In this paper we report preliminary results of investigations into the nature of ultrasonic wave propagation and resulting surface displacements in two selected fiber reinforced composite materials: aluminum with boron fiber reinforcement and Lucite with steel rod reinforcement. These materials have reinforcing fiber diameters that are small and large respectively when compared with the propagating ultrasonic wavelengths. The ultrasonic waves are observed by detecting surface displacements using a scanning micro-interferometer designed for this purpose and discussed in detail elsewhere.