It follows then, that a slower landing speed reduces the potential for loss of control during the landing roll. It also means less strain on the tires, brakes and landing gear and reduces fatigue on the airframe structure. There are, of course, factors, which at times call for variance from the procedure of using full flaps on landing. With experience, a pilot learns to assess these various factors as a guide to flap selection. In some airplanes, in a crosswind condition, the use of full flap may be inadvisable.
Flaps present a greater surface for the wind to act upon when the airplane is rolling on the ground.
The wing on the side from which the wind is blowing will tend to rise. In addition, cross wind acting on full flaps increases the weather vaning tendencies, although in an airplane with very effective rudder control even at slow speeds, the problem is not so severe. However, in many airplanes, the selection of full flaps deflects the airflow from passing over the empennage, making the elevator and rudder surfaces ineffective. Positive control of the airplane on the ground is greatly hampered. Since maintaining control of the airplane throughout the landing roll is of utmost importance, it may be advisable to use less flaps in cross wind conditions.