Army Preliminary Evaluation 3 and 4, YCH-47C Medium Transport Helicopter

Abstract

Army Preliminary Evaluation (APE) consisted of vibration noise level tests and a re-evaluation of the stability and control characteristics modified by the incorporation of engineering changes to correct the handling qualities deficiencies found during APE II. APE IV was a re-evaluation of the vibration characteristics which was required because of structural modifications incorporated in the aircraft following APE III. The helicopter showed significant improvements in trimmability, static and dynamic longitudinal stability and lateral-directional stability as compared to aircraft flown during APE I and II. The longitudinal stability improvements permitted sustained hands off flight. The vibration levels experienced during APE IV were improved over APE III. The aircraft met all requirements except two of the detail specification and two of the military specification.

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Document Details

Document Type
Technical Report
Publication Date
Oct 01, 1970
Accession Number
AD0878571

Entities

People

  • Jerry L. Jester
  • Robert F. Forsyth

Organizations

  • Edwards Air Force Base

Tags

Communities of Interest

  • Air Platforms
  • Weapons Technologies

DTIC Thesaurus Topics

  • Air Temperature
  • Aircrafts
  • Airspeed
  • Auxiliary Power Units
  • Control Rods
  • Control Systems
  • Engineering
  • Engines
  • Flight Control Systems
  • Flight Speeds
  • Fuel Systems
  • Helicopters
  • Instrumentation
  • Production
  • Test And Evaluation
  • Thrust Control
  • United States

Readers

  • Aerospace Engineering
  • Software Engineering