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sprockets, universals, drive gears, linkages and any
other accessible components should be checked for
condition and obvious defects. The airplane structure
to which the landing gear is attached should be
checked for distortion, cracks, and general condition.
All bolts and rivets should be intact and secure.
TAKEOFF AND CLIMB
Normally, the landing gear should be retracted after
lift-off when the airplane has reached an altitude
where, in the event of an engine failure or other
emergency requiring an aborted takeoff, the airplane
could no longer be landed on the runway. This procedure,
however, may not apply to all situations. Landing
gear retraction should be preplanned, taking into
account the length of the runway, climb gradient,
obstacle clearance requirements, the characteristics of
the terrain beyond the departure end of the runway, and
the climb characteristics of the particular airplane. For
example, in some situations it may be preferable, in the
event of an engine failure, to make an off airport forced
landing with the gear extended in order to take
advantage of the energy absorbing qualities of terrain
(see Chapter 16). In which case, a delay in retracting
the landing gear after takeoff from a short runway may
be warranted. In other situations, obstacles in the climb
path may warrant a timely gear retraction after takeoff.
Also, in some airplanes the initial climb pitch attitude
is such that any view of the runway remaining is
blocked, making an assessment of the feasibility of
touching down on the remaining runway difficult.
Premature landing gear retraction should be avoided.
The landing gear should not be retracted until a
positive rate of climb is indicated on the flight
instruments. If the airplane has not attained a positive
rate of climb, there is always the chance it may settle
back onto the runway with the gear retracted. This is
especially so in cases of premature lift-off. The pilot
should also remember that leaning forward to reach the
landing gear selector may result in inadvertent forward
pressure on the yoke, which will cause the airplane to
descend.
As the landing gear retracts, airspeed will increase and
the airplane’s pitch attitude may change. The gear may
take several seconds to retract. Gear retraction and
locking (and gear extension and locking) is
accompanied by sound and feel that are unique to the
specific make and model airplane. The pilot should
become familiar with the sounds and feel of normal
gear retraction so that any abnormal gear operation can
be readily discernable. Abnormal landing gear
retraction is most often a clear sign that the gear
extension cycle will also be abnormal.
APPROACH AND LANDING
The operating loads placed on the landing gear at
higher airspeeds may cause structural damage due to
the forces of the airstream. Limiting speeds, therefore,
are established for gear operation to protect the gear
components from becoming overstressed during flight.
These speeds are not found on the airspeed indicator.
They are published in the AFM/POH for the particular
airplane and are usually listed on placards in the
cockpit. [Figure 11-11] The maximum landing
extended speed (VLE ) is the maximum speed at which
the airplane can be flown with the landing gear
extended. The maximum landing gear operating speed
(VLO) is the maximum speed at which the landing gear
may be operated through its cycle.
The landing gear is extended by placing the gear
selector switch in the GEAR DOWN position. As the
landing gear extends, the airspeed will decrease and
the pitch attitude may increase. During the several
seconds it takes for the gear to extend, the pilot
should be attentive to any abnormal sounds or feel.
The pilot should confirm that the landing gear has
extended and locked by the normal sound and feel of
the system operation as well as by the gear position
indicators in the cockpit. Unless the landing gear has
been previously extended to aid in a descent to traffic
pattern altitude, the landing gear should be extended
by the time the airplane reaches a point on the downwind
leg that is opposite the point of intended
landing. The pilot should establish a standard
procedure consisting of a specific position on the
downwind leg at which to lower the landing gear.
Strict adherence to this procedure will aid the pilot in
avoiding unintentional gear up landings.
Figure 11-11. Placarded gear speeds in the cockpit.
Ch 11.qxd 5/7/04 8:50 AM Page 11-13
11-14
Operation of an airplane equipped with a retractable
　
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