How does the direction of approach to impact speeds of ships mooring?

One of the main effects of the angle of the approaching speeds of ships, the influence of energy that are absorbed by the fender system. Consider some of the ships berth at the same pier at the same speed but with different slope angle, although their kinetic energies are equal, is different, the amount of energy absorbed by fenders. The amount of energy is absorbed by fender:
approaching velocities of ships

where W = energy absorbed by the fender
m = mass of ship
v = velocity of the vessel
k = radius of gyration of the ship
r = distance of center of gravity of the vessel to the point of the fender

So if the direction of the approaching speed of a ship is normal, the wings (ie, phi = 90), the quantity of energy absorbed less if it is a vessel whose tangential velocity is compared to the coast.

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