The assembly plant of the Bell Aircraft Corporation at Wheatfield, New York (directly East of Niagara Falls, USA). The aircraft in the photo are Bell P-39Q-30-BE Airacobra fighters (USAAF serials 44-71105/44-71504), and Bell P-63A-8-BE Kingcobra fighters (USAAF serials 42-69211/42-69410). While externally very similar, the P-39 had a smaller and more rounded tail section and a three-bladed propeller. The two lines at left are P-39Qs, followed by three lines of P-63As. Then are two lines of almost completed P-39Qs (serials clearly visible), and a last line of P-63As. Note the absence of any workers and tools. This work is in the public domain in the United States because it is a work prepared by an officer or employee of the United States Government as part of that person’s official duties under the terms of Title 17, Chapter 1, Section 105 of the US Code. Source: Wikipedia, in public domain.
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