Certified Flyers II
Duchess Multi-Engine Study Guide
3
over the operating engines wing causing more lift on that wing, thus roll towards the
inoperative engine.
To counteract this roll and yaw, rudder pressure must be applied to the side of the operational
engine to oppose these forces. Hence, “
Dead foot- Dead engine”
.
ZERO SIDESLIP CONDITION
The solution to maintaining aircraft heading
and reducing drag is to improve
performance using the
Zero Sideslip
Condition.
When the aircraft is banked into
the operating engine (2-5 degrees of bank),
the dihedral of the wing will create a
horizontal component of lift. The horizontal
component of lift minimizes rudder
deflection required to align the longitudinal
axis of the aircraft to the relative wind. In
addition to banking into the operating
engine, the appropriate amount of rudder
required is indicated by the inclinometer
ball being “split” towards the operating
engine’s side. The zero sideslip condition
must be flown for optimum aircraft
performance.
CLIMB PERFORMANCE AND
SERVICE CEILING
Climb performance is dependent on the
excess power needed to overcome drag.
When a twin-engine airplane loses an
engine, the airplane loses 50% of its
available power. This power loss results in a
loss of approximately 80% of the aircraft’s excess power and climb performance. Drag is a major
factor relative to the amount of excess power available. An increase in drag (such as the loss of
one engine) must be offset by additional power. This additional power is now taken from the
excess power, making it unavailable to aid the aircraft in the climb. When an engine is lost,
maximize thrust (full power) and minimize drag (flaps and gear up, feather prop, etc) in order to
achieve optimum single engine climb performance.
Drag Factors:
1.
Full Flaps- ~400 fpm approx.
2.
Windmilling Prop- ~400 fpm approx.
3.
Gear Extended- ~150 fpm approx.
Single-engine service ceiling-
the highest altitude at which the airplane can maintain a steady
rate of climb of 50 fpm with one engine operating at full power and one engine’s propeller
feathered