Unconventional lift-generating mechanisms in free-flying butterflies.

Journal article

Flying insects generate forces that are too large to be accounted for by conventional steady-state aerodynamics. To investigate these mechanisms of force generation, we trained red admiral butterflies, Vanessa atalanta, to fly freely to and from artificial flowers in a wind tunnel, and used high-resolution, smoke-wire flow visualizations to obtain qualitative, high-speed digital images of the air flow around their wings. The images show that free-flying butterflies use a variety of unconventional aerodynamic mechanisms to generate force: wake capture, two different types of leading-edge vortex, active and inactive upstrokes, in addition to the use of rotational mechanisms and the Weis-Fogh 'clap-and-fling' mechanism. Free-flying butterflies often used different aerodynamic mechanisms in successive strokes. There seems to be no one 'key' to insect flight, instead insects rely on a wide array of aerodynamic mechanisms to take off, manoeuvre, maintain steady flight, and for landing.

Authors: Srygley, R; Thomas, A

• Publication status: Published
• Journal: Nature
• Volume: 420
• Issue: 6916
• Pages: 660-664
• Publication date: 2002-12-01
• DOI: 10.1038/nature01223
• EISSN: 1476-4687
• ISSN: 0028-0836
• Language: English
• Keywords: Wing; Flight, Animal; Butterflies; Animals; Air Movements; Smoke; Flowers