Abstract: In order to reduce the effects of free spin test system on the test results in the vertical wind-tunnel,a remote control system to pilot the model's control surfaces was developed.The model suspension system was optimized and the effects of suspension components on the spin results were studied.It is shown that the remote control system is able to pilot the control surface independently or assembly,it meets the requirements of spin test.The results show that it has certain effects for the weights and shapes of the suspension system components on rotating speed while little effects on the spin angles of attack,the methods and turns of spin recovery.