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gives the greatest altitude gain in the
shortest horizontal distance.
Best rate-of-climb airspeed (Vy)
gives the greatest altitude gain
in the shortest time.
Figure 3-14. Best angle of climb vs. best rate of climb.
Ch 03.qxd 7/13/04 11:08 AM Page 3-13
3-14
that at which it would stabilize. The pilot must be prepared
for this.
As a climb is started, the airspeed will gradually diminish.
This reduction in airspeed is gradual because of
the initial momentum of the airplane. The thrust
required to maintain straight-and-level flight at a given
airspeed is not sufficient to maintain the same airspeed
in a climb. Climbing flight requires more power than
flying level because of the increased drag caused by
gravity acting rearward. Therefore, power must be
advanced to a higher power setting to offset the
increased drag.
The propeller effects at climb power are a primary factor.
This is because airspeed is significantly slower
than at cruising speed, and the airplane’s angle of
attack is significantly greater. Under these conditions,
torque and asymmetrical loading of the propeller will
cause the airplane to roll and yaw to the left. To
counteract this, the right rudder must be used.
During the early practice of climbs and climbing turns,
this may make coordination of the controls seem awkward
(left climbing turn holding right rudder), but after
a little practice this correction for propeller effects will
become instinctive.
Trim is also a very important consideration during a
climb. After the climb has been established, the airplane
should be trimmed to relieve all pressures from
the flight controls. If changes are made in the pitch attitude,
power, or airspeed, the airplane should be
retrimmed in order to relieve control pressures.
When performing a climb, the power should be
advanced to the climb power recommended by the
manufacturer. If the airplane is equipped with a controllable-
pitch propeller, it will have not only an
engine tachometer, but also a manifold pressure gauge.
Normally, the flaps and landing gear (if retractable)
should be in the retracted position to reduce drag.
As the airplane gains altitude during a climb, the manifold
pressure gauge (if equipped) will indicate a loss
in manifold pressure (power). This is because the same
volume of air going into the engine’s induction system
gradually decreases in density as altitude increases.
When the volume of air in the manifold decreases, it
causes a loss of power. This will occur at the rate of
approximately 1-inch of manifold pressure for each
1,000-foot gain in altitude. During prolonged climbs,
the throttle must be continually advanced, if constant
power is to be maintained.
To enter the climb, simultaneously advance the throttle
and apply back-elevator pressure to raise the nose of the
airplane to the proper position in relation to the horizon.
As power is increased, the airplane’s nose will rise due
to increased download on the stabilizer. This is caused
by increased slipstream. As the pitch attitude increases
and the airspeed decreases, progressively more right
rudder must be applied to compensate for propeller
effects and to hold a constant heading.
After the climb is established, back-elevator pressure
must be maintained to keep the pitch attitude constant.
As the airspeed decreases, the elevators will try to
return to their neutral or streamlined position, and the
airplane’s nose will tend to lower. Nose-up elevator
trim should be used to compensate for this so that the
pitch attitude can be maintained without holding backelevator
pressure. Throughout the climb, since the
power is fixed at the climb power setting, the airspeed
is controlled by the use of elevator.
A cross-check of the airspeed indicator, attitude indicator,
and the position of the airplane’s nose in relation
to the horizon will determine if the pitch attitude is
correct. At the same time, a constant heading should
be held with the wings level if a straight climb is being
performed, or a constant angle of bank and rate of turn
if a climbing turn is being performed. [Figure 3-16]
To return to straight-and-level flight from a climb, it is
necessary to initiate the level-off at approximately 10
percent of the rate of climb. For example, if the airplane
is climbing at 500 feet per minute (f.p.m.), leveling off
should start 50 feet below the desired altitude. The nose
must be lowered gradually because a loss of altitude
will result if the pitch attitude is changed to the level
　
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