曝光台 注意防骗
网曝天猫店富美金盛家居专营店坑蒙拐骗欺诈消费者
b. Precision Approach Path Indicator (PAPI).
The precision approach path indicator (PAPI) uses
light units similar to the VASI but are installed in a
single row of either two or four light units. These
systems have an effective visual range of about
5 miles during the day and up to 20 miles at night. The
row of light units is normally installed on the left side
of the runway and the glide path indications are as
depicted. (See FIG 2−1−5.)
FIG 2−1−5
Precision Approach Path Indicator (PAPI)
Slightly High
(3.2 Degrees)
White
Red
High
(More Than
3,5 Degrees)
On Glide Path
(3 Degrees)
Slightly Low
(2.8 Degrees)
Low
(Less Than
2.5 Degrees)
c. Tri-color Systems. Tri-color visual approach
slope indicators normally consist of a single light unit
projecting a three-color visual approach path into the
final approach area of the runway upon which the
indicator is installed. The below glide path indication
is red, the above glide path indication is amber, and
the on glide path indication is green. These types of
indicators have a useful range of approximately
one-half to one mile during the day and up to
five miles at night depending upon the visibility
conditions. (See FIG 2−1−6.)
FIG 2−1−6
Tri-Color Visual Approach Slope Indicator
Amber
Above Glide Path
On Glide Path
Below Glide Path
Amber
Green
Red
NOTE−
1. Since the tri-color VASI consists of a single light source which could possibly be confused with other light sources, pilots
should exercise care to properly locate and identify the light signal.
2. When the aircraft descends from green to red, the pilot may see a dark amber color during the transition from green to
red.
2/19/04 AIM
Airport Lighting Aids 2−1−5
d. Pulsating Systems. Pulsating visual approach
slope indicators normally consist of a single light unit
projecting a two-color visual approach path into the
final approach area of the runway upon which the
indicator is installed. The on glide path indication is
a steady white light. The slightly below glide path
indication is a steady red light. If the aircraft descends
further below the glide path, the red light starts to
pulsate. The above glide path indication is a pulsating
white light. The pulsating rate increases as the aircraft
gets further above or below the desired glide slope.
The useful range of the system is about four miles
during the day and up to ten miles at night.
(See FIG 2−1−7.)
FIG 2−1−7
Pulsating Visual Approach Slope Indicator
Above Glide Path
On Glide Path
Below Glide Path
Slightly Below Glide Path
Threshold
PULSATING WHITE
PULSATING RED
STEADY WHITE
STEADY RED
NOTE−
Since the PVASI consists of a single light source which could possibly be confused with other light sources, pilots should
exercise care to properly locate and identify the light signal.
e. Alignment of Elements Systems. Alignment
of elements systems are installed on some small
general aviation airports and are a low-cost system
consisting of painted plywood panels, normally black
and white or fluorescent orange. Some of these
systems are lighted for night use. The useful range of
these systems is approximately three-quarter miles.
To use the system the pilot positions the aircraft so the
elements are in alignment. The glide path indications
are shown in FIG 2−1−8.
FIG 2−1−8
Alignment of Elements
Above Glide Path On Glide Path Below Glide Path
AIM 2/19/04
2−1−6 Airport Lighting Aids
2−1−3. Runway End Identifier Lights (REIL)
REILs are installed at many airfields to provide rapid
and positive identification of the approach end of a
particular runway. The system consists of a pair of
synchronized flashing lights located laterally on each
side of the runway threshold. REILs may be either
omnidirectional or unidirectional facing the approach
area. They are effective for:
a. Identification of a runway surrounded by a
preponderance of other lighting.
b. Identification of a runway which lacks contrast
with surrounding terrain.
c. Identification of a runway during reduced
visibility.
2−1−4. Runway Edge Light Systems
a. Runway edge lights are used to outline the edges
of runways during periods of darkness or restricted
visibility conditions. These light systems are
classified according to the intensity or brightness they
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：
AIM航空信息手册2004上(58)
