Anzani 3-cylinder fan engines
| Industry | Aircraft engine manufacturing |
|---|---|
| Founded | 1905 |
| Founder | Alessandro Anzani |
| Products | Three-cylinder fan and radial aircraft engines |
Between 1905 and 1915, Alessandro Anzani engineered multiple three-cylinder configurations, including both fan and radial engine types. Among these was the engine that powered Louis Blériot's 1909 flight across the English Channel. An Anzani three-cylinder unit installed in a Blériot XI at The Shuttleworth Collection in England is recognized as the oldest operational aircraft engine worldwide.
Design and development
Beginning around 1905 in France, Alessandro Anzani crafted lightweight air-cooled engines for motorcycles, initially producing two-cylinder V-types before advancing to more powerful three-cylinder designs. These three-cylinder layouts—referred to as fan or W-3 engines—arranged cylinders radially over the upper semicircle to prevent spark plug fouling caused by lubricating oil, although this design required additional mass for piston counterbalancing.
Following increased French aviation enthusiasm after the Wright brothers' 1908 visit, Anzani developed a range of three-cylinder fan-type flight engines featuring iron-cast cylinders paired with aluminum crankcases. The outer cylinders were commonly angled at 60° relative to the center cylinder; one notable "cross channel" variant employed a 55° angle. These air-cooled inlet-over-exhaust (IOE) powerplants used crankcase-operated cams to actuate exhaust valves, while atmospheric inlet valves with spring assistance were positioned to enhance cooling. Cylinder bores ranged from 100 to 105 mm, with strokes between 120 and 150 mm, generating approximately 18 kW (24 hp) at speeds of 1,400–1,600 rpm.
Anzani’s three-cylinder fan engine famously powered Blériot's Type XI monoplane during the landmark Channel crossing in July 1909. Reports differ on its exact bore and stroke dimensions; early accounts suggest 100 × 150 mm (3.53 liters), whereas later technical drawings specify 103 × 120 mm (3.00 liters). Photographic evidence of the aircraft confirms the use of the 55° angled engine design.
Before this achievement, Anzani had introduced larger models: one with a 120 mm bore (4.4 liters) delivering 26 kW (35 hp), and another with a 135 mm bore (6.4 liters) producing 36 kW (45 hp). Production of these fan engines continued through at least 1913, incorporating improvements such as relocating exhaust valves to cylinder heads operated via pushrods and integrating a crankcase mixing chamber. By this time, cylinder spacing widened to 72°, which likely reduced the required counterbalance weight, and the inlet manifold was repositioned rearward to limit cooling airflow over the fuel-air mixture.
Radial (Y) engines
By December 1909, Anzani had introduced a balanced three-cylinder radial engine with cylinders spaced at 120°, known as the "Y" engine. This design produced 22 kW (30 hp) at 1,300 rpm from a displacement of 3.1 liters (186 cu in). Mounted inverted, it benefited from reduced spark plug fouling compared to other arrangements.
These radial engines offered smoother operation and lighter weight than fan-type counterparts but were constrained in power output due to having only three cylinders. They served as a foundation for Anzani’s subsequent two-row radial engines, beginning with six-cylinder units formed by pairing two Y-type engines on a shared crankshaft. A restored Bleriot XI, among the oldest flyable aircraft preserved in the U.S., continues to operate using this 120° "Y-type" radial engine.
Anzani 3-cylinder fan engines
- Power output: bore × stroke: displacement
- 10–12 hp (7.5–9 kW)
- 3.35 in × 3.35 in (85 mm × 85 mm): 88.5 cu in (1.45 L)
- 12–15 hp (9–11 kW)
- 3.35 in × 3.94 in (85 mm × 100 mm): 104 cu in (1.70 L)
- 25–30 hp (19–23 kW)
- 4.13 in × 5.12 in (105 mm × 130 mm): 206 cu in (3.38 L)
- 40–45 hp (30–34 kW)
- 5.32 in × 5.92 in (135 mm × 150 mm): 393 cu in (6.44 L)
- 45–50 hp (34–38 kW)
Anzani 3-cylinder inverted Y radial engines
- 40 hp
Applications
- ANBO-I (powered by the 3.38 L variant)
- Blériot XI
- Caproni-Pensuti triplane
- Deperdussin Type A
- Dufaux 4
- Fokker V.40
- Ford Flivver
- Medwecki HL-2
- Müller G.M.G. II
- Perry Beadle T.1
- Raab-Katzenstein RK.9 Grasmücke
- Sikorsky S-1
- Sikorsky S-2
- Stelmaszyk S.1 Bozena
- VIH Holland H.1
Surviving engines
At the Old Rhinebeck Aerodrome, a restored Blériot XI bearing French factory serial number 56 and U.S. registration N60094 operates short demonstration flights powered by its original Anzani three-cylinder "true radial" engine. Another Blériot XI, registered as G-AANG and slightly older, performs similar brief flights at the Shuttleworth Collection using its authentic fan-type Anzani engine, regarded as the oldest airworthy aircraft engine worldwide. Additionally, a 1910 Deperdussin monoplane is flown occasionally with a 'Y'-type Anzani engine.
An Anzani Y-type radial engine alongside the corresponding 1925 ANBO-I aircraft has been exhibited since the 1930s at the Lithuanian Aviation Museum located in Kaunas, Lithuania.
Engines on display
- The Shuttleworth Collection maintains Anzani three-cylinder engines for static exhibition.
- The Museo Nacional de Aeronáutica Argentina showcases a functional three-cylinder Anzani semiradial engine mounted on a Bleriot 11, as well as a Y-type three-cylinder engine within its Engines hall.
- The Brooklands Museum in Weybridge, U.K., displays an Anzani three-cylinder fan engine.