FLIGHT-TEST INVESTIGATION ON THE LANGLEY CONTROL-LINE FACILITY OF A MODEL OF A PROPELLER-DRIVEN TAIL-SITTER-TYPE VERTICAL-TAKE-OFF AIRPLANE WITH DELTA WING DURING RAPID TRANSITIONS

摘要

A flight-test investigation has been made on the Langley control-line facility to determine the longitudinal stability and control characteristics of a model of a propeller-driven tail-sitter-type vertical-take-off airplane with delta wing during rapid transitions from hovering flight to forward flight and back to hovering. The control-line facility provides for the flying of models in a large-diameter circle by means of a control-line technique similar to that used by model-airplane enthu¬siasts. The present investigation showed that the facility was generally satisfactory for investigating the characteristics of vertical-take-off models during rapid transitions. It was found that rapid transitions from hovering flight to forward flight could be performed fairly easily, but precise longitudinal control was necessary to perform the transitions smoothly. The transitions from forward flight to hovering flight were more difficult to perform because there was a greater variation of power settings which require closer coordination of the power and pitch control.