Download or read book Comparison of Pitching Moments Produced by Plain Flaps and by Spoilers and Some Aerodynamic Characteristics of an NACA 23012 Airfoil with Various Types of Aileron written by Paul E. Purser and published by . This book was released on 1945 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: An analysis and comparison has been made of the pitching moment characteristics of airfoils with plain flaps and spoilers. Sectional characteristics of airfoil having retractable slotted flap with plain, slot-lip, or retractable ailerons are presented for a large range of aileron deflections. The analysis indicated that pitching moments produced by spoilers were less positive than those produced by plain flaps of equal effectiveness, also that pitching moments created by the spoiler increased less with the Mach number than similar moments produced by plain flaps. Positive values of pitching moment decreased as devices were located nearer airfoil leading edge.