One of the
most famous of Boeing's biplane fighters of the inter-war years, the F4B originated as a private venture to develop a replacement for the US Navy's F2B/F3B carrier-based fighters, which had first entered service in 1928. Although they had only been in service for a very short period, Boeing believed it was possible to refine the design to give improved performance without additional power.
Two very similar prototypes were built: Boeing Models 83 and 89. The former had a spreader-bar axle landing gear and an arrester hook; the latter a split-axle landing gear so that a bomb could be carried beneath the fuselage. In other respects they were virtually identical. Following Navy evaluation in the summer of 1928, 27 were ordered as F4B-1, these combining the split-axle landing gear, bomb carrying provisions and arrester hook. Forty-six F4B-2, delivered in early 1931, had the spreader-bar axle, a tailwheel, Frise ailerons and a neat ring cowling for the engine. They were followed by 21 F4B-3 with a semi-monocoque metal fuselage and 92 F4B-4 which differed by having a larger fin and rudder.
The USAAC ordered ten aircraft similar to the F4B-1 in late 1928, accepting the naval evaluation as being correct. Designated P-12, these differed only by having the arrester hook and other specifically naval equipment deleted. P-12B, of which 90 were built with 317kW Wasp engines, differed very slightly and were followed by 96 P-12C, which were similar to the Navy's F4B-2. P-12D, of which 35 were built, had a more powerful 391kW Wasp engine. Most extensively built of the Army versions was the P-12E. This had a monocoque fuselage, pilot's headrest faired by a turtleback and the more powerful engine of the P-12D. A total of 135 were ordered in 1931, many remaining in service until replaced by P-26A in 1935. The last few of the order were given 447kW Pratt & Whitney R-1340-19 engines and the designation P-12F.
Total production for the Army and Navy amounted to 586 aircraft representing a production record for a basic military design which remained unequalled until the attainment of long production runs during World War II.
