Flightline: 157 - Bell D-188/XF-109/XF3L-1
The result of a joint USAF/USN request for a supersonic V/STOL fighter-bomber, the D-188A was canceled before progressing beyond a single mockup.
The genesis of the plane, known internally as Bell Model 2000, was in a 1955 joint request by the Air Force and Navy for a new V/STOL aircraft capable of Mach 2, which would act as a fighter-bomber for the USAF and a fleet defense interceptor for the Navy. The design was highly ambitious and unconventional, with a long fuselage mated to high, short wings that terminated in rotating nacelles holding two engines each. The aircraft would have six or eight J85 engines total depending on the model, four on the wings, two in the tail, and two more optionally in the forward fuselage for vertical thrust. The Navy model would also incorporate a bleed air system to enhance vertical lift and maneuvering.
Cutaway drawing of the six-engined D-188A variant. | Illustration: Bell Aircraft
A more simplified drawing of the eight-engined variant, showing the forward pair of lift jets and the vectoring of the aft nozzles for vertical or horizontal flight. | Illustration: Bell Aircraft
Armaments would have consisted of two or four 20mm cannons as well as an internal weapons bay and provisions for hardpoints on the wings for missiles, rockets or bombs, up to 4,000lbs total. Unrefueled combat range would have been 1,350 miles, with a ferry range of 2,300 miles.
Photo collage of the the D-188A mockup and concept art. | Illustration: Bell Aircraft
DOD plans in 1958 called for three prototypes of the aircraft, given the tentative designation XF-109 by the USAF and XF3L for the Navy to be completed in 1960, and for production of the aircraft starting in 1962.
Concept art of the XF-109 in hover. | Illustration: Bell Aircraft
Bell artwork of a XF-109 undergoing (simplified) maintenance. Taking care of eight jet engines would have been challenging, especially under austere conditions. | Illustration: Bell Aircraft
Orthograph of the XF-109 in the 1960 configuration. | Illustration: G. De Chiara
Illustration of the XF3L showing the subtle differences in the empennage. | Illustration: G. De Chiara
The mockup was completed in December 1960, and was displayed in both USAF and Navy markings. By this point however, interest in the program had cooled, with first the Navy then the USAF dropping out by 1961. It's unlikely that the plane would have met the somewhat (okay, very) unrealistic performance goals as stated, so an operational D-188/A would likely have been slower, had less range, and/or carried less of a payload.
The D-188A mockup in US Navy markings and with the engine pods in VTOL position. | Photo: Bell Aircraft
The D-188A in XF-109 markings. | Photo: Bell Aircraft
The XF-109/XF3L mockup was a intriguing look at a future that was not to be. | Photo: Bell Aircraft