CHAPTER 11. Approaches and Landings

Power-on Approach and Landing for Turbulant Air

Power-on approaches at an airspeed above the normal approach speed should be used for landing in turbulent air. This provides for more energy and positive control of the aircraft when strong horizontal wind gusts, wind sheer, or up and down drafts, are experienced. Like other power-on approaches (when the pilot can vary the amount of power), a coordinated combination of both speed and power adjustments is usually required. It is easiest to think of fl ying the aircraft onto the ground at an airspeed above the stall speed. The additional power provides the pilot the ability to reduce the descent rate to touch the wheels gently to the surface at a higher speed. Landing in turbulent air is where practice and experience in energy management are utilized. This precise coordination of power and speed for higher energy landings should fi rst be practiced in calm air and can be used as the next step in learning landings after the student becomes profi cient at low approaches.

To determine the additional approach speed to fl ying in turbulence, one procedure is to use the normal approach speed plus one-half of the wind gust factors. The wind gust factor is determined by how much the airspeed varies while fl ying. If the normal approach speed is 50 knots and the wind gusts are at 15 knots, an airspeed of 57 knots is appropriate. Another method is to ensure the aircraft is at least at VY speed plus the wind gust factor. In any case, the airspeed that the aircraft manufacturer recommends.

An adequate amount of power should be used to maintain the proper airspeed and descent path throughout the approach and the throttle retarded to idling position only after the main wheels contact the landing surface. Care must be exercised in not closing the throttle before the pilot is ready for touchdown. In this situation, the sudden or premature closing of the throttle may cause a sudden increase in the descent rate that could result in a hard landing.

Landings from power-on approaches in turbulence should be such that the touchdown is made with the aircraft in approximately level fl ight attitude. The pitch attitude at touchdown should be only enough to prevent the nosewheel from contacting the surface before the main wheels have touched the surface. Most WSC are designed so the front wheel is higher than the back wheels in this situation, but each WSC is different. This must be evaluated for each model. After touchdown, the pilot should reduce the throttle to idle and pull the control bar all the way to the chest to lower the nose and prevent the WSC aircraft from lifting off until it slows below the stall speed. The aircraft should be allowed to decelerate normally with the aerodynamic braking of the wing with the nose lowered, and assisted by the wheel brakes as required.

 
 
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