On October 18, 1972, in the Senate debate concerning the Noise Control Act of 1972, then-Senator John V. Tunney of California stated the purpose of the Noise Control Act:
Both the Senate and the House were most concerned with the problem of aircraft noise and, more specifically, with the need to protect public health and welfare in the vicinity of airports from the impact of noise from aircraft operations.
. . . .
Such regulations would be required to include proposed means of reducing noise in airport environments through the application of emission controls on aircraft, the regulation of flight patterns and aircraft and airport operations, and modifications in the number, frequency, or scheduling of flights.
. . . .
Again, I stress that those regulations would include, but would not be limited to, the imposition of curfews on noisy airports, the imposition of flight path alterations in areas where noise was a problem, the imposition of noise emission standards on new and existing aircraft – with the expectation of a retrofit schedule to abate noise emissions from existing aircraft – the imposition of controls to increase the load factor on commercial flights, or other reductions in the joint use of airports, and such other procedures as may be determined useful and necessary to protect public health and welfare.
. . . .
Congress intends that the reasonableness of the cost of any regulation or standard be judged in relation to the purposes of this act, which is to protect public health and welfare from aircraft noise. Costs are to be judged against that goal, not for their effect on air commerce or particular air carriers.
(Emphasis added). Here it is 43 years later and the FAA has not promulgated the regulations that Sen. Tunney stressed. Nor does the FAA judge the reasonableness of the cost of regulation against the goal of protecting public health and welfare from aircraft noise.
Aviation and Airport Development News 
Yes. It seems that FAA moves in mysterious ways and does not follow the will or intent of the Congress on this and other matters. By the same token, Congress does not exert its oversight responsibilities as it should and as it is obligated. So, unless the general public stands up and shouts “enough”, the law is disregarded. Additionally, FAA issues Orders and Handbooks that reflect its interpretation of the laws, seeks comments from the industry that, in this case, work to diminish the intent of the legislation. It’s time to separate the FAA from its aviation regulatory and promotion roles. This has been a longstanding matter in the industry. Maybe the next round of FAA authorizations can address it more fully.