2-stroke vs. 4-stroke Engines

When choosing the right engine for your new aircraft, one of the first questions you'll have to ask is should I use a 2-stroke or 4-stroke powerplant? There are several advantages to both engine configurations so we'll look at both and decide what's right for you. First, 2-strokes are light weight and able to run at very high rpm's. They are well suited for smaller high performance aircraft. 2-strokes also tend to be the common choice for beginners/training aircraft due to their ease of operation and minimal maintenance. Plus, they typically cost about half the price of a 4-stroke. Unfortunately, there is a big down side. 2-strokes will struggle under the heavy load of a big propellor or a slower heavy aircraft. They also burn through fuel very quickly, your flight times. 4-strokes on the other hand have very good fuel economy providing longer flight times or the ability to run a smaller fuel tank if necessary. They generate massive amounts of torque at low rpm's enabling you to run large propellors and pull larger, heavier aircraft with ease. You can run a 4-stroke with an open pipe or a mild silencer and the exhaust sound is quieter and more realistic. The only two downsides to the 4-stroke engine is its higher price tag and extra maintenance due to many more moving parts inside the engine. So both engines have their pros and cons, but personally I prefer a 4-stroke in most aircraft mainly because of there nice sound and good fuel economy.