01/31/2012. Remarks by Johan Visschedijk: "The Model 234, ordered by the USAAC as P-12E, was the first production model of the P-12/F4B series to use the new fuselage and tail surfaces of the Model 218. Other components were essentially those of the P-12D. A contract for 135 P-12Es was signed on March 3, 1931, and 110 (c/n 1460 to 1468, 1489 to 1533, 1535 to 1572; s/n 31-553 to 586, 32-1 to 32-76 were delivered as such between September 19 and October 15, 1931. The remaining 25 were converted to P-12F before completion.

As originally delivered, P-12Es and P-12Fs were painted with the standard Army olive drab fuselage and yellow wings and tail. The fuselage coloring was later changed to USAAC blue, and in 1940 the entire aeroplane was painted silver under an USAAC directive calling for all obsolescent tactical types having painted surfaces to be repainted in this color.

The basic P-12E underwent many changes of designation after entering service, as listed below, without change of the Boeing model number. The changes had little effect on overall performance.

The first P-12E (s/n 31-553 c/n 1460) was redesignated XP-12E on October 1, 1931. This did not distinguish it as the prototype P-12E, but merely identified a basic P-12E withdrawn from regular service for test work. After several other changes of designation (see below), 31-553 was reconverted to a standard P-12E.

P-12E 32-42 (c/n 1538) was redesignated P-12J when the standard 450 hp Pratt & Whitney SR-1340D engine was replaced by a 575 hp SR-1340H, and a special bomb sight were installed at Wright Field. This aeroplane became one of the seven YP-12Ks after still another engine change.

The XP-12E, P-12J, and five standard P-12Es (s/n 32-33, 32-26, 32-40, 32-46, and 32-49, c/n 1528, 1531, 1536, 1542 and 1545) became YP-12K when SR-1340E engines with fuel injection were installed for service test. All YP-12Ks were reverted to P-12E in June 1938.

YP-12K 31-553 (ex-XP-12E) was redesignated XP-12L on January 2, 1934, when fitted with a Type F-7 turbo-supercharger. It reverted to YP-12K in February 1937, and became P-12E with the rest of the YP-12Ks in June 1938.

The above pictured P-12E carries the 77th Fighter Squadron emblem on fuselage."