FEASIBILITY TEST OF TRACTOR TAIL ROTOR MODIFICATION ON THE AH-1G HELICOPTER

A feasibility test of the tractor tail rotor modification of the AH- 1G helicopter was conducted near Fort Worth, Texas 550-feet elevation, and Alamosa, Colorado 7535-feet elevation, during the period 7 October to 19 October 1967. This test was conducted to obtain quantitative flight test data to serve as a basis for determining if the tractor tail rotor modification proposed by the contractor for the AH-1G helicopter would correct the directional control problems which currently exist on the AH-1G helicopter with the standard tail rotor configuration. This test revealed that in-ground-effect IGE low speed directional control and IGE low speed dynamic directional stability were greatly improved by installation of the tractor tail rotor,. IGE directional control limitations with the standard tail rotor installed were encountered at approximately 8100 pounds gross weight near sea level in previous tests. This test with the tractor tail rotor did not reveal any IGE directional control limitations at approximately 8940 pounds gross weight and near sea level. The test results indicate that additional directional control could be obtained with the tractor tail rotor, if the geometry of the directional control system were changed to negate the adverse effects of the stability and control augmentation system SCAS on the ability to obtain full left tail rotor pitch.