The purpose of this section is to provide a brief review of the techniques of
attitude instrument flight, including stall and stall recovery manoeuvres.
Attitude instrument flying is an extension of the concept of attitude flying.
The establishment of a specific pitch and bank attitude, accompanied by a
designated power setting, will cause predictable aircraft performance.
Therefore, if pitch, bank and power are determined through reference to the
flight instruments and the desired performance is confirmed by these
instruments, the definition and technique of attitude instrument flight is
There are three basic ingredients to attitude instrument flying:
The human body is subject to sensations which are unreliable when
interpreting the aircraft's actual attitude; therefore, the pilot must learn to
disregard these sensations and control the aircraft through proper scan and
interpretation of the flight instruments.
Proper scan is vital to the instrument pilot. Of course, instrument
flying requires that certain instruments be used more often during particular
manoeuvres. This is called selective radial scan. During a constant
airspeed climb, for instance, the altimeter is less important than the airspeed
indicator. Under instrument meteorological conditions, the pilot uses the
attitude indicator to determine the aircraft's pitch and re-establish an
attitude that will correct the airspeed to the desired value.
The attitude indicator replaces the normal outside visual references;
therefore, it is the principal attitude control instrument for the radial scan.
When scanning, the pilot should regard the attitude indicator as the hub of a
wagon wheel", and the other instruments as spokes. (see Attitude
Indicator is Centre of Scan figure, below).
The second important ingredient in instrument flying is proper instrument
interpretation. The attitude indicator provides an artificial horizon
to replace the natural one; hence, proper interpretation is extremely
The last ingredient, aircraft control, results from scan and
interpretation. It is simply a matter of applying the proper control pressures
to attain the desired aircraft performance. These pressures are the same as in
visual flight except that smaller and smoother control inputs are required.
B. instrument flying concept
The concept of control and performance attitude instrument flying can be
applied. to any aspect of instrument flight. Under this concept, instruments are
divided into three broad categories: control, performance and
1. control instruments: Control instruments indicate attitude of the
aircraft and power (thrust/drag) being supplied to the aircraft. These
instruments are calibrated to permit adjustments in definite amounts. They
include the attitude indicator and engine control instruments (tachometer,
manifold pressure, RPM, EPR).
2. performance instruments: Performance instruments indicate the actual
performance of the aircraft, which can be determined from
the airspeed/mach, turn-and-bank, vertical speed indicators, altimeters,
heading indicator, turn co-ordinator, magnetic compass.
3. navigation instruments: Navigation instruments indicate the position
of the aircraft in relation to a particular navigational aid that has been
selected. These can include NDB, VOR, ILS, INS, GPS, Loran-C, and OMEGA.
C. Attitude and power control
Proper control of aircraft attitude is the result of knowing when and how
much to change attitude, and then smoothly changing it by a definite amount.
Aircraft attitude control is accomplished by proper use of the attitude
indicator. The attitude indicator provides an immediate, direct and
corresponding indication of any change in aircraft pitch and/or bank
Pitch changes are accomplished by changing the pitch attitude of the
reference line by set amounts in relation to the horizon bar. These changes are
made in bat widths or degrees, depending upon the type of attitude indicator. On
most attitude indicators a bat width represents approximately 2º of pitch
Bank changes are accomplished. by changing the bank attitude or bank pointers
by set amounts in relation to the bank scale. Normally, the bank scale is
graduated by 0º, 10º 20º, 30º, 60º and 90º, and this scale may be located at the
top or bottom of the attitude indicator. Generally, an angle of bank that
approximates the degrees to be turned is recommended; however, it should not
exceed 30º in instrument flight. The TAS and the desired rate of turn are
factors to be considered.
Proper power control results from the ability to smoothly establish or
maintain desired airspeeds in co-ordination with attitude changes. Power changes
are accomplished by throttle adjustment and with reference to the power
indicators. Little attention is required to ensure that the power indication
remains constant once it is established, because these indications are not
affected by such factors as turbulence, improper trim or inadvertent control
D. trim technique
The aircraft has been correctly trimmed when it maintains a desired attitude
with all control pressures neutralized. It is much easier to hold a given
attitude constant by relieving all control pressures. In addition, more
attention can then be devoted to the performance and navigation instruments and
other cockpit duties.
First, apply control pressure to establish a desired attitude and then adjust
the trim so that the aircraft will maintain that attitude when the flight
controls are neutralized. Trim the aircraft for co-ordinated flight by centring
the ball of the turn-and-slip indicator. This is done by using rudder trim in
the direction the ball is displaced from centre.
Changes in attitude, power or configuration may require a trim adjustment.
Independent use of trim to establish a change in aircraft attitude invariably
leads to erratic aircraft control and is not recommended. Smooth and precise
attitude changes are best attained by a combination of control pressures and
E. scan technique
Scanning, or cross checking as it is sometimes known, is the continuous and
logical observation of flight instruments. A methodical and meaningful
instrument scan is necessary to make appropriate changes in aircraft attitude
The control and performance concept of attitude instrument flying requires
that the pilot establish an aircraft attitude and power setting on the control
instruments which should result in the desired aircraft performance. The pilot
must be able to recognize the requirements for a change in attitude or power or
both. By cross checking the instruments properly (scan), the pilot can determine
the magnitude and direction of adjustment required to achieve the desired
Scan can be reduced to the proper division of attention and interpretation of
the flight instruments. Attention must be efficiently divided between the
control and performance instruments and in a sequence that will ensure
comprehensive coverage of the flight instruments. The pilot must quickly
interpret what he or she sees when looking at the instruments and must become
familiar with the factors to be considered in dividing his or her attention
A factor influencing scan technique is the characteristic manner in which
instruments respond to changes of attitude and power. The control instruments
provide direct and immediate indications of attitude and power changes. Changes
in the indications on the performance instruments will lag slightly behind
changes of attitude or power. This lag is due to inertia of the aircraft and the
operating principles and mechanisms of the performance instruments.
To develop the technique of always referring to the correct instrument at the
appropriate time, you must continually ask yourself these questions:
What information do I need?
Which instruments give me the needed information?
Is the information reliable?
As mentioned earlier, the attitude indicator is the only instrument that the
pilot should observe for any appreciable length of time. It is also the
instrument that the pilot should observe the greatest number of times. An
example of a scan demonstrates this; the pilot glances from the attitude
indicator, then a glance at the airspeed indicator, back to the attitude
indicator, and so forth (wagon wheel technique or radial scan). Of course
different phases of flight will require slightly different scan techniques. This
is called selective radial scan since the pilot will use particular instruments
to carry out a particular task.
A correct or incorrect scan can be recognized by analyzing certain symptoms
of aircraft control. Symptoms of insufficient reference to the control
instruments are readily recognizable. The pilot should have some definite
attitude and power indications in mind that should be maintained. If the
performance instruments fluctuate erratically through the desired indications,
then the pilot is probably not referring sufficiently to the control
instruments. This lack of precise aircraft control is called chasing the
Too much attention to the control instruments can be recognized by the
following symptoms - if the pilot has a smooth, positive and continuous control
over the indications of the control instruments but large deviations are
observed to occur slowly on the performance instruments, a closer scan of the
performance instruments is required.
The indications on some instruments are not as eye-catching as those on other
instruments. For example, a 4º heading change is not as obvious as a 300 to
400-feet per-minute change on the vertical-speed indicator. Through deliberate
effort and proper habit, the pilot must ensure that all the instruments are
included in the scan. If this is accomplished, deviations on the performance
instruments should be observed in their early stages.
A correct scan results in the continuous interpretation of the flight
instruments, which enables the pilot to maintain proper aircraft control at all
times. Remember, rapidly looking from one instrument to another without
interpretation is of no value. Instrument systems and the location of the flight
instruments vary. Pilot ability also varies. Therefore, each pilot should
develop their own rate and technique of checking the instruments which will
ensure a continuous and correct interpretation of the flight instruments.
F. adjusting attitude and power
The control and performance concept of attitude instrument flying requires
the adjustment of aircraft attitude and power to achieve the desired performance
in relation to the capabilities of your aircraft. A change of aircraft attitude
and/or power is required when any indication other than that desired is observed
on the performance instruments. However, it is equally important for the pilot
to know what to change and how much of a pitch, bank or power change is
The phrase "Attitude plus power equals performance" summarizes the philosophy
behind instrument flying. In other words, an aircraft's performance is the
product of attitude and power. Performance is expressed in terms of airspeed,
altitude, rate of climb or descent, or other criteria. If either attitude or
power is changed, a change in performance will result.
The pilot knows what to change by understanding which control instrument to
adjust to achieve the desired indications on the performance instruments. Bank
attitude control is used to maintain a heading or a desired angle of bank during
turns. Power control, in conjunction with a slight attitude change, may be used
for maintaining or changing the airspeed while at a constant altitude. Power may
also be used to establish a rate of climb or descent at a given airspeed or trim
How much to adjust the attitude or power or both is, initially, an estimate
based on familiarity with the aircraft and the amount the pilot desires to
change the indications on the performance instruments. After making a change of
attitude or power, the pilot should observe the performance instruments to see
if the desired change has occurred. If it has not, further adjustment is
To sum up, instrument flight is a continuous process of:
establishing an attitude and power setting on the control instruments;
These procedural steps can be applied to any instrument
manoeuvre and should
result in precise attitude instrument flying.
The following manoeuvres are described elsewhere for full and partial
instrument panels and will not be duplicated here:
Change of Airspeed; and,
Unusual Attitudes and Recoveries.
A. stalls and stall recovery
There are many different configurations from which to enter stall
however, for the purpose of this section, stalls will be discussed in reference
to the realm of operations most frequently encountered in instrument flight. The
entry procedures described are designed for training pilots to recover from
induced stalls for training purposes. These manoeuvres should be accomplished in
VMC at a safe altitude - normally with recovery planned for a minimum of 3000
ft. AGL. See the Aircraft Flight Manual for recommended procedures.
1. approach stalls
Straight-ahead: In the approach mode stall, the pilot establishes
the aircraft in the configuration suitable for the type of aircraft, i.e., flaps
and undercarriage positioned as specified in the aircraft flight manual as
appropriate for an approach to landing.
The pilot must maintain altitude by constantly increasing elevator back
pressure as the airspeed decreases toward the approach speed. When the approach
speed is attained, the pilot should decrease the pitch attitude of the miniature
aircraft in the attitude indicator to initiate a descent. When the aircraft is
established in a constant-rate, straight-ahead descent at approach speed the
pilot should increase the pitch attitude to approximately the second pitch
reference line above the horizon (normally 10º) to purposely induce a stall in
this configuration. The pilot must maintain the selected pitch attitude and
remain on the heading from which the manoeuvre was begun.
The pilot should start recovery when buffeting begins, by simultaneously
lowering the miniature aircraft to the horizon (or as required in the AFM) on
the attitude indicator and adding maximum allowable power. Maintaining the level
flight attitude causes the airspeed to increase. Once the aircraft reaches a
safe airspeed, the pilot should increase pitch to initiate a climb at this speed
until reaching the altitude from which the manoeuvre began.
Turning: The pilot executes a turning approach stall in much the
same manner as the straight-ahead approach stall (reducing power to the approach
setting; maintaining altitude until the airspeed has decreased until the
instrument indications have "settled down"). At this time the pilot increases
the pitch attitude smoothly to the section pitch reference line above the
horizon, and begins a 15º - 20º bank turn in either direction. The pilot
maintains the pitch and bank through the use of the attitude indicator until
The recovery procedure is the same as for the straight-ahead
approach stall except that the wings are to be levelled and the recovery heading
2. take-off and departure stalls
Straight-ahead: The pilot reduces power to flight idle, or
approximately 15 in. Hg manifold pressure, and maintains altitude, using the
attitude indicator, vertical speed indicator and altimeter as references. As the
airspeed decreases to lift-off speed, the pilot sets a wings-level,
straight-ahead climb and increases power at a pitch angle that causes a
power-on, straight-ahead stall.
The pilot accomplishes this by adjusting the pitch of the miniature aircraft
to the second pitch reference line above the horizon (or as required in the
aircraft type). The pilot must also maintain the initial heading until a stall
buffet occurs. As the airspeed decreases, the pilot must increase back elevator
pressure to hold the pitch attitude selected. Direction and control must be
maintained strictly by use of the rudder.
When the buffet occurs the pilot should pitch down to the horizon bar, add
maximum allowable power and allow the aircraft to accelerate. The recover
altitude should be maintained and the manoeuvre completed on the same heading as
used throughout the stall. After attaining climb airspeed, the pilot should
reduce power to the climb setting.
turning: The turning take-off and departure stall begins in the same
manner as the straight-ahead departure stall. The pilot reduces power and
maintains altitude. As the airspeed decreases to lift-off speed, the pilot
increases the pitch to the second pitch reference line, applies increased power
and a makes a 15º to 20º bank in either direction. The pilot maintains this
climbing turn attitude on the attitude indicator until a stall buffet occurs. To
recover, the pilot lowers the pitch attitude to the horizon bar, levels the
wings and maintains the recovery altitude and heading. As the airspeed
approaches climb, the pilot should reduce power to the climb setting.