| He engaged the engine, causing two large screw propellers to whirl frantically and the wood and cloth contraption to lift off the ground. |
| As the colonel secured the engines and feathered the propellers, the aircraft momentarily became airborne because of the reduced drag. |
| In initial tests, some of the biomolecular motors spun their propellers for more than two hours, at eight revolutions per second. |
| We fly to Iasi, a remote university town in the north-east of Romania, on a tiny bone-shaker of a plane with propellers. |
| Flashing propellers carved the skies as a variety of innovative aircraft and daring pilots, many of them female, quested for fame and money. |
| As the ship tore through the defenseless nurseries, its propellers caught the fishery ropes and dragged the nurseries in its wake. |
