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Post by elouda on Feb 19, 2017 11:55:10 GMT
What's the deal on Boron Carbine / Boron Nitride? I presume I should refrain from using these given that Boron itself is in the 'restricted materials' section?
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Post by elouda on Oct 21, 2016 14:27:58 GMT
Maybe do a cutoff date and then a separate poll thread to vote on the submissions? We could then do various rounds with different rules - higher cost limits, weight limits, tech limits (chemical engines only?), etc.
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Post by elouda on Oct 21, 2016 0:51:32 GMT
I think no mass limit is fine. Mass has its own inherent cost in terms of delta-V and acceleration.
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Post by elouda on Oct 20, 2016 23:50:59 GMT
Love the idea. Are there any rules regarding 'glitched' modules? I don't mean the overly efficient rail/coilguns (which atleast are internally consistent to some degree), but specifically the ones that break the integrator for those modules intentionally to produce the 100km+ 'laser' guns.
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Post by elouda on Oct 19, 2016 15:56:59 GMT
The main issue with really big guns right now is that the reaction wheel style turrets for them don't really work. The largest I've been able to use within reason was a coilgun firing 75kg shells, but beyond that I couldn't make a sensible design. This thing still fired several rounds per second though.
My most successful gun design at the moment is a 150mm firing a 5kg round, which I suppose would be more of an 'intermediate' weapon, with a rate of fire like 20 rps.
As for energy/momentum - there's a few things to consider here; 1) Heavier shells have upsides in atmosphere as they retain velocity better due to their energy/momentum ratio being smaller, this is not a factor in space 2) Energy/momentum ratio and sectional density has a large role in penetration, but its important to remember that a lot of 'conventional' wisdom ceases to apply once our projectiles are doing 5-6km/s instead of 700-1200m/s. 3) Lastly, the biggest advantage to energy over momentum is of course the fact that you get more muzzle velocity for the same energy, which means less travel time and hence (generally) more accuracy. This is less of a factor in atmosphere as resistance scales approximately as a square, so you give up that velocity rather quickly (though see point 1 above), but in space thats going to be maintained all the way to the target.
I think once the coil/railgun efficiencies are fixed, there's going to be some -very- interesting choices to make. As an experiment, I adjusted the stock Corvettes guns until they were around 80% efficient, and the 286mm was only firing every 5-6 seconds if I recall.
I think that larger flak rounds may be a very interesting option for larger guns once we have more control over the proxy fuzes. It would also be nice for larger guns to be able to have multiple types of shells for different situations.
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Post by elouda on Oct 19, 2016 5:34:36 GMT
I used a missile/nosegun 371 ton 'drone' as part of my third generation designs. It actually originated as an attempt at a 'light' capital ship / fast attack craft in the 500-600 ton range, but the crew requirements killed it, as they were like 75% of those of my regular capital ships. Instead I removed the crew quarters and ended up with that.
childrenofadeadearth.boards.net/post/1166/threadI haven't revisited the concept of drones that big in either my fourth or fifth generation designs, though it might be time to do so. Given that the carrier was only carrying 7-8kt of drones, I figure something half the size could have done the same if one was willing to be a lot more frugal in other respects. Also, on the general topic of flares and missile avoidance - a 'decoy drone' deliberately engineered for massive energy output is often the better solution. It can be deployed before the battle (or several can) and then told to scatter. If any survive, refuelling them would allow 'reusability' to a degree. As for general 'missiles rule concept' - yes, but I think its hard to determine how effective anti-missiles really could be given the limits of the AI and the proxy fuzes still being a little lacking at the moment. I forsee that the current 'paradigm' if you will of missile dominance might certainly be true against non-antimissile armed opponents, but two equivalently armed forces would probably exhaust their magazines without much result (somewhat akin to what I expect a lot of larger surface vessels would do today) and then either call it a day, or decide to get into closer combat. There are a couple of other factors were missing too that would favour 'gun/lasership' designs; 1) No logistics and hence no ammo to worry about (long term) - this is particularly a concern if my statement above turns out to be true 2) Costs only account for raw materials, not construction/manufacturing work
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Post by elouda on Oct 19, 2016 2:23:54 GMT
You could just use dry mass without including tank dry mass or cargo pod mass.
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Post by elouda on Oct 18, 2016 6:14:49 GMT
Yeah, a lot of the design decisions would have entirely different considerations if we had to think strategically and consider things like logistics, supply and maintenance in that kind of setting.
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Post by elouda on Oct 18, 2016 5:01:24 GMT
Started experimenting with mixed fuel propulsion, using a single Hydrogen Deuteride core thruster for orbital maneuvers backed by a number of Semiheavy water engines for in combat maneuvering. So far the results have been rather impressive, compared to either pure Decane or Semiheavy water craft (I don't consider HD viable on its own for anything besides transports or carriers as the volume is horrid). This the 'baseline' hull for the ~8.5-10kt Frigate class based on these. They have 12.3km/s dV if using only the HD engines, and 6.22km/s when running the SHW combat engines. Close up of the 'business end' of this design. The core engine is a 9.2km/s 5.1MN HD NTR with 15 degrees of gimbal (allowing to act as an additional maneuvering thruster in combat). It has 400t of HD fuel, and with this engine only, the acceleration is around ~61 mg. The combat engines are six 4.46km/s 10.1MN SHW NTRs with 55 degrees of gimbal. They are supplied with 5850t of fuel. The large gimbal angles and solid (though less than I prefer, I generally aim for 1-1.2g) thrust gives this thing very impressive maneuverability in combat. Unfortunately there's a few major issues with it, mainly that the combat thrusters like to thrust at odd angles wasting a lot of dV, and the dV display is occasionally somewhat odd when running with some engines off.
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Post by elouda on Oct 12, 2016 16:29:18 GMT
The kinetic energy per projectile is KE = 0.5 x M x V x V where M is the projectile mass in kilograms (so 1g is 0.001kg) V is the projectile velocity in m/s (so 5.4km/s is 5400m/s)
The power output of the gun is P = KE / D where D is the delay between shots in seconds (so 23ms is 0.023s)
As a worked example, take the stock 13MW 286mm; KE = 0.5 x M x V x V In this case; M = 10kg V = 5.14km/s = 5140m/s Therefore; KE = 0.5 x 10 x 5140 x 5140 KE = 132098000J = 132.098MJ
As for power; P = KE / D Here D = 125ms = 0.125s Therefore; P = 132.098 / 0.125 P = 1056.784MW = 1.056GW
As the gun has an input power of 13MW, this gives an efficiency of (1056.784/13) * 100 = 8129%
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Post by elouda on Oct 12, 2016 16:09:36 GMT
Not deuterium, but this is my current primary thruster for all designs over ~75kt. Smaller than that and I prefer to use a smaller 60MN design.
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Post by elouda on Oct 11, 2016 9:47:11 GMT
I've settled on using the same kind of 'double broadside' arrays myself recently, seems to work out better than massive frontal laser arrays.
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Post by elouda on Oct 6, 2016 16:53:12 GMT
Its also a glitched design.
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Post by elouda on Oct 6, 2016 14:37:53 GMT
If flak rounds reliably detonated before passing their targets, a lower velocity coilgun firing flak rounds that split into thousands of gram or small chunks might make a very effective defence.
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Post by elouda on Oct 6, 2016 8:12:24 GMT
Dhan,
Logically that would be more effective, but because missiles go 'dud' the instant their dV hits zero, what will happen is when you re-enable them closer to the target, they will but the dV left in a matter of seconds, on an accelerating (rather than correcting for impact) trajectory, and then go dud and not go off at all in most cases.
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