WIND-TUNNEL INVESTIGATION OF CONTROL-SURFACE CHARACTERISTICS XXI - MAXIMUM AND LARGE AERODYNAMIC BALANCES OF TWO NOSE SHAPES AND A PLAIN OVERHANG USED WITH A 0.40-AIRFOIL-CHOED FLAP ON AN NACA 0009 AIRFOIL

摘要

Wind-tunnel tests. have been made to investigate the characteristics of an NACA 0009 airfoil with a 40-percent-chord flap having medium and large aerodynamic balances of elliptical and blunt nose shapes and having a plain overhang. The results are presented as aerodynamic section characteristics for several flap deflections with the. gap at the flap nose sealed and unsealed. Tests were also made to determine the effectiveness of a tab, which was 20 percent of the flap chord, on the plain sealed flap and on the 35-percent-flap-chord elliptical-overhang flap with gap sealed. The pressure difference across the flap-nose seal was also determined for the plain sealed flap.