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| CHAPTER 11. Approaches and Landings
Roundout ( Flare) The roundout is a slow, smooth transition from a normal approach speed to a landing attitude, gradually rounding out the fl ightpath to one that is parallel with, and within a very few inches above, the runway. When the aircraft, in a normal descent, approaches within what appears to be 10 to 15 feet above the ground, the roundout or fl are should be started and be a continuous process slowing until the aircraft touches down on the ground. It should be noted that the terms “roundout” and “fl are” are defi ned and used interchangeably throughout the aviation industry for slowing the aircraft during fi nal approach and touching down. The term “roundout” is used in this handbook since it provides a better description for the WSC landing process and WSC students are more successful learning landings using the term roundout instead of fl are. As the aircraft reaches a height where the back wheels are one to two inches above the ground, the roundout is continued by gradually pushing the control bar forward as required to maintain one to two inches above the runway as the WSC aircraft slows. [Figure 11-9] This causes the aircraft’s nosewheel to gradually rise to the desired landing attitude. The AOA should be increased at a rate that allows the aircraft to continue fl ying just above the runway as forward speed decreases until the control bar is full forward and the back wheels settle onto the runway.
During the roundout, the airspeed is decreased to touchdown speed while the lift is controlled so the aircraft settles gently onto the landing surface. The roundout should be executed at a rate at which the proper landing attitude and the proper touchdown airspeed are attained simultaneously just as the wheels contact the landing surface. The rate at which the roundout is executed depends on the aircraft’s height above the ground, the rate of descent, and the airspeed. A roundout started excessively high must be executed more slowly than one from a lower height to allow the aircraft to descend to the ground while the proper landing attitude is being established. The rate of rounding out must also be proportionate to the rate of closure with the ground. When the aircraft appears to be descending very slowly, the increase in pitch attitude (slowing of the WSC) must be made at a correspondingly low rate. Visual cues are important in roundout at the proper altitude and maintaining the wheels a few inches above the runway until eventual touchdown. Roundout cues are dependent primarily on the angle at which the pilot’s central vision intersects the ground (or runway) ahead and slightly to the side. Proper depth perception is a factor in a successful roundout, but the visual cues used most are those related to changes in runway or terrain perspective and to changes in the size of familiar objects near the landing area such as fences, bushes, trees, hangars, and even sod or runway texture. The pilot should direct central vision at a shallow downward angle of 10° to 15° toward the runway as the roundout is initiated. [Figure 11-10]
Maintaining the same viewing angle causes the point of visual interception with the runway to move progressively rearward toward the pilot as the aircraft loses altitude. This is an important visual cue in assessing the rate of altitude loss. Conversely, forward movement of the visual interception point indicates an increase in altitude and would mean that the pitch angle was increased too rapidly resulting in an over roundout. The following are also used to judge when the wheels are just a few inches above the runway: location of the visual interception point in conjunction with assessment of fl ow velocity of nearby off-runway terrain, and the similarity in appearance of height above the runway ahead of the aircraft to the way it looked when the aircraft was taxied prior to takeoff. A common error during the roundout is rounding out too much and too fast. This error can easily be avoided by gradually increasing the AOA with a controlled descent until the wheels are one inch above the surface and never climbing during a roundout with a gradual and controlled roundout. |
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