Cadet II/Ship control

Steering your ship using Alleg physics

One of Allegiance's charms is its semi-realistic physics engine. It is not truly Newtonian space physics but is "Newtonian enough" to capture some of the essence of flying in space. This lesson is intended to clear up misconceptions, and recommend some strategies for proper steering in Allegiance.

Basic concepts

Drag

In "True Newtonian" physics any space object subject to a brief acceleration will speed up then drift forever at that top speed. An object subject to a constant acceleration will constantly speed up and never reach a top speed (until you get close to light speed and start having to mess around with "Relativistic" physics).

To change direction an object must first "bleed off" all the speed it has gained in its original direction. For instance if it wants to do a U-turn it must first accelerate in the opposite direction until it stops, then it further acceleration will get it moving the other way. If it wants to do a right-hand turn then it must not only accelerate to the right, it must also accelerate backwards to get rid of its forward movement - if it just accelerated to the right it would end up moving at a 45 degree angle because the rightwards movement and the forward movement would combine.

Allegiance physics functions pretty much the same, except that Allegiance space has an incredible amount of space debris that acts as "drag" on your ship (you can turn on Debris under the graphics options). This drag means that your ships require constant acceleration to keep moving, if you turn your engines off then your ship will drift to a stop. You also have a top speed when the drag against the front of your ship equals the propulsion from your engine.

Tip: One of the best analogies for how Allegiance ships work is that they are all flying underwater.

Throttles vs thrusters

Your throttle only controls your main engine at the rear of the ship, and it is nearly always more powerful than your side-thrusters. The throttle controls how much of your engine power is going to the main engine when the side-thrusters are not being used, and it's effectively a 'cruise control'. At 50% throttle you will accelerate forwards at half the rate you normally do and reach a top speed half of your normal top speed.

You also have side-thrusters that allow you to travel left, right, up, down, forwards and backwards. If you press down on a side-thrust key then all of your engine power is diverted into this direction - however it is a lot more inefficient. Depending on your ship and your faction then these side-thrusters can range from 25% to 100% as powerful as the main engine.

If you press down on two side-thrust keys at the same time then 50% of your engine power is diverted into each direction.

Overuse your side-thrusters in an un-agile ship and the constant diversion of power from your main engine will slow you down and make you a sitting duck. Many veterans hold the forward side-thrust key at the same time they are using one of the others, so that 50% of engine power is diverted into the more powerful main engine at the rear of the ship.

Auto-engaging thrusters

In some situations your side-thrusters will engage to control your movement automatically. Unlike if you use the side-thrust key manually, when they are doing this they don't use 100% of the engine power if it's not required, which can mean you maintain a higher speed for longer.

One such situation is when you use vector lock. When you engage vector lock all your thrusters operate to maintain your current direction of motion despite the direction you are facing. If you face the same direction as your vector lock, then it will use 100% of your powerful rear thruster. If you face precisely sideways, it will use 100% your side thruster. If you face somewhere between these two extremes it will use some side-thrust power and some main engine power.

No matter how efficient vector lock is at splitting the power between thrusters the fact is that your side thrusters are weaker, and facing any direction except your vector lock then you will begin slowing down. Many veterans believe that the advantage of traveling in one direction while shooting in another is more than offset by the disadvantage of being a target that is moving in a straight line (easy to aim at) and being a target that is slowing down (easier to aim at).

Turning and the G-indicator

When you turn your ship the main engine swings around to point in a different direction and it begins accelerating you in the new direction you are facing. However, just like starting from a stand still it takes some time to get you up to top speed in this new direction. In the meantime your ship continues to drift in the same direction it used to be flying, until "drag" overcomes it and it stops moving in this direction. So your ship carves out a little arc in space.

The G-indicator (shown as on the screen) always indicates the direction your ship is currently "drifting". This "drifting" is known scientifically as your "current momentum". The location of the G-indicator can give you a clue as to how close you are to completing a turn, when it is centered the turn is finished. How long this takes depends on your ship, faction, and how sharp your turn is. If you did a 180 turn so that your main engines are acting directly against your old momentum then it's going to take a long time!

Acceleration vs agility

Acceleration is, among other things, a measure of how long it takes for your ship to change direction. Ships with high acceleration can stop on a dime, meaning that it takes their g-indicator very little time to align with the nose of their ship. Interceptors are a great example of a ship with high acceleration. As you know, what you pack in cargo greatly affects your ship's acceleration. Pick up LRM Aleph Resonator from space, and notice how hard it is to suddenly change your direction. The Expansion Complex provides two 10% increases to ship acceleration.

Agility is a measure of how quickly your ship changes its orientation in space (ie. turns). Ships with high agility can whip around much faster than their thrusters can change the ship's direction of motion. As a result, a ship with high agility can turn to attack a target before the negating effects of the ship's side thrusters makes it harder to aim. Agility upgrades can be found in the Supremacy Center.

For many ships, gentle turns allows the ship's acceleration to keep pace with its agility, allowing the g-indicator to stay consistently centered. With more drastic turns, a ship's agility outpaces its acceleration, causing your ship to move in an arc while the thrusters work to change your direction.

Boosting

Your ship's booster simply provides additional forward thrust at the cost of fuel. It is a "strap on" component, rather than an integrated part of your ship's thrust system. You can not divert booster-generated thrust through a side thruster, though Community Core does provide a "retro-booster" for scouts that generates backward thrust. The main purpose of the retro-booster is to augment the stopping function of the rear thruster, allowing scouts to stop quickly.

Incidentally, like manually engaging thrusters, holding down the boost key will prevent your thrusters from automatically engaging. This is true, even if you don't have a booster installed. This is a common cause of overboosting, because pilots will hold down the key too long (preventing their ship from decelerating). It is also much harder to steer accurately while boosting (since you're relying solely on your boosters and drag to cancel your old direction of motion), so changing direction to intercept a target may become difficult.

You can use this behavior to your advantage. A common trick is to hold down the boost key just before you start to ripcord. The ship will continue coasting forward for most of the ripcord sequence. If you are out of fuel (or reloading fuel), you can hold down the boost key to replicate vector lock. As long as you're not boosting, you can throw yourself in one direction and use the boost key to "slide" in that direction while you turn your ship to engage an enemy. This isn't quite like vector lock (the drag in space will cause you to stop), but it is a quick/handy trick for those who master it.

Applications to common problems in flight

Oversteering

As we discussed previously, turning engages your side thrusters to cancel your previous direction of motion, while your forward thruster propels you in a new direction. Yet, it is frequently helpful to you want to cancel your previous direction as fast a possible, trusting your main thruster to get your moving quickly in the new direction once you've stopped moving in the old one. A common scenario where this is the case is trying to dock/transfer as quickly as possible to meet some imminent threat.

You can increase the speed at which you turn by oversteering, or turning farther than you intend to go. When you oversteer, you use your ship's powerful main thruster cancel your previous vector, rather than your weaker side thrusters. While your main thrusters are working, watch for your g-indicator to appear, and track its motion. When the g-indicator is lined up with where you really want to go, immediately point your ship back towards the intended target (having good agility helps). As your g-indicator is now centered with the nose of your ship, your forward thrusters will fully engage and you'll gain speed very quickly. Boosters are of great help while oversteering, since the additional thrust will let you almost-instantly cancel your old vector.

Of course, the question of "how much to oversteer" is important. You typically don't want to oversteer so much that your intended target is off screen. It is important to know when the g-indicator is pointing in the right direction so that you can turn back. If you have a really good feel for your ship, you can get away with oversteering so much that your intended target is off screen. Don't try it when you're just starting out though.

A good place to start is to oversteer so that your target is somewhere between the edge of the screen and half the distance from edge to middle. If you're moving perpendicularly to an aleph and want to boost through it, turn so that the aleph is right on the edge and boost until you see the g-indicator line up with it. Then stop boosting, turn around, and boost again toward the aleph.

Intercepting a target

Suppose you're a stealth fighter, wanting to intercept a miner traveling across a sector. Suppose you are an interceptor, wanting to unload on a bomber traveling across your screen. Suppose you want to chase down a scout that has been camping in your home. There are many situations where you want to meet up with a target moving laterally across your screen. Plotting an intercept course with a distant target is not a trivial task for a human. However, with a few easy tips, you can improve your chances of "crossing the t" of an enemy's target (to use naval jargon).

The biggest tip is to not aim directly for the target, unless you are moving very fast and are reasonably close (ie. almost in gun range). If you aim directly for a distant target, you'll end up always turning to keep the target in the center of your screen. Since turning engages side thrusters and reduces your speed, you'll consistently end up falling behind the target as you get closer to it. This is a decent strategy if you want to leisurely line up and take a shot at a bomber's nans, or settle in for the right moment to unload on a miner. In a time-crunch situation, however, falling behind the target means that you'll be playing catch-up just as a miner gets to safety or a bomber begins unloading anti-base missiles.

Instead, you want to lead the target. Precisely how much to lead is hard to say. One method is to put the targetted ship off of the edge of the screen and monitor its motion as the distance to it closes. As the distance closes, the target ship should begin to work its way to the middle of the screen. If you're 1k from the target and it is still off the edge of your screen, make an adjustment and turn a bit towards the target. If the ship is halfway to the middle of your screen and you're 3k away, make another adjustment and turn away from the target. You'll probably have to make little adjustments as the distance closes. That's fine. Minor, periodic adjustments won't hurt your overall speed that much. Peeking in f3 helps if you can get away with it. Sometimes you can't, but it is a great help when you can.

Exploiting the forward thruster

It is frequently the case where you don't care exactly where you are going, so long as you are going fast. You might be a scout running away from a boosting interceptor, or a bomber wanting to travel vaguely in the direction of an enemy base. Either way, you can enjoy better results by manually engaging your forward thruster.

Recall that manually engaging any thruster causes the ship the maximize its thrust output, while also preventing any other thruster from auto-engaging. This feature can be exploited to make high speed turns without losing much speed. If you turn with your forward thruster engaged, your side thrusters will not try to cancel your old vector (and thus not divert any power from your forward thruster). The drag in space will allow you to still execute the turn, but it will take much longer. This is not something that I would try in the middle of an asteroid field: you stand a good chance of sideswiping a Helium rock (and entertaining the enemy). If you're at the edge of a sector and want to make a pursuer work harder to kill you, this the trick to use.

Your bomb/htt runs can also benefit from this technique. As mentioned above, your rear thrusters will automatically try to slow down a bomber/htt after it has been rammed. Holding down your forward thruster key will prevent this from happening, allowing you to maintain a higher speed for longer. It also prevents your side thrusters from trying to adjust from a wonky ram, letting you keep a higher speed at the cost of accuracy. The loss of accuracy is important to note, because even if you get really good rams, your bomber will be hard to steer with the forward thruster engaged. This is not a technique that I would use close to an enemy base, especially on an htt run. It also dangerous to use if the enemy has a skilled prox dropper. However, if you want to traverse an empty sector, or cover most of the distance to a base, this is a useful technique.