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The ability of superhydrophobic surfaces to stay dry, self-clean and avoid biofouling is attractive for applications in biotechnology, medicine and heat transfer 1-10 . It requires that water droplets placed on superhydrophobic surfaces have large apparent contact angles (θ* > 150°) and low roll-off angles (θroll-off < 10°), realized with surfaces having low-surface-energy chemistry as well as micro-or nanoscale surface roughness that minimizes liquid-solid contact 11-17 . But rough surfaces where liquid contacts only a small

Engineering surfaces that promote rapid drop detachment1,2 is of importance to a wide range of applications including anti-icing3–5, dropwise condensation6, and self-cleaning7–9. Here we show how superhydrophobic surfaces patterned with lattices of submillimetre-scale posts decorated with nano-textures can generate a counter-intuitive bouncing regime: drops spread on impact and then leave the surface in a flattened, pancake shape without retracting. This allows for a four-fold reduction in contact time compared to conventional complete rebound1,10–13. We demonstrate that the pancake bouncing results from the rectification of capillary energy stored in the penetrated liquid into upward motion adequate to lift the drop. Moreover, the timescales for lateral drop spreading over the surface and for vertical motion must be comparable. In particular, by designing surfaces with tapered micro/nanotextures which behave as harmonic springs, the timescales become independent of the impact velocity, allowing the occurrence of pancake bouncing and rapid drop detachment over a wide range of impact velocities.