ABSTRACT A simple, inexpensive, continuous-application rainfall simulator was developed using air injected into a water conduit. The effect of injecting air was to maintain higher discharge pressures enabling better uniformity without increasing the rainfall intensity. The air/water mixture and discharge pressure were varied to control intensity and drop size. Intensities ranging from 76 to 168 mm/h with a minimum distribution uniformity of 84 percent were produced; and drops were produced with size, velocity, and impact angles approximating natural rainfall. The simulator was designed for an effective area of 6 m x 6 m but can easily be modified