The intent of this paper is to investigate the effectiveness of direct nume
rical computation in capturing acoustic fields. It has been the trend to us
e high-order schemes whenever there is interest in resolving the acoustic f
ield, even though there has never been a complete study of the accuracy of
low-order schemes. We revisit a long-standing benchmark problem in aeroacou
stics to show the validity of such low-older schemes. The problem we consid
er is that of a flat-plate airfoil in a non-uniform flow. We show that when
the linearized Euler equations are used to model problems in aeroacoustics
, a simple second-order numerical scheme is powerful enough to provide accu
rate aeroacoustic results. We validate this computational approach by compa
ring both the RMS and instantaneous pressure on the airfoil and in the far
held to semianalytic and asymptotic results.