Development of continuous descent approach concepts for noise abatement [ATC]

One major problem for airports today is the noise and environmental effects of conventional aircraft approach procedures. Conventional approach procedures, for example, often descend aircraft to intermediate altitudes on the order of 2000 to 3000 feet, before transitioning onto the final approach path and final descent to the approach runway. The effect of such procedures is to spread noise and aircraft emissions onto nearby communities, sometimes as far away as 30 miles from the runway threshold. Continuous descent approach (CDA) procedures have been proposed to reduce noise and emissions by (1) delaying descent below 7000 feet as late as possible, and (2) descending at idle or near idle thrust from about 220 knots until final approach speed is reached. This paper describes near-term, mid-term, and advanced operational concepts for FMS (flight management system) based CDA system deployments.