The Fiat A.24 was an Italian water-cooled aircraft engine from the 1920s, built in modest numbers. It produced 520 kW (700 hp).
|Number built||at least 100|
Design and development
During the second half of the 1920s Fiat introduced several water-cooled aircraft engines, including the A.20, A.22, A24, A.25 and A.30. They were all upright V-12s with 60° between the cylinder banks; capacities ranged between 18.7 L and 54.5 L (1,141-3,326 cu in) and power outputs between 320 kW and 745 kW (430-1,000 hp).
Producing 520 kW (700 hp) from 32.3 L (1,971 cu in), the A.24 was towards the centre of this range. When Fiat were advised by the government to simplify their water-cooled product line, they decided to focus on the A.20, A.22 and A.30 models so that the A.24 was not manufactured in large numbers.
- Initial version, ungeared.
- A.24 R.
- Geared output.
- Type: water-cooled 60° upright V-12
- Bore: 140 mm (5.51 in)
- Stroke: 175 mm (6.89 in)
- Displacement: 32.3 L (1,971 cu in)
- Length: 1.770 m (69.69 in)
- Width: 735 mm (28.9 in)
- Height: 1.065 m (41.93 in)
- Dry weight: Dry 550 kg (1,213 lb)
- Valvetrain: Two overhead camshafts, geared together, driving two inlet and two exhaust valves per cylinder. Housed under aluminium casings.
- Fuel system: Twin water heated Fiat carburetters mounted between cylinder banks, one serving each bank. Two spark plugs per cylinder, placed horizontally and opposite each other, supplied by two Marelli MF.12 magnetos.
- Oil system: One delivery pump and two scavenge pumps, in a single unit.
- Cooling system: water, with centrifugal pump.
- Reduction gear: 1.545:1 spur gear, lubricated via oil spout.
- Cylinders: Forged steel barrels, with closed, flat ends.
- Pistons: Aluminium alloy, two compression rings and two scraper rings above fully floating gudgeon pin.
- Crankshaft: Each six throw, seven bearings.
- Crankcase: Each an aluminium casting, split below crankshaft centre line. Bolted-on duralumin end caps.
- Power output: 520 kW (700 hp) at 2,000 rpm, continuous.
- Compression ratio: 5.7:1
- Fuel consumption: 0.302 kg/kW/h (0.496 lb/hp/h)
|Wikimedia Commons has media related to Fiat A.24.|
- Gunston, Bill (1989). World Encyclopaedia of Aero Engines (2 ed.). Wellingborough: Patrick Stephens Ltd. p. 57. ISBN 1-85260-163-9.
- Grey, C.G. (1972). Jane's All the World's Aircraft 1938. London: David & Charles. p. 69d. ISBN 0715 35734 4.
- Thompson, Jonathan (1963). Italian Civil and Military Aircraft 1930-1945. Fallbrook, California: Aero Publishers, Inc.