# Engine sound sources

The turbine tones, airflow, resonant whine, low-frequency body, spatial response, and ignition transient are synthesized by `web/sound.js`. A restrained natural afterburner bed is derived from a public-domain U.S. Air National Guard recording:

- Master Sgt. Andrew Moseley, 177th Fighter Wing, New Jersey Air National Guard. [177th Fighter Wing gas turbine engine testing](https://www.dvidshub.net/video/512154/177th-fighter-wing-gas-turbine-engine-testing), recorded January 31, 2017; published March 2, 2017.
- Source identifies a General Electric F110-GE-100 engine under full-afterburner testing. This is a sound-design texture for an original visualization, not an assertion that the AD-5 model is that engine.
- DVIDS labels the work PUBLIC DOMAIN. Its [use notice](https://www.dvidshub.net/about/copyright) was checked September 12, 2026. No logos, personal voices, music, or claims of sponsorship are incorporated into this audio layer.
- The public audio stream was retained under `research/audio/177th-engine-test.m4a`. `afterburner-bed.wav` uses source seconds 10–18, converted to mono 24 kHz PCM, high-passed at 35 Hz and low-passed at 8 kHz. The browser crossfades its loop boundary and varies level, slight playback rate, filtering, and spatial position.
- Native-audio review of source seconds 10–34 reported continuous machine roar without speech or music. The review is an auditory observation, not a rights determination or acoustic calibration.

“The appearance of U.S. Department of War (DoW) visual information does not imply or constitute DoW endorsement.”