I've been thinking a bit about the in-universe logic of the FSD. It seems to me that, with the correct modifications, the frame shift drive could be used to catapult a ship at relativistic speeds in an arbitrary direction when it exits slipstream. This is based on several observations:
(For this description, I'm making several assuptions about the FSD process. First, that all the acceleration takes place before the ship exits FSD. Second, that there isn't any way to identify ships with large relative velocities until they leave slipstream)
The ship exits slipstream at 0.9c at a distance of 15 kilometers.
The station will know about the ship in 50 microseconds.
It will impact the station in 56 microseconds.
The station has 6 microseconds to react before it is obliterated.
The ship will impact the station before the light from its arrival has reached the far side of the station.
A sidewinder going at 0.9c has as much energy as a bomb with a 1300 gigaton yield.
That all sounds awesome, but sidewinders don't carry enough fuel energy to achieve that kind of speed without some major thermodynamics violations (or other, less exotic means like in-flight refueling)
The fastest a sidewinder could ever go is 0.07c. Let's revise the previous series of events.
The ship exits slipstream at 0.07c at a distance of 15 kilometers.
The station still knows about the ship in 50 microseconds.
This time the ship will impact the station in 714 microseconds.
Now they have 664 microseconds (over half a millisecond to respond)
There's still nothing they can do. Even if they could totally vaporize the sidewinder, the leftover vapor of the ship would still render the station into tiny pieces.
At 0.07c (or 21,000 kilometers per second), the sidewinder still represents 2.7 gigatons of TNT worth of kinetic energy.
2.7 gigatons is the upper limit on a sidewinder loaded with fuel tanks. While the experimental yield of such an attack will probably be less energetic, remember that there are more than a few methods to refuel from slipstream in Elite, so more energetic rams are entirely possible. At any rate, the more important aspect of an FSD assisted relativistic ram is that there isn't any realistic way to defend against it. Defenders would have to successfully interdict every single ship that tries to approach the station. If they let a single ship through, the station gets obliterated.
Not only that, even if the station has a team of round the clock defenders interdicting every approaching ship, the attacker could simply exit slipstream early. In the case of the first ship, they could drop out at a distance of 10ls and they would still arrive only second after their light.
In the case of the second ship, consider that all you need to pull off this attack is a sidewinder, some fuel tanks, and a software patch to remote control your FSD for the attack. A reasonably well off individual could deploy quite a few ships for a simultaneous attack. A small government could field thousands. This is like using a Volkswagen Beetle and a full tank of gas to destroy a small city.
Have fun thinking about what else you could use an FSD for.
- Ships always exit slipstream at rest with the target object.
- This capability appears to function regardless of how fast the target object is traveling. (for reference: the fastest moving star detected in the milky way is traveling at 0.08c)
- A ship traveling between Mercury and Venus at opposition would need to spend 23 minutes experiencing 6G of acceleration to match velocities.
- Ships can travel between Mercury and Venus at opposition in less than 23 minutes using the FSD.
- Therefore, the FSD can change the velocity of the craft in real space without affecting the pilot physically. (This is kind of to be expected of any device which warps spacetime to move around.)
- This velocity change uses a negligible amount of fuel. (At least for these velocities)
- Thus, with enough fuel, the FSD can be used to accelerate ships to significant percentages of c.
(For this description, I'm making several assuptions about the FSD process. First, that all the acceleration takes place before the ship exits FSD. Second, that there isn't any way to identify ships with large relative velocities until they leave slipstream)
The ship exits slipstream at 0.9c at a distance of 15 kilometers.
The station will know about the ship in 50 microseconds.
It will impact the station in 56 microseconds.
The station has 6 microseconds to react before it is obliterated.
The ship will impact the station before the light from its arrival has reached the far side of the station.
A sidewinder going at 0.9c has as much energy as a bomb with a 1300 gigaton yield.
That all sounds awesome, but sidewinders don't carry enough fuel energy to achieve that kind of speed without some major thermodynamics violations (or other, less exotic means like in-flight refueling)
The fastest a sidewinder could ever go is 0.07c. Let's revise the previous series of events.
The ship exits slipstream at 0.07c at a distance of 15 kilometers.
The station still knows about the ship in 50 microseconds.
This time the ship will impact the station in 714 microseconds.
Now they have 664 microseconds (over half a millisecond to respond)
There's still nothing they can do. Even if they could totally vaporize the sidewinder, the leftover vapor of the ship would still render the station into tiny pieces.
At 0.07c (or 21,000 kilometers per second), the sidewinder still represents 2.7 gigatons of TNT worth of kinetic energy.
2.7 gigatons is the upper limit on a sidewinder loaded with fuel tanks. While the experimental yield of such an attack will probably be less energetic, remember that there are more than a few methods to refuel from slipstream in Elite, so more energetic rams are entirely possible. At any rate, the more important aspect of an FSD assisted relativistic ram is that there isn't any realistic way to defend against it. Defenders would have to successfully interdict every single ship that tries to approach the station. If they let a single ship through, the station gets obliterated.
Not only that, even if the station has a team of round the clock defenders interdicting every approaching ship, the attacker could simply exit slipstream early. In the case of the first ship, they could drop out at a distance of 10ls and they would still arrive only second after their light.
In the case of the second ship, consider that all you need to pull off this attack is a sidewinder, some fuel tanks, and a software patch to remote control your FSD for the attack. A reasonably well off individual could deploy quite a few ships for a simultaneous attack. A small government could field thousands. This is like using a Volkswagen Beetle and a full tank of gas to destroy a small city.
Have fun thinking about what else you could use an FSD for.