Accession Number : AD0923562

Title :   Comparison of the Basic F-4E and the Slatted F-4E Stall/Near Stall/Spin Characteristics,

Corporate Author : MCDONNELL AIRCRAFT CO ST LOUIS MO

Personal Author(s) : Pelikan, Ralph J.

Report Date : 01 AUG 1973

Pagination or Media Count : 277

Abstract : This report presents the results of a six-degree-of-freedom analytical study to examine the stall/near stall/spin characteristics of the slatted F-4E aircraft. The basic F-4E and the slatted F-4E are analyzed and compared. Primary emphasis was directed toward the stall/near stall characteristics. Some analyses of spin characteristics and recovery techniques were also accomplished. Departure and post stall characteristics are analyzed in detail. The primary points of interest are: (1) types of entry into the stall, (2) the effect of lateral-directional control inputs on the departure characteristics, (3) recovery techniques, and (4) evaluation of five methods that predict the point at which the aircraft becomes lateral-directionally unstable. The previous F-4 spin evaluation developed a dynamic model whereby rotary balance and forced oscillation data are utilized to compute the spin and spin entry motions. Further development of this dynamic model has been accomplished so that it can be used in both the unstalled and stalled flight regimes. Transition between the two regimes can be smoothly accomplished. Based on the investigation, recommendations are made relative to the techniques for recovery from a departure and for preventing departures through the use of control surfaces. A comparison of the slatted F-4E flight test stall/near stall characteristics with the analytical characteristics are qualitatively evaluated.

Descriptors :   (*JET FIGHTERS, STALLING), (*JET FIGHTERS, SPINNING(MOTION)), AERODYNAMIC CHARACTERISTICS, DEGREES OF FREEDOM, AERODYNAMIC STABILITY, MATHEMATICAL PREDICTION, FLIGHT MANEUVERS, LEADING EDGE FLAPS, ANGLE OF ATTACK, HANDLING, COMPUTER PROGRAMS, DIGITAL COMPUTERS, SIDESLIP, WIND TUNNEL TESTS, WIND TUNNEL MODELS, ANALYSIS OF VARIANCE, AERODYNAMIC FORCES, MOMENTS, FREE FLIGHT MODELS, CENTER OF GRAVITY, RECOVERY, EXPERIMENTAL DATA, EQUATIONS OF MOTION, NUMERICAL METHODS AND PROCEDURES.

Subject Categories : Attack and Fighter Aircraft

Distribution Statement : APPROVED FOR PUBLIC RELEASE