For stratospheric quasi-steady cruise flight (supersonic or subsonic), optimal flight conditions for minimum operating costs are presented in a closed form. Constant power setting and thrust variations proportional to air density are assumed. When these assumptions conform to practical conditions, the drag polar may be of arbitrary shape. Drag polar, thrust and fuel consumption depend on the Mach number in arbitrary but defined form. A constant wind parallel to the flight path and the reduction of the aircraft weight due to fuel consumption are taken into account. Minimum fuel as well as minimum time cruising trajectories are contained in the solution as special cases. (Author)
A Closed Form Variational Solution of Stratospheric Cruise Flights with Minimum Direct Operating Costs
1976
29 pages
Report
No indication
English