文档介绍：Project Assignment #3
Cruise and Approach Analysis of BWB
Due: October 19 at the end of lab
Prof. David L. Darmofal
Department of Aeronautics and Astronautics
Massachusetts Institute of Technology
1 Objective
The objective of this Project Assignment is to determine if the approach and cruise design con­
straints can be met by the BWB. This determination will be made using the aerodynamic models
developed and validated in the previous Project Assignments.
2 Operating Condition Specifications and Constraints
Cruise
1. Cruise altitude is 39,000 feet
2. Mach number, M =
3. Assume cruise weight is Maximum take-off weight (MTOW), and MTOW = 800,000 lbs.
4. 5% static stability margin (see Section 4 for more on static stability).
5. Flaperons are not to be deflected in cruise.
Approach & Stall
1. Approach speed = 150 knots (set by air traffic safety)
2. If the sectional clmax < , then slats will not be needed in the design. With slats, then
cl max = . Note: these limits will set the maximum lift and, therefore, determine the stall
speed. In either case with or without slats, the winglet cl’s are not required to be below clmax.
3. Approach speed = × stall speed (for safety)
4. Aircraft is carrying full payload with 25% fuel remaining. Assume aircraft empty weight is
400,000 lbs, payload is 200,000 lbs, and