Leading edge retraction as a high lift device

• Main Author: Doss, Robert F.
• Format: Others
• Published: 1955
• Online Access: https://thesis.library.caltech.edu/4923/1/Doss_rf_1955.pdf; Doss, Robert F. (1955) Leading edge retraction as a high lift device. Engineer's thesis, California Institute of Technology. doi:10.7907/PV47-6A63. https://resolver.caltech.edu/CaltechETD:etd-12102003-110111 <https://resolver.caltech.edu/CaltechETD:etd-12102003-110111>

A two-dimensional investigation was carried out in the Merril Wind Tunnel at the California Institute of Technology to determine the effect on low speed lift of retracting the leading edge of a thin, circular-arc airfoil. Several configurations were tried, some with a spanwise slot milled into the upper surface so that the leading edge recess formed by retraction could be utilized as an air intake to improve the flow. A comparison was made between the configurations with the leading edge retracted to various positions and the basic airfoil. The investigation showed that leading edge retraction caused a linear loss of maximum lift proportional to the percent reduction in chord up to a critical position where lift and the stalling angle of attack increased abruptly. Thereafter, maximum lift was reduced at a rate higher than the chord reduction. The effect of the slot was negligible. The critical position phenomenon warrants further study.