INVESTIGATION OF AN ISOLATED MONOCYCLIC V/STOL PROPELLER PERFORMANCE AND OSCILLATORY STRESS
Abstract
Test results confirmed: (1) that there is an apparent phase shift of the monocyclic axis at high collective angle, caused by hysteresis in the airfoil's stall characteristics, and (2) that there is an increase in side force as collective angle is increased, caused by a nonlinear variation in airfoil drag with cyclic pitch. The monocyclic propeller test program also included investigation of the effects of control system stiffness on the dynamic response of the propeller and control system. The results indicate that the use of cyclic-blade-pitch control reduces the harmonic content of control system oscillatory loads to basically a first-harmonic response. Higher harmonic loads are present, but their amplitudes are less than 10 percent of the resultant peak-to-peak load, and are therefore considered negligible. The results of the program also indicate that the increase of control system stiffness resulted in an increase in blade-pitch-link oscillatory loads.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 01, 1966
- Accession Number
- AD0629647
Entities
People
- R. W. De Decker
Organizations
- Boeing Rotorcraft Systems