Low tech ships - Need help

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msprange
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Re: Low tech ships - Need help

Postby msprange » Thu Nov 16, 2017 5:05 pm

Reynard wrote:
Thu Nov 16, 2017 4:59 pm
TL 5 ships? Getting into Flash Gordon territory there. Does it look like an old flatiron?
You probably don't want to spend much time in it!
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baithammer
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Re: Low tech ships - Need help

Postby baithammer » Thu Nov 16, 2017 5:56 pm

Condottiere wrote:
Thu Nov 16, 2017 4:04 pm
Manoeuvre drive zero is ill defined; going by canon, not possible since the technology isn't invented until two technological levels later.

As compared to detachable bridges, where thrust zero is supposedly enough to make a soft planetary landing, presumably Terra.
Its designed to provide enough thrust to keep a craft in orbit and for controlled landing. With its stat block would be about 0.5 g ( Speed band number 5 in vehicles), which would be useful outside a gravity well.
A manoeuvre drive with Thrust 0 allows for station
keeping to maintain position (such as with an orbiting
station) but is not sufficient to move the hull any great
distance.
The thrust 0 m-drive is a TL7 technology.
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Re: Low tech ships - Need help

Postby DivineWrath » Fri Nov 17, 2017 12:42 am

I'm avoiding using fission as a power source for these ships. I'm declaring that radioactives are quite rare. If I did otherwise, then chemical power plants would serve no purpose. Fission is better in all ways.

Likewise, TL 7 M-0 drives aren't available as artificial gravity hasn't been invented yet by anyone in this solar system, nor has anyone been in contact with any outside civilization that might have artificial gravity.
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Re: Low tech ships - Need help

Postby baithammer » Fri Nov 17, 2017 4:14 am

Chem plants live between High Capacity Batteries and the fission plant, good for generating medium power for long periods of operation.

Another justification for chem plants would be a prohibition on radiologicals in space.
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Re: Low tech ships - Need help

Postby Reynard » Tue Nov 21, 2017 1:51 pm

A couple design attempts for TL 7 spacecraft.

100 ton TL 7 Space ship
Hull: standard, Light, Heat shield, Non-gravity hull
Armor 0
Reaction drive: 1g
Reaction fuel: 2.5tons/hour, 2 hours (surface <-> moon)
Power: Chemical (20 power); Basic ship power 20
Fuel: 2 weeks operation
Bridge: Standard
Computer: /5
Software: None
Sensors: Prototype (-6DM)
Crew/staterooms: Pilot, Engineer, Maintenance and Medic / 4 staterooms
Cargo:17
Options: Solar sail, Aerofins

If the ship wants to travel beyond the bounds of a single world, solar sails are a must once it boosts to and from the surface. The cargo space could be used for an extra stateroom or two for specialized passengers plus equipment for specific missions such as surveys. Maybe a modular design. The ship will need a fuel source at both ends of a route.

1000 to TL Long Hauler
Hull: Dispersed, Light, non-gravity
Armor: 0
Reaction drive: 1g
Reaction fuel: 25 tons/ hour, 24 hours (Near neighborhood world)
Power: Fission (200 power); Basic ship power 200
Fuel: 2 weeks operation
Bridge: Standard
Computer: /5
Software: None
Sensors: Prototype (16 DM)
Crew/Stateroom: Pilot, 2 Engineers, Maintenance, Medic/ 4 staterooms
Cargo: 319 staterooms and/or cargo

I use the information in other editions suggesting fission fuel rods last between one to ten years so refueling won't come up in a game campaign. A ship like this is good for travel to inner system worlds.
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Re: Low tech ships - Need help

Postby AnotherDilbert » Tue Nov 21, 2017 2:44 pm

Reynard wrote: Hull: standard, Light, Heat shield, Non-gravity hull
Reaction drive: 1g
Partial streamlined and only 1 G, it will have problems to take off and land.

Reynard wrote: If the ship wants to travel beyond the bounds of a single world, solar sails are a must once it boosts to and from the surface.
You mean Solar Panel?

A Solar Sail is an (extremely slow) propulsion system that is hardly worth having when reaction drives are available.
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Re: Low tech ships - Need help

Postby Condottiere » Tue Nov 21, 2017 2:59 pm

You could use the solar sail for orbital adjustment.
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Re: Low tech ships - Need help

Postby DivineWrath » Tue Nov 21, 2017 6:10 pm

Well, this is one of the ships I developed recently.


TL 7 Missile Frigate
1000 ton TL 7 Space ship
Hull: Close Structure, Non-gravity hull, Reinforced
Armor 7, Hull 484
M-Drive: Reaction 2, 12 unit of thrust (6 hour burn)
P-Plant: Chemical (~2 days), Solar Panels (indefinitely)
Computer: /5
Software: None
Sensors: Basic (-4DM)
Crew/staterooms: Captain, 3 Pilot, 1 Engineer, 2 Maintance, 1 Medic, 20 Gunner, 1 Administrator, 3 Officer / 32 staterooms
Cargo: 40.1
Options: Hamster Cage (for 170 tons), Medbay, Workshop
Weapons: 8 Missile Barbettes, 2 Autocannon - single turrets, Ammo storage for over 6 hour of combat
Armoured Bulkheads: Bridge, Reaction Drive, Chemical Power Plant, Solar Panels


This ship is built to be able to make the long journey from one world to another in the same solar system. For instance, Earth to Mars. The hamster cage has enough space to give artificial gravity to all state rooms, common areas, medbay, and workshop. The solar panels allow for power during a long voyage and for orbiting planets for the long term. The chemical batteries are to be used during periods the solar panels are retracted, such as combat. It is designed to destroy all opposition in a flurry of missiles. It has minimal point defense (in the form of autocannons) in case something gets through, so it is reliant on other ships for close range defense.

Tell me what you guys think.
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Re: Low tech ships - Need help

Postby Reynard » Tue Nov 21, 2017 6:54 pm

Partial streamlining still allows takeoff and landing but at a penalty at a cheaper hull cost. The aerofins reduce the penalty.

I did mean solar sails. Reaction fuel mass gets your ship nowhere especially with smaller ships. Once you leave orbit, you deploy the sail and make the journey to the destination at no real mass cost. At the destination you use the reaction drive to decelerate. The Hauler can waste a little more cargo potential for fuel and you still don't get far. TL 7 is not kind to long space travel and that's why civilizations cheer when science announces maneuver drive technology.
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Re: Low tech ships - Need help

Postby DivineWrath » Tue Nov 21, 2017 7:17 pm

Could I get stats on primitive sensors?

Anyways, here is the stats for my TL 7 weapons.

Turrets
Weapons TL Power Tonnage Cost (Mcr) Damage Range Magazine Traits
Autocannon 7 0 0 0.5 1D Short 60 Auto 4
Heavy Cannon 7 0 0 0.5 2D Short 12

Barbette
Weapons TL Power Tonnage Cost (Mcr) Damage Range Magazine Traits
Autocannon 7 0 5 3 2D Short 30 Auto 4
Heavy Cannon 7 0 5 3 3D Short 6

Small Bay
Weapons TL Power Tonnage Cost (Mcr) Damage Range Magazine Traits
Autocannon 7 5 50 8 3D Short 60 Auto 4
Heavy Cannon 7 5 50 8 5D Short 12

Medium Bay
Weapons TL Power Tonnage Cost (Mcr) Damage Range Magazine Traits
Autocannon 7 10 100 16 4D Short 84 Auto 6
Heavy Cannon 7 10 100 16 7D Short 12

Large Bay
Weapons TL Power Tonnage Cost (Mcr) Damage Range Magazine Traits
Autocannon 7 10 100 16 4D Short 84 Auto 6
Heavy Cannon 7 10 100 16 7D Short 12

Autocannon Ammunition
Weapon Number Cost (Mcr) Tons
Turret 60 0.005 0.25
Barbette 60 0.010 0.5
Small 60 0.020 1
Medium 60 0.040 2
Large 60 0.200 10

Heavy Cannon Ammunition
Weapon Number Cost (Mcr)
Turret 12 0.005 0.25
Barbette 12 0.010 0.5
Small 12 0.020 1
Medium 12 0.040 2
Large 12 0.200 10
Reynard
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Re: Low tech ships - Need help

Postby Reynard » Tue Nov 21, 2017 9:59 pm

"Could I get stats on primitive sensors?"

Extrapolation. Basic has no cost, weight or power. The progression of accuracy decreases rapidly at lower TLs. -6DM seems reasonable. Sucks to be a 1970s spaceship. Space combat would be a test of resolve or stubbornness.

It seems space combat would be more for orbital superiority to control satellites or an ortillary position.
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Re: Low tech ships - Need help

Postby AnotherDilbert » Tue Nov 21, 2017 10:25 pm

Reynard wrote: Partial streamlining still allows takeoff and landing but at a penalty at a cheaper hull cost. The aerofins reduce the penalty.
You will not get very far from a 1 G world with only 1 G thrust.

Reynard wrote: I did mean solar sails. Reaction fuel mass gets your ship nowhere especially with smaller ships.
A 100 Dt ship with a 5 Dt sail at 1 μm would be 35 km². With a trust of ~8 μN/m² it would produce, at best, a force of 280 N. If the ship masses 1000 tonnes that would be an acceleration of 280 / 1000000 ≈ 0.0003 m/s² ≈ 0.00003 G.

1 h at 1 G would produce a speed of 10 m/s² × 3600 s = 36000 m/s.
1 week at 0.00003 G would produce a speed of 0.0003 m/s² × 3600 s × 24 × 7 ≈ 180 m/s.
The solar sail wouldn't make any difference. You need months or years to get anywhere with a solar sail, with 2 weeks of PP fuel it's irrelevant.


A solar panel to extend the mission duration would get you further.
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Re: Low tech ships - Need help

Postby Reynard » Tue Nov 21, 2017 11:03 pm

A solar panel doesn't extend anything if your ship can't carry enough reaction fuel to go anywhere.
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Re: Low tech ships - Need help

Postby AnotherDilbert » Tue Nov 21, 2017 11:45 pm

You don't have to accelerate all the way, just boost an hour for a speed of 36 km/s, and then drift at constant speed to the destination and decelerate with a reciprocal boost.

36 km/s will get you to the moon in ~10000 s ≈ 3 h, or to Mars or Venus in 2 weeks at closest passage.

A solar panel would conserve PP fuel, so allow longer voyages.
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Re: Low tech ships - Need help

Postby baithammer » Wed Nov 22, 2017 12:53 am

Vehicles 2nd ed has rules for tl7 sensors.
DivineWrath wrote:
Tue Nov 21, 2017 7:17 pm
Could I get stats on primitive sensors?
As to propulsion at TL7 without fission, don't launch from the surface if the ship is intended for long duration travel, use a shuttle for ground side interaction.
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Re: Low tech ships - Need help

Postby DivineWrath » Mon Nov 27, 2017 4:08 am

Well, my next problem involves carriers and fighters.

There doesn't appear to be a single place that stores all the rules for launching and docking ships. More often, it seems to be the various ship modules that contains pieces of information I'm looking for. In fact, one such module seems to contradict itself, the docking space says it takes 1D minutes to dock or leave, but then later says it takes D3 rounds to recover or release a ship of 2000 tons or less, larger 1D rounds. It is my understanding that both D3 rounds and 1D rounds are ship combat rounds and therefore takes up more time than 1D minutes.

My other problem is the launch tubes are TL 9, which is above the tech I'm working with. I'm right now thinking of making a low tech version for TL 7 ships. Maybe launch tubes that are good for only 1 ship at a time, and maybe a quarter of the size of launch tubes. So 2.5 times the size of the ship.

Any thoughts?
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Re: Low tech ships - Need help

Postby Condottiere » Mon Nov 27, 2017 10:35 am

My take is that launch tubes are some form of low powered mass driver, considering no provision is ever taken for odd shaped configurations, only for volume.

Also, I calculate one launch per thirty six seconds, without a physical catapult, though the spacecraft were probably manipulated into position by cranes.

Can you make a low tech variant? Probably, but you'd have to take into account the available technologies, maybe some form of an actual physical catapult that slows down launch times.

Docking mileage probably varies, taking your leave is probably easier than trying to get back in. The larger the receiving bay, the less you have to worry about scratching the paint.
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Re: Low tech ships - Need help

Postby AnotherDilbert » Mon Nov 27, 2017 11:52 am

DivineWrath wrote: Well, my next problem involves carriers and fighters.
The most efficient way to carry fighters is outside the hull with Docking Clamps. To enable maintenance and repairs you probably want a few Full Hangars or a small Construction Deck.

The Fighters can carry Forced Linkage Apparatus and attach themselves to any suitable ship for transport.

Don't forget UNREP equipment to be able to resupply the fighters.

I don't see much need for Launch Tubes or Recovery Decks. They are very expensive and have very few use cases. Even without them you can still launch and recover all craft in a few minutes.
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Re: Low tech ships - Need help

Postby Condottiere » Mon Nov 27, 2017 8:27 pm

Depends on the size of what you would define as fighters.

With the current range restrictions, I think a heavy fighter is hundred tonnes plus.

Makes them less fragile and needy for hangar time, so optimal for clamping.
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Re: Low tech ships - Need help

Postby DivineWrath » Tue Nov 28, 2017 2:18 am

Since it might be relevant...

My TL 7 light fighter is a 10 ton ship with single cockpit, armor, and a fixed mount autocannon.

My TL 7 heavy fighter is 40 ton ship with a double cockpit, armor, and a heavy cannon barbette.

Both have enough ammo and fuel reserves to last many hours in combat.

By the way, single cockpit with fixed mount, does the pilot suffer a penalty for controlling movement and the fixed mount?

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