Document Type: Technical Research Report. Purpose: Authoritative reference Authority: Government Civil Document Number: NACA Technical Note 3088, dated December 1953.

Scope: Preliminary NACA research report by Arthur Assadourian and John A. Harper of Langley Aeronautical Laboratory, Langley Field, Va.

Contents: From pages 1: "Summary: Flying qualities of the Douglas DC-3 airplane have been evaluated from a series of flight tests which were conducted to determine the longitudinal and lateral stability and control characteristics and stalling behavior of the airplane. Handling qualities are presented and compared with current Air Force-Navy handling-qualities specifications. Also included in the report for possible use by organizations using the DC-3 as a test vehicle for autopilots are some transient-response data from which some of the frequency-response characteristics of the airplane were determined.

Although the Douglas DC-3 airplane was designed before the formulation of any handling-qualities requirements, it satisfied most of the specifications for its type. Some of the characteristics which did not satisfy the requirements are as follows: The airplane was longitudinally unstable for certain conditions of airspeed and center-of-gravity position for the power-on configurations; the specified maximum elevator-control-force gradient in maneuvers in most cases was exceeded; the rudder forces required to overcome the adverse yaw in aileron rolls exceeded the allowable limit of 180 pounds; the rudder and aileron forces in steady sideslips tended to lighten at the higher angles of sideslip and the rudder forces actually reversed under some conditions. However, in spite of the few cases in which the airplane did not satisfy the requirements, the pilot thought that the airplane exhibited no serious flying-qualities deficiencies and handled well in normal flight."