The Rotax 447 is a 41.60NaN0, inline 2-cylinder, two-stroke aircraft engine, built by BRP-Rotax GmbH & Co. KG of Austria for use in ultralight aircraft.[1] [2]
The Rotax 447 is a development of the Rotax 377, increasing the power output from 260NaN0 to 29.50NaN0 by increasing the cylinder bore from 62 mm to 67.5 mm and the maximum rpm from 6500 to 6800. The modern 447 has a single breakerless, magneto capacitor-discharge ignition (CDI) system. Early (ca. 1988) models use a breaker point ignition system.
The Rotax 447 features piston-ported, air-cooled cylinder heads and cylinders, utilizing either a fan or free air for cooling. Lubrication is by use of pre-mixed fuel and oil. The engine can be equipped with either one or two piston-type float carburetors. The dual-carburetor version uses Bing model 84 carburetors. The single-carburetor version uses a Bing model 54 carburetor. An optional High Altitude Compensation kit is available. It is typically installed with an induction-pulse-driven diaphragm fuel pump to provide fuel pressure.
The engine's propeller drive is via a Rotax type B gearbox. The standard engine includes a muffler exhaust system with an extra after-muffler as optional. The standard starter is a recoil start type, with an electric starter optional. An integral alternating current generator producing 170 watts at 12 volts with external rectifier-regulator is optional. The engine includes an intake air filter and can be fitted with an intake silencer system.
The manufacturer acknowledges the design limitations of this engine, warning pilots: