The main rotor was starting to power up, and something about that seemed not to sit well with him.

If before, it could have slowed the main rotor, he said.

It looks as if the whole cabin's going round with the main rotor.

Similar to my assessment of the main rotors, these blades do the job just fine.

The main rotor and transmission system of the R-4 was retained.

I'll disengage the main rotor once we're on the ground.

The main rotor gearbox had been replaced during the recent maintenance.

The tail boom was also chopped off by the main rotor.

There was enough room behind the main rotor blades to accomplish that.

He could clearly make out the heavy drumbeat of the main rotor.

The French make their main rotors turn clockwise when viewed from above.

The main rotor shaft was able to tilt slightly for forward control.

Helicopters have several different configurations of one or more main rotors.

The main rotor blades struck the ground, and the helicopter turned over, coming to rest on its left side.

Must be something wrong with the main rotor blades.

We had sheared off three feet of the main rotor blade.

The main rotor slowed, causing it to hit the tail section.

The major differences are in the main rotor blades and dynamic components.

This will usually bring the main rotor blades to have slightly negative pitch.

The tail section hints at what other modifications might have been made to the far more important main rotor.

He came off the collector, then flattened the main rotor blades.

The machine rolled and the main rotor blades struck the ice.

As it prepared to land, the main rotor was struck by enemy gunfire.

The cause was a manufacturing defect in one of the main rotor blades.

I have found it to be a great help if the main rotor blades are covered with a glossy white material.