Water entry impact dynamics of diving birds.

Some seabirds (such as northern gannets and brown boobies) can dive from heights as high as 30 m reaching speeds of up to 24 m s as they impact the water surface. The physical geometry of plunge diving birds, particularly of the beak, allows them to limit high impact forces compared to non-diving birds. Numerically simulated data for one species (northern gannet) provides some insight into the impact forces experienced during diving, however, no reliable experimental data with real bird geometries exist for comparison purposes.

Water walking as a new mode of free surface skipping.

Deformable elastomeric spheres are evaluated experimentally as they skip multiple times over a lake surface. Some spheres are embedded with small inertial measurement units to measure the acceleration experienced during water surface impact. A model for multiple impact events shows good agreement between measured acceleration, number of skipping events and distanced traveled.