DESCENTS AND DESCENDING TURNS

Description

A fundamental maneuver whereby the airplane changes attitude from level to a descent attitude.

Objective

To develop the fundamental techniques required for decreasing altitude.

Elements

·         Clear the area

·         Choose forced landing area (always be aware of options)

·         Select outside references

·         Configure aircraft: reduce throttle then adjust pitch based on the type of descent:

o        Normal descent: reduce throttle to normal descent power (C172RG: 17” Hg, 2500 RPM), allow the nose to approx. pitch 5º below horizon then adjust as necessary to maintain either a standard rate (i.e. 500fpm) or constant airspeed (i.e. 90 KIAS).

o        Descent at minimum safe airspeed: reduce throttle to normal descent power (C172RG: 17” Hg, 2500 RPM), adjust pitch to achieve and maintain 1.3 V_SO or the short field approach speed (C172RG: 63 KIAS)

o        Glide: flaps and gear retracted, reduce throttle to idle and pitch for and maintain best glide speed (C172RG: Propeller 2700 RPM, 73 KIAS at MGW)

o        For turning climbs, bank at approx. 30º for new heading

·         Maintain ball centered

·         Trim to maintain descent rate or airspeed desired

·         Use outside references for descent

·         Upon reaching new altitude, anticipate altitude (approx. 100-150’), pitch for level flight, adjust power and trim as necessary

o        For turning descents, anticipate heading (approx. 50% of bank angle)

·         Look for traffic

Common Errors

·         Failure to adequately clear the area

·         Inadequate back-elevator control during glide entry resulting in too steep a glide

·         Failure to slow the airplane to approximate glide speed prior to lowering pitch attitude

·         Attempting to establish/maintain a normal glide solely by reference to flight instruments

·         Inability to sense changes in airspeed through sound and feel

·         Inability to stabilize the glide (chasing the airspeed indicator)

·         Attempting to “stretch” the glide by applying back-elevator pressure

·         Skidding or slipping during gliding turns due to inadequate appreciation of the difference in rudder action as opposed to turns with power

·         Failure to lower pitch attitude during gliding turn entry resulting in a decrease in airspeed

·         Excessive rudder pressure during recovery from gliding turns

·         Inadequate pitch control during recovery from straight glides

·         “Ground shyness”—resulting in cross-controlling during gliding turns near the ground

·         Failure to maintain constant bank angle during gliding turns

References

FAA-H-8083-3A Airplane Flying Handbook p. 3-15