FlightGear base package audio, unmodified WAV files.
Source: https://github.com/FGDATA/fgdata/tree/master/Sounds
License: GNU General Public License version 2 (COPYING included).
Authors: FlightGear contributors (AUTHORS included).
This audio directory is a separately licensed collection of sound assets.
Files: altitude-200.wav, altitude-100.wav, altitude-50.wav, altitude-40.wav, altitude-30.wav, altitude-20.wav, altitude-10.wav, terrain.wav, pull-up.wav, sink-rate.wav, glideslope.wav, bank-angle.wav, wind.wav, jet.wav, rumble.wav, squeal.wav
Retrieved 2026-09-13.

Windshear: synthesized at playback by the browser speech engine; not a FlightGear or OEM recording. Warning thresholds are simplified game rules.

Retard: original browser-synthesized voice cue after the 10 ft callout in this arcade game. Thrust automatically idles below 20 ft on final; no throttle control is required. Not an OEM sound or certified warning logic.