Beechcraft C-45 (military version of Beechcraft 18)
<a href="https://en.wikipedia.org/wiki/NMUSAF" class="extiw" title="w:NMUSAF">National Museum of the United States Air Force</a>
<a href="https://en.wikipedia.org/wiki/NMUSAF" class="extiw" title="w:NMUSAF">National Museum of the United States Air Force</a>