Accession Number:

AD0671079

Title:

EVALUATION OF THE CALLAIR A-9 AGRICULTURAL AIRCRAFT

Descriptive Note:

Technical rept.

Corporate Author:

MISSISSIPPI STATE UNIV MISSISSIPPI STATE DEPT OF AEROPHYSICS

Personal Author(s):

Report Date:

1966-11-01

Pagination or Media Count:

76.0

Abstract:

The aircraft was evaluated in three configurations 1 clean or basic aircraft, 2 basic aircraft with solid material distributor attached, and 3 basic aircraft with spray dispersal equipment 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 operations. The results of this investigation indicate that the aerodynamic 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 CallAir A-9 revealed that the aircraft had adequate lateral-directional stability, but that the static longitudinal stability was marginal. The inflight handling qualities at normal operating speeds were very good and the rudder forces were especially light. The large leading edge radius of the wing resulted in very low stall speeds and mild stall characteristics in unaccelerated flight. In accelerated climbing turns, the aircraft exhibited a tendency to roll unusually rapidly toward the outside wing even though it was shown that the airflow was attached over the ailerons. 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 conducted to determine the distribution characteristics of the solid material distributor.

Subject Categories:

  • Transport Aircraft
  • Agricultural Engineering

Distribution Statement:

APPROVED FOR PUBLIC RELEASE