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water, the horizon becomes obscure and may result in a loss
of orientation. Even on clear nights, the stars may be refl ected
on the water surface which could appear as a continuous array
of lights making the horizon diffi cult to identify.
Lighted runways, buildings, or other objects may cause
illusions when seen from different altitudes. At an altitude
of 2,000 feet, a group of lights on an object may be seen
individually; while at 5,000 feet or higher, the same lights
could appear to be one solid light mass. These illusions
may become quite acute with altitude changes and, if not
overcome, could present problems in respect to approaches
to lighted runways.
Approaches and Landings
When approaching the airport to enter the traffi c pattern and
land, it is important that the runway lights and other airport
lighting be identifi ed as early as possible. If the airport layout
is unfamiliar to the pilot, sighting of the runway may be
diffi cult until very close-in due to the maze of lights observed
in the area. [Figure 12-12] The pilot should fl y toward the
rotating beacon until the lights outlining the runway are
distinguishable. To fl y a traffi c pattern of proper size and
direction, the runway threshold and runway-edge lights must
be positively identifi ed. Once the airport lights are seen, these
lights should be kept in sight throughout the approach.
Distance may be deceptive at night due to limited lighting
conditions. A lack of intervening references on the ground
and the inability of the pilot to compare the size and location
of different ground objects cause this. This also applies to
the estimation of altitude and speed. Consequently, more
dependence must be placed on fl ight instruments, particularly
the altimeter and the airspeed indicator.
When entering the traffi c pattern, allow for plenty of time to
complete the before landing checklist. If the heading indicator
contains a heading bug, setting it to the runway heading is
an excellent reference for the pattern legs.
Every effort should be made to maintain the recommended
airspeeds and execute the approach and landing in the
same manner as during the day. A low, shallow approach
is defi nitely inappropriate during a night operation. The
altimeter and VSI should be constantly cross-checked against
the aircraft’s position along the base leg and fi nal approach.
A visual approach slope indicator (VASI) is an indispensable
aid in alerting a pilot of too low of a glidepath. The typical
VASI is set to 3° for the recommended aircraft approach. This
19 to 1 glide ratio is too low for a WSC aircraft. A normal
glide ratio for WSC aircraft is 5 to 1, which is 11°, much
higher than the normal 3° to 4° used by aircraft. Therefore,
for WSC VASI fi nal approaches both white lights should
be visible. If a pilot sees red over white, or especially both
reds, the approach is too low and altitude should be gained,
or at least maintained to get above the normal VASI 3° to
4° approach at night. This steeper approach allows the WSC
aircraft to glide to the runway and land safely in the event of
engine failure. [Figure 12-13]
After turning onto the fi nal approach and aligning the aircraft
midway between the two rows of runway-edge lights, the
pilot should note and correct for any wind drift. Throughout
the final approach, pitch and power should be used to
maintain a stabilized approach. Usually, halfway through
the fi nal approach, the landing light should be turned on.
Earlier use of the landing light may be necessary because of
“Operation Lights On” or for local traffi c considerations. The
landing light is sometimes ineffective since the light beam
usually does not reach the ground from higher altitudes.
The light may even be refl ected back into the pilot’s eyes
by any existing haze, smoke, or fog. This disadvantage is
overshadowed by the safety considerations provided by using
the “Operation Lights On” procedure around other traffi c.
12-12
Both light bars are white—above the
normal aircraft glidepath, which is
recomended for WSC aircraft in
case of engine failure.
Use stabilized approach.
Above Aircraft Glidepath
Red over red—below the normal
aircraft glidepath, dangerously low
and must climb
Below Aircraft Glidepath
Far bar is red and near bar
is white—on the normal aircraft
glidepath, which is lower than the
WSC aircraft power-off glidepath
On Aircraft Glidepath
Figure 12-13. VASI.
The approach and landings should be made in the same
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Weight-Shift Control Aircraft Flying Handbook(141)
