09-22-2018, 08:03 AM | #1 |
Join Date: May 2010
|
[Spaceships] Proposal for building missiles as spaceships
Here's a rough draft of a proposal for building missiles as spaceships. Feedback welcome.
Missiles are built as spaceships from SM+0 (0.1 tons) to SM+3 (3 tons). In the interest of preventing small missiles from being ridiculously cheap, while maintaining smooth continuity with the cost of SM+4 drones, missile systems cost 2% of the cost of an equivalent SM+6 system at SM+0, 3% at SM+1, 5% at SM+2, and 7% at SM+3. Control "rooms" cost $10k regardless of size (miniaturized electronics are expensive!), and have no control stations. A control room can be designated a missile guidance unit. If this option is chosen, the missile still functions mostly like a spaceship, but is controlled with Artillery (Guided Missile) of a gunner on the launching ship, modified by Handling (not sAcc!). Missile guidance units do not provide computer networks or sensor arrays, and only provide a minimal comm system to receive orders from the launching ship. The launching ship's array may be used to defeat Defensive ECM. A control room must be designated a missile guidance unit if it would have a computer network rated less than C1, or less than a level 1 common/sensor array, given the size and TL. Missiles can have most system types, but not weapons. Armor that would provide less than 1 dDR per system is prohibited, except streamlined missiles can always have a single Light Alloy system as a "nose cone". Fission reactors and engines are unavailable. Fusion reactors and engines have minim SM+2 and minimum TL10. Antimatter reactors and engines are unavailable through TL10, have minimum SM+2 at TL11, and can be any size at TL12. Missile launchers work like hangar bays, but are priced as major batteries, and by default have a number of control stations equal to the number found in a same-size control room. They get the same discount for removed control stations as a control room. I'll post some worked examples later. |
09-22-2018, 09:10 AM | #2 |
Join Date: May 2010
|
Re: [Spaceships] Proposal for building missiles as spaceships
Now some worked examples: first, a very generic chemical missile (can be any SM and TL):
Front Hull [1-6] Fuel Tanks [core] Control Room Central Hull [1-6] Fuel Tanks Rear Hull [1-2] Chemical Rocket Engine [3-6, core] Fuel Tanks Performance: 6G acceleration, 5.61 mps delta-V. Costs $28.3K for the SM+0 version, $37.5K for the SM+1 version, $56.2K for the SM+2 version, and $75.7K for the SM+3 version. These costs include the cost of rocket fuel and are rounded to the nearest $100. These missiles must be remote-guided at TL8. At TL9, a SM+3 drone version becomes available, and minimum drone size decreases by 1 per TL thereafter. |
09-22-2018, 09:49 AM | #3 |
Join Date: May 2010
|
Re: [Spaceships] Proposal for building missiles as spaceships
Here's a sophisticated drone missile, likely to be a mainstay anti-capital ship missile at TL10. It's built on a 1-ton (SM+2) unstreamlined hull.
Front Hull [1-4] Nanocomposite Armor (Hardened; 8 dDR) [5] Tactical Array (comm/sensor 3) [6] Defensive ECM [core] Control Room (C5 Computer, comm/sensor 1) Central Hull [1] Nanocomposite Armor (Hardened; 2 dDR) [2-3] Defensive ECM [4-6] Fuel Tanks (0.05 tons fuel pellets providing 5 mps delta-V each) Rear Hull [1] Nanocomposite Armor (2 dDR) [2-6] High-Thurst Fusion Pulse Engine (0.1G acceleration each) [core] Fuel Tank (0.05 tons fuel pellets providing 5 mps delta-V) Performance is 0.5G, 20 mps delta-V. Cost is $766k |
09-22-2018, 11:43 AM | #4 |
Join Date: Feb 2016
|
Re: [Spaceships] Proposal for building missiles as spaceships
Well, one problem is that it reduces the cost of missiles by a minimum of 50%, which would be balanced by the fact that their performance would be atrocious, lacking the thrust and/or delta-v to be a threat to anything but stationary targets. For example, a TL9 SM+0 missile constructed as a spaceship would have a Complexity 2 computer in its control room, making it less capable than the average TL9 Tiny Computer.
|
09-22-2018, 02:06 PM | #5 |
Join Date: May 2005
Location: Oz
|
Re: [Spaceships] Proposal for building missiles as spaceships
Are you going to define some warhead systems?
__________________
Decay is inherent in all composite things. Nod head. Get treat. |
09-22-2018, 05:39 PM | #6 |
Join Date: Aug 2007
|
Re: [Spaceships] Proposal for building missiles as spaceships
Are you trying to reduice missile performance by adding uneccessary components? :)
5.6 to 20 miles per second makes the missiles themselves more formidable than any chemical explosive warhead and effective enough that nukes are only useful if contact can not be achieved.
__________________
Fred Brackin |
09-22-2018, 05:49 PM | #7 | |
Join Date: May 2010
|
Re: [Spaceships] Proposal for building missiles as spaceships
Quote:
Not being able to do proximity detonation is a bit of an issue issue, but doesn't matter much for large targets. You could fix it with a warhead system, as mentioned by Agememnos, though that would further degrade performance. I've thought about something like, "when ramming, you get a +4 bonus and possibility of multiple hits, but halve damage" for conventional fragmentation warheads. Nuclear warheads would require a bit more thought. The missile cost problem strikes me as really, really hard. It's hard to see how to justify a 4-ton missile costing $4 million while an SM+4 drone with only slightly worse performance comes in under $1 million. I've tried to do things in a way that allows for a somewhat smooth transition from small, high-cost-per pound missiles to big, lower cost-per-pound ones. But I wonder if this discrepancy between spaceship costs and missile costs is a result of mixing up costs of mature technologies vs. cost of cutting-edge military hardware. For example, in the real world missiles can indeed cost $1 million / ton, but Wikipedia suggests a price tag for an F-15E that's almost that high ($31.1 million for a bird with a MTOW of 36.7 metric tons). |
|
09-22-2018, 05:50 PM | #8 | |
Join Date: May 2010
|
Re: [Spaceships] Proposal for building missiles as spaceships
Quote:
|
|
09-22-2018, 10:16 PM | #9 |
Join Date: May 2010
|
Re: [Spaceships] Proposal for building missiles as spaceships
Another sign Spaceships is being really optimistic about costs in a way that isn't carrying over to missiles: Spaceships 2 lists the cost of upmass at TL8 at $300,000 per ton, which is about $300 per kilogram, which we are not close to if you know anything about real-world space launches. But the book has a perfectly legal HLV build that supports this! So one option: much cheaper missiles, all Spaceships costs are understood to be an ideal for a very mature technology, GM is welcome to slap a 10x surcharge on anything deemed less than fully mature, which might be a lot of military hardware.
|
09-22-2018, 10:24 PM | #10 |
Join Date: Aug 2004
Location: Wellington, NZ
|
Re: [Spaceships] Proposal for building missiles as spaceships
Spaceships itself notes that prices for limited run ships can be 100-1000 times the calculated price. Military spaceships are probably limited run, though not that limited. Missiles, OTOH, probably aren't really 'limited run' items.
__________________
Rupert Boleyn "A pessimist is an optimist with a sense of history." |
Thread Tools | |
Display Modes | |
|
|