SWM wrote:The Cataphract is not an SDM. An SDM is a Single Drive Missile. Long-range SDMs have existed in every navy for decades. Remember the Haven-designed ground-based missiles at Blackbird? That is an example of a classical long-ranged SDM. It had a range even longer than capital missiles of the time. That's the kind of thing that was used for system defense before MDMs and pods. There were probably also space-based versions--too large to carry on ships but good for system defense.
Ok, I initially screwed up by misreading a velocity as an acceleration

, but once I got myself straightened out I did a little number crunching on the ground-based missiles we saw in HotQ.
We've got a few pieces of information about them:
* Burnout velocity is "117,000 KPS"
* Burnout range is "eight-million-plus kilometers"
* The ones launched at Fearless are clocked at "eight-three-three KPS squared" (85,000g); and still have "one-three-five seconds" left until (powered) impact.
* Finally, "The attacking missiles’ powerful drives gave them an incredible velocity—they were already moving fifty percent faster than anything of Fearless’s could have managed from rest".
Given that acceleration the burnout velocity and range both give about a 140.5 second burnout. That's in between a normal missile's 60 seconds at 100% power or 180 seconds at 50% power. So I assume the missiles are paying for their much higher than normal acceleration with reduced drive life.
The only bit that doesn't entirely track is the relative velocity, because Fearless should have missiles that are good for at least 85,000g at 100% power
(certainly the CL Fearless did in the previous book). So the relative velocity would either be identical, or if Fearless was firing at 50% power setting would be 100% higher (not 50% higher). However there are still two different ways it might work, both relying on the missile's dissimilar endurance numbers.
Method 1 - compare to the CA missile at 100% power, at some point after it burns out; but the Ground missile is still accelerating. You'd hit a 1.5x velocity advantage at about 90 seconds into the flight; 30 seconds after the shipboard missile burned out. (Kind of odd way to compare, but the quote did say "already moving" implying the missiles were continuing to accelerate.
Method 2 - compare 50% power CA missile to Ground missile after each has burned out (at 180s and 140.5s respectively). The burnout velocity difference is 1.56x after both finish their powered runs.
I'm thinking that basically the Havenite missile's 85,000g
is their 50% power level, but it's good for about 40 less seconds than a normal missile. That gives 8.2 million km range at that power setting, significantly more than the 6.7 million km powered range of a normal missile of that era at 50% power setting.
(That being said, if 85,000g is the 50% power setting that ground bases missile's 100% setting is quicker than any missile or CM I believe we've seen to date; though I don't have my full missile spreadsheet handy)However given those specs I'm
really surprised that we didn't see those overpowered missiles deployed in a pod based format at any point during the 1st war.
Sure, you could cram in less per pod, but if I figured their numbers correctly they'd had a nice range advantage and an impressive 50% terminal velocity advantage over a pod of 'normal' capital ship missiles.
Just to compare though, those numbers are far short of what I think the max range and endurance of a Mark 14 ERM / Mark 36 LERM missile is good for; ditto for the Technodyne pod missiles used at Monica - those seem to have basically the same acceleration numbers of a similar era single drive (non-ERM) missile, but have higher drive endurance.