Arctic Fox, on 10 May 2012 - 08:52 AM, said:
I already (sort of) explained my comparison a while back, didn't I? A Type III nuclear weapon in the BattleTech universe is a 50-kiloton weapon. A direct hit in space by one of these causes 100 points of capital-scale damage. A Heavy Mass Driver shot delivers 140 points, so its impact is more or less equivilant to about 1.4 50-kiloton nuclear weapons. From that we can more or less derive the energy output of other weapons.
Actually, it's not a perfect comparison, since only about half the actual energy of the nuclear weapons goes into the target, but that can be accounted for as well.
EDIT: Actually, this was the original comparison to the MAC. One could more easily directly say that one kiloton is equivilant to 4 points of capital-scale damage, assuming half the energy of BattleTech's nuclear weapons go into the target.
Actually, it would be less than half, even for a direct surface hit, unless the warhead penetrated well into the ship before detonating. Even if it hit a flat hull kilometers across in each direction, less than half the energy would be absorbed by the target, as a lot of the energy would be reflected or re-emitted back out into space before all its work had been delivered to the target, and since these ships aren't Borg Cubes, the profile of the ship would catch less than half the sphere of energy released. 5 points of capital-scale damage per kiloton, or about 0.837 TJ per capital-scale damage point, would be more accurate based on this comparison.
That gives the HMD, at 140 capital-scale damage, a kinetic energy equivalent to about 117 TJ, or 28 kilotons.
A Heavy Naval Gauss does 30 points of capital-scale damage, a kinetic energy equivalent to about 25 TJ, or about 6 kilotons.
A Medium Naval Gauss does 25 points of capital-scale damage, a KE equivalent to about 20.93 TJ or 5 KT.
A Light Naval Gauss does 15 points of capital-scale damage, a KE equivalent to about 12.56 TJ or 3 KT.
A Heavy Naval PPC does 15 points of capital-scale damage, and so delivers about 12.5 TJ of energy.
A Medium NPPC does 9 points of capital scale damage, or about 7.53 TJ of energy
A Light NPPC does 7 points of capital scale damage, or about 5.86 TJ of energy
A NAC/40 does 40 points of capital-scale damage, and so delivers about 33.48 TJ of kinetic energy, the equivalent of about 8 KT.
A NL55 (naval large laser) does 5.5 points of capital-scale damage, or about 4.19 TJ (just over a KT worth of energy).
Now, it is very much worth noting that the Covenant ships appear to be decidedly vulnerable to weapons yields in the dozens of megaton range, as the Battle of Onyx saw several Covenant ships destroyed and damaged by a minefield consisting of 14 HORNET mines, each with a yield of 30 megatons. 16 ships entered the minefield, with 12 destroyed outright and 4 crippled. That puts the bending-over-backwards maximum energy to destroy a Covenant ship (we will assume of the Destroyer variety, as they seemed to the majority of the ships in that the fleet, though the exact composition of the 16 remaining Covenant Seperatist ships at that time is not listed clearly in the Halo wiki article) at 26.25 megatons, or 109.83 PetaJoules, assuming all 16 ships absorbed 100% of the energy from those 14 mines, which is extremely unlikely. At most, they would have absorbed half of it under absolutely ideal conditions, and more likely a quarter or less of the energy was absorbed by the Covenant ships. So 7.5 MT / 31.38 PJ - 13.13 MT / 54.94 PJ to out-right destroy a Covenant Destroyer. We'll go with the lower energy figure for a mission-kill, since much more energy than required to mission-kill the ship would have been absorbed across the length of it. So that's 31.38 PJ, or about 7.5 MT, to mission-kill a Covenant Destroyer, with shields. Single shots that concentrate energy into a much smaller area also appear to be able to achieve mission-kill results from a critical-hit penetration with much lower energy yields, particularly against unshielded Covenant ships, though with shields the minimum energy for a mission-kill against a Covenant Destroyer even with shots that delivery large amounts of energy in a concentrated area is likely still in the 1 megaton / 4-5 PJ range (though this may be further reduced by the use of rapid-fire high-energy shots to overwhelm the Covenant shields).
Arctic Fox, on 10 May 2012 - 08:52 AM, said:
Where do you get that BattleTech reactors are limited from generating large amounts of power? As I was saying, any energy system, antimatter included, is limited in its ability to produce power by the capabilities of the reactor. If BattleTech ships used antimatter, they would be limited by exactly the same factors. Your whole argument seems to be dependent on the notion that all of BattleTech's systems except transit drives have pathetic energy output, so, again, what do you base that on?
Well, compared to what M/AM-powered systems are capable of, they do. The McKenna class WarShip is equipped with 12 NL55s and 48 Heavy NPPCs (it also has 12 NAC/40s and 6 AR-10 launchers, but they don't draw the majority of their output from the ship's reactors). That is a single-shot output of (12 x 4.19 TJ) + (48 * 12.5 TJ) = 650.28 TJ. Sarna doesn't list cycle times on these weapons, but assuming 3 seconds to cycle the equivalent of a full salvo (probably longer than that, especially when you factor in heat management over prolonged battles), that's 216.76 TeraWatts. Round that up to 300 TeraWatts for all ship systems not including drive engines, for the sake of a conservative and round number. To achieve 300 TeraWatts of energy output, a fusion reactor would have to convert 300,000,000,000,000 J / 90,000,000,000,000,000 = 0.00333 kg, or 3.33 grams of matter to energy per second. Since at maximum theoretical efficiency, a fusion reaction converts 1% of the fuel mass into energy, a fusion reactor would have to 'burn' 333 grams of fuel per second. Allowing for less than maximumum theoretical reaction efficiency, a BT fusion reactor would have to 'burn' about 0.35 kilograms of fuel a second to maintain the McKenna's full weapons output.
Per your own figures on the Whirlwind class Destroyer's tuns-per-burn-day, a Whirlwind will burn 0.457 kg of fuel a second under constant acceleration of 1g. This is within the bounds of the 0.35 kg of fuel per second to maintain the McKenna's systems output, including full weapons capabilities, and excluding main drive expenditures. The fuel burn rate listed for engine outputs is in the same range as those listed for weapons outputs, which is well within the capabilities of an advanced fusion reactor (or, more likely, multiple fusion reactors on ships that big).
Compared to M/AM power, however, these energy amounts are miniscule. With the same amount of fuel consumed, a M/AM-powered starship can achieve 100 times the energy output. Compared to advanced M/AM-powered civilizations, like the TNG-era Federation in Star Trek, low- to mid-TeraJoule energy outputs for capital ships is pathetic. A single Federation photon torpedo has a M/AM warhead with a standard yield four to five HUNDRED times the output of all of the McKenna's energy weapons, and the Federation throws them around like candy. Capital ship energy weapons throw out dozens to hundreds of PetaJoules per shout, about a thousand times greater than the McKenna's energy weapons.
Now, the McKenna's armaments are nothing to sneeze at for a fusion-powered civilization, and they're pretty respectable for an advanced, fusion-powered civilization that isn't breaching into absurd fuel burn rates, but compared to a M/AM-powered civilization, they are pretty paltry (though, point in their favor, the Covenant's weapons outputs and shield/hull endurance are pretty damned paltry for a M/AM-powered civilization, such that they're not all that much better than a decent fusion-powered reactor system).
This is in stark contrast to the performance of their main drive engines, which burn 0.457 kg of fuel and get the work of 457 kg worth of fuel. As Catamount noted, it is much more parsimonious to say that their engines simply employ some sort of mass reduction or other 'magical' system to get more acceleration out of the fuel they burn than they otherwise should.
Arctic Fox, on 10 May 2012 - 08:52 AM, said:
As for Covenant technology that (seemingly) violates established physics. Look no further than energy shields (conservation of momentum), inertial compensation (likewise) and faster than light travel (relativity). Any more?
There is nothing about shield technology that violates conservation of momentum - incoming particles are deflected or their energy absorbed and channeled elsewhere (though shields usually do the deflecting bit rather than the absorbing bit). A ship struck by a MAC round should not be hurled sideways unless the ship that fired the MAC round is hurled backwards. Since MAC rounds do not impart significant negative acceleration on a UNSC ship, we should not expect to see significant acceleration imparted to a Covenant ship when a MAC round stricks its shields.
Inertial compensation does not violate established physics, as there is nothing in established physics that prohibits the manipulation of gravitational fields to negate inertial effects - we just don't know how such manipulation would be done.
Furthermore, faster-than-light travel is not expressly forbidden by Relativity - what is forbidden is acceleration to and beyond lightspeed. There is nothing in Relativity that says something like slipspace can't exist, nor in other physics, just that we have no knowledge of how it might work or to manipulate it or even determine if it does or does not exist.
Arctic Fox, on 10 May 2012 - 08:52 AM, said:
Oh, and surely you can't compare the devestation that will be caused by tons of antimatter losing containment to the comparatively tiny release of energy caused by a BT's fusion engine being breached, right?
Actually, tons of anti-matter losing containment wouldn't be quite so energetic an event as most people tend to think. An anti-proton will only annihilate when it comes into contact with a proton - it will not undergo any annihilation upon contact or interaction with a neutron or an electron. The same goes for an anti-neutron or a positron. Losing anti-matter containment would be a very major problem, but the reaction rate of a bucket of anti-deuterium slush with a metal wall would be pretty low - it would be energetic, and given enough time you'd eventually annihilate the whole mass of anti-deuterium, but it would not be anywhere near instantaneous, unless you dumped in another bucket full of regular deuterium slush.
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Another thing a lot of people tend to forget is laser blooming can be controled to an extent. One reason NASA got funding for the Keplar Space Telescope was the Air Force wanted to use the mirrors on a Anti-ICBM laser sat that would do BT small laser damage at 5000km range( the chem-fueled laser generator was bench tested a decade ago ). The SLDFs Capital lasers are range restriected only by the size of the optics used to focus them.
