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Wind-Tunnel Investigation of Control-Surface Characteristics XX : Plain and Balanced Flaps on an NACA 0009 Rectangular Semispan Tail Surface

Description: Correlation is established between aerodynamic characteristics of control surfaces in two-dimensional and three-dimensional flow. Slope of lift curve was affected little by overhang and balance-nose shape, but increased by sealing flap-nose gap. Effectiveness of balancing tab was same for sealed plain flap and unsealed overhang flap. Changes in hinge-moment coefficient were diminished by sealing gap. Values measured by three-dimensional flow disagreed with two-dimensional flow values until aspect ratio corrections were made.
Date: October 1, 1944
Creator: Garner, Elizabeth I.
Partner: UNT Libraries Government Documents Department

Wind-Tunnel Investigation of Perforated Split Flaps for Use as Dive Brakes on a Tapered NACA 23012 Airfoil

Description: Aerodynamic characteristics of a tapered NACA 23012 airfoil with single and double perforated split flaps have been determined in the NACA 7- by 10-foot wind tunnel. Dynamic pressure surveys were made behind the airfoil at the approximate location of the tail in order to determine the extent and location of the wake for several of the flap arrangements. In addition, computations have been made of an application of perforated double split flaps for use as fighter brakes. The results indicated that single or double perforated split flaps may be used to obtain satisfactory dive control without undue buffeting effects and that single or double perforated split flaps may also be used as fighter brakes. The perforated split flaps had approximately the same effects on the aerodynamic and wake characteristics of the tapered airfoil as on a comparable rectangular airfoil.
Date: November 1, 1941
Creator: Purser, Paul E. & Turner, Thomas R.
Partner: UNT Libraries Government Documents Department