Don't put one in a helicopter!

If you are building a helicopter, please don't try to use a 2-stroke. I'm a professional helicopter pilot with nearly 3,000 hours. When I was first starting out and hungry for flight time I worked for a company that was building kit-copters with 2-strokes. I put in almost 300 hours in those helicopters and I'm lucky to have come out alive. I had more engine seizures than I like to think about.

2-strokes rely on fuel flow for lubrication. That's fine for a fixed wing, since they reduce RPM when they reduce fuel flow. Helicopters must maintain a constant RPM and change fuel flow to adjust power. You're just asking for an engine seizure!

I'm sure most of you know more than I do about 2-strokes. I just know from experience they don't work in a helicopter, and don't want want anyone to get hurt.