Newtonian Aurora

[shadenight123]

That's actually one of the main issues with realistic combat at relativistic speeds. One of the others is that due to the power, fuel and speed requirements, a "missile" is almost indistinguishable from a "ship".

"sir, we have developped the PERFECT DEFENSE!"
"what is it?!"
"we have moved ALL THE GARBAGE OF THE PLANET in a 360° sphere around ourselves! the ships cannot pass without auto destroying themselves!"
"you officer need a medal for this! free-pollution world and extremely effective shield? marvelous!"

[Antsan]

Unfortunately that wouldn't work because the garbage most likely won't stop the missile.  I guess it really doesn't matter if a destroyed or an intact missile hits you.

[Napoleon XIX]

I like the energy idea. However, have you thought of having heat brought into the game. Ie: needing to dissipate it via some means before the crew and fragile electronics boil away.

[Steve Walmsley (OP)]

I like the energy idea. However, have you thought of having heat brought into the game. Ie: needing to dissipate it via some means before the crew and fragile electronics boil away.

Yes I am looking at that. Just deciding whether it adds too much complexity . I will probably add solar panels as well as an alternative to reactors. They would work well for sensor buoys or ships deployed as pickets within an inner system. Very prone to damage though. Also contemplating something I read in Fire, Fusion and Steel (the New Era version) about a type of shield diverting absorbed energy into the ship's power grid. Lots of options at the moment.

Steve

[LoSboccacc]

if you fire MJs of energy out of a railgun, in a newtonian setting, won't that effect ship path and direction too?

[Rastaman]

Increase the muzzle velocity to 92,000 m/s and that 1 kg projectile has the destructive force of 1 ton of TNT. Even that is a relatively slow velocity in Aurora terms of 92 km/s. Unfortunately, that also requires a railgun with a muzzle energy of 4,232 MJ.
Interesting....

Steve

The picture is not fully correct I think. The TNT charge will affect all directions, the kinetic penetrator only one direction. So you need much more TNT to have the same effect on the target as the penetrator has.

[Steve Walmsley (OP)]

if you fire MJs of energy out of a railgun, in a newtonian setting, won't that effect ship path and direction too?

Yes, it would, although the effect would be tracked as Newtons not Joules. Momentum isn't the same as kinetic energy (and this is a weird one to get your head around) so increasing the velocity of a projectile by x5, would require 25x more energy and would give the projectile x25 impact but, at least as I understand the physics, would only give the projectile 5x more momentum and have 5x the effect on the launching ship in terms of affecting its movement. This is because the force applied to the ship is equal to the velocity x mass of the propellant (the railgun shot), not 1/2 mass x velocity^2, which is kinetic energy of the railgun shot.

However, I haven't decided whether to include it yet. Once I have some railguns designed I will run the math and see how much of an impact (unintended pun!) it has.

Steve

[Steve Walmsley (OP)]

The picture is not fully correct I think. The TNT charge will affect all directions, the kinetic penetrator only one direction. So you need much more TNT to have the same effect on the target as the penetrator has.

True - I am only using the comparison to hlighlight the energies involved. I have been looking at this site an an idea for possible use with nuclear weapons in Newtonian Aurora: http://www.5596.org/cgi-bin/nuke.php

The web site allows you to enter a weapon size, explosion distance and armour strength. It calculates how much of a nuclear weapon's energy will be applied againt each cm^2 and what how much armour would be destroyed.

Steve

[sloanjh]

if you fire MJs of energy out of a railgun, in a newtonian setting, won't that effect ship path and direction too?

As Steve said, it's the momentum that counts for the course change.  It would probably be wise to ignore this effect, unless Steve wants to track the mass of the railgun ammo.  The momentum of a projectile with mass M and kinetic energy K is sqrt(2*M*K), so for fixed K MJs of kinetic energy, the momentum goes to zero as the mass of the projectile goes down (and the muzzle velocity goes up).

A different way to say this is that keeping track of the momentum of the ammo treats the railgun as a reaction drive.  This is true, but the "real" drive is going to be MUCH more efficient, and so the effects of the railgun should be negligible.

John

[chrislocke2000]

wow, sounds like the wish list of features is comming on as well. looks like ship to ship combat is heading towards being slower and seriously closer to toe to toe. Question is are 5 second ticks going to be too long in these instances?

Also if you are revamping the weapons and energy systems any thoughts on separating laser generators from the turrets and just giving them an output power to divert to various turrets?

[PTTG]

Sounds like what we'll need is very fast lasers that vaporize incoming or stationary debris before it strikes the ship. If we extend that to weapons fire, we could say that making the projectiles out of different materials (much like armor) and making them faster would improve your combat effectiveness.

[Mel Vixen]

Steve regarding sensors and electromanetic weapons. If you fire a rail or gaus-/coil-gun you could a ship on the other side of the system see the spike in the EM?

Also thanks for thinking about alternative ways of energy production and storage. It would be nice if i could build a ship without any generator whatsover but with a bank of batteries.

What about "computer"-controlled ships? I mean like in ships without a actual crew but with a HAL like computer. Any opinions on that?

[Steve Walmsley (OP)]

I am going to start using this thread to post mechanics changes, even minor ones, for Newtonian Aurora so there is a reference when it is available to play

Starting with active sensors

Active Sensors now have a power requirement in MW equal to five times their sensor strength. For example, for a size 3 (150 ton) active sensor with sensor strength technology of 21, the power requirement would be 315 MW. For continuous operation of its active sensors, a ship is going to need power generation capability equal to their total power requirement. However, that power is actually going to come from the ship's integerated power grid (total homopolar generator capacity) rather than direct from the reactors (or other power generation systems TBD), so an active sensor that was intended for occasional use only could be mounted on a ship with sufficient power storage capacity to operate it, even if the power generation capability is insufficient for continuous use. Because of this extra hull space needed for sensors, I am going to increase sensor strength so you can have a smaller sensor with the same strength as before.

Having explained all that, I am probably going to gradually remove hull spaces (HS) from Newtonian Aurora and replace them with tons instead (on the existing 50-1 basis). For a game where mass is so important, I think having everything in tons rather than hull spaces will be much more intuitive. So by the time the game is available, sensor strength is likely to be per ton, rather than per HS.

Steve

[Steve Walmsley (OP)]

- Build ships with an FTL drive and magazines.
- Build tugs which are all-engine and fuel.
- Using the tugs, accelerate the FTL ships to 100 000 km/s into the direction of the enemy home star.
- You can do this at your leisure in a system under your control. The high entry speed will
propel your ship to the enemy in a couple of weeks maximum.
- Once in the enemy home system, jettison the missiles. Using Sol as an example,
the missiles need about 8.3 hours to reach Earth, with a maximum needed course correction delta-V of 5000 km/s
(1AU/3 billion km*100 000 = 5000).
5000km/s in 8 hours should be doable with antimatter drives, judging the ion engine missile examples and estimating
fuel and payload. Also 5000 is the maximum. You could time the attack in a way that you do not need much course correction at all.
- The FTL ships drive into the sun or are lost in space.

- The defenders now have a time window of 8 hours before the drive-by nuclear holocaust. That means only defensive assets on and around the target planet are able to intervene.

This may work if you have surveyed the target system first. Otherwise, it is unlikely the ship and its missile are going to be on a course that allows them to intercept the target. They may end up on the far side of the system, heading outwards without enough fuel to slow down. The other possible problem will be that as sensors will almost certainly be FTL (to avoid horrendous complications), the defenders will have some time to throw a rock in front of the missiles.

One thing I am considering (and the above scenario is pushing me more in that direction), is to have some new type of sensor that can detect an object based on its momentum (the disturbance of space-time or some other technobabble).

Steve

[Steve Walmsley (OP)]

Steve regarding sensors and electromanetic weapons. If you fire a rail or gaus-/coil-gun you could a ship on the other side of the system see the spike in the EM?

Also thanks for thinking about alternative ways of energy production and storage. It would be nice if i could build a ship without any generator whatsover but with a bank of batteries.

What about "computer"-controlled ships? I mean like in ships without a actual crew but with a HAL like computer. Any opinions on that?

Detection of an energy spike is something I am considering.

Depends what you mean by computer-controlled. 'Remotely piloted' would be simple enough as I would replace crew quarters with some type of 'quantum entanglement device' that allows instant control over interstellar distances. 'Computer controlled' in the sense that you can't tell the ship what to do, would effectively be the same as creating an NPR ship on your side.

Steve