It’s not only small airplanes that run into trouble with neighbors over noise — plenty of folks in crowded cities around the world live beneath the approach paths of passenger jets, and the noise is a major bone of contention. In a new research project launched in Britain this month, scientists are examining a number of solutions, from jiggering the approach paths to allow for quieter descents, to designing new jets that will be capable of “silent” takeoffs and landings. The researchers will analyze options such as mounting the engines above the wing or eliminating the tail surfaces, as well as looking at operational changes such as holding off on lowering landing gear till later in the descent and stabilizing the approach at higher altitudes. Experts from British Airways, Rolls Royce, Cambridge University and the Massachusetts Institute of Technology will participate in the study. “We are aiming for a radical change in noise levels — so that beyond the perimeter of the airport, the noise of aircraft flying would imperceptible to the public,” said Prof. Ann Dowling, of the engineering department at Cambridge. Meanwhile, in the U.S., the majority of funds spent to reduce noise problems at airports large and small has gone to acquiring nearby land and soundproofing buildings. From 1982 to 1999, the FAA spent at least $4.3 billion on noise mitigation. In September, the FAA also established a research program with eight universities and 18 industry partners to investigate noise-mitigation solutions.
