Evaluation of ADS-33E Cargo Helicopter Requirements Using a CH-53G

Flight tests with a Sikorsky CH 53G of the German Federal Armed Forces were conducted in Germany under the U.S./German Memorandum of Understanding (MoU) for Cooperative Research in Helicopter Aeromechanics to evaluate the cargo helicopter requirements of the U.S. Army Aeronautical Design Standard-33 (ADS-33E-PRF). The tests were carried out by the Wehrtechnische Dienststelle 61 (WTD 61, the German Armed Forces Technical and Airworthiness Center for Aircraft and Aeronautical Equipment), the German Aerospace Center (DLR), and the U.S. Army Aeroflighdynamics Directorate (AFDD). Quantitative data for hover and 100 knot forward flight were gathered. Five test pilots flew the Mission Task Elements in good visual environment and gave handling qualities ratings for thirteen Mission Task Elements as listed in ADS-33E-PRF, including the evaluation of handling qualities with an external slung load. The objective of this test was to evaluate the applicability of the ADS-33E-PRF cargo helicopter requirements using a helicopter with conventional main and tail-rotor configuration. Assessing the related handling qualities of the CH-53G is the means to do so, not the objective. This paper describes the test set-up, the main pilot comments and handling qualities ratings, and the initial results and lessons learned with respect to ADS 33E PRF.