Flight measurements of the vibration experienced by a tandem helicopter in transition, vortex-ring state, landing, approach, and yawed flight

John E. Yeates
SEP 1958

As part of a general program of helicopter vibration research, a flight investigation involving several flight maneuvers that are critical with respect to vibration has been conducted. The maneuvers include transition near the ground, landing approaches, vortex-ring state, and yawed forward flight.

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