Accession Number : AD0671081

Title :   EVALUATION OF THE PIPER PA-25B AGRICULTURAL AIRCRAFT.

Descriptive Note : Technical rept.,

Corporate Author : MISSISSIPPI STATE UNIV STATE COLLEGE DEPT OF AEROPHYSICS

Personal Author(s) : Smith,Michael R. ; Patrick,John D.

Report Date : NOV 1966

Pagination or Media Count : 79

Abstract : The aircraft was evaluated in three configurations: (1) clean or basic aircraft, (2) basic aircraft with spray dispersal equipment attached, and (3) basic aircraft with the granular material distributor attached. Level flight power required tests and climb performance tests indicate that the dispersal systems greatly reduce the economy and safety of the aircraft in agricultural operation. The results indicate that the efficiency of the dispersal systems must be increased before improvement in the aerodynamic design of the basic aircraft will significantly increase the economy and safety of operation. A qualitative evaluation of the stability and control characteristics of the Piper PA-25B reveals adequate stability in all modes throughout the speed range of the aircraft. The inflight handling qualities were very good at normal operating speeds; however, the rudder force was considered excessive and the lateral control response was poor at airspeeds near the stall. The stall characteristics of the test airplane were normal for this type of aircraft; however, the aerodynamic stall warning was considered inadequate at maximum gross weight or in accelerated maneuver. Numerous aerodynamic measurements were made to determine the chordwise wing pressure distributions, the spanwise wing loading, the profile wing drag, the skin friction drag, the wing stall patterns, and the nature of the wing-tip vortex field behind the aircraft. Chemical distribution tests were run to determine the distribution characteristics of the solid material distributor. (Author)

Descriptors :   (*UTILITY AIRCRAFT, PERFORMANCE(ENGINEERING)), FLIGHT TESTING, AGRICULTURE, SPRAYS, SCATTERING, CLIMBING, AVIATION SAFETY, ECONOMICS, STALLING, LEADING EDGES, ROLL, AERODYNAMIC CHARACTERISTICS, DRAG, SKIN FRICTION, VORTICES, DISTRIBUTORS, DISTRIBUTION

Subject Categories : Transport Aircraft
      Agricultural Engineering

Distribution Statement : APPROVED FOR PUBLIC RELEASE