Army Preliminary Evaluation 3 and 4, YCH-47C Medium Transport Helicopter
Final rept. Jun 1966-Oct 1969
ARMY AVIATION SYSTEMS TEST ACTIVITY EDWARDS AFB CA
Pagination or Media Count:
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.
- Transport Aircraft