The ... model airplane engine is a simple and elegant concept. The majority of these are not ... but “glow” or “nitro” engines. These names are due to the fuel and ... methods. Th
The two-stroke model airplane engine is a simple and elegant concept. The majority of these are not gasoline, but “glow” or “nitro” engines. These names are due to the fuel and combustion methods. The fuel itself contains methanol, nitro methane and oil. The combustion is due to a plug that glows instead of sparking (as in other common two-stroke engines).
While there are many variations on the design, the basic elements remain unchanged. There is a piston moving back and forth in a cylinder. The piston is connected by a hinged rod to a rotating crankshaft. There is a combustion event on every other stroke of the piston (at the beginning of the down-stroke). The combustion is caused by a platinum element in a heated glow plug, combined with a compressed fuel-air (and oil) mixture. There are also intake, exhaust and transfer ports, to move around fresh and used fuel. A carburetor is used to mix air with fuel in the required ratio for the power output needed.
The piston itself functions as a fuel-air-exhaust valve, eliminating the need for the extra parts found in the four stroke engine. The engine is also its own fuel pump, as the movement of the piston pressurizes the crankcase. The fuel carries its own oil, further simplifying the design. And last but not least, being able to remove the battery after the engine starts, due to the self-sustaining glow-plug, reduces weight considerably. This is very desirable in a model airplane engine.
These wonders of engineering are perfect powerhouses for our model airplanes. However, starting the engine and keeping it running is somewhat of an art form. Follow the included directions as closely as possible.
If you need more info about starting or troubleshooting these engines, visit the RC Airplane Advisor.