Abstract: The boundary layer equations in a noninertial curvilinear coordinate system are derived using the technique of asymptotic expansion. As the pressure terms are eliminated from the first order boundary layer equations, only one Coriolis force term appears in the x 1 and x 2 momentum equations (they are due to the local normal component of the angular velocity of the moving body), while other inertial force terms do not enter the first order boundary layer equations

Key words: unsteady flow, boundary layer equations, spherical coor dinates