The Franklin 6A4 (US military designation O-335) was a series of air-cooled aircraft engines of flat-6 configuration. These engines were commonly vertically-mounted and used to power many early helicopters in the US. 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 US operations ceased in 1975, with versions continuing in Polish production into the 1990s. The Franklin Engine Company was a manufacturer of aircraft engines. ... The flat-6 engine of the Honda Valkyrie motorcycle A flat-6 is a 6 cylinder configuration of a flat engine or boxer engine. ... This is a list of aviation-related events from 1945: // Events January January 1 - the Luftwaffe begins targeting Allied airfields in Europe as Operation Bodenplatte February February 13-15 - Allied bombers attack Dresden with incendiary weapons, destroying most of the city and killing some 50,000 people. ... This is a list of aviation-related events from 1975: Events January A specially modified McDonnell Douglas F-15 Eagle sets eight time to climb records, including one of 3 minutes 27 seconds from standstill on the runway to a height of 30,000 metres (98,425 feet). ...

Applications

• Aero-Flight Streak
• Aeronca Sedan
• Bartlett Zephyr
• Bell 47
• Bellanca Cruisair
• Goodyear Duck
• H-23 Raven
• Hiller 360
• Seibel S-4
• Sikorsky S-52
• Stinson Voyager
• Taylorcraft 15
• Temco TE-1B
• YT-35 Buckaroo

The Aeronca 15AC Sedan is a four-seat fixed conventional gear general aviation airplane which was produced in the United States between 1948 and 1951. ... Bell 47G Bell 47J Bell 47G in M*A*S*H paint scheme. ... The Bellanca Aircruiser was a high wing, single engine aircraft built by Bellanca Aircraft Corporation of New Castle, Delaware. ... OH-23 The four-place Hiller H-23 Raven light observation helicopter was based on the United States Navy UH-12, which was first flown in 1948. ... OH-23 The four-place Hiller H-23 Raven light observation helicopter was based on the United States Navy UH-12, which was first flown in 1948. ...

Specifications (6A4-165)

General characteristics

• Type: 6-cylinder air-cooled horizontally opposed aircraft piston engine
• Bore: 4.5 in (114 mm)
• Stroke: 3.5 in (89 mm)
• Displacement: 334 in³ (5.5 L)
• Dry weight: 291 lb (132 kg)

Components

• Cooling system: Air-cooled

Performance

• Power output: 165 hp (123 kW) at 2,800 rpm
• Specific power:
• Power-to-weight ratio:

The flat-6 engine of the Honda Valkyrie motorcycle A flat-6 is a 6 cylinder configuration of a flat engine or boxer engine. ... In engineering, specific power (sometimes also power per unit mass or power density) refers to the amount of power delivered by an energy source, divided by some measure of the sources size or mass. ... Power-to-weight ratio is a measure commonly used when comparing various vehicles (or engines), including automobiles, motorcycles and aircraft. ...

Reference

• Gunston, Bill. (1986) World Encyclopedia of Aero Engines. Patrick Stephens: Wellingborough. p.57
• Erickson, Jack. Horizontally-Opposed Piston Aero Engines
• US Department of Transportation Federal Aviation Administration Type Certificate Data Sheet E-238 Revision 12, December 8, 1994.