Aeronautic Indicators

Aeronautic Indicators are useful for cabin noise evaluation and they compute the Speech Interference Levels in dB SIL3, dB SIL4, dB PSIL and the sound level dB(G).

  • Speech Interference Level in dB SIL3 corresponds to the arithmetic mean of levels in octaves 1000, 2000 and 4000 Hz.

  • Speech Interference Level in dB SIL4 corresponds to the arithmetic mean of levels in octaves 500, 1000, 2000 and 4000 Hz.

  • Preferred-octave Speech interference Level in dB PSIL corresponds to the arithmetic mean of levels in octaves 500, 1000 and 2000 Hz.

  • Sound Level in dB(G) measures the weighted physical level for infrasound components of the power spectrum (centered on 20 Hz). See standard ISO 7196 for more details.