SKYLINE vehicle audio credits

Engine idle recording:
"racing car engine sound loops" by domasx2, CC0 1.0.
https://opengameart.org/content/racing-car-engine-sound-loops
https://creativecommons.org/publicdomain/zero/1.0/
Source file: loop_0.wav.

Engine load recording:
"Car engine loop 96kHz 4s" by qubodup, recorded for Trigger Rally.
Licensed under Creative Commons Attribution 3.0 Unported.
https://opengameart.org/content/car-engine-loop-96khz-4s
https://creativecommons.org/licenses/by/3.0/
Source file: engine-loop-1-normalized.wav.

Tire skid recording:
"Car tire squeal skid loop" by audible-edge (Tom Haigh), loop edit by qubodup.
Licensed under Creative Commons Attribution 3.0 Unported.
https://opengameart.org/content/car-tire-squeal-skid-loop
https://creativecommons.org/licenses/by/3.0/
Original recording: https://www.freesound.org/people/audible-edge/sounds/71739/

Modifications: converted to mono PCM 16-bit / 24 kHz, level normalization,
DC removal and a 20 ms overlap at the loop seam. Runtime pitch, filtering
and volume change with engine load, gear and tire slip.

2026-10-22 mix revision: continuous wheel-speed engine pitch, reduced saturation,
no scripted gear/exhaust/turbo effects; independent tire layer with faster attack,
stronger gain and engine ducking while braking. These are our own mappings of
licensed recordings; no PolyTrack audio files are distributed.

2026-10-23 airborne and landing revision: held airborne throttle retains audible
engine revs and adds a small body/load gain increase. Landing impact/scuff is an
original procedurally synthesized 0.24 s sound (landing.wav), made for SKYLINE;
no external recording or PolyTrack audio is used in that effect.