Boeing F4B
The Boeing F4B was a single-seat biplane fighter built by Boeing for the U.S. Navy and Marine Corps, with a near-identical Army counterpart, the P-12. First flown in 1928 as a company private venture, the series became the primary fighter of both services in the early 1930s; total production of the F4B/P-12 series reached 586 aircraft. It was the last wooden-winged biplane fighter Boeing produced for the U.S. military. Front-line service ended in the late 1930s, second-line and training use ran into the early 1940s, and a handful of aircraft survive in museums.
Why It Mattered
The F4B/P-12 began as a Boeing private venture: Boeing began work on the design early in 1928, intending it to succeed the F2B and F3B in Navy service and the PW-9 with the Army. It became the primary fighter of both the U.S. Navy and the U.S. Army Air Corps in the early 1930s. It was the last wooden-winged biplane fighter produced by Boeing for the U.S. military, and the Navy's last Boeing biplane fighter. The two services bought the series in quantity — total production reached 586 — and the Smithsonian credits the orders with helping to establish Boeing as an important aircraft manufacturer and sustaining the firm through the Great Depression.
Design Notes
The two prototypes, Boeing's Model 83 and Model 89, were single-seat biplanes built in the standard way of their time: fabric over a bolted aluminium-tube fuselage frame and wooden wing frames. Power came from a Pratt & Whitney R-1340 Wasp radial engine. The F4B-1's armament was two .30-calibre machine guns synchronised to fire through the propeller arc, and it could carry five 24-lb bombs under each wing or a single 500-lb bomb beneath the fuselage. Development was stepwise: the F4B-2 brought a redesigned ring cowling and Frise ailerons, and its landing gear was improved with a split axle. The F4B-3 replaced the bolted alloy-tube fuselage with an all-metal semi-monocoque structure, while the wings — two-spar, fabric-covered, their control surfaces corrugated metal — were kept; the Army took the same version as the P-12E. The final version, the F4B-4, differed from the F4B-3 mainly in a broader-chord fin and a larger headrest, shaped to hold an inflatable life raft.
Operational History
The two XF4B-1 prototypes were first flown on 25 June 1928 and delivered to the Navy for evaluation. After extensive trials the Navy purchased twenty-seven production F4B-1s, and the first were delivered in the summer of 1929 to VB-1B aboard USS Lexington. The Army placed an order for ten similar aircraft with the carrier hook deleted and designated them P-12; Boeing supplied the Army Air Corps with 366 P-12s in all between 1929 and 1932. Army production followed the design's development: ninety P-12Bs, then a contract for 131 P-12Cs — the last thirty-five of the order identified as D models, identical to the C — and finally 135 of the semi-monocoque version, delivered as 110 P-12Es and twenty-five P-12Fs. Navy production ran in parallel: forty-six F4B-2s contracted in June 1930, twenty-one F4B-3s ordered in April 1931, and ninety-two F4B-4s, the last delivered on 28 February 1933, twenty-one of them assigned to the Marine Corps. P-12s were flown by the 17th Pursuit Group at March Field, California, and the 20th Pursuit Group at Barksdale Field, Louisiana, and older aircraft were used by groups overseas, including the 4th Composite Group in the Philippines. The Army's P-12 remained in first-line pursuit groups until replaced by Boeing P-26s in 1934–1935, and the F4B-4 remained in front-line service until 1938, when it was replaced by Grumman biplanes. Exports were small: Boeing exported twenty-three F4Bs to Brazil, and two aircraft were sent to Thailand. The series remained in service in numerous roles until the early 1940s; in 1941, twenty-three Army P-12s were transferred to the Navy and redesignated F4B-4A.
Afterlife
In the 21st century only a handful of surviving airframes remain, on display in museums. The Smithsonian's F4B-4 is one of the twenty-one built for the Marine Corps, bureau number 9241, donated to the institution in 1959; the museum currently lists the object as not on display, either on loan or in storage. It is now painted in its former colours as an aircraft of Marine Fighting Squadron VF-9M, with which it flew from Quantico until 1939. Other survivors include the civil Model 100 displayed at the Museum of Flight in Seattle and the Model 100E at the Royal Thai Air Force Museum in Bangkok, one of the two aircraft sent to Thailand. Not every display is an original: a three-quarter-scale replica F4B-4 stands in the entrance hall of Honolulu International Airport.