Thruster

Screenshot assets/wiki-section-thruster.png A thruster burning, exhaust plume lit, ideally on a multi-thruster build.

The thruster produces forward thrust and drives the exhaust plume. Throttle is analog, so a build's thrust authority comes from each thruster's magnitude and how many you fit - more thrusters, more push. What that push is worth is the other half of it: a section weighs the box it is hit on, so a roomy hull is a slow one and no part of it says so anywhere. The skin plates that clad every base hull add weight of their own, so a clad ship is heavier than its sections alone.

Every drive here pushes with the same 1.0, and all three of these salvage hulls fly on exactly two of them. The skiff's structure weighs 28.13, good for at most 46 m/s^2; the tug's weighs 48.00, good for at most 27 m/s^2, on the same pair of engines. Nothing authors that gap - a section's mass is the volume of the box it is hit on. These are upper bounds: the scope counts structure only, and the skin plates on a base hull make it heavier and slower. Bolting basic drives on closes the gap, with a tapering return: each one is a unit of mass as well as a unit of push, and no stack of them passes 640 m/s^2 - what a single drive would do carrying only itself.

A thruster bolts on by its forward end and by that end only. The rest of it is barrel, nozzle bell and exhaust, so the builder always seats it nose-in with the plume clear of the ship - you choose the face it grows from, not which way round it sits.

Balancing thrust through the hull

Because thrusters sit wherever you bolted them, an off-center burn would spin the ship. The flight computer prevents that: it sets each engine's throttle to deliver the commanded forward thrust while cancelling the twist through the live center of mass, recruiting off-axis thrusters purely for counter-torque when the firing set cannot balance itself. An asymmetric or battle-damaged ship still flies straight - any tiny leftover spin is mopped up by the steering - so a drive shot off one flank costs you push, not control.

What a hurt drive tells you

A hurt drive looks hurt. Past about a third of its health gone it cracks and throws sparks, and its exhaust runs short and guttering instead of steady. It never guts all the way out, because a dead plume means a shut-down drive and this one is not shut down: a damaged thruster delivers exactly the push a fresh one does. The plume tells you what a chaser has already taken off it, not what it can still do.

Loop capture assets/loops/loop-section-thruster.webm A short loop: throttle rolling up, plumes brightening, the ship pulling away.

Variants

Three drive grades ship, and they are priced by the space they take: the basic drive is a unit cube pushing 1.0, the vector drive is a 3x3x2 block pushing 9.0, and the capital drive is 5x5x3 pushing 25.0. Thrust per unit of mass FALLS as they grow - 1.0, then 0.5, then 0.33 - so a large drive buys a large hull fewer mounts to defend and a shorter drive bay, not a better deal. All three bolt on by their forward face only, plume clear of the ship.

assets/icon-thruster.pngThruster - shipped prototypes

	Variant	Box	Thrust	Health
captureassets/catalog-basic-thruster-section.png	Basic Thruster Sectionbasic_thruster_section	1x1x1	1.0	70
captureassets/catalog-vector-thruster-section.png	Vector Thruster Sectionvector_thruster_section	3x3x2	9.0	480
captureassets/catalog-capital-thruster-section.png	Capital Thruster Sectioncapital_thruster_section	5x5x3	25.0	1250