Subjective response to low-frequency aircraft noise

The standard metric currently in use by the U.S. government for community noise from aircraft is the Day-Night Level (DNL), which is based on the A-weighting network. However, residents of communities near airports have reported annoyance due to aircraft noise in greater proportion than what the DNL contour associated with their address predicts¹. Complaints of "distant rumbling" appear to be related to the low-frequency noise that aircraft produce for which the DNL metric does not fully account ². This presentation discusses measurements made in October 2004 at two residences near runways at Washington-Dulles International Airport. Noise data are recorded on indoor and outdoor microphones, allowing for a measure of the events' impact both inside and outside the structure, as well as the filtering effect of the structure on the signal. Experimental design for a laboratory subjective study of the recorded aircraft signatures is discussed. Objective metrics, those that are designed for low-frequency noise and those that are not, are to be calculated and correlated with subjective rankings of the signatures. These correlations will gauge the metrics' effectiveness in predicting subjective perception of aircraft noise signatures.