WorldCat Identities

Berry, John D.

Works: 3 works in 15 publications in 1 language and 568 library holdings
Roles: Author
Classifications: TL716,
Publication Timeline
Most widely held works by John D Berry
Description of the U.S. Army small-scale 2-meter rotor test system by Arthur E Phelps( Book )

6 editions published in 1987 in English and held by 135 WorldCat member libraries worldwide

A small scale powered rotor model was designed for use as a research tool in the exploratory testing of rotors and helicopter models. The model, which consists of a 29 hp rotor drive system, a four blade fully articulated rotor, and a fuselage, was designed to be simple to operate and maintain in wind tunnels of moderate size and complexity. Two six-component strain-gauge balances are used to provide independent measurement of the rotor and fuselage aerodynamic loads. Commercially available standardized hardware and equipment were used to the maximum extent possible, and specialized parts were design so that they could be fabricated by normal methods without using highly specialized tooling. The model was used in a hover test of three rotors having different planforms and in a forward flight investigation of a 21 percent scale model of a U.S. Army scout helicopter equipped with a mast mounted sight. Keywords: Rotor model; Hover testing; Rotor scaling
Unsteady velocity measurements taken behind a model helicopter rotor hub in forward flight by John D Berry( Book )

4 editions published in 1997 in English and held by 121 WorldCat member libraries worldwide

Wind-tunnel evaluation of a 21-percent-scale powered model of a prototype advanced scout helicopter by Arthur E Phelps( Book )

5 editions published in 1985 in English and held by 95 WorldCat member libraries worldwide

This exploratory wind-tunnel investigation was conducted in the Langley 4- by 7- Meter Tunnel. The investigation was conducted to define the overall aerodynamic characteristics of the Army Helicopter Improvement Program (AHIP), to determine the effects of the rotor on the aerodynamic characteristics, and to evaluate the effect of a mast-mounted sight on the aircraft stability characteristics. Tests covered a range of thrust coefficients, advance ratios, angles of attack, and angles of sideslip and were run for both rotor-on and rotor-off configurations. Results of the investigation showed that the prototype configuration was longitudinally unstable with angle of attack for all configurations tested. The instability was due to unfavorable interference effects between the horizontal tail and the wake shed from the engine pylon and rotor hub, which caused a loss of horizontal-tail effectiveness. The addition of the mast-mounted sight had little effect on the stability of the model, but it caused an alteration in the rotor lift distribution that resulted in substantial interference drag for the sight. Keywords: Scout helicopter; Mast-mounted sight; Powered rotor testing; Rotor interference effects
Audience Level
Audience Level
  Kids General Special  
Audience level: 0.57 (from 0.51 for Unsteady v ... to 0.61 for Wind-tunne ...)

English (15)