A computer model is described that can generate the Point Spread Function (PSF) for a multiaperture optical system. The model basically does a Fourier transform of the multipupil wavefront to propagate the wave front to the far field. In our model the PSF is synthesized in the far field by squaring the net complex field resulting from the individual relative phase shifts. The wavefront for each subaperture can be expanded in terms of Zernike polynomials. Arbitrary amounts of aberration can be assigned to each individual array telescope. Using the program we did a Monte-Carlo wavefront error analysis that demonstrated general correspondence between RMS wavefront error and encircled energy. The effects of piston on beam steering and shaping are presented.