Instrument Flight
Constant Airspeed Climbs and Descents
Throttle: As required to maintain airspeed
Pitch: As required to maintain level flight
Lead point for roll-out: 1/3 of the AOB
STANDARD RATE TURNS
Standard rate turns are performed at 3 degrees per second. Therefore a heading change of 30 degrees
should take 10 seconds to complete. To accomplish standard rate turns at different airspeeds, you will
have to vary the bank angle. A good rule of thumb for determining bank angle is to use approximately
20 percent of indicated airspeed. Because your maximum-allowed angle of bank for maneuvering the
aircraft in instrument flight is 30 degrees, you will not normally perform standard rate turns at cruise
altitude and airspeed. You will, however, use SRTs in the slow flight maneuver and the GCA pattern.
TIMED TURNS STANDARD RATE
Use the same procedures and AOB limitations as 1/2 SRT except: establishing and maintaining a
standard rate turn requires that you monitor the turn needle and adjust the bank angle as necessary to
achieve a 2 needle-width deflection.
Bank angle: Approximately 20 percent of IAS
Rate: 3 degrees per second
Throttle: As required to maintain airspeed
Pitch: As required to maintain altitude
Lead point for roll-out: 1/3 of the AOB
TIMED TURNS (PARTIAL PANEL)
Timed turns are standard or 1/2 standard rate turns performed for a specific duration of time to enable you
to turn to a specific heading. Because of the unreliability of the standby compass in turns, you will find it
necessary to perform timed turns from a known heading in the event of a heading system failure.
Use the standby compass to determine the total number of degrees of the desired heading change.
Compute the time required for the turn by dividing the heading change by the turn rate (1-1/2 or 3 per
second).
NOTE: For a half standard rate, a simpler method to determine timing is to count the heading change in
30-degree increments, each of which equals 20 seconds. In a 90-degree turn, there are 3, 30-degree
increments (30, 60, 90). Therefore, a 90-degree turn at 1/2 standard rate will take one minute.
(3 increments X 20 seconds each = 60 seconds)
As the clock’s second hand passes a cardinal point (3, 6, 9, or 12), smoothly roll into the turn, do not lead
time. Adjust the bank angle as necessary to establish a 1/2 standard rate turn (approximately 25 degrees
at 250 KIAS and 15,000 to 20,000 ft), and adjust pitch and power to maintain altitude and airspeed. If just
the heading is frozen or blanked, continue to use the attitude information on the ADI display, otherwise
use the standby AI for attitude reference. Because of its smaller size, the standby AI will appear to move
faster and less smoothly, and you should be careful not to overcontrol the aircraft when flying partial
panel. Correct only as necessary.
Roll out of the turn at the end of the computed time, readjusting pitch and power for level flight. Then
check the standby compass to confirm that you are on the desired heading.
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