Pilot James Christensen waits

Douglas M-1, 1926-Lederer

Liberty engine on test stand

Pilot E. Hamilton Lee 1920,

Checkerboard Field 1920 

Gassing up JND-4H

Day flying equipment

Field superintendents, 1924 

Junkers JL-6, 1921

Boeing Air Transport pilots

National Air Transport pilots

National Air Transport pilots

Beacon at emergency field

Pilot Shirley Short -- Colyer trophy won by Service

Twin City-Chicago, 1920

First flight Minneapolis, 1920

First eastbound, 1920

First flight Minneapolis