Bit of background: you may know me for my PVP and flight instructional videos. I’m passionate about space combat and that’s what I dedicate myself to in this game. I share a discord community called Lykosar’s PVP academy which is 700 members strong and growing, and I’m a leader of Liberty’s Reapers, one of the two largest and most active PVP-focused orgs. While I’m a physician rather than a physicist by trade, I have a solid understanding of classical mechanics which largely governs space flight in 6DOF simulators like Star Citizen. With thousands of hours spent dogfighting other players and analyzing how we fly in response to the flight model and combat balance, and knowing CIG has an upcoming combat summit to discuss the flight model, I wanted to make this post. The points I want to cover: - How dogfights would look like based on how ships currently perform (accelerate) if we had a truly realistic flight model, AKA with no speed limits as would be the case in reality. -How dogfights play out currently. -How the flight model can be adjusted to simulate realistic space combat more accurately. Let’s ignore the limitations of a game engine in supporting uncapped speeds and imagine what space combat would really look like just based on the present tuning of ship accelerations. While the fastest ship can only reach a maximum speed of about 1500 m/s in Star Citizen, my research into the subject of speeds in space revealed that we should be able to comfortably reach at least 1/10 of the speed of light before “space dust” or micrometeorites become a significant problem. 1/10 of the speed of light is 30 million m/s. What that means is that our ships in combat would never really have to think about hitting an absolute speed limit, and only speed relative to the ships you’re fighting would be relevant. The impact of this is significant. This means that a ship with greater acceleration will always be able to catch up to and overtake a ship with lower acceleration in open space. A Carrack flying away at full burn can produce 3.5 gs of forward acceleration while a Gladius pursuing it can produce 9.1 gs of forward acceleration. Even if the Carrack has a lead of thousands of kilometers and with a head start speed of 100,000 m/s, the Gladius, due to its higher acceleration, will steadily drop that closing speed, overtake the speed of the Carrack, and eventually catch up to it. In the current game, this does not play out, as both the Gladius and the Carrack have a max speed of 1236 m/s. This means that the Gladius will never be able to catch up to the Carrack in a straight line, because once both hit 1236 m/s, the distance between them will remain constant and cannot possibly be overcome. The Carrack expedition is more egregious, because even though it has far less acceleration than a Gladius, it has a top speed around ~1500 m/s which doesn’t really make sense. Generally speaking in an atmosphere, motorcycles will have higher accelerations at low speeds than cars but cars will reach higher top speeds because their engines can overcome the greater air resistance at higher speeds. In a vacuum, there is no air resistance, so acceleration is the only variable that determines whether one ship can catch up to another. In dogfights, I see a similar scenario play out constantly. If I’m in a Gladius fighting another Gladius, a tactic a losing player will often take is to fly in reverse and hit the top speed. That means the pursuing Gladius cannot overtake them, position behind them, or do much of anything and instead is forced to fly in a straight line while taking fire from the backstrafing Gladius. In a realistic scenario with uncapped speeds, as soon as the kiting Gladius turns around to face the pursuer, they will only have 6.1 gs of escape acceleration via their backwards thrusters. This would mean that the pursuing Gladius, with 9.1 gs of forward acceleration, would eventually catch up to and overtake them. Now let’s go back to Star Citizen. The game engine cannot support a truly realistic flight model because we must deal with speed limits. In fact, the higher the speeds get, the more severe desync becomes so we don’t want combat to be happening at high speeds. So how can we make the flight model more realistic but still support speed limits? My solution is to have top speed in any given direction proportional to a ship’s acceleration in that direction. On the left is the current FM. The ring represents top speed in any direction. The arrows depict the ship’s possible acceleration vectors. The right is my proposed flight model, with the box representing top speed in any direction. As you can see, in my FM top speed is a function of acceleration. However much acceleration a ship can produce in a given direction, its top speed in that direction is a constant multiplied by that acceleration. I chose that constant to be 136 which is arbitrary and obtained by dividing the current speed limit of the Gladius by its forward acceleration. 136 times 9.1 gives us 1236. 136 times 4.4 gives us 599, and so on. Applying boost, which doubles your acceleration, will not have an effect on top speed. What happens if you exceed the speed limit? An example of this would be if a Gladius is flying forward at 1236 m/s and then turns its nose 180 degrees to face backwards. Its speed limit is now 829 from the 1236 it was before it started the maneuver. This is up for debate, but I think fighters should decelerate more quickly than large ships (otherwise large ships can use the deceleration as an evasive maneuver). My proposed deceleration value is obtained by first taking the average acceleration capability of that ship, calculated by the sum of the forward, reverse, vertical strafe, and horizontal strafe values, dividing that by 4, and taking the square root of that number. For the gladius, its average acceleration is 5.4, and the square root of that is 2.3. So when the Gladius is flying at 1236 m/s and then does an about face, without any thruster input, it will decelerate at 2.3 g until it reaches 829 m/s. This deceleration will not use fuel and not activate any thrusters. However, if the pilot wants to purposefully turn and burn, they can apply thrust and will accelerate up to 9.1 g. The passive deceleration will not add to the thrust acceleration. This would fix a few other unusual scenarios. In planning org training missions involving a team of fighters/bombers attacking a capital ship with escorts, we realized the battle would devolve into the capital ship flying away at max speed, the attacking ships chasing it at full speed, and the defending fighters chasing them. The only solution was to force the capital ship to fly intentionally slowly so the battle can circulate around it. We also had to force the capital ship to not just QT away which it could do, but that’s another discussion. Regardless of how ship accelerations end up being tuned, having top speed proportional to acceleration will ensure ship encounters in SC play out more similarly to how they would in reality.