the sting plunging effect on measured pitch damping derivative

marija samardžić

Military Technical Institute, Belgrade, majasam@ptt.rs

zoran anastasijević

Military Technical Institute, Belgrade, anastaz@eunet.rs

DRAGAN MARINKOVSKI

Military Technical Institute, Belgrade

JOVAN ISAKOVIĆ

Military Technical Institute, Belgrade, jovanisakovic@gmail.com

DUŠAN ĆURČIĆ

Abstract: Stability derivatives measurements in the T-38 wind tunnel are based on the rigidly forced oscillation method. Large aerodynamic loads, which are generated on the model, cause sting deflection and oscillations. This paper presents method for determining the contribution of sting plunging to the moment derivative in small-amplitude pitch oscillations tests. Pitch damping derivative measurements of the Modified Basic Finner Model was performed at Mach numbers 0.6 and 1.75.  Results are obtained using new mathematical model for stability derivatives measurements. T-38 wind tunnel test results are compared with AEDC (USA) wind tunnel test results.