Comparison of Noise from Aircraft Using Lambert
The "noise footprints" shown below depict the amount of noise generated by various types of aircraft that commonly operate at Lambert. As you can see, military aircraft now using Lambert generate a much larger amount of noise than commercial aircraft. Modern commercial aircraft are known as "stage 3 aircraft," distinguishing them from the "stage 2 aircraft" that frequently used Lambert in the 1990s. Stage 2 aircraft weighing over 75,000 lbs. are no longer permitted at commercial airports in the U.S. unless they have been retrofitted with hushkits to meet stage 3 requirements. Such aircraft that have been "hushkitted" include the DC9-30.
