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Instrument Flying Handbook
Airplane Basic Flight Maneuvers Using an Electronic Flight Display
Straight-and-Level flight

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Instrument Flying


Table of Contents

Chapter 1. Human Factors
Chapter 2. Aerodynamic Factors
Chapter 3. Flight Instruments
Chapter 4. Section I
Airplane Attitude Instrument
Using Analog Instrumentation
Chapter 4. Section II
Airplane Attitude Instrument
Using an Electronic Flight

Chapter 5. Section I
Airplane Basic
Flight Maneuvers
Using Analog Instrumentation
Chapter 5. Section II
Airplane Basic
Flight Maneuvers
Using an Electronic Flight

Chapter 6. Helicopter
Attitude Instrument Flying

Chapter 7. Navigation Systems
Chapter 8. The National
Airspace System

Chapter 9. The Air Traffic
Control System

Chapter 10. IFR Flight
Chapter 11. Emergency

Sudden and exaggerated attitude changes may be necessary
in order to maintain straight-and-level flight as the landing
gear is extended and the flaps are lowered in some airplanes.
The nose Lends to pitch down with gear extension, and when
flaps are lowered, lift increases momentarily (at partial flap
settings) followed by a marked increase in drag as the flaps
near maximum extension.

Control technique varies according to the lift and drag
characteristics of each airplane. Accordingly, knowledge of
the power settings and trim changes associated with different
combinations of airspeed, gear, and flap configurations will
reduce instrument cross-check and interpretation problems.
[Figure 5-60]

For example, assume that in straight-and-level flight
instruments indicate 120 knots with power at 23" Hg
manifold pressure/2,300 revolutions per minute (rpm), gear
and flaps up. After reduction in airspeed, with gear and flaps
hilly extended, straight-and-level flight at the same altitude
requires 25" Hg manifold pressure/2,500 rpm. Maximum
gear extension speed is 115 knots; maximum flap extension
speed is 105 knots. Airspeed reduction to 95 knots, gear and
flaps down, can be made in the following manner:

1. Maintain rpm at 2,500, since a high power setting will
be used in full drag configuration.

2. Reduce manifold pressure to 10" Hg. As the airspeed
decreases, increase cross-check speed.

3. Make trim adjustments for an increased angle of attack
and decrease in torque.

4. Lower the gear at 115 knots. The nose may tend to
pitch down and the rate of deceleration increases.
Increase pitch attitude to maintain constant altitude,
and trim off some of the back-elevator pressures.
If full flaps are lowered at 105 knots, cross-check,
interpretation, and control must he very rapid. A
simpler technique is to stabilize attitude with gear
down before lowering the flaps.

5. Since 18" Hg manifold pressure will hold level
flight at 100 knots with the gear down, increase
power smoothly to that setting as the ASI shows
approximately 105 knots, and retrim. The attitude
indicator now shows approximately two-and-a-half
bar width nose-high in straight-and-level flight.

6. Actuate the flap control and simultaneously increase
power to the predetermined setting (25" Hg) for the
desired airspeed, and trim off the pressures necessary
to hold constant altitude and heading. The attitude
indicator now shows a bar width nose-low in straight-
and-level flight at 95 knots.

Cross-check Supporting Instruments,
Figure 5-60. Cross-check Supporting Instruments,