Accession Number:

ADA270663

Title:

Blade and Hub Loads of Ballistically Damaged Helicopter Rotors

Descriptive Note:

Final rept. Apr 92-May 93,

Corporate Author:

ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD

Personal Author(s):

Report Date:

1993-10-01

Pagination or Media Count:

50.0

Abstract:

The effects of simulated ballistic damage on helicopter rotor blade response and rotor hub loads are investigated. A finite element formulation based on Hamiltons principle is used for structural analysis, and aerodynamic loads are calculated using quasisteady aerodynamic theory. Each blade is as being composed of elastic beams undergoing flap bending, lag bending, elastic twist, and axial deflections. Dynamic responses of multi-blade rotor systems are calculated from nonlinear periodic normal mode equations using a finite element in time scheme. Results are calculated for the SA3492 Gazelle helicopter for both undamaged and damaged blade configurations. Blade damage effects are determined in terms of blade mode shapes and frequencies, aeroelastic response, and rotor hub loads. Blade dissimilarity due to ballistic damage can induce a large 1rev vibratory component on the rotor hub.

Subject Categories:

  • Aerodynamics
  • Helicopters

Distribution Statement:

APPROVED FOR PUBLIC RELEASE