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Airplane Flying Handbook
Transition to Multiengine Airplanes

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Airplane Flying Handbook


Table of Contents

Chapter 1,Introduction to Flight Training
Chapter 2,Ground Operations
Chapter 3,Basic Flight Maneuvers
Chapter 4, Slow Flight, Stalls, and Spins
Chapter 5, Takeoff and Departure Climbs
Chapter 6, Ground Reference Maneuvers
Chapter 7, Airport Traffic Patterns
Chapter 8, Approaches and Landings
Chapter 9, Performance Maneuvers
Chapter 10, Night Operations
Chapter 11,Transition to Complex Airplanes
Chapter 12, Transition to Multiengine Airplanes
Chapter 13,Transition to Tailwheel Airplanes
Chapter 14, Transition to Turbo-propeller Powered Airplanes
Chapter 15,Transition to Jet Powered Airplanes
Chapter 16,Emergency Procedures



When bank angle is plotted against climb performance
for a hypothetical twin, zero sideslip results in the best
(however marginal) climb performance or the least rate
of descent. Zero bank (all rudder to counteract yaw)
degrades climb performance as a result of moderate
sideslip. Using bank angle alone (no rudder) severely
degrades climb performance as a result of a large

The actual bank angle for zero sideslip varies among
airplanes from one and one-half to two and one-half
degrees. The position of the ball varies from one-third
to one-half of a ball width from instrument center.

For any multiengine airplane, zero sideslip can be confirmed
through the use of a yaw string. A yaw string is
a piece of string or yarn approximately 18 to 36 inches
in length, taped to the base of the windshield, or to the
nose near the windshield, along the airplane centerline.
In two-engine coordinated flight, the relative wind will
cause the string to align itself with the longitudinal axis
of the airplane, and it will position itself straight up the
center of the windshield. This is zero sideslip.
Experimentation with slips and skids will vividly display
the location of the relative wind. Adequate altitude and
flying speed must be maintained while accomplishing
these maneuvers.

With an engine set to zero thrust (or feathered) and the
airplane slowed to VYSE, a climb with maximum power
on the remaining engine will reveal the precise bank
angle and ball deflection required for zero sideslip and
best climb performance. Zero sideslip will again be
indicated by the yaw string when it aligns itself vertically
on the windshield. There will be very minor
changes from this attitude depending upon the
engine failed (with non counter-rotating propellers),
power available, airspeed and weight; but without
more sensitive testing equipment, these changes are
difficult to detect. The only significant difference
would be the pitch attitude required to maintain Vyse
under different density altitude, power available, and
weight conditions.

If a yaw string is attached to the airplane at the time
of a Vmc demonstration, it will be noted that Vmc
occurs under conditions of sideslip. Vmc was not
determined under conditions of zero sideslip during
aircraft certification and zero sideslip is not part of a
Vmc demonstration for pilot certification.

To review, there are two different sets of bank angles
used in one-engine-inoperative flight.

• To maintain directional control of a multiengine
airplane suffering an engine failure at low speeds
(such as climb), momentarily bank at least 5°,
and a maximum of 10° towards the operative
engine as the pitch attitude for Vyse is set. This
maneuver should be instinctive to the proficient
multiengine pilot and take only 1 to 2 seconds to
attain. It is held just long enough to assure directional
control as the pitch attitude for Vyse is

• To obtain the best climb performance, the airplane
must be flown at VYSE and zero sideslip,
with the failed engine feathered and maximum
available power from the operating engine. Zero
sideslip is approximately 2° of bank toward the
operating engine and a one-third to one-half ball
deflection, also toward the operating engine. The
precise bank angle and ball position will vary
somewhat with make and model and power
available. If above the airplane's single-engine
ceiling, this attitude and configuration will result
in the minimum rate of sink.

In OEI flight at low altitudes and airspeeds such as the
initial climb after takeoff, pilots must operate the airplane
so as to guard against the three major accident factors:
(1) loss of directional control, (2) loss of performance,
and (3) loss of flying speed. All have equal potential to
be lethal. Loss of flying speed will not be a factor,
however, when the airplane is operated with due regard
for directional control and performance.


There is nothing unusual about maneuvering during
slow flight in a multiengine airplane. Slow flight may
be conducted in straight-and-level flight, turns, in the
clean configuration, landing configuration, or at any
other combination of landing gear and flaps. Pilots
should closely monitor cylinder head and oil temperatures
during slow flight. Some high performance
multiengine airplanes tend to heat up fairly quickly
under some conditions of slow flight, particularly in
the landing configuration.

Simulated engine failures should not be conducted during
slow flight. The airplane will be well below VSSE
and very close to VMC. Stability, stall warning or stall
avoidance devices should not be disabled while
maneuvering during slow flight.