The Franklin 12 series of 12-cylinder air-cooled horizontally opposed aircraft engines produced in the 1940s and 50s, (US military designation O-805 was applied to the 12AC-806, 12ACG-806 and 12ACGSA-806).
The Franklin O-805 was to be used in radio-controlled pilotless drones that were to be guided from an accompanying control plane. Due to project requirement changes and cancellations the engine was not produced.
Apparently the engine had no civil application and only a limited military use, as the O-805 in Interstate XBQ-5/XTD2R.
The Franklin O-335 (Company designations variations on 6A4) was a series of air-cooled aircraft engines of flat-six configuration.
These engines were commonly vertically mounted and used to power many early helicopters in the United States. They were closely related to the 2A4 and 4A4 2- and 4-cylinder engines. In various subtypes, the 6A4 remained in continuous production from 1945 to the time Franklin’s United States operations ceased in 1975, with versions continuing in Polish production into the 1990s. 6AC ATC 222, 225
In 1947 this engine was modified into a water-cooled version by the Tucker Car Corporation for use in the 1948 Tucker Sedan. Tucker liked the engine so much that he purchased the Aircooled Motors/Franklin Engine Company and it remained under the ownership of the Tucker family until 1961.
Variants:
O-335 Military designation
6A4-124 6 cyl 334ci
6A4-130 6 cyl 334ci
6A4-135 6 cyl 334ci
6A4-140 6 cyl 334ci
6A4-145 6 cyl 334ci
6A4-150 6 cyl 334ci
6A4-165 6 cyl 334ci
6A4-178 6 cyl 334ci
6A4-1854 6 cyl 334ci
6A4-200 6 cyl 334ci
6A4-300 6 cyl 334ci
O-335 6 cyl 334ci
6A-335 180 hp (134.2 kW) at 2,800rpm, 200 hp@3100 rpm 1963-1976
The Franklin 4 (US military designations O-150, O-170, O-175, O-200, O-225 and O-235) was a series of air-cooled aircraft engines of flat-4 configuration produced in the 1930s and 40s. The 4AC was first run in 1938.
4AC-199-B – 65 hp (48 kW) at 1,950 rpm 4AC-199-D – 85 hp (63 kW) at 2,500 rpm 4AC-199-E (O-200-1) – 90 hp (67 kW) at 2,500 rpm 4AC-199-H (O-200-5) – 113 hp (84 kW) at 3,500 rpm
In 1929 Jos P. Bauer designed the Model A tandem-seat biplane (55hp Velie). This led to Franklin Aircraft, at Franklin, PA. Nine Model A were followed by a Model B.
Jimmy Franklin first conceived it, built it, and then flew it. He first debuted the Jet Waco in 1999, and quickly made it one of the air show world’s most popular acts of all time.
The Franklin 1937 UPF-7 Waco bi¬plane that has a conventional radial engine and a 2200-lb-thrust jet unit from a Cessna Citation bolted between the main gear. Warm the Pratt & Whitney R-985 piston engine up well, test the smoke system a few times for good crowd effect, pretend to take off in the normal fashion by pointing the nose into wind up the runway, then give it the gas: full noise but across the runway and straight up. Jimmy Franklin put his Waco into a routine of loops and rolls, with son Kyle Franklin as wing walker, in pure jaw dropping entertainment. With over 4,500 lbs of thrust and 2,000 horsepower, Jimmy performed stunts that no one has ever attempted in this type of aeroplane.
