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Instrument Flying Handbook
Airplane Basic Flight Maneuvers Using Analog Instrumentation
Straight-and-Level Flight

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Instrument Flying
Handbook

Preface

Table of Contents

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

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

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
Operations

Altimeter for Pitch Interpretation
Figure 5-7. Using the Altimeter for Pitch Interpretation, a High Altitude Means a Nose-High Pitch Attitude.

Pitch Correction Following Altitude Increase
Figure 5-8. Pitch Correction Following Altitude Increase-Lower
Nose to Correct Altitude Error

The rate of movement of the altimeter needle is as important
as its direction of movement in maintaining level flight
without the use of the attitude indicator. An excessive pitch
deviation from level flight results in a relatively rapid change
of altitude; a slight pitch deviation causes a slow change.
Thus, if the altimeter needle moves rapidly clockwise, assume
a considerable nose-high deviation from level flight attitude;
Conversely, if the needle moves slowly counterclockwise to
indicate a slightly nose-low attitude, assume that the pitch
collection necessary to regain the desired altitude is small.
As the altimeter is added to the attitude indicator in a cross-
check, a pilot will learn to recognize the rate of movement
of the altimeter needle for a given pitch change as shown on
the attitude indicator.

To practice precision control of pitch in an airplane without
an attitude indicator, make small pitch changes by visual
reference to the natural horizon, and note the rate of
movement of the altimeter. Note what amount of pitch change
gives the slowest steady rate of change on the altimeter. Then
practice small pitch corrections by accurately interpreting
and controlling the rate of needle movement.

 

An instructor pilot can demonstrate an excessive nose-down
deviation (indicated by rapid movement of the altimeter
needle) and then, as an example, show the result of improper
corrective technique. The normal impulse is to make a
large pitch correction in a hurry, but this inevitably leads
to over controlling. The needle slows down, then reverses
direction, and finally indicates an excessive nose-high
deviation. The result is tension on the controls, erratic control
response, and increasingly extreme control movements. The
correct technique, which is slower and smoother, will return
the airplane to the desired attitude more quickly, with positive
control and no confusion.

When a pitch error is detected, corrective action should be
taken promptly, but with light control pressures and two
distinct changes of attitude: (1) a change of attitude to stop
the needle movement and (2) a change of attitude to return
to the desired altitude.

When the altimeter indicates an altitude deviation, apply
just enough elevator pressure to decrease the rate of needle
movement If it slows down abruptly, ease off some of the
pressure until the needle continues to move, but ease off
slowly. Slow needle movement means the airplane attitude
is close to level flight. Add slightly more corrective pressure
to stop the direction of needle movement. At this point level
flight is achieved; a reversal of needle movement means
the aircraft has passed through it. Relax control pressures
carefully, continuing to cross-check since changing airspeed
will cause changes in the effectiveness of a given control
pressure. Next, adjust the pitch attitude with elevator pressure
for the rate of change of altimeter needle movement that is
correlated with normal pitch corrections, and return to the
desired altitude.

As a rule of thumb, for errors of less than 100 feet, use a half
bar width correction. [Figures 5-9 and 5-10] For error's in
excess of 100 feet, use an initial full bar width correction.
[Figures 5-11 and 5-12] Practice predetermined altitude
changes using the altimeter alone, then in combination with
the attitude indicator.

Vertical Speed Indicator (VSI)
The VSIs, like the altimeter, gives an indirect indication of
pitch attitude and is both a trend and a rate instrument. As
a trend instrument, it shows immediately the initial vertical
movement of the airplane, which disregarding turbulence
can he considered a reflection of pitch change. To maintain
level flight, use the VSI in conjunction with tile altimeter and
attitude indicator. Note any positive or negative trend of the
needle from zero and apply a very light corrective elevator

 
5-4