Powered Parachute Flying Handbook

Chapter 11 — Approaches and Landings

Stabilized Approach Concept

A stabilized approach is one in which the pilot establishes and maintains a constant angle glidepath towards a predetermined point on the landing runway. It is based on the pilot’s judgment of certain visual clues, and depends on the maintenance of a constant final approach.

A powered parachute descending on final approach at a constant rate will be traveling in a straight line toward a spot on the ground ahead. This spot will not be the spot on which the powered parachute will touch down, because some float will inevitably occur during the powered roundout and flare.

The point toward which the powered parachute is progressing is termed the “aiming point.” [Figure 11-8] It is the point on the ground at which, if the powered parachute maintains a constant glidepath, and was not rounded out or flared for landing, it would strike the ground. To a pilot moving straight ahead toward an object, it appears to be stationary. It does not “move.” This is how the aiming point can be distinguished—it does not move. However, objects in front of and beyond the aiming point do appear to move as the dis-tance is closed, and they appear to move in opposite directions. During instruction in landings, one of the most important skills a student pilot must acquire is how to use visual cues to accurately determine the true aiming point from any distance out on final approach. From this, the pilot will not only be able to determine if the glidepath will result in an undershoot or overshoot, but, taking into account float during roundout, the pilot will be able to predict the touchdown point to within a very few feet.

For a constant angle glidepath, the distance between the horizon and the aiming point will remain constant. If a final approach descent has been established but the distance between the perceived aiming point and the horizon appears to increase (aiming point moving down away from the horizon), then the true aiming point, and subsequent touchdown point, is farther down the runway. If the distance between the perceived aiming point and the horizon decreases (aiming point moving up toward the horizon), the true aiming point is closer than perceived.

When the powered parachute 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.

The objective of a stabilized approach is to select an appropriate touchdown point on the runway, and adjust the glidepath so the true aiming point and the desired touchdown point basically coincide. Immediately after rolling out on final approach, you should adjust the power so the powered parachute is descending directly toward the aiming point. With the approach set up in this manner, you will be free to devote full attention toward outside references. You should 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. In this way, you will be more apt to perceive a deviation from the desired glidepath, and whether or not the powered parachute is proceeding directly toward the aiming point.

If the aiming point on the runway is not where you want it, adjust the glidepath. This in turn will move the aiming point. For instance, if you perceive the aiming point is short of the desired touchdown point and will result in an undershoot, increase the engine power. The power change must be made smoothly. This will result in a shallower glidepath with the resultant aiming point moving towards the desired touchdown point. Conversely, if the aiming point is farther down the runway than the desired touchdown point and you suspect it will result in an overshoot, steepen the glidepath by decreasing power.

The closer the powered parachute gets to the runway, the larger (and possibly more frequent) the required corrections may become, resulting in an unstabilized approach.

Common errors in the performance of normal approaches and landings are:

• Inadequate wind drift correction on the base leg.
• Overshooting or undershooting the turn onto final approach resulting in too steep or too shallow a turn onto final approach.
• Unstabilized approach.
• Focusing too close to the powered parachute resulting in a too high roundout.
• Focusing too far from the powered parachute resulting in a too low roundout.
• Flaring the parachute too early before touchdown.
• Touching down prior to attaining proper landing attitude.
• Failure to release the flare after touchdown.

 ŠAvStop Online Magazine                                                                                                                                                       Contact Us              Return To Books

AvStop Aviation News and Resource Online Magazine

Grab this Headline Animator