I got the used Raptor V1.

I made my own training gear and tried to hover in my backyard.

However, I think I made a fairly hard landing (from 2 ft). Nothing seems broken though. Everything looks fine.

But the next time I tried to fly, the blade hardly turns even when the engine is screaming.

Also, I noticed that when I manually turn the main blade (engine off), the tail rotor is not turning sometimes. I used to remember the tail rotor always turns with the main blade correspondingly. But the belt is fine, nothing is the transmission seems off.

What's wrong? Thanks

Drop the engine and take a look at the clutch and the 1 way auto rotation bearing in the main gear. Also make sure the engine isn't just running backwards.

I'm guessing autorotation hub's one-way bearing has turned into a two-way bearing. Need some answers to confirm this.

When you say "engine is screaming" ... is the output side of the clutch (clutch housing) spinning? Is the pinion gear spinning the main gear? Does the tail rotor spin when the "engine is screaming"?

When you spun the main rotor by hand ... did you spin it in the correct direction?

The answer to these questions will tell you where the issue is but I'm guessing auto-hub. A backwards running engine or broken clutch wouldn't affect how the tail rotor functioned when the main rotor was turned by hand ... unless of course it was turned the wrong way and then we're back to square one.

Good Luck,
d.tipton