Wind tunnel measurement of small values of rolling moment using six-component strain gauge balance

An experimental investigation was conducted to determine the accuracy of the rolling moment measurement in wind tunnel tests. The test was done in a high Reynolds number blowdown wind tunnel in subsonic, transonic and supersonic speed regimes. The rolling moment was measured on a missile model using an internal six-component monoblock strain gauge balance. The balance rolling moment element was designed as a five-bar cage measuring element. The expected rolling moment values in the test were significantly less than the balance rolling moment measuring element full scale. To check the accuracy of the balance measurement, a sensitive one-component transducer was designed and manufactured. In the first phase of the wind tunnel test, rolling moment was simultaneously measured using the balance and the sensitive transducer. Experimental data obtained using the balance was compared with those obtained by the transducer. It is shown that the balance data agree very well with the sensitive one-component transducer data.