FALL 1924: Missile possibilities

ThinksMarkedly wrote:The point I was making is that such a long-range and surprise engagement (like Operation Fabius and the Battle of Beowulf) would require more than higher acceleration missiles. I'm not dismissing them as useful; I'm saying they're not the silver bullet.

I was unconfusing your previous post not arguing against or for the rest of your post... and this post you did is better to discuss than the previous.

Not stated, but I was assuming, everyone would have FTL missiles, and same equivalent tech as the RMN etc. After all this is about designing, new for the future(not that they will at this point of 1924 as too many irons in the fire). This is more of a --> Future.

ThinksMarkedly wrote:I was considering a surprise attack because on any other condition, the defenders could have fired earlier, negating the advantage of a higher-acceleration missile. This scenario was driven by the fact that you were talking about 4-stage system defence missiles. And as I said, the defence missiles don't need to be launched from the location of the attacker's target, so they won't have the same distance to overcome.

If surprise attack, then no, the defenders missiles will not arrive first as no one is firing until anyone passes the hyper limit as it is utterly pointless to do so. Disappear into hyper. ]Of course with FTL missiles does anyone have to ever cross the hyper limit? This means the attacker is going to sit on their ass scouting out all those pods which are not stealthy enough to not be found by equivalent RMN RD's.

ThinksMarkedly wrote:But that won't necessarily negate the Apollo FTL link. Everyone else's accuracy sucks at 65 million km.. or 75, or 225, while Apollo's is acceptable. That means the side with Apollo can afford to start firing from a much bigger range and that's the range that the battle will start at (both sides know this). But if both sides fire roughly the same number of missiles, the Apollo ones will do far more damage, despite arriving later.

See previous comment, both sides will have Apollo control missiles.

PS: FTL... effectively means missile duals instead of being at 3 light minutes could be at 3 light hours... Which means Missile duals using this range will not happen as that is WAAAAAYYYY beyond the hyper limit so different technologies etc MUST be implemented before everyone has FTL to make system defense even partially viable.

Relax wrote:Not stated, but I was assuming, everyone would have FTL missiles, and same equivalent tech as the RMN etc. After all this is about designing, new for the future(not that they will at this point of 1924 as too many irons in the fire). This is more of a --> Future.

Well, then this changes the whole calculus. If two missiles are equal in every aspect, except for the acceleration, the one with the higher acceleration wins.

I suspect that cracking the FTL control link and the ACM AI is a far more difficult challenge than the 84,000-gravity acceleration. I don't have proof for this, only a feeling. But if I'm right, then the side with Apollos gets 84,000-gravity missiles before the side with 84,000-gravity missiles gets Apollo.

Relax wrote:All valid points, though one NIT: MK23 still has the 48,000G at 180s of its predecessors. It is only the MK16 with its 46,000G. By playing with the numbers it is also apparent that the LERM also has a 46,000G.

It should be noted that early in the war, missile accelerations were lower than the above numbers. In the case of PN, MUCH lower. Same goes for the Javelin missile for the SLN.

Still begs the question: What has to happen to an impeller node to go from ~45,000G@180s to 84,000G@215s even if said missile is several times larger than the other. 84,000G is what the PN missiles could do in HotQ IIRC for 60s and I think RMN missiles could hit?? 94,000G for 60s as well? Hrmm.

The first time we heard of specs for the SLN's Javelin was in Storm from the Shadows -- where we're told "Acceleration forty-six thousand gravities! [...] That was six-teen hundred gravities lower than a Javelin, but a Javelin’s maximum powered endurance at that rate was only three minutes, with a terminal velocity of 84,000 KPS from rest and a powered enve-lope of only 7,575,930 kilometers" (And this was from a SLN office shocked that Rolands had firing 46,000 g Mk16s at them at 36.7 million km; with a 5.9 minute flight time)

That puts the Javelin at 47,600 gees for 180s or 95,200 gees for 60s.

Now the missiles the ex-SLN Monican BCs were firing were crap in comparison. Those were "Those missiles' powered range envelope from rest generated a maximum range of just over 5,900,000 km, with a terminal velocity of 66,285 KPS" [SftS]. That equates to "just over" 37577 gees for 180s (or 75,154 gees for 60s) -- which is worse that Manticore's pre-war missiles; which each seem to have 42,500 gees for 180s. [Also RFC has an infodump from 1998 were he claims that Manticore's capital missiles had "marginally higher maximum acceleration (95,000 gravs versus 85,000), which equates to a small but significant advantage in maximum attack range". That would push their maximum half-power accel from 42,500 to 47,500 and range from 6,747,300 km to 7,541,100 km]

Mind you, late October 1998 means that's after he's written Echoes of Honor, and in the earlier Honor Among Enemies it says "the RMN's latest capital missiles accelerated at 92,000 KPS²" [which I assume is a typo and should be "gees" -- otherwise that's over 100x improvement in acceleration]. So his infodump might just be implying that the CA/BC missiles haven't (yet?) benefited from the wartime improvements that capital ship missiles have.

Also "Cerberus was a rear-area system whose primary defense had been that no one had the least idea how to find it. Its missiles were the same ones it had been given before the war began, with standard prewar drive options and a maximum acceleration of eighty-five thousand gravities. But by dialing the birds' acceleration down to half that, endurance could be tripled from sixty seconds to a hundred and eighty . . and range from rest at burnout upped from one million five hundred thousand kilometers to approximately six million seven hundred and fifty thousand" So the Peep's pre-war missiles at Cerberus were 42,500/82,000g 180s/60s birds -- so less capable than the ground launches ones they gave to Blackbird base which could do at least 135 seconds at 85,000 gees (rather than the 60s their normal missiles could)[1]

"If those missiles had the endurance she estimated, they would accelerate to an incredible 117,000 KPS and reach eight-million-plus kilometers before burnout. “Birds closing at eight-three-three KPS squared. Impact in one-three-five seconds—mark!”"

If those Blackbird missiles had a half-power mode (and it's possible that, like CMs, they don't; as trade-off for their extra performance) that would push their endurance to 405 seconds and range out to 33,756,345 km.


As for Manticore/Grayson's MDMs; I'm just not seeing the higher acceleration for Mk23s; though its there for the older missiles.
1st war:
180s @ 46,000g WDB's initial planned designs
180s @ 47,500g 8th fleet's SD(P)s at Basilisk
180s @ 47,520 KPS2 [sic] Elric Picket (max stated as 96,000g)
180s @ 48,000g RMN Barnett attack
--- So far so good, barring the g/KPS^2 and likely "2" for "0" typos in the Elric situation. And these are all older capacitor powered designs; like the Mk41. ---
2nd war and beyond:
180s @ 46,000g Zanzibar's outer platforms [AAC]
180s @ 46,000g Honor's Apollo missiles BoM against Chin [AAC]
180s @ 46,000g Beowulf's Apollo pods [UH]
180s @ 46,000g Honor's Apollo missiles at Ganymede [UH]

I guess Zanzibar's system defense MDMs could have been very early stock capacitor missiles with the original acceleration; but Honor's and Beowulf's were explicitly Mk23 Apollo pods.

You're right that all Mk16 references have been for 46/92k gees (except at Hyptia where for some reason at least Phantom's initial salvo was at 45,500 gees); but all Mk23 references I can find are also 46/92k gees (or 451/902 KPS^2; which rounds to the same thing) -- despite the older MDMs being quicker.

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[1] Actually based on the expected 117,000 KPS burnout velocity they'd actually need 141 seconds endurance, not the 135 time to expected impact, unless the groundside launchers could impart 4,546 KPS velocity. But I did my calculations with the observed 85,000 gees for 135 seconds

Jonathan_S wrote:
That puts the Javelin at 47,600 gees for 180s or 95,200 gees for 60s.

Now the missiles the ex-SLN Monican BCs were firing were crap in comparison. Those were "Those missiles' powered range envelope from rest generate

Holy cow, man, you did what I keep telling myself to do as I read the books. Write down the numbers in an excel spread sheet. Big Kudos.

Don't mind me, I'll just steal your post and put it in my notes.

Relax wrote:

Jonathan_S wrote:
That puts the Javelin at 47,600 gees for 180s or 95,200 gees for 60s.

Now the missiles the ex-SLN Monican BCs were firing were crap in comparison. Those were "Those missiles' powered range envelope from rest generate

Holy cow, man, you did what I keep telling myself to do as I read the books. Write down the numbers in an excel spread sheet. Big Kudos.

Don't mind me, I'll just steal your post and put it in my notes.

Why not just steal his spreadsheet outright? https://docs.google.com/spreadsheets/d/ ... sp=sharing

I check it sometimes when I come up with a half-baked idea... and then end up throwing out my drafted post entirely.

So yes, the RMN's countermissiles can do 130,000g for 60 seconds, generating a relatively simple 25% of C. You slap three of those drives together and you've got .75c achievable in 180 seconds. The Havenite MDM needs 540 seconds to do that!

Relax wrote:

Jonathan_S wrote:
That puts the Javelin at 47,600 gees for 180s or 95,200 gees for 60s.

Now the missiles the ex-SLN Monican BCs were firing were crap in comparison. Those were "Those missiles' powered range envelope from rest generate

Holy cow, man, you did what I keep telling myself to do as I read the books. Write down the numbers in an excel spread sheet. Big Kudos.

Don't mind me, I'll just steal your post and put it in my notes.

I need to clean up and update the spreadsheet (for example UH wasn't in there; those numbers for my post came up in a text search). But yeah - ship acceleration and missile performance were a couple of deeprabbit holes I went down several years back which resulted in spreadsheets worth of data.

My helpfully named _Missile_Survey.xlxs sheet has 80 rows of missiles (though a number of entries are 2 rows as the text explicitly gives both full and half power info.
Book | Missile type | Accel KPS^2 | Accel g | Power setting | Range | Seconds endurance | terminal velocity | details | quoted original text.

I probably don't have all of them; but at least through ART I think I have most of them -- at least the ones where useful information could be derived. (There were some where, for example, the text would only say their maximum range in the current situation -- but without the missile's acceleration numbers or the numbers for the speeds, vectors, and accelerations of the current situation the missile range is virtually useless)

munroburton wrote:

Relax wrote:Holy cow, man, you did what I keep telling myself to do as I read the books. Write down the numbers in an excel spread sheet. Big Kudos.

Don't mind me, I'll just steal your post and put it in my notes.

Why not just steal his spreadsheet outright? https://docs.google.com/spreadsheets/d/ ... sp=sharing

I check it sometimes when I come up with a half-baked idea... and then end up throwing out my drafted post entirely.

So yes, the RMN's countermissiles can do 130,000g for 60 seconds, generating a relatively simple 25% of C. You slap three of those drives together and you've got .75c achievable in 180 seconds. The Havenite MDM needs 540 seconds to do that!

Hah -- I'd totally forgotten I'd put together that cleaned up spreadsheet and made it available.

I keep going back to my local messy (but more detailed) one that I described in my post above

Speaking of typos and other errors I just noticed (possible not for the first time; though I don't remember bumping on it before) one in AAC.

When Truman was splitting up her BC(P)s as part of Grand Divide at Gaston we get the following

At All Costs - Ch. 20 wrote:"They're going to pincer us," Beach grunted. "About what I expected. Too bad they didn't just go ahead and send in the LACs as beaters."
"But look at this, Sir," Randall said, indicating the red arrows of projected vectors. "They may be going to try to open clear lines of sight to us, but on their current headings, the range will be less than seven million klicks."
"So they are a little nervous about Eridani violations," Beach observed, and smiled humorlessly. "On the other hand, our ships' best powered envelope from rest is under two million. Not a huge improvement."

Um - 7 million km is barely outside pre-war SDM range (180s @ 46,000 gees is 6,747,300 km from rest) so what the hell is that under 2 million from rest!?!

Okay, if they were dumb enough to fire them in high-speed mode then sure, 60s @ 92,000 gees is only 1,499,400 km; but that's not the range anybody sane would be quoting.

For that matter, that 7 million km should be within range of the RHN's current SDM. After all the ones their SD's carried at Elric (just before Buttercup) has right around 180s @ 44,750 gees giving 7,104,510 km range from rest.[1]

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[1]Okay it took some effort to work that accel number out. We were actually given:
range: 6.5 million km
closing velocity: 320 KPS
flight time: 172s
terminal velocity: "just over 75,700 KPS"

But base velocity, terminal velocity, and flight time is enough to figure out roughly what the missile accel must be. And the GSN SD(P)'s acceleration of 5 KPS^2 + 320 KPS base velocity will only shrink the range the missiles have to cover by 129,000 km in that 172 seconds; which is basically a rounding error in these numbers.
A sanity check of plugging in that base velocity, time, and my best fit (rounded off) accel of 44,750 gees in gives us a calculated terminal velocity of 75,751 KPS at a range of 6,542,072 km for that same engagement (which at least shows I didn't catastrophically mess up the basic math). So pretty darned close. 44,720 gees would give exactly 75,700 KPS but a) that's not "just over" and b) even rounding off to the nearest 50 is more precise that we've seen in actually quoted accel which have all been to the closest 500.

I've button punched the Cataphract numbers multiple ways and nothing works. PS: 2nd stage is 60s you have labeled as 75s.

We are told 70,100G with a range of 19.3Mkm... Doesn't compute as 180s@70,100G and 60s@98000G gets 20Mkm Yes, I am using 9.81 multiplier and not 10.

We are told 84,000G with a range of -32Mkm... Doesn't compute. I can get ~30Mkm, using 60s second stage, but trying to get around 31.5Mkm is near impossible unless you assume a drive time of 215s which is mighty odd as DW seems to like even integers of 30s or 60s and 215 is obviously 35s and if one goes with 210s, then we achieve 30Mkm which is FAR from 32Mkm as stated from rest. Yes, you can play with acceleration of 2nd stage but you have to assume a LOT higher acceleration. As in 160,000G higher...

Relax wrote:I've button punched the Cataphract numbers multiple ways and nothing works. PS: 2nd stage is 60s you have labeled as 75s.

I got that 75s directly from Duckk -- and since he has access to the tech bible...

Duckk wrote:Cataphracts go 467 KPS^2 for 180 seconds, then 961 for 75

viewtopic.php?f=1&t=6610&p=175299&hilit=+Cataphracts+go+467+#p175299
(Actually his post was directly in response to mine trying to make the numbers work with a 60s 2nd stage -- and getting the same ludicrous accelerations you were)

And of course given that that was a 2014 post we're talking only about the original Cataphracts. The exact conversion (rounded to the nearest integer) of those would be:
476 KPS^2 ~= 47,653 gees
961 KPS^2 ~= 98,061 gees

And his numbers give that original cataphract a continuous powered range of 16,572,713 km, and a terminal velocity of 156,135 KPS (0.52c)


But still, if the Malign and the Technodyne have a extended range CM drive, like the Mk31's (but slower) why haven't we seen any actual CMs built on it? A CM with those extra 15 seconds can add a million km of range to the 1.7 million that 60s @ 961 KPS^2 would give you.

(And secondarily why did the 2nd stage performance seem to stay the same even as later improved cataphracts made such massive improvements to 1st stage performance?)