The 2301 Engine by Hirth Engines is an air-cooled, two-cylinder, two-stroke boxer petrol engine designed for use in light aviation devices, including Unmanned Aerial Vehicles (UAVs) and ultralight aircraft.
The 23 series features an air-cooled design, eliminating the need for a liquid cooling system, and operates as a two-stroke unit running on petrol. The two-cylinder boxer configuration provides a compact layout suitable for integration into lightweight airframes. The unit is part of Hirth Engines’ portfolio of two-stroke propulsion systems developed for applications requiring compact dimensions and low weight.
It delivers up to 36 kW (48.96 HP) at its best operating point and 32 kW (43.52 HP) at full throttle, with torque figures of 58 Nm and 46 Nm respectively. Maximum engine speed is approximately 6500 RPM. Specific fuel consumption is approximately 660 g/kWh at 6500 RPM and 550 g/kWh at the best operating point (70–80% load at half rated speed).
Measuring 446 mm in length, 473 mm in width, and 450 mm in height, it has a bore of 72 mm and stroke of 64 mm. Weight is approximately 30.2 kg without the exhaust system, with an additional 3.8 kg for the exhaust, and time between overhauls (TBO) is approximately 600 hours.
The system is equipped with dual ignition, an electrical starter, and a standard exhaust system, and can be configured with fuel injection and a belt reduction drive system. It is designed for use across UAVs, ultralight aircraft, and other light aviation devices.
