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.
1 Directional stability: The distance from the aircraft c.g. to the most aft part of the airplane is usually smaller on canard aircraft. 2  This poses a problem for locating a vertical stabilizer and may result in very large vertical surfaces. ( 3 Note, however, that winglets may be used to advantage in this case.).