Newtonian Space movement

[Fallon Kell]

Some new rules for simplified Newtonian movement covering space combat and a few atmospheric movement rules. I've been threatening to release... I'd like your thoughts, suggestions, and other input. Questions are also welcome, especially since I haven't quite figured out a clear way to describe some of the concepts here...

Newtonian Space Movement:

Ships:

The "Space" rating of a starship is both the maximum speed a ship can travel at and still maintain full control, and the rate at which it accelerates. A ship can accelerate or decelerate by its space rating in a single turn, adding or subtracting its acceleration to its speed from the previous round. A ship's speed is limited only by the time it spends accelerating.

For example, a standard Corellian Stardrives CR90 Corvette, has a space rating of 6. Travelling full speed ahead, a CR90 can move 6 space units in one turn, a total of 18 units in two turns, and a total of 36 units in three turns. In the given rounds the speed of the ship is as follows: Round 1 - 6 space units per turn, Round 2 - 12 space units per turn, round 3 - 18 space units per turn. Deceleration is likewise. If the CR90 chooses to slow to a stop after three turns, it will take 3 turns to come to a full stop, with a total distance traveled while decelerating of 18 space units.

A difficulty level is added to all maneuvers for each additional turn a ship spends accelerating. An X-wing, with a space rating of 8, that has been accelerating for two turns will be travelling at 16 space units per turn. Any maneuvers the pilot attempts will be one level more difficult. If the X-wing is travelling at 24 space units per turn, any maneuver will be two levels more difficult, and so on. Reducing speed for a maneuver reduces the difficulty one level.

In an atmosphere, a ship's space rating becomes an absolute speed. A space rating of 1 equals a speed level of 100 meters per second, 2 equals 200 meters per second, and so on. A spacecraft in an atmosphere cannot accelerate past its speed rating, but it can enter an atmosphere moving faster than its speed limit. It will slow to its speed limit at a rate of one speed level per turn, or two levels per turn if the pilot brakes. An unshielded ship travelling faster than one speed level takes 1D damage per level each turn, due to surface heating. A ship travelling above one speed level may use aerodynamics to make maneuvers at normal difficulty, but the hull takes 1D damage per speed level above one due to G loading. If the pilot wishes, the maneuver can also be made at the increased difficulty to avoid the maneuvering damage.

Projectiles:

Weapons such as proton torpedoes and concussion missiles are also carried forward by inertia. They generally have short thrust phases in which they can accelerate and maneuver, followed by a ballistic and unguided phase. Each warhead has an acceleration rating and a thrust phase rating. When a warhead is fired, it moves forward at its original launch velocity plus it's acceleration rating, and continues to accelerate for the duration of its thrust phase. After it runs out of thrust, it continues in its original direction at its highest speed.

For example, a concussion missile may have an acceleration rating of 15 and a thrust phase of 2 rounds. If it is fired from a ship moving steadily forward at 10 space units per turn, it will have a speed of 25 in the first turn and 40 in the second. After it runs out of thrust, it will continue at a speed of 40 space units per second. At the end of the thrust phase, the warhead will have outpaced the craft that fired it by 45 space units.

For each turn a projectile is unpowered, the target gets +1D to evade. Furthermore, the initial difficulty to hit with an unpowered projectile increases by 1 level per turn of unpowered flight time required to reach the target. A starfighter scale craft may that makes a full evasion while a projectile is in unpowered flight cannot be hit by that projectile.

_________________
Or that excessively long "Noooooooooo" was the Whining Side of the Force leaving him. - Dustflier

Complete Starship Construction System

[Ankhanu]

[Fallon Kell]

[Ankhanu]

[Fallon Kell]

[Bren]

If you are tracking locations, then once the evading ship moves out of the line of fire the unpowered missile would just miss since their paths would no longer intersect. Note this is similar to character scale combat where a character moves behind solid cover and can no longer be hit. No dodge needed.

[Fallon Kell]

[Bren]

Sure, but it isn't a piloting roll (or dodge) to evade. It is just moving out of the line of fire.

[Ankhanu]

[atgxtg]

Overall this looks pretty good to me, just ask Bren

My reservations are the same as Ankhanu's. Mostly, I like to keep atmphereic speed. Maybe use 1/4 kph speed to some sort of sclae (like 100kph = 1 unit).

As for "unpowerred" proectiles, I7d think that they probably would miss thier target unless the target was very close of stopped dead. Practially any change i course would be successful at the distances involved in pace combat. A 1 degree course alteration over a distance of 100 km will put the target over 1km out of the way.

Why not just increase the flight time a little and say a unpowerred missile simply misses the target?

[Bren]

[Fallon Kell]

[Bren]

[atgxtg]

Yeah, speed really ins't the issue.

For example, if a ship acclerates at 1G for a round (5 seconds), it can change it's position by by about 125 meters. which is more than enough to get it off the flight path of an unpowered object. Now we all agree that starfighters must br able to accelerate at more than 1G, so our differences in how fast the ships can accelerate isn't really an issue.

About the only exceptions I can see are:

1) If the misile if right on top of (within 1 SU) of the target, limiting the target's response time.

2) If the target is dead in space, and can't move out of the way.

3) if the target is really big and can7t get it's entire bulk out of the way. For instance, the Death Star is a pretty much a sure thing.

[Fallon Kell]