Continuous descent approach
Continuous descent approach (CDA), also known as optimized profile descent (OPD), is a method by which aircraft approach airports prior to landing. It is designed to reduce fuel consumption and noise compared to other conventional descents. Instead of approaching an airport in a stairstep fashion, throttling down, and requesting permission to descend to each new (lower) altitude, CDA allows for a smooth, constant-angle descent to landing. A continuous descent approach starts from the top of descent, i.e., at cruise altitude, and allows the aircraft to fly its individual optimal vertical profile down to runway threshold. Some airports apply constraints to this individual optimal profile. United Kingdom The approach to London Heathrow Airport uses CDA, particularly at night, to minimize noise pollution. It is also used at Gatwick Airport. See also List of aviation, avionics, aerospace and aeronautical abbreviations Index of aviation articles QTOL Nap-of-the-earth References Air traffic control