This Northrop Alpha fast transport made a brief visit to the Langley Memorial Aeronautical Laboratory in February 1931. One of Jack Northrop's earlier designs, it resembled some of the Lockheed products of the time which Northrop had helped design before starting his own firm.
<a rel="nofollow" class="external autonumber" href="https://archive.org/details/NIX-EL-1999-00366">[1]</a>