Three sets of parameters#

The hull defines mass and motion response. Engines define longitudinal thrust and boost/travel modes. Thrusters define lateral thrust and rotation. Resulting speed belongs to the selected combination of hull and equipment.

Table paths start inside the properties of the relevant macro. Parameter meanings were checked against Flight Parameter Setup, Daniel Turner. The guide includes 7.50 notes; distinguish a field found in 9.00 from its active runtime behavior.

Engine: thrust and modes#

Path Type / units Meaning
thrust/@forward, thrust/@reverse Numeric thrust parameters Forward and reverse thrust; not speed in metres per second
boost/@duration Number, seconds Boost duration from full boost capacity
boost/@thrust Dimensionless multiplier Base-thrust amplification during boost
boost/@acceleration Dimensionless multiplier Boost acceleration amplification; separate from thrust
boost/@release Number, seconds Coasting interval after boost before amplified braking
boost/@coast Dimensionless multiplier Deceleration adjustment during the release interval
travel/@charge Number, seconds Delay before travel mode engages
travel/@thrust Dimensionless multiplier Base-thrust amplification in travel mode
travel/@attack Number, seconds Time to reach maximum travel speed according to the guide
decelerationcurve/point Position/value pairs Longitudinal braking amplification curve
strafecurve/point Position/value pairs Lateral deceleration curve across speed regimes

travel/@release still exists in the inspected 9.00 engine macro, but the guide marks that braking control as deprecated. Attribute presence alone does not establish an effect; inspect reverse thrust and braking curves.

Thrusters and hull#

Location Parameter Effect
Thruster macro thrust/@strafe Lateral thrust
Thruster macro thrust/@pitch, @yaw, @roll Rotational thrust: pitch, yaw and roll
Hull macro physics/@mass, physics/inertia, physics/drag Mass, inertia and resistance by axis
Hull macro physics/accfactors Acceleration multipliers for individual directions
Hull macro jerk Smoothing when acceleration rises or falls
Hull macro steeringcurve/point Steering-speed multiplier across speed regimes

In jerk, accel/decel and value control smoothing; ratio changes the transition shape. These are neither seconds nor thrust. Curve value is a multiplier; position identifies regular, boost or travel speed regions. position="2" does not mean 2 metres per second; the upper regimes depend on their maximum speeds.

Example: only the selected engine thrust#

For engine_arg_s_allround_01_mk1_macro, the 9.00 base forward value is 384. Patch file: assets/props/Engines/macros/engine_arg_s_allround_01_mk1_macro.xml.

XML
<diff>
  <replace sel="/macros/macro[@name='engine_arg_s_allround_01_mk1_macro']/properties/thrust/@forward">422.4</replace>
</diff>

Expected data result: forward thrust rises by 10%; reverse thrust and other fields remain unchanged. This does not promise exactly 10% more speed or acceleration in every mode. The shared engine resource changes, so the scope is not limited to one Elite.

replace writes the absolute value 422.4; it does not multiply the current value by 1.1. If another mod changes the engine, compare the effective XML and load order.

One reproducible comparison#

Record the hull, engine, thruster and in-game modifications. On a new instance, measure regular speed, acceleration, boost, travel charging, braking and turning. Change one field and repeat the same actions in the same place. XML values were checked by reading; this example has not been run as a new game test.

For a change limited to one hull variant, first choose the scope: hull properties or a separate equipment resource. Do not change slot sizes to tune speed: see equipment compatibility.