlein, has a nice little battle, where the Lunar Penal Colony used large rocks launched by rail launchers to get Earth to pay attention to their requests. really makes you think twice about standing under anything moving fast from orbital plus distances.

of course Earth has a bunch of ships with weapons and marines that can be sent to deal with this problem...

ordinance for a rail launch system would also be cheap, just get a bunch of rocks of the right size, or make them the right size, point in the right direction, and launch! and with a ship being mobile and able to fire outside the range of planetary defense systems...

 

[Spinward Flow]

when I think of Launch Tubes, I think of Battlestar Galactica, both the Basestars and Battlestars.

Vipers!

'The Moon Is A Harsh Mistress' (1966) by Robert A. Heinlein, has a nice little battle, where the Lunar Penal Colony used large rocks launched by rail launchers to get Earth to pay attention to their requests. really makes you think twice about standing under anything moving fast from orbital plus distances.

Already ahead of you.

"Throw rocks at them."

Even in space, sometimes the best weapon is an exquisitely well aimed rock.

 

[whartung]

when I think of Launch Tubes, I think of Battlestar Galactica, both the Basestars and Battlestars.

True, but as documented in Book 5, and exemplified by AHL, a launch tube is like a rifle with a magazine of fighters, allowing fast delpoyment of them.

In BSG we never see fighters line up to be pressed in to a tube. It's more rendered as something similar to an aircraft carriers catapult.

Now, obviously an aircraft carrier is designed to deploy large quantities of aircraft quickly, but in truth the catapult is there simply to boost initial lift for the airplane, its not there to make deployment faster.

The launch tube can launch a ship every 30s.

Apparently a modern aircraft carrier can match that rate, using all 4 catapults.

 

[mike wightman]

Why not use gravitic acceleration in the launch tubes?

BSG has multiple arrays of launch tubes but the effect is the same as in HG - you can launch all your fighters in a turn.

 

[Condottiere]

Reactionary rockets might damage the tube.

Gravitic thrust might need some form of physical guidance.

Though considering that would be required from normal launch facilities from full or partial hangars, doesn't seem damaging.

 

[Spinward Flow]

you can launch all your fighters in a turn.

Well, so long as you only have 40 of them (or less) ...

 

[mike wightman]

Obviously, you can always install additional launch tubes if you have more than 40. That's why the AHL has two launch tubes.

 

[Condottiere]

There's a point of diminishing returns.

In Traveller, spacecraft performance is divided on volume, occupied or not.

 

[bookwyrm]

wow! T20 doesn't say any thing about them being rapid launch systems. oops, just looked, and it does say they are a rapid launch system, just not how fast. now that I think about it, I guess there would be a difference between a launch catapult system and landing/hanger bay. just hadn't really thought about it much, as I mostly think of smaller ship designs.

I've been learning so much lately about ship building. both commercial & military.

 

[Spinward Flow]

I've been learning so much lately about ship building. both commercial & military.

 

[Condottiere]

 

[infojunky]

Launch Tubes, then ok, like torpedo tubes. Like On subs? Capable of ejecting anything that fits the bore. I can go with that.

I really liked how they where handled in Leviathan and the IISS Ship Files.
The bigger the “tube” to what it can launch should control its rate of fire.

Then the question could a launch tube launch sand as well as missiles and the like.

Does it require a hard point?

 

[Condottiere]

Lots of ship systems should require hardpoints.

 

[mike wightman]

If you take a gander at the early ship plans you will often find missile launch tubes rather than a turret mounted missile rack.