Accession Number : ADP005671

Title :   Introduction to FMP Lecture Series Number 153 on 'Integrated Design of Advanced Fighters,'

Corporate Author : CALIFORNIA UNIV BERKELEY

Personal Author(s) : Laitone, E. V.

Report Date : MAY 1987

Pagination or Media Count : 6

Abstract : The history and philosophy of aircraft design optimization will be briefly covered from the very beginning of the Wright Brothers first flight through some of the most anomalous aerodynamic design errors during both World Wars. It will be shown how either the lack of adequate theory, or the misuse of inadequate wind tunnel tests, led to the adoption of erroneous criteria for the optimization of fighter aircraft design. The first example will show why the World War I fighter aircraft used very thin wing profiles because the wind tunnel tests were all conducted at too low Reynolds numbers. Then the improved design criteria that became available with both wind tunnel tests at higher Reynolds numbers, and the proper use of Prandtl's induced drag theory will be discussed. The next examples will show how adverse compressibility effects were encountered during World War II as the flight Mach number increased during a steep dive. Again, adequate wind tunnel tests at higher Mach problems of tuck under and elevator snatch will be briefly discussed. Then the severe problems of roll control for slender delta wing aircraft, and their inertia crosscoupling, will be introduced to show how analog and digital computer programs finally provided additional design tools that would in some cases surpass the wind tunnel. Finally, it will be indicated how the advent of the high speed digital computer has completely revolutionized the design optimization of all aircraft.

Descriptors :   *FIGHTER AIRCRAFT, INTEGRATED SYSTEMS, JET FIGHTERS, AERODYNAMIC CHARACTERISTICS, REYNOLDS NUMBER, WIND TUNNEL TESTS, MACH NUMBER, AIRFOILS, LIFT TO DRAG RATIO, COMPUTER PROGRAMS, DIGITAL SYSTEMS, FLUID MECHANICS, LEADING EDGES.

Subject Categories : Attack and Fighter Aircraft
      Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE