abstract:Continuous descent approach (CDA) or 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 certain conventional approaches and involves maintaining a constant three degree descent angle during landing, until meeting the instrument landing system (ILS).
NextGen will allowplanes to make what is calleda continuous-descentapproach (CDA), essentially letting them turn off their engines, saving tons of fuel and reducingpollutants.