Another update - this time on FTL Drive design. FTL Drives replace Jump Drives in Newtonian Aurora. In the create research project window, they have five design parameters:
FTL Drive Efficiency: This serves the same function as jump drive efficiency, except it starts at efficiency 4 rather than 3 and each level is half the cost in research terms. For example, efficiency 6 is 8000 RP instead of 15,000 RP. In Newtonian Aurora you won't be able to use a gate to get between systems so non-FTL-capable ships can only be moved between systems via squadron jump or in hangar bays. Therefore FTL drives will be a lot more common than jump drives.
Max FTL Squadron Size: The same as standard Aurora, except that squadrons will travel through hyperspace together rather than through jump point. There will only be squadron jumps as there are no jump points to hold open. Creating drives that can jump multiple ships is easier though as the base drive can handle four ships and the research costs are half as much as before.
Hyperspace Dimension: The hyperspace dimension through which the ship or squadron will travel. Higher dimensions bring real space locations closer together and increase effective speed. Each dimension is rated for the speed multiplier it provides. The Alpha Dimension is 500x speed, the Beta Dimension is 1000x, Gamma is 1500x, etc.
Base Size: The base size of the FTL drive. This is comparable to the size of a military jump drive in standard Aurora, although there is no distinction between military and commercial drives in Newtonian Aurora.
FTL Size vs Stealth: It is possible to increase the base size of the drive without affecting cost or crew requirements, in order to create drives for much larger ships such as freighters. This has a penalty though. Each of the size modifiers has an effect in sensor blindness and drive flare. The x1 size modifier is the normal drive, causing no blindness and resulting in no drive flare. The 1.5x size modifier causes 15 minutes of sensor blindness and causes a drive flare equal to the arrival speed. Drive flares can be detected by EM sensors. The 2x size modifier causes 30 minutes of sensor blindness and causes a drive flare equal to double the arrival speed, et cetera. The size modifiers go up to size x10, which has 32 hours of sensor blindness and a drive flare equal to 10x speed, which is obviously not a good idea if you want to arrive unseen or detect anything else. However, it is probably fine for a freighter or colony ship travelling in known space.
Example: Here is a military-style drive intended for a ship of 6000 tons. This uses the efficiency 8 (15k RP), the Delta hyperspace dimension (8000 RP) level and the base squadron size (2000 RP)
Combat FTL Drive
Max Ship Size: 120 (6000 tons) Max Squadron Size: 4 Speed Multiplier: 2000
Jump Engine Size: 15 HS Efficiency: 8 Jump Engine HTK: 3
Sensor Blindness: None Drive Flare: None
Cost: 56 Crew: 75
Materials Required: 11.2x Duranium 44.8x Sorium
Development Cost for Project: 560RP
Here is exactly the same drive but with the max size modifier
Commercial-style FTL Drive
Max Ship Size: 1200 (60000 tons) Max Squadron Size: 4 Speed Multiplier: 2000
Jump Engine Size: 150 HS Efficiency: 8 Jump Engine HTK: 3
Sensor Blindness: 32 hours Drive Flare: 10 x Arrival Speed
Cost: 56 Crew: 75
Materials Required: 11.2x Duranium 44.8x Sorium
Development Cost for Project: 560RP
FTL Travel
Travel between different star systems is only possible using an FTL drive (although you never know - sub-light generation ships might make an appearance at some point). Stars have a hyper limit, inside which it is not possible to activate an FTL drive. This limit is equal to primary star mass squared, multiplied by three billion kilometers. For Sol, this is about the orbit of Uranus. In order to reach another star system, the FTL-capable ship or fleet has to align ltself with the destination system. This can be done using the new "FTL Align and Jump" order. Until the ship is on an exact course for the destination it will be unable to jump. Aurora will automatically make course corrections (using any available DeltaV) in order to align while this order is in effect. You will also be able to optionally specify a minimum jump speed so the ship will not enter FTL until it reaches the desired speed.
At this point, you wil lose contact with the ship and be unable to communicate until it reaches its destination system, which may be a period of weeks or months. If a full gravitational survey of the destination has been carried out, the ship will arrive with approximately the same speed at which it entered hyperspace, on a bearing from the primary within six degrees of the direct course from the start system and at a range from the primary between 100% and 110% of the hyper limit radius. If the destination system has not been surveyed at all, the location of arrival could be anywhere in a toroid, between 100% and 170% of the hyper limit distance, on any bearing from the star. The heading of the ship will still be directly away from the start system so you could end up on a course perpendicular to your destination, or even beyond it and heading away. A partial survey of the destination will result in a scenario somewhere between the two extremes. A lack of survey information could also result in the ship arriving slower or faster than expected, although within 30% of departure speed, and correspondingly earlier or later than expected. Because the ship is out of contact, you will be unable to determine the likely arrival point ahead of its arrival.
This uncertainty will make assaults on unsurveyed systems 'interesting' to manage. As well as the obvious issue of coordinating multiple squadrons, it will be a lot harder to pull out of an assault if things are not going well. To return to their starting system, ships will have to slow to zero and then begin accelerating along a reciprocal course. Another option may be to escape to another system that is on an easier escape course, fuel permitting. One other result of the above is that there will be far more 'spreading out' of civilian traffic rather than the current situation where ships tend to travel in large groups.
The speed at which interstellar travel takes places is equal to the speed at which you enter hyperspace multiplied by the speed multiplier of the FTL Drive. For example, if a ship using the drive shown above entered hyper at 8000 km/s, its effective speed would be 8000x2000 km/s, which is about 53x light speed. A journey to Alpha Centauri would therefore take about a month and a journey of ten light years would require about 10 weeks. Ships cannot accelerate or decelerate within hyperspace so the decision is whether to expend fuel and time to reach a high speed before entering hyperspace, or to enter at lower speed, saving fuel but extending journey time.
Steve
