Accession Number : AD0778823

Title :   An Analysis of Fixed Wing-Proprotor Interference for Folding Proprotor Aircraft.

Descriptive Note : Technical rept., Aug 1971-1973,

Corporate Author : BELL HELICOPTER CO FORT WORTH TEX

Personal Author(s) : Matthys,Carl G. ; Joglekar,Mukund M. ; Ksieh,P. Y.

Report Date : MAR 1973

Pagination or Media Count : 319

Abstract : The report describes the development and implementation of an analysis of the mutual aerodynamic interference of the wing and the proprotor on a folding proprotor aircraft. The analysis was developed to complement and expand the capabilities of an existing AFFDL stability and control prediction method for helicopters and stoppable rotor aircraft. The wing-rotor interference section was added to the AFFDL program as an option to the user. This report is divided into four parts. The first part describes the formulation of a math model and its capabilities. The flight mode response of a typical folding proprotor aircraft during rotor feathering is discussed. The second part explains usage of a computer program implementing the math mode. Sample cases are presented as well as a description of the input and output formats. The third part contains a cross reference index of FORTRAN variables and subroutine names. The fourth part is a complete FORTRAN listing of the AFFDL program modified to include the interference subroutine. (Author)

Descriptors :   *SHORT TAKEOFF AIRCRAFT, *FOLDING HELICOPTER ROTORS, FORTRAN, AERODYNAMIC STABILITY, EQUATIONS OF MOTION, INTERFERENCE, AIRFOILS, AERODYNAMICS, COMPUTER PROGRAMS

Subject Categories : Aerodynamics
      Helicopters
      V/STOL

Distribution Statement : APPROVED FOR PUBLIC RELEASE