Trivia Series #7, Question #10

This aircraft was intended for use as a passenger or cargo aircraft, and a total of 23 were built. It was available several configurations. It served as both a commercial and military transport. The first was built in 1930 and was capable of carrying 12 to 15 passengers. The next model was powered by a larger, more reliable engine; one version came with available floats. Other versions included a deluxe model, with custom interiors available and seating for nine. The final model was the most efficient airplane of its day and even would rank high among all airplanes ever designed. With the proper engine, it could carry a useful load greater than its empty weight. In 1934, US federal regulations changed, virtually eliminating future markets for this aircraft. One flyable aircraft still exists in a museum, and another is undergoing restoration.

Name this aircraft. Answer by PM only. Do not answer " Was It " or with a question mark. No changing of an answer after your original submission. Any answer submitted after 1200 hrs E.S.T on the day the answer will post will not count. Answer will post on 04/15/07 at 1200 hrs E.D.T.

In the likely event of a tie, a series of tie breakers will be posted for the winners only, not to exceed three questions. If this results in a continued tie, co-winners will be declared.