How Overpowered Scifi Space Combat Would Be

[Bill Phil]

Just now, DDE said:

Define "better". Higher acceleration? Unlikely. Higher dV reserves? Perhaps, but are they high enough to both dodge missiles and carry out the original mission and get home? How high is that margin?

The problem is whether or not it’s possible to scale engines down to missile size. There may be a minimum size which limits the smallest possible vehicle size. And in some cases larger engines of the same type are more efficient.

[DDE]

1 minute ago, Bill Phil said:

The problem is whether or not it’s possible to scale engines down to missile size. There may be a minimum size which limits the smallest possible vehicle size. And in some cases larger engines of the same type are more efficient.

Yeah, but while we're stuck with chemical rocketry it's scaling up that is difficult.

[magnemoe]

8 minutes ago, DDE said:

Define "better". Higher acceleration? Unlikely. Higher dV reserves? Perhaps, but are they high enough to both dodge missiles and carry out the original mission and get home? How high is that margin?

For high end spaceship engines you can select: high trust/ high ISP / low mass and cheap ; select two. 
An spaceship would use something like an fusion engine or an nuclear pulse drive. This is not very practical for an missile as the engine weight 100 ton without fuel.  
Now you could solve this with either an missile buss, an unmanned disposable spaceship carrying an lot of shorter range missiles. 
The other option is an manned missile carrying ship, think an MTB in naval terms. Benefit here is that you don't have much light speed lag. You still want to keep your distance, 10.000 km start to get colose but the MTB is likely to have higher TWR especially after dropping most of its missiles. 

Now for missiles as said you are very visible while burning, you are pretty visible afterward, Now you could drop of payloads who are pretty stealthy  ( no stealth in space is true for thing under trust or having an life support, not for an bomb pulsed x-ray laser and some reaction wheels. 
Yes it need to expose its telescope but that only then getting into range. 

14 minutes ago, DDE said:

Yeah, but while we're stuck with chemical rocketry it's scaling up that is difficult.

True, however all the fusion design and the easy orion pulse nuclear works better if large. Fusion might well have upper limits but that will be huge 

[DDE]

19 minutes ago, magnemoe said:

True, however all the fusion design and the easy orion pulse nuclear works better if large. Fusion might well have upper limits but that will be huge 

Yeah, but fusion is either low-thrust or quite low-ISP. Orion is, yeah, but I still think it a somewhat improbable design choice.

[kerbiloid]

A really advanced civilization will detect the fleet and the missiles by absence of vacuum at that place, distorting the pattern of virtual particles birth.

When the arrea of distorted virtual particle distribution is linearly moving, sure it's somebody's phantom cruisers and cloaked torpedoes are approaching.

***

Chemical propellants have low density of stored energy and need simple equip.
Nuclear propellants are by orders of magnetudegreater energetical density, and need complex equip.

So, it's easier to build smaller chemical vehicle and bigger nuclear one.

[Terwin]

3 hours ago, Spacescifi said:

What? How?

Inerta won't let a vessel reverse course at 99% lightspeed, these are constant acceleration 1g engines.

You were referencing the 1LS minimum range to engage the FTL drive, just jump backwards 2-3 light seconds and over enough to try and hit again.  No need to change your inertia, just use your FTL to move back far enough for a second attempt to hit.

This 'missile' may not even have a proper STL engine as it was accelerated by dropping it towards a black hole, it just needs enough accuracy in its FTL to line up it's projected trajectory with that of the target.

[magnemoe]

1 hour ago, DDE said:

Yeah, but fusion is either low-thrust or quite low-ISP. Orion is, yeah, but I still think it a somewhat improbable design choice.

We don't have fusion, well we have some engine designs who need to be feed energy by an nuclear reactor or solar but his good isp. For obvious reasons fusion is an hot topic, it might be easier in space as you are in an vacuum chamber you don't need to keep filter out but its harder to get rid of waste heat. 
Orion the engineering look decent, building one is another issue. 

[Spacescifi]

1 hour ago, Terwin said:

You were referencing the 1LS minimum range to engage the FTL drive, just jump backwards 2-3 light seconds and over enough to try and hit again.  No need to change your inertia, just use your FTL to move back far enough for a second attempt to hit.

This 'missile' may not even have a proper STL engine as it was accelerated by dropping it towards a black hole, it just needs enough accuracy in its FTL to line up it's projected trajectory with that of the target.

 

Missiles don't jump, only ships are big enough to carry that equipment.

I guess you presume you can jump and then rapidly jump again once you hit yhe radius zone at 99% light speed.

It would not work, since you can only jump between DIFFERENT planets... sorry I forgot to mention that.

You cannot repeat jump the same planet without jumping to another you select.

Clever try though.

 

Edited July 23, 2020 by Spacescifi

[Terwin]

5 minutes ago, Spacescifi said:

Missiles don't jump, only ships are big enough to carry that equipment.

I guess you presume you can jump and then rapidly jump again once you hit yhe radius zone at 99% light speed.

It would not work, since you can only jump between DIFFERENT planets... sorry I forgot to mention that.

You cannot repeat jump the same planet without jumping to another you select.

Clever try though.

 

This collider was specifically large and with a jump drive(even if it had little else).

I'm sure you can afford to sacrifice a jump drive to take out a planet.

If it missed the target planet with it's first attempt, it can always pop-out to a different planet, then pop back to the target planet, if it still has the 60 minute jump drive cool-down, it might even jump to a different planet and then just travel at near C to the target again.

 

Using something with lots of energy to blow things up is easy, making something with lots of energy 'safe' is much harder.

[Spacescifi]

53 minutes ago, Terwin said:

This collider was specifically large and with a jump drive(even if it had little else).

I'm sure you can afford to sacrifice a jump drive to take out a planet.

If it missed the target planet with it's first attempt, it can always pop-out to a different planet, then pop back to the target planet, if it still has the 60 minute jump drive cool-down, it might even jump to a different planet and then just travel at near C to the target again.

 

Using something with lots of energy to blow things up is easy, making something with lots of energy 'safe' is much harder.

 

Nice try again.

Yet as I originally envisoned the this newer jump point drive... it still would not be easy to pull off.

 

Say you jump to a light second from Jupiter from Earth. Retaining your previous speed and trajectory of a near miss of Earth at lighhugger speed means you will leave jupiter's jump zone the second you appear.

Also, you appear at the edge of the lightsecond border NEAREST your vessel's position before you jump.

Which means that even if you jumped back to Earth's jump zone after a miss you would STILL be flying away from Earth.

At which point you are at the mercy of whatever STL engines you have to try to intercept a 1g or higher planet's lightsecond out jump zone border. Which would be... hard to say the least given the fantastic speed the vessel is already at. Far more likely to be headed straight out of the system with no way to get back for a long time... unless it somehow manages to snag a lightsecond jump zone of a 1g or higher planet years later in the next star system LOL.

No 60 second cool down waut required this time.

Enough wait time as it is just boosting at 1g to reach the jump zone border.

Wait time is for arbritrary suspense, which matters a lot less when vessels rely on jump points and constant acceleration.

Edited July 23, 2020 by Spacescifi

[Terwin]

24 minutes ago, Spacescifi said:

 

Nice try again.

Yet as I originally envisoned the this newer jump point drive... it still would not be easy to pull off.

 

Say you jump to a light second from Jupiter from Earth. Retaining your previous speed and trajectory of a near miss of Earth at lighhugger speed means you will leave jupiter's jump zone the second you appear.

Also, you appear at the edge of the lightsecond border NEAREST your vessel's position before you jump.

Which means that even if you jumped back to Earth's jump zone after a miss you would STILL be flying away from Earth.

This is still assuming a miss.

options to mitigate that change include:

A) double-check your math.  Planets and black-holes don't dodge, if you are careful, the odds of missing can be very low.

B) relativistic 'gravel' in a net that you release just after jumping into the system.  Even if each rock is a couple hundred kg, you only need a few at 99% of ls to take out a planetary biosphere(possibly just one)

C) plant a bomb in the middle of your asteroid and blow it up just after the jump into the system so that you have a large and growing cloud of relativistic debris heading towards your target.

D) walk your shots: have a hand-full of colliders start to accelerate one after the other, and if the first one misses, adjust the destination coordinates of the second and try again.(left-overs can jump to the far side of the black-hole to slow down for future use)

 

 

 

[Spacescifi]

50 minutes ago, Terwin said:

This is still assuming a miss.

options to mitigate that change include:

A) double-check your math.  Planets and black-holes don't dodge, if you are careful, the odds of missing can be very low.

B) relativistic 'gravel' in a net that you release just after jumping into the system.  Even if each rock is a couple hundred kg, you only need a few at 99% of ls to take out a planetary biosphere(possibly just one)

C) plant a bomb in the middle of your asteroid and blow it up just after the jump into the system so that you have a large and growing cloud of relativistic debris heading towards your target.

D) walk your shots: have a hand-full of colliders start to accelerate one after the other, and if the first one misses, adjust the destination coordinates of the second and try again.(left-overs can jump to the far side of the black-hole to slow down for future use)

 

 

 

 

Hmmm... maybe.

Two questions.

Time dilation: Won't time dilation effect the spacecraft, even if it is a massive black hole? Meaning any peace treaty will be null and void if the AI auto death spacecraft attacks years later LOL?

And I presume you only do stunts like this if the enemy is trying to annihilate your race from existence right?

Like... this is not the kind of stuff you pull over mere proxy wars over territorial disputes right? I hope not. That would be rather extreme and quickly put your empire in the 'evil empire' catergory to every known race.

Because if your plan works... let's just say someone somewhere will seek to pay back the favor... so unless there is an off world or other colony world, this seems really risky.

Just because you devastate a world does NOT mean all their space assets are gone too.

 

 

 

Edited July 23, 2020 by Spacescifi

[Terwin]

1 hour ago, Spacescifi said:

Time dilation: Won't time dilation effect the spacecraft, even if it is a massive black hole? Meaning any peace treaty will be null and void if the AI auto death spacecraft attacks years later LOL?

You can calculate this before hand.

I was not expecting AI, just a pre-planned program that follows certain steps at the appropriate(subjective) time.

1 hour ago, Spacescifi said:

And I presume you only do stunts like this if the enemy is trying to annihilate your race from existence right?

Like... this is not the kind of stuff you pull over mere proxy wars over territorial disputes right? I hope not. That would be rather extreme and quickly put your empire in the 'evil empire' catergory to every known race.

Because if your plan works... let's just say someone somewhere will seek to pay back the favor... so unless there is an off world or other colony world, this seems really risky.

Just because you devastate a world does NOT mean all their space assets are gone too.

That is politics, I am just addressing technical challenges.

[Spacescifi]

1 hour ago, Terwin said:

You can calculate this before hand.

I was not expecting AI, just a pre-planned program that follows certain steps at the appropriate(subjective) time.

That is politics, I am just addressing technical challenges.

 

I see... technically there are counter measures.

1. Search out and blockade with lethal force any black hole you find like your world's life depends on it, because it DOES.

2. Build massive antimatter shotgun particle beam orbital stations that can wipe out a large asteroid into space dust... doing much the same to anything coming from the precalculated direction of known black holes.

3. Granted spaceships could manage a sneak attack. Which is why ALL vessels can only jump in from like... saturn and then take weeks to get here at 1g.  Otherwise orbital battle stations will shoot on sight.

Yes... a civilization would have to be either paranoid or experienced in war disasters or paranoid to do such.

Edited July 24, 2020 by Spacescifi

[kerbiloid]

8 hours ago, Terwin said:

No need to change your inertia, just use your FTL to move back far enough for a second attempt to hit.

If make the ship out of cast iron, finally you can drill a hole in their planet.