Polish P type single-seat fighters : all-metal gull-type wing monoplanes (1931)
NASA Technical Reports Server (NTRS) · leaf 15
N.A.C.A. Aircraft Circular llo. 137 Figs. 9,10 Fig. 9 Exceptional view obtained ''oy the special design of the center section and rring. (Taken from Engineering, July 1930.) … Fig. 10
NASA Technical Reports Server (NTRS)
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