critical engine

critical engine

The engine whose failure would cause the most adverse effect on the performance and handling qualities of the aircraft. It is that engine whose loss would result in the maximum disadvantage because of asymmetrical effects or result in other adverse effects.
critical frequency
i. The frequency at which a critical angle becomes zero. The highest frequency at which vertical reflection is possible.
ii. The frequency corresponding to the resonance frequency of a blade, control surface, or other vibrating or moving structure.
iii. The frequency of a helicopter main-rotor-blade passing at which the whole helicopter resonates on the landing gear.

An Illustrated Dictionary of Aviation Copyright © 2005 by The McGraw-Hill Companies, Inc. All rights reserved