Accession Number : AD0018819


Title :   FURTHER CORRELATION OF OBSERVED AND THEORETICAL HELICOPTER DYNAMIC LONGITUDINAL RESPONSE CHARACTERISTICS


Corporate Author : PRINCETON UNIV NJ


Personal Author(s) : SECKEL, EDWARD


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/018819.pdf


Report Date : 31 Mar 1953


Pagination or Media Count : 63


Abstract : The correlation of longitudinal dynamic response data with theoretical predictions was considered. A satisfactory correlation was obtained with either fairly complete equations of motion or greatly simplified ones. With the proper values of lift, drag, moment, and total derivatives, the equations of motion were considered capable of predicting with satisfactory accuracy the responses observed in flight testing. However, existing theories were generally inadequate for predicting the proper values of the important derivatives. The simplified equations were considered adequate for the slower modes of motion because the errors introduced by the simplifying assumptions were overshadowed by the inaccuracy of estimating the more important derivatives. These equations also predicted with reasonable accuracy frequency-response information derived from test data. The effects of nonstandard bar damper settings were not satisfactorily explained; these were assumed to be associated with damper nonlinearities.


Descriptors :   *FLIGHT TESTING , PITCH(MOTION) , EQUATIONS OF MOTION , PREDICTIONS , DYNAMIC RESPONSE , THEORY , DAMPING , MOTION , ACCURACY , NONLINEAR SYSTEMS , INFLIGHT , VALUE , EQUATIONS , DRAG , LIFT , SIMPLIFICATION , EXPERIMENTAL DATA


Subject Categories : Guided Missile Traj, Accuracy and Ballistics


Distribution Statement : APPROVED FOR PUBLIC RELEASE