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1. Highly gregarious, and collectively noisy, they fly fast and direct, but often with rather laboured wing-beats and in V-formation.

2. Fast direct flight with quick clipped wing-beats; at rest bobs head when suspicious.

3. Flies with fast clipped wingbeats, always uttering its shrill, monosyllabic screech.

4. When mosquitoes fly, their wing would produce continuous wingbeat sounds.

5. At the end of each wingbeat, the controller schedules the desired angle of attack according to state feedback errors.

6. I heard a scream one night, and then heavy wingbeats.

7. No one knows, but the legend says that you will be able to hear a butterfly's wingbeat.