CHAPTER 13. Abnormal and Emergency Procedures

Terrain Types

Since an emergency landing on suitable terrain resembles a situation with which the pilot should be familiar through training, only the more unusual situation is discussed.

Confi ned Areas

The natural preference to set the aircraft down on the ground should not lead to the selection of an open spot between trees or obstacles where the ground cannot be reached. Once the intended touchdown point is reached, and the remaining open and unobstructed space is very limited, it may be better to force the aircraft down on the ground than to delay touchdown until it stalls (settles). An aircraft decelerates faster after it is on the ground than while airborne.

A river or creek can be an inviting alternative in otherwise rugged terrain. The pilot should ensure that the water or creek bed can be reached without snagging the wings. The same concept applies to road landings with one additional reason for caution: manmade obstacles on either side of a road may not be visible until the fi nal portion of the approach.

When planning the approach across a road, it should be remembered that most highways and even rural dirt roads are paralleled by power or telephone lines. Only a sharp lookout for the supporting structures or poles may provide timely warning.

If the only possible landing alternative is a small clearing and it is not possible to land the WSC aircraft, the BPS should be deployed, if equipped, as discussed earlier.

Trees

Although a tree landing is not an attractive prospect, the following general guidelines help to make the experience survivable.

For example, if the trees are taller than 15 feet and not dense enough to assure the wing could be set on top of them, use the BPS if so equipped. This provides two possible chances of hanging up in the trees and a slower descent rate if the WSC aircraft does not become lodged in the trees and continues a descent to the ground.

If the trees are estimated to be shorter than 15 feet or a BPS is not installed on the WSC aircraft, landing in the trees should be performed as follows:

  • Keep the groundspeed low by heading into the wind.
  • Make contact at minimum indicated airspeed, but not below stall speed, and “hang” the wing in the tree branches in a nose-high landing attitude. Involving the underside of the fuselage and both wings in the initial tree contact provides a more even and positive cushioning effect. Hold the control bar with both hands more than shoulder width apart and bend elbows to lessen the impact of the control bar against the chest. [Figure 13-5]

  • Avoid direct contact of the fuselage with heavy tree trunks.
  • Try to land in low, closely spaced trees with wide, dense crowns (branches) close to the ground, which are much better than tall trees with thin tops; the latter allow too much free fall height. (A free fall from 75 feet results in an impact speed of about 40 knots or about 4,000 fpm.)
  • Ideally, initial tree contact should be symmetrical; that is, both wings should meet equal resistance in the tree branches. This distribution of the load helps to maintain proper aircraft attitude. It may also preclude the loss of one wing, which invariably leads to a more rapid and less predictable descent to the ground.
  • If heavy tree trunk contact is unavoidable once the aircraft is on the ground, it is best to involve both wings simultaneously by directing the aircraft between two properly spaced trees. However, do not attempt this maneuver while still airborne.
 
 
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