 Power was to have been provided by the eight-cylinder, water-cooled 330 hp Wright K-2 engine but the first two prototypes were fitted with 346 hp Packard 1A-1116 units due to delays in clearing the K-2 for flight testing.A third prototype was also built and testing was eventually carried out using both the K-2 and Packard 1A-1237 at McCook Field.Prototype aircraft suffered disappointing performance, high levels of vibration and poor visibility.