| Answer | Crossword Clue |
|---|---|
| ROTORS | Helicopter blades |
| ROTORS | Helicopter blades. |
| ROTOR | Helicopter system of blades. |
| ELM | Tree with seeds that whirl like helicopter blades |
| autorotations | Such rotation in the rotor blades of a helicopter that is descending without engine power |
| autorotation | Such rotation in the rotor blades of a helicopter that is descending without engine power |
| helicopter | a flying machine sustained by rotating blades revolving on a vertical axis above the machine / to travel by helicopter |
