In v3.0, I have added new point defence modes for missile fire control systems, allowing anti-missiles to be used in automated mode. The ten new modes are as follows:
One anti-missile per target missile
Two anti-missiles per target missile
Three anti-missiles per target missile
Four anti-missiles per target missile
Five anti-missiles per target missile
1v1 (Independent Target)
2v1 (Independent Target)
3v1 (Independent Target)
4v1 (Independent Target)
5v1 (Independent Target)
Each mode also has a max range set in the same way as for beam fire controls. A missile fire control assigned to one of the above modes will continue to launch anti-missiles at the closest incoming salvo until the number of anti-missiles in flight reaches the specified number. For example, take the Arleigh Burke class escort destroyer below. Assume its twelve launchers are split equally between its two fire control systems and both fire controls are set to ?Two anti-missiles per target missile? with a max range of 2.5m kilometers, which is the range of its missile detection sensor and its missile fire control systems.
Arleigh Burke class Destroyer Escort 6000 tons 515 Crew 1129.2 BP TCS 120 TH 480 EM 0
4000 km/s Armour 5-29 Shields 0-0 Sensors 1/0/0/0 Damage Control 0-0 PPV 12
Magazine 372 Replacement Parts 7
Congreve-Hale Ion Drive (8) Power 60 Efficiency 0.70 Signature 60 Armour 0 Exp 5%
Fuel Capacity 110,000 Litres Range 47.1 billion km (136 days at full power)
Point Defence Missile Launcher (12) Missile Size 1 Rate of Fire 10
SPG-3 Missile Fire Control (2) Range 2.5m km Resolution 1
Space Wolf (372) Speed: 24000 km/s End: 44.6 minutes Range: 64.3m km Warhead: 1 MR: 10 Size: 1
SQS-25 Missile Detection Sensor (1) GPS 252 Range 2.5m km Resolution 1
The destroyer detects an incoming salvo of ten missiles. Its fire control systems automatically lock on to the contact and check their orders. With ten incoming missiles and a setting of ?Two anti-missiles per target missile?, they can have a maximum of twenty anti-missiles in flight. None are in flight at the moment so they launch a total of twelve missiles. Ten seconds later the launchers reload and check to see if they should fire again. Twelve missiles are already in flight so they launch a further eight missiles between them, making twenty in total. Ten more seconds pass but the launchers do not fire any more anti-missiles because twenty are already on their way.
Lets assume that a minute passes and the first twelve missiles reach their target, destroying three of the ten incoming missiles. During the fire phase the two fire control systems re-assess the situation and determine that seven missiles are incoming, so with a setting of ?Two anti-missiles per target missile? they can have fourteen missiles in flight. As only the eight missiles of the second salvo are still in flight, they launch six more anti-missiles. Note that in the first five modes the two fire control systems are aware of what each other is doing and would also be aware of any other ships of the same Empire that are engaging the missiles. They follow their point defence orders based on the total missiles engaging the target, not just missiles under their own control. This means a fleet can engage incoming missiles automatically in a coordinated way without wasting anti-missiles. If a targeted salvo is destroyed and the fire control still has missiles in flight, those missiles will be redirected to the next available target.
The five modes that are listed starting with 1v1 (Independent Target) work the same way as above except for the important difference that a fire control with these settings will only engage a salvo that is not being engaged by any other fire control. This allows the defender to select different options depending on whether he is confronted by a few large salvos or many small salvos. In this case, each independent fire control will search for missile salvos that are not being engaged by any other fire control. Note that other fire controls may eventually target the same salvo as that currently targeted by an independent. In that case, the independent fire control will switch to an unengaged target salvo, if one is available. If not, it will continue firing at its existing target and will take account of missiles fired by other fire controls.
Below is a screenshot of an Arleigh Burke engaging an incoming salvo of forty-five missiles. There are actually two Arleigh Burkes defending the Tribal class destroyer Mayan but only one is firing in this example. Both missile fire controls on the Arleigh Burke are set to ?Two anti-missiles per target missile? with a max range of 2.5m km so they will keep up to ninety anti-missiles in flight. So far they have launched forty-eight defensive missiles. Throughout this example, the only action I have taken is to launch the Eastasian missiles and set the point defence modes on the destroyer fire control. All the action takes place automatically after that point.
Here we zoom in a little as the anti-missile start to engage. These are fairly primitive size 1 missiles with a 14% chance to intercept. The first 36 anti-missiles have destroyed 6 attacking missiles, leaving thirty-nine in the incoming salvo. The destroyer continues to launch more anti-missiles. This seems like an expensive defence but the anti-missiles only cost 0.65 BP each compared to 2.7 BP for each attacking missile and are only 1/4 the size as well. The cost ratio is still slightly in favour of the attacker but that will change with different types of attacking and defending missiles.
As the missiles are getting close and there are still seventeen left, the second Arleigh Burke joins in, with the two ships now firing a total of twenty-four defensive missiles every ten seconds. The reason they are shown as four salvos of six instead of the earlier 12 missile salvos is because I found a bug during the creation of this example
. The missiles were all being assigned to one fire control instead of being split between them.
Ten missiles from the original forty-five reach their target. The defenders launched 192 Space Wolf missiles to kill the 35 attacking missiles. Although they have a 58% chance to hit, only three attacking missiles strike Mayan's armour, with their six point warheads causing the following armour damage.
Steve