Sweepback Angle Research Articles

Some Structural Parameters for an Aero‐Isoclinic Wing

The general theory of the clastic behaviour of a conventional single‐cell wing stiffened with swept ribs (or stringers) has been dcvclopcd. It was shown that the swept members introduce a measure of skewness in the structural geometry of the wing which cause the wing to twist, as well as bend, under simple bending loads. This note shows that, if the sweepback angle is not more than 35 deg., it is possible to make a wing aero‐isoclinic by introducing swept stringers.

Harmonic and Transient Motion of a Swept Wing in Supersonic Flow

The results of previous papers on the harmonic 1 , 3 and transient motion and loading of two-dimensional airfoils in supersonic flow are extended to include the infinite swept airfoil, provided tha t the component of flow normal to the leading edge remains supersonic. I t is shown tha t the various normal force derivatives are reduced by the cosine of the sweepback angle and tha t the effective Mach Number corresponds to the component of flow normal to the leading edge. This result is related to the invariance of the magnitude of the circulation under sweepback and Busemann's rule with respect to compressibility effects. The flutter of a swept wing is considered, and it is pointed out tha t sweepback introduces additional aerodynamic coupling between torsion and bending. The flutter of a supersonic swept wing with subsonic leading edge is discussed, and an approximate treatment is suggested.