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When landing with a retracted nosewheel (and the
main gear extended and locked) the pilot should hold
the nose off the ground until almost full up-elevator
has been applied. [Figure 16-8] The pilot should then
release back pressure in such a manner that the nose
settles slowly to the surface. Applying and holding full
up-elevator will result in the nose abruptly dropping to
the surface as airspeed decays, possibly resulting in
burrowing and/or additional damage. Brake pressure
should not be applied during the landing roll unless
absolutely necessary to avoid a collision with obstacles.
If the landing must be made with only the nose gear
extended, the initial contact should be made on the aft
fuselage structure with a nose-high attitude. This
procedure will help prevent porpoising and/or wheelbarrowing.
The pilot should then allow the nosewheel
to gradually touch down, using nosewheel steering as
necessary for directional control.
SYSTEMS MALFUNCTIONS
ELECTRICAL SYSTEM
The loss of electrical power can deprive the pilot of
numerous critical systems, and therefore should not
be taken lightly even in day/VFR conditions. Most
in-flight failures of the electrical system are located
in the generator or alternator. Once the generator or
alternator system goes off line, the electrical source
in a typical light airplane is a battery. If a warning
light or ammeter indicates the probability of an alternator
or generator failure in an airplane with only one
generating system, however, the pilot may have very
little time available from the battery.
The rating of the airplane battery provides a clue to how
long it may last. With batteries, the higher the amperage
load, the less the usable total amperage. Thus a 25-amp
hour battery could produce 5 amps per hour for 5 hours,
but if the load were increased to 10 amps, it might last
only 2 hours. A 40-amp load might discharge the battery
fully in about 10 or 15 minutes. Much depends on the
battery condition at the time of the system failure. If the
battery has been in service for a few years, its power may
be reduced substantially because of internal resistance.
Or if the system failure was not detected immediately,
much of the stored energy may have already been used. It
is essential, therefore, that the pilot immediately shed
non-essential loads when the generating source fails.
[Figure 16-9] The pilot should then plan to land at the
nearest suitable airport.
What constitutes an “emergency” load following a
generating system failure cannot be predetermined,
because the actual circumstances will always be
somewhat different—for example, whether the flight
is VFR or IFR, conducted in day or at night, in clouds
or in the clear. Distance to nearest suitable airport can
also be a factor.
Figure 16-7. Landing with one main gear retracted.
Figure 16-8. Landing with nosewheel retracted.
Ch 16.qxd 5/7/04 10:30 AM Page 16-10
16-11
The pilot should remember that the electrically powered
(or electrically selected) landing gear and flaps will not
function properly on the power left in a partially
depleted battery. Landing gear and flap motors use up
power at rates much greater than most other types of
electrical equipment. The result of selecting these
motors on a partially depleted battery may well result in
an immediate total loss of electrical power.
If the pilot should experience a complete in-flight loss
of electrical power, the following steps should be
taken:
• Shed all but the most necessary electricallydriven
equipment.
• Understand that any loss of electrical power is
critical in a small airplane—notify ATC of the situation
immediately. Request radar vectors for a
landing at the nearest suitable airport.
• If landing gear or flaps are electrically controlled
or operated, plan the arrival well ahead of time.
Expect to make a no-flap landing, and anticipate
a manual landing gear extension.
PITOT-STATIC SYSTEM
The source of the pressure for operating the airspeed
indicator, the vertical speed indicator, and the altimeter
is the pitot-static system. The major components of the
pitot-static system are the impact pressure chamber
and lines, and the static pressure chamber and lines,
each of which are subject to total or partial blockage
by ice, dirt, and/or other foreign matter. Blockage of
the pitot-static system will adversely affect instrument
operation. [Figure 16-10 on next page]
Partial static system blockage is insidious in that it
may go unrecognized until a critical phase of flight.
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