Skin discoloration can be due to changes in melanin. Melanin is a skin pigment that gives color to the skin. Changes in melanin can also cause skin to be patchy. Treatment for skin discoloration includes using topical treatments.
Winglets increase an aircraft's operating efficiency by reducing what is called induced drag at the tips of the wings. An aircraft's wing is shaped to generate negative pressure on the upper surface and positive pressure on the lower surface as the aircraft moves forward.
Last update 9/15/2010 what's new. Frequently, the question arises as to what airfoil or airfoils were used in the wing design of a particular aircraft. Jane's All The World's Aircraft has been a good source of this information, but in many cases (particularly military aircraft) it doesn't list this information.