Testing and evaluation of a stall-flutter-suppression system for helicopter rotors using individual-blade-control

Author:: Quackenbush, T. R.
Published:: Aug 1, 1981.
Physical Description:: 1 electronic document

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Summary:

The development and testing of a feedback system designed to alleviate the violent blade first torsion mode oscillations associated with stall flutter are described. The system, based on previously developed M.I.T. Individual-Blade-Control hardware, employs blade-mounted accelerometers to sense torsional oscillations and feeds back rate informaton to increase the damping of the first torsion mode. A linear model of the blade and control system dynamics is developed and is used to give qualitative and quantitative guidance in the design process as well as to aid in analysis of experimental results. System performance in wind tunnel tests, both in hover and forward flight, is described, and evidence is given of the system's ability to provide substantial additional damping to stall-induced blade oscillations.

Other Subject(s):

AIRCRAFT STABILITY AND CONTROL

Collection:

NASA Technical Reports Server (NTRS) Collection.

Note:

Document ID: 19810020597.
Accession ID: 81N29135.
NASA-CR-166233.
ASRL-TR-196-3.

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