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Airplane Flying Handbook
Transition to Multiengine Airplanes
ENGINE INOPERATIVE FLIGHT PRINCIPLES

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Airplane Flying Handbook

Preface

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

Glossary

Index

Single-engine go-arounds must be avoided. As a practical
matter in single-engine approaches, once the airplane
is on final approach with landing gear and flaps
extended, it is committed to land. If not on the intended
runway, then on another runway, a taxiway, or grassy
infield. The light-twin does not have the performance
to climb on one engine with landing gear and flaps
extended. Considerable altitude will be lost while
maintaining Vyse and retracting landing gear and
flaps. Losses of 500 feet or more are not unusual. If the
landing gear has been lowered with an alternate means
of extension, retraction may not be possible, virtually
negating any climb capability.

ENGINE INOPERATIVE FLIGHT PRINCIPLES

Best single-engine climb performance is obtained at
VYSE with maximum available power and minimum
drag. After the flaps and landing gear have been
retracted and the propeller of the failed engine feathered,
a key element in best climb performance is
minimizing sideslip.

With a single-engine airplane or a multiengine airplane
with both engines operative, sideslip is eliminated
when the ball of the turn and bank instrument is centered.
This is a condition of zero sideslip, and the
airplane is presenting its smallest possible profile to
the relative wind. As a result, drag is at its minimum.
Pilots know this as coordinated flight.

In a multiengine airplane with an inoperative engine,
the centered ball is no longer the indicator of zero
sideslip due to asymmetrical thrust. In fact, there is no
instrument at all that will directly tell the pilot the
flight conditions for zero sideslip. In the absence of a
yaw string, minimizing sideslip is a matter of placing
the airplane at a predetermined bank angle and ball
position. The AFM/POH performance charts for single-
engine flight were determined at zero sideslip. If
this performance is even to be approximated, the zero
sideslip technique must be utilized.

There are two different control inputs that can be used
to counteract the asymmetrical thrust of a failed
engine: (1) yaw from the rudder, and (2) the horizontal
component of lift that results from bank with the
ailerons. Used individually, neither is correct. Used
together in the proper combination, zero sideslip and
best climb performance are achieved.

Three different scenarios of airplane control inputs are
presented below. Neither of the first two is correct.
They are presented to illustrate the reasons for the zero
sideslip approach to best climb performance.

1. Engine inoperative flight with wings level and
ball centered requires large rudder input towards
the operative engine. [Figure 12-16] The result is
a moderate sideslip towards the inoperative
engine. Climb performance will be reduced by
the moderate sideslip. With wings level, Vmc will
be significantly higher than published as there is
no horizontal component of lift available to help
the rudder combat asymmetrical thrust.

Wings level engine-out flight
Figure 12-16. Wings level engine-out flight.

 

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