ADS-33 Evaluation of the International CH-47 Chinook

The DAFCS (Digital Automatic Flight Control System) equipped CH‐47 Chinook has been successfully deployed for the US Army and numerous international customers. Several of those international customers contracted with Boeing for ADS‐33 evaluations of the handling qualities of the aircraft including both the predicted and assigned (i.e. the Mission Task Elements) handling qualities. This paper covers the tailoring of ADS‐33 for the Chinook helicopter, the conduct of ADS‐33 testing and the results of the ADS‐33 testing. The primary focus of this paper will be centered on the Canadian long‐range CH147F ADS‐33 evaluation, which was a complete evaluation against all sections of ADS‐33 and was flown in 2012 and 2013. Additional lessons from two other standard‐range international customer evaluations, flown in 2013 and 2014 are also included. All of the configurations featured the DAFCS OFP 3.2 control laws, or a derivative thereof, which was originally developed for the US Army long range configuration. The section on the tailoring of ADS‐33 describes the process by which Boeing tailored ADS‐33E‐PRF for the Chinook and includes recommendations for future releases of ADS‐33. The assessment section describes the test techniques used and conduct of the testing, along with a summary of the results from both the predicted and assigned sections of ADS‐33.