All Aero

One prototype SM-3 was built in 1927 for retractable gear tests. A four-place cabin low-wing monoplane, the SM-3 featured a tapered, strut-braced gullwing, and was powered by a 220hp Wright J-5C engine. Flown in one test by Eddie Stinson, who likened its flight characteristics to “a brick” and cancelled the project in 1928.