The FAA’s final rule on civil tiltrotor noise limits and conditions for noise compliance measurement becomes effective March 11. It amends regulations governing noise certification standards and establishes new noise limits and procedures to ensure that noise-reduction technology is incorporated in tiltrotors.
The FAA issued a proposed rule on Tuesday that is aimed at reducing noise generated by new helicopters certified under Part 36 (noise standards) of the FARs. If adopted, the rule would impose standards already adopted by ICAO.
Just a few years ago Eurocopter scored a major coup at an HAI Heli-Expo show, amazing the crowds by introducing a new helicopter as a completely certified aircraft instead of a promise-laden prototype encumbered with the usual waits for first flight, inflated claims of launch customers and delays in FAA approval. Instead, Eurocopter presented its EC 130 as a done deal.
Noise is everywhere–annoying, tiring and sometimes painful. Since the early days of aviation, when a roaring, clattering engine sat on a wooden frame close to the pilot, and the wind whistled through the wire bracing like a banshee chorus, engineers have sought to make the process of manned flight less noisy. And they have succeeded, to a degree.
Business aircraft crews and passengers are generally aware of the danger of prolonged exposure to noise in terms of hearing loss. Now there is a growing body of evidence that prolonged exposure to a combination of high-intensity and low-frequency noise may pose far more serious health threats.
All jet and transport-category airplanes (those with an mtow of 12,500 pounds or more) for which application of a new type design is submitted on or after January 1 this year have to meet new noise certification levels. Stage 4 is a cumulative 10 EPNdB (effective perceived noise level in decibels) less than Stage 3 limits. Virtually all in-production business jets will qualify to be recertified under Stage 4.