Abstract
Optimal control theory is used to determine thrust and glide path angle programs for minimum time or minimum noise landing approach of aircraft modeled by an approximated point-mass dynamics. Necessary conditions for optimal programs are derived and numerical results are presented for a small jet airplane. Significant noise abatement and savings in time are obtained compared with reference thrust and path angle programs. The minimum time solution indicates; 1) thrust is a dominant control, and glide path angle γ has little influence on the performance index; 2) Optimal path mainly consists of a constant velocity descending path, which is a singular solution, and a decelerating path with γmax. Optimal thrust switches from its maximum to its minimum on the latter path. The minimum noise solution indicates; 1) optimal thrust has neither its maximum nor its minimum, and varies continuously so as to achieve a smooth EPN level curve; 2) optimal path mainly consists of a decelerating horizontal path and a decending path with γmax. These results may be regarded as a theoretical base for a two-segment approach for noise abatement and time savings.
