Friday, February 6, 2009

Initial Climb - Takeoffs And Departure Climbs

Upon lift-off, the airplane should be flying at approximately the pitch attitude that will allow it to accelerate
to VY. This is the speed at which the airplane will gain
the most altitude in the shortest period of time.

If the airplane has been properly trimmed, some back-
elevator pressure may be required to hold this attitude
until the proper climb speed is established. On the
other hand, relaxation of any back-elevator pressure
before this time may result in the airplane settling,
even to the extent that it contacts the runway.

The airplane will pick up speed rapidly after it
becomes airborne. Once a positive rate of climb is
established, the flaps and landing gear can be retracted
(if equipped).

It is recommended that takeoff power be maintained
until reaching an altitude of at least 500 feet above the
surrounding terrain or obstacles. The combination of
VY and takeoff power assures the maximum altitude
gained in a minimum amount of time. This gives the
pilot more altitude from which the airplane can be
safely maneuvered in case of an engine failure or other

Since the power on the initial climb is fixed at the takeoff
power setting, the airspeed must be controlled by making
slight pitch adjustments using the elevators. However,
the pilot should not fixate on the airspeed indicator when
making these pitch changes, but should, instead, continue
to scan outside to adjust the airplane's attitude in relation
to the horizon. In accordance with the principles of attitude flying, the pilot should first make the necessary
pitch change with reference to the natural horizon and
hold the new attitude momentarily, and then glance at the
airspeed indicator as a check to see if the new attitude is
correct. Due to inertia, the airplane will not accelerate or
decelerate immediately as the pitch is changed. It takes a
little time for the airspeed to change. If the pitch attitude
has been over or under corrected, the airspeed indicator
will show a speed that is more or less than that desired.
When this occurs, the cross-checking and appropriate
pitch-changing process must be repeated until the desired
climbing attitude is established.

When the correct pitch attitude has been attained, it
should be held constant while cross-checking it against
the horizon and other outside visual references. The

airspeed indicator should be used only as a check to
determine if the attitude is correct.

After the recommended climb airspeed has been established, and a safe maneuvering altitude has been
reached, the power should be adjusted to the recommended climb setting and the airplane trimmed to
relieve the control pressures. This will make it easier
to hold a constant attitude and airspeed.

During initial climb, it is important that the takeoff
path remain aligned with the runway to avoid drifting
into obstructions, or the path of another aircraft that
may be taking off from a parallel runway. Proper scanning techniques are essential to a safe takeoff and
climb, not only for maintaining attitude and direction,
but also for collision avoidance in the airport area.

When the student pilot nears the solo stage of flight
training, it should be explained that the airplane's
takeoff performance will be much different when the
instructor is out of the airplane. Due to decreased
load, the airplane will become airborne sooner and
will climb more rapidly. The pitch attitude that the
student has learned to associate with initial climb
may also differ due to decreased weight, and the
flight controls may seem more sensitive. If the situation is unexpected, it may result in increased tension
that may remain until after the landing. Frequently,
the existence of this tension and the uncertainty that
develops due to the perception of an "abnormal"
takeoff results in poor performance on the subsequent landing.

Common errors in the performance of normal takeoffs
and departure climbs are:

  • Failure to adequately clear the area prior to taxiing into position on the active runway.

  • Abrupt use of the throttle.

  • Failure to check engine instruments for signs of
    malfunction after applying takeoff power.

  • Failure to anticipate the airplane's left turning
    tendency on initial acceleration.

  • Overcorrecting for left turning tendency.

  • Relying solely on the airspeed indicator rather
    than developed feel for indications of speed and
    airplane controllability during acceleration and

  • Failure to attain proper lift-off attitude.

  • Inadequate compensation for torque/P-factor
    during initial climb resulting in a sideslip.

  • Over-control of elevators during initial climb-

  • Limiting scan to areas directly ahead of the airplane
    (pitch attitude and direction), resulting in
    allowing a wing (usually the left) to drop
    immediately after lift-off.
  • Failure to attain/maintain best rate-of-climb airspeed
  • Failure to employ the principles of attitude flying
    during climb-out, resulting in "chasing" the airspeed

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