Grip of steel: kinematics of a landing of birds depending on geometry and texture of a surface

Throughout thousands of years the mankind aspired in heavens, wishing to assimilate to birds. Many great minds, from Leonardo di ser Pyero da Vinchi to brothers Wright, designed the most various aircraft, one of which and remained on paper, and others became primogenitors of modern planes and helicopters. Now flight for the person is possible — bought a plane ticket and voila. The majority of us does not reflect at all on how this huge metal bird, capable to transfer us from one continent to another works...