Abstract: The issue of single snapshot airspeed estimation is researched based on acoustic sensor array. According to the propagation property of acoustic waves in subsonic and supersonic air current, the output model of acoustic sensor array is constructed for a given measuring equipment. Then an airspeed estimation algorithm based on Sparse Covariance Matrix Iteration with a Single Snapshot (SCMISS) is presented. SCMISS has several unique features not shared by other sparse estimation methods: it does not require the user to make any difficult selection of regularization parameters, and it has lower computational complexity and better real-time. What is more, the proposed algorithm can be applied to both subsonic and supersonic circumstances with single snapshot measurement. Finally, a compact expression for the Cramr-Rao Bound (CRB) on the estimation error of airspeed is derived to evaluate the performance of the proposed algorithm. Simulations are implemented to show the effectiveness of SCMISS.