The Hirth F-30 is a horizontally opposed four-cylinder, two-stroke, carburetted aircraft engine, with optional fuel injection, designed for use on ultralight aircraft and homebuilts.
The F-30 is equipped with a dual capacitor discharge ignition system and is free-air-cooled, with optional fan cooling. The cylinder walls are electrochemically coated with Nikasil. Standard starting is electric start and recoil start is not an option. The reduction drive system available is the G-40 gearbox with optional reduction ratios of 2.03:1, 2.25:1, 2.64:1, 2.96:1 and 3.33:1. A centrifugal clutch is also available as optional equipment.
The engine runs on a 50:1 pre-mix of unleaded 93 octane auto fuel and oil.
F-30Four-cylinder horizontally opposed, two-stroke, aircraft engine with a dual 38 mm diaphragm carburetors. Produces 85 hp (63 kW) at 5,500 rpm if free-air-cooled or 80 hp (60 kW) at 5,500 rpm if fan cooled. It has a factory rated time between overhaul (TBO) of 1,200 hours. Currently in production.
F-30EFour-cylinder horizontally opposed, two-stroke, aircraft engine with fuel injection. Produces 90 hp (67 kW) at 5,500 rpm if free-air-cooled or 85 hp (63 kW) at 5,500 rpm if fan cooled. It has a factory rated TBO of 1,200 hours. Currently in production.
F-30SFour-cylinder horizontally opposed, two-stroke, aircraft engine with dual integral pumper carburetors. Produces 100 hp (75 kW) at 6200 rpm if free-air-cooled or 95 hp (71 kW) at 6,200 rpm if fan-cooled. It has a factory rated TBO of 1,000 hours. Currently in production.
F-30ESFour-cylinder horizontally opposed, two-stroke, aircraft engine with fuel injection. Produces 110 hp (82 kW) at 6,200 rpm if free-air-cooled or 105 hp (78 kW) at 6,200 rpm if fan-cooled. It has a factory rated TBO of 1,000 hours. Currently in production.
Data from Recreational Power Engineering
Type: Four-cylinder, two-stroke, horizontally opposed, aircraft engineBore: 72 mm (2.8 in)Stroke: 64 mm (2.5 in)Displacement: 1,042 cc (63.6 cu in)Length: 380 mm (15.0 in)Width: 660 mm (26.0 in)Height: 355 mm (14.0 in)Dry weight: 105 lb (47.6 kg), including starter and exhaust system, 129 lb (58.5 kg) with gearbox, exhaust system and electric start. Fan cooling adds 8.5 lb (3.9 kg)Fuel system: Fuel injectionFuel type: unleaded 93 octane auto fuelOil system: 50:1 fuel-oil premix or oil injectionCooling system: free-air or fanReduction gear: G-40 gearbox with reduction ratios of 2.03:1, 2.25:1, 2.64:1, 2.96:1 and 3.33:1 available. Optional centrifugal clutch.Power output: 110 hp (82 kW) at 6,200 rpm with free-air cooling, 105 hp (78 kW) at 6,200 rpm with fan coolingCompression ratio: 9.5:1