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[Elysia] Adrast-Type Tactical Missile Update

F

FrostJaeger

Banned Member
  • Submission Type: Article Update
  • Submission URL: Linky
  • Original Article URL: Linky
  • Contains Unapproved Sub-Articles? Nope.
  • Contains Links to Unapproved Articles? Yep.
  • Contains New Art? Nope.
  • Previously Submitted? Nope.
  • Changelog: Linky
An update for an older torpedo missile design that unfortunately never saw the light of day due to its host platform never being completed.

This article will be receiving art at some point in the future, however, it's currently a low-priority item because of its age and lack of usage.
 
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You do know it takes a Mach 3 missile to intercept a Mach 1 target right?

If you want a good example of reasonable speeds look at the ratio of submarine speeds to the speeds of torpedoes intended to kill them.
 
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Why, specifically, does it take a Mach 3 missile to intercept a Mach 1 target? The reason why might be relevant to these discussions or it might not. I need a bit more detail before I can determine if your point is valid. As things are, a missile moving just 0.025c faster than a vessel can gain 7494.8 km on its target per second. That's a difference of over half the diameter of an Earth-like planet. If my math is in error, feel free to correct.

At the ranges we employ for combat, the Captain might have JUST enough time to order the ship to respond against a missile with a 0.025c - 0.1c speed advantage...which seems just right to me.
 
But we aren't just dealing with those kinds of ranges. If you're driving, say, a Plumeria that close, you're risking a lot engaging in that range.

It's probably much smarter to engage within 0.5c. In which case, your 0.025c advantage missile will intercept in 20 seconds.

20 seconds response time seems like a bit much. In 20 seconds, the MEGAMI has enough time to fiddle with the conditions, rearrange shields, carefully aim point defense, get the CO's coffee brewing, and summon her own avatar to open the mini-fridge in the bridge and hand an emergency snack to the XO. And then shoot the missile.

Small edits: If you think 0.5c is too far, I beg to differ. The current generation of Mindy has an STL movespeed of 0.38c. The Hostile has a speed of 0.365c. And the Tethys has a speed of 0.375c.

If anything, 0.5c range is too low, isn't it? But 0.5c is 1.5x10^8 meters, or approx 150,000 km.
 
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While concievably correct, there are assumptions being made. First, you're assuming that the warship is already moving at full speed directly away from the missile when it's being launched for that 0.025c difference. Profoundly unlikely. The Plumeria is likely to be facing its target or maneuvering rather than running pre-launch at full speed. Secondly, 0.025c assumes that the missile and the targeted ship are made of the same materials. This is unlikely, since ships have armor and missiles aren't likely to be weighed down. That Plumeria also has heavy armor, meaning an unshielded missile has a speed difference of 0.075c, cutting that "ideal" time to 6 and 2/3rds seconds. 20 seconds is a best case scenario in the given conditions, by no means the common case.
 
To counteract your idea that the warship is already moving directly away, making calculations invalid, remember that all missiles need time to accelerate to top speed, which adds on time.

During our calculations, we were both using ideal missiles -- sort of a term I'll be coining on-the-spot for a missile that can accelerate from 0% to 100% in an instant, can't be shot down by power armors running interception duty, and on top of that assuming the MEGAMI isn't actively maintaining point defense work.

Besides, we don't care about the missile and ship being made out of differing materials. It doesn't make sense to measure the speed of a missile, then put armor on it which slows down its top speed. No, we put armor on the ship and missile first, and then measure speed.

And again, 0.5c engagement range is a very short engagement range. A current production Mindy can cross that gap in a hop, skip, and teleport-fueled jump. In fact, most power armors can cross that gap in almost no time at all.

20s is a best case scenario. Most of the time, it should be a little higher.
 
We do care about the missile and ship being made of differing materials. It influences the missile's top speed and the ship's top speed under the recommended table. A Plumeria's top speed is 0.375c, and a missile that has no shielding has a top speed of 0.450c. That multiplies the speed difference by a factor of three to 0.075c, hence my earlier 6 2/3rd seconds possibility. Also, if you want to take acceleration into account, a ship in combat will use CFS for barriers and its TAP Engines for STL...which have a notably lower acceleration than this missile's CDD by Wes' own account.

We're also ignoring the fact that these missiles are small enough to fire in groups. All those things make them more viable than presented. Not impossible to evade/react to, but a threat.
 
If we want @Wes in this, he has said in Discord that a ship's large thrusters should get a ship up to speed faster than a missile's small thrusters.
Additionally, groups or no missiles are not a problem. A Type 31 Anti-Fighter Turret as confirmed by Wes (again, on Discord) states that it should be firing around 700 shots/minute, or a little over 8/s. I'm not sure if it was per barrel, making it 32 shots/s, or in total, making it 8/s.

6.66s is a fair amount of time as well. That's still enough time for a MEGAMI or a generally competent point defense operator to lock onto incoming targets to shoot them down.

And what if a ship uses a mixture of CFS propulsion and TAP STL? Wouldn't a ship have a far higher acceleration then?

And again, 0.5c engagement is a tiny, tiny range. It's much more likely a captain would instruct his or her crew to fight at 1c~1.5c range -- 300,000km.
 
We're not arguing for an impossible to avoid missile here, or even a primary weapon-grade threat. And if a captain wanted to do that, yes, they could.

As for such combat ranges...I don't know what's common today, but back when I did combat RP, we very rarely had such large ranges for combat in play. Even half a light-second was pretty big (I assume that's what you mean by 0.5c), especially when fighting over territory like a planet. Also...missiles traditionally get up to speed faster than a target vessel by virtue of being light and having a one use engine that can be pushed harder given its size class...
 
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My two cents on the issue of missile/torpedo acceleration, regardless of who's arguing for what, is that generally missiles ought to (at least in my mind) get up to speed faster because they
  • Are lighter and have a better thrust to mass ratio (assuming that most of the missile/torpedo is dedicated to engine) and
  • Don't have to worry about squishy people going splat from too much acceleration
 
My thoughts about missile speed versus ship speed:

A ship's engines are larger and more powerful, however the starship itself in almost every case will be SIGNIFICANTLY heavier than a missile.

With regards to construction materials and speed: the speed assigned to a missile/starship is likely assigned BEFORE the materials. The person making a missile or starship likely will make a "stat list" of sorts which would be the base stats-damage, range, et cetera. However, a top speed can be adjusted by, say, a different propulsion system in the missile-I doubt we only have one missile propulsion system in the SARP universe, and I also doubt any available systems can't in one way or another be adjusted in production and development.

...Then again this is space and top speed shouldn't technically exist anyways. There is no top speed in space, because the speed of light is in itself completely relative. Acceleration would logically be the stat that replaces top speed... But this paragraph is off topic.
 
I'm a huge fan of using acceleration instead of top speed, but yeah, it's also off topic...
 
Exactly, we shouldn't argue for an impossible-to-dodge missile. Except in our case, "dodging" really means "kiting the missile for enough time so that the PD turrets shoot it down."

It's also a big mistake to assume both sides in a conflict are, relative to each other, stationary. Given that ships in combat will dodge just about anywhere and everywhere due to CFS omnidirectional movement, missiles will have to make tight turns in order to hit their target, again giving an extra amount of buffer time.
 
I just realized that we still have FTL-capable missiles of similar length (Ke-Z1) that can go at 12c and are still commonly used in the setting, so giving missiles a higher STL speed might actually be a moot point if these were given an FTL mode. Unless the submitter does not want to do so. However, if he wants to make what is explicitly called a "Long-Range Variable-Purpose Missile", it has to be able to function in line with its contemporaries.

The torpedo just has to drop out of FTL before their attack (mandated explicitly for Ke-Z1), which gives the captain that hurried chance to respond.
 
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The other stipulation for FTl use is that FTL does not work within about an hour travel time of planets.

Meaning there is an area of FTL safety around a planet that can buffer against these kinds of weapons.
 

Although @Wes would have to clarify on this, I'm 99.99% sure that faster-than-light weapons - including missiles - are no longer permitted within the setting due to shenanigans such as the Battle of Artume.

Zack said:
The other stipulation for FTl use is that FTL does not work within about an hour travel time of planets.

Meaning there is an area of FTL safety around a planet that can buffer against these kinds of weapons.
Click to expand...

False, @Zack. If memory serves (again, @Wes would have to clarify on this) faster-than-light travel is impossible within a star's Hill sphere.
 
Okay, that is an acceptable answer, especially for something that is meant for use on a defense platform in a star system. The Ke-Z1 might need adjusted to reflect this change.

Maybe high STL speeds are necessary for missiles given all these things...as long as the explanation is that the propulsion systems are one-use and can thus be overtaxed. And as long as it is approved as an amendment to DRv3.
 
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How's this going now that you've got an answer to Wes and had some time to talk it out with everyone, @FrostJaeger?
 
A second thought, mind creating another thread for the station article so that we can approve that if it's ready and then do the same for the heavy torpedo that's been sitting awhile?
 
No problem. Have fun, duderino. I'll make sure to not let it get rejected for rot while you're gone.
 
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