Accession Number:

ADA224493

Title:

Aerodynamic Performance of a 0.27-Scale Model of an AH-64 Helicopter with Baseline and Alternate Rotor Blade Sets

Descriptive Note:

Technical memo.

Corporate Author:

NATIONAL AERONAUTICS AND SPACE ADMINISTRATION CLEVELAND OH LEWIS RESEARCH CENTER

Personal Author(s):

Report Date:

1990-07-01

Pagination or Media Count:

23.0

Abstract:

Performance of a 0.27-scale rotor model designed for the AH-64 Apache helicopter alternate rotor was measured in hover and forward flight compared with an AH-64 baseline rotor model. Thrust, rotor tip Mach number, advance ratio, and ground proximity were varied. In hover, at a nominal thrust coefficient of 0.0064, the alternate rotor used about 6.4 less power than the baseline rotor. The corresponding thrust increase at this representative hover power condition was approximately 4.5, which represents an equivalent full-scale increase in lift capability of about 660 lb. Comparable results were noted in forward flight, except for the high-thrust, high-speed cases investigated Advance ratio 0.30, where the baseline rotor was slightly superior. Reduced performance at the higher thrusts and speeds was probably caused by Reynolds number effects and blade elasticity differences. edc

Subject Categories:

  • Aerodynamics
  • Military Aircraft Operations
  • Helicopters

Distribution Statement:

APPROVED FOR PUBLIC RELEASE