From red cells to snowboarding: a new concept for a train track.

Feng and Weinbaum [J. Fluid Mech. 422, 282 (2000)]] have shown that there is a remarkable dynamic similarity between a red cell gliding on the endothelial surface glycocalyx and a human snowboarding on fresh powder although they differ in mass by 10(15). The lift forces in each case are 4 orders of magnitude greater than classical lubrication theory. Herein we report the first measurements of the pore pressures generated on the time scale of snowboarding and show a feasibility of designing a train that can glide on a track whose permeability and elastic properties are similar to goose down.