3° approach angle  400 feet x 100 feet runway  1,600 feet from threshold  105 feet altitude Same runway, same approach angle  800 feet from threshold  52 feet altitude Same runway, same approach angle  400 feet from threshold  26 feet altitude Too high Proper descent angle Too low Figure 8-11.  Change in runway shape if approach becomes narrow or steep. Figure 8-10.  Runway shape during stabilized approach. out on final approach, adjust the pitch attitude and power so  that the airplane is descending directly toward the aiming  point at the appropriate airspeed, in the landing configuration,  and trimmed for “hands off” flight. With the approach set  up in this manner, the pilot is free to devote full attention  toward outside references. Do not stare at any one place,  but rather scan from one point to another, such as from the  aiming point to the horizon, to the trees and bushes along  the runway, to an area well short of the runway, and back to  the aiming point. This makes it easier to perceive a deviation  from the desired glide path and determine if the airplane is  proceeding directly toward the aiming point. When the airplane is established on final approach, the shape  of the runway image also presents clues as to what must be  done to maintain a stabilized approach to a safe landing. Obviously, runway is normally shaped in the form of an  elongated rectangle. When viewed from the air during the  approach, the phenomenon known as perspective causes the  runway to assume the shape of a trapezoid with the far end  looking narrower than the approach end and the edge lines  converging ahead. As an airplane continues down the glide path at a constant  angle (stabilized), the image the pilot sees is still trapezoidal  but of proportionately larger dimensions. In other words,  during a stabilized approach, the runway shape does not  change.  [Figure 8-10] If the approach becomes shallow, the runway appears to  shorten and become wider. Conversely, if the approach  is steepened, the runway appears to become longer and  narrower.  [Figure 8-11] If there is any indication that the aiming point on the runway  is not where desired, an adjustment must be made to the glide  path. This in turn moves the aiming point. For instance, if  the aiming point is short of the desired touchdown point  and results in an undershoot, an increase in pitch attitude  and engine power is warranted. A constant airspeed must  be maintained. The pitch and power change, therefore,  must be made smoothly and simultaneously. This results in  a shallowing of the glide path with the aiming point moving  towards the desired touchdown point. Conversely, if the  aiming point is farther down the runway than the desired  touchdown point resulting in an overshoot, the glide path is  steepened by a simultaneous decrease in pitch attitude and  The objective of a stabilized approach is to select an  appropriate touchdown point on the runway, and adjust  the glide path so that the true aiming point and the desired  touchdown point basically coincide. Immediately after rolling  8-10