In December 1968, the Boeing Company defined a two-phase programme having the objective of demonstrating for the US Army those characteristics which experience with operation of the CH-47 Chinook had indicated would be required in the next generation of US Army transport helicopters. The programme, which was named the Model 347 Programme, would encompass simulation, wind tunnel, whirl tower, and bench testing and culminate with flight test development and demonstration of a modified CH-47A airframe. The first phase of the programme was aimed at establishing new standards for the flying qualities (handling, vibration and noise) of transport helicopters in a conventional pure helicopter arrangement. The second phase was to allow assessment of the value of providing a high manoeuvre capability for a transport helicopter as could be provided through the use of a fixed wing.