Damage Mitigation for Rotorcraft through Load Alleviating Control

Open Access
Caudle, David Burdette
Graduate Program:
Aerospace Engineering
Master of Science
Document Type:
Master Thesis
Date of Defense:
December 10, 2014
Committee Members:
  • Joseph Francis Horn, Thesis Advisor
  • rotorcraft
  • helicopter
  • damage mitigation
  • control
  • load alleviation
A control method was developed to reduce the fatigue damage caused to critical rotorcraft hub components. This control method was demonstrated using simulation models of a utility helicopter similar to a UH-60 black Hawk and a large heavy-lift transport helicopter similar to a CH-53E Super Stallion. The components of interest were the pitch link, rotor shaft, and the stationary scissors. The component loads were related to vehicle states and limited within the control system. Batch and piloted simulations were conducted in the Penn State Flight Simulation Facility for both vehicles to evaluate the effectiveness of the damage mitigation control. The fatigue damage experienced by the critical components was shown to decrease during aggressive maneuvers at high airspeeds. Furthermore, implementing this control system caused only a slight degradation to the handling qualities.