2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/85263Unlike a helicopter, an insect can, in theory, use both lift and drag to stay aloft. Here we show that a dragonfly uses mostly drag to hover by employing asymmetric up and down strokes. Computations of a family of strokes further show that using drag can be as efficient as using lift at the low Reynolds number regime appropriate for insects.8 pagesFluid DynamicsGeneral Physicstext