In this photograph taken in December 1917, a testing of an airplane engine is being conducted to determine the minimum and maximum horsepower. The photo showcases the propellers of the airplane in focus, highlighting the importance of engine testing during World War One. Released to the Subject Approval Signal Corps on December 27, 1927.

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Size: 9182px × 6304px
Photo credit: © piemags/NSC / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: ..., 27, 1917, 1927, activities, aero, airplane, american, construction, corps, dec., deo., engine, glasses, horse-, horse-power, military, photographs, propellers, sig., sun, testing, war, world