This report presents a compilation of most of the zero-lift drag results obtained from free-flight measurements made by the Langley Pilotless Aircraft Research Division on fin-stabilized bodies of revolution. The data are arranged on standard forms, which also contain the significant geometrical factors. Supplementary data have been provided to facilitate the determination of the body pressure drags from the measurement total drags. Summary plots and discussions have been included to provide a unified and broad picture of the effects of the body geometry on zero-lift drag.

Two models each utilizing a scoop inlet located at the maximum-body-diameter station operating mass-flow ratios from 0.76 to 0.96 have been flight tested at an angle of attack of approximately zero degrees over a Mach number range from 0.8 to 1.8, and a Reynolds number range from 2,000,000 to7,000,000 based on body maximum diameter. One of the scoop inlets had a circular cross section with a boundary-layer diverter. The other scoop inlet had a semicircular cross section wrapped partly around the body with a boundary-layer splitter plate ahead of the inlet.

A flight investigation at subsonic speeds of a method to improve the damping of lateral oscillations by means of a viscous damping cylinder used in the rudder system in conjunction with adjusted hinge-moment parameters has been conducted. The damping device has been applied to a modern fighter-type jet-powered airplane. The rudder was made to float with the relative wind by the addition of trailing-edge strips. In order to amplify the floating tendency (by reducing the restoring moment), a highly geared balancing tab was incorporated. Lag of the motion of the free rudder with respect to the yawing of the airplane was introduced by means of a small viscous damping cylinder linked to the rudder.