2-1-1. Approach Light Systems (ALS)
a. ALS provide the basic means to transition from
instrument flight to visual flight for landing.
Operational requirements dictate the sophistication
and configuration of the approach light system for a
particular runway.
b. ALS are a configuration of signal lights starting
at the landing threshold and extending into the
approach area a distance of 2400-3000 feet for
precision instrument runways and 1400-1500 feet for
nonprecision instrument runways. Some systems
include sequenced flashing lights which appear to the
pilot as a ball of light traveling towards the runway at
high speed (twice a second). (See
FIG 2-1-1.)
FIG 2-1-1
Precision & Nonprecision Configurations
2-1-2. Visual Glideslope Indicators
a. Visual Approach Slope Indicator (VASI)
1. The VASI is a system of lights so arranged to
provide visual descent guidance information during
the approach to a runway. These lights are visible
from 3-5 miles during the day and up to 20 miles or
more at night. The visual glide path of the VASI
provides safe obstruction clearance within plus or
minus 10 degrees of the extended runway centerline
and to 4 NM from the runway threshold. Descent,
using the VASI, should not be initiated until the
aircraft is visually aligned with the runway. Lateral
course guidance is provided by the runway or runway
lights.
2. VASI installations may consist of either 2, 4,
6, 12, or 16 light units arranged in bars referred to as
near, middle, and far bars. Most VASI installations
consist of 2 bars, near and far, and may consist of 2,
4, or 12 light units. Some VASIs consist of three bars,
near, middle, and far, which provide an additional
visual glide path to accommodate high cockpit
aircraft. This installation may consist of either 6 or
16 light units. VASI installations consisting of 2, 4, or
6 light units are located on one side of the runway,
usually the left. Where the installation consists of
12 or 16 light units, the units are located on both sides
of the runway.
3. Two-bar VASI installations provide one
visual glide path which is normally set at 3 degrees.
Three-bar VASI installations provide two visual glide
paths. The lower glide path is provided by the near
and middle bars and is normally set at 3 degrees while
the upper glide path, provided by the middle and far
bars, is normally 1/4 degree higher. This higher glide
path is intended for use only by high cockpit aircraft
to provide a sufficient threshold crossing height.
Although normal glide path angles are three degrees,
angles at some locations may be as high as 4.5 degrees
to give proper obstacle clearance. Pilots of high
performance aircraft are cautioned that use of VASI
angles in excess of 3.5 degrees may cause an increase
in runway length required for landing and rollout.
4. The basic principle of the VASI is that of color
differentiation between red and white. Each light unit
projects a beam of light having a white segment in the
upper part of the beam and red segment in the lower
part of the beam. The light units are arranged so that
the pilot using the VASIs during an approach will see
the combination of lights shown below.
5. For 2-bar VASI (4 light units) see
FIG 2-1-2.
6. For 3-bar VASI (6 light units) see
FIG 2-1-3.
7. For other VASI configurations see
FIG 2-1-4.
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)
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
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.
FIG 2-1-7
Pulsating Visual Approach Slope Indicator
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.
FIG 2-1-8
Alignment of Elements
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.)
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.
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
are capable of producing: they are the High Intensity
Runway Lights (HIRL), Medium Intensity Runway
Lights (MIRL), and the Low Intensity Runway
Lights (LIRL). The HIRL and MIRL systems have
variable intensity controls, whereas the LIRLs
normally have one intensity setting.
b. The runway edge lights are white, except on
instrument runways yellow replaces white on the last
2,000 feet or half the runway length, whichever is
less, to form a caution zone for landings.
c. The lights marking the ends of the runway emit
red light toward the runway to indicate the end of
runway to a departing aircraft and emit green outward
from the runway end to indicate the threshold to
landing aircraft.
2-1-5. In-runway Lighting
a. Runway Centerline Lighting System
(RCLS). Runway centerline lights are installed on
some precision approach runways to facilitate
landing under adverse visibility conditions. They are
located along the runway centerline and are spaced at
50-foot intervals. When viewed from the landing
threshold, the runway centerline lights are white until
the last 3,000 feet of the runway. The white lights
begin to alternate with red for the next 2,000 feet, and
for the last 1,000 feet of the runway, all centerline
lights are red.
b. Touchdown Zone Lights (TDZL). Touchdown zone lights are installed on some precision
approach runways to indicate the touchdown zone
when landing under adverse visibility conditions.
They consist of two rows of transverse light bars
disposed symmetrically about the runway centerline.
The system consists of steady-burning white lights
which start 100 feet beyond the landing threshold and
extend to 3,000 feet beyond the landing threshold or
to the midpoint of the runway, whichever is less.
c. Taxiway Centerline Lead-Off Lights. Taxiway centerline lead-off lights provide visual
guidance to persons exiting the runway. They are
color-coded to warn pilots and vehicle drivers that
they are within the runway environment or
instrument landing system/microwave landing system (ILS/MLS) critical area, whichever is more
restrictive. Alternate green and yellow lights are
installed, beginning with green, from the runway
centerline to one centerline light position beyond the
runway holding position or ILS/MLS critical area
holding position.
d. Taxiway Centerline Lead-On Lights. Taxiway centerline lead-on lights provide visual
guidance to persons entering the runway. These
"lead-on" lights are also color-coded with the same
color pattern as lead-off lights to warn pilots and
vehicle drivers that they are within the runway
environment or instrument landing system/microwave landing system (ILS/MLS) critical area,
whichever is more conservative. The fixtures used for
lead-on lights are bidirectional, i.e., one side emits
light for the lead-on function while the other side
emits light for the lead-off function. Any fixture that
emits yellow light for the lead-off function shall also
emit yellow light for the lead-on function.
(See FIG 2-1-9.)
e. Land and Hold Short Lights. Land and hold
short lights are used to indicate the hold short point on
certain runways which are approved for Land and
Hold Short Operations (LAHSO). Land and hold
short lights consist of a row of pulsing white lights
installed across the runway at the hold short point.
Where installed, the lights will be on anytime
LAHSO is in effect. These lights will be off when
LAHSO is not in effect.
REFERENCE-
AIM, Pilot Responsibilities When Conducting Land and Hold Short
Operations (LAHSO), Paragraph 4-3-11.
2-1-6. Runway Status Light (RWSL)
System
a. Introduction.
RWSL is a fully automated system that provides
runway status to pilots and surface vehicle operators
to indicate clearly when it is unsafe to enter, cross, or
takeoff from a runway. The RWSL system processes
information from surveillance systems and illuminates Runway Entrance Lights (REL) and Takeoff
Hold Lights (THL) in accordance with the motion of
the detected traffic. REL and THL are in-pavement
fixtures that are directly visible to pilots and surface
vehicle operators. RWSL is an independent safety
enhancement that does not substitute for an ATC
clearance. Clearance to enter, cross, or takeoff from
a runway must be issued by ATC. ATC personnel do
not directly use, and may not be able to view, light
fixture output in their operations even though ATC
has limited control over the system.
b. Runway Entrance Lights (REL): The REL
system is composed of flush mounted, in-pavement,
unidirectional fixtures that are parallel to and focused
along the taxiway centerline toward the hold line.
Fixtures are located at the runway centerline, the
runway edge, and the runway hold line; additional
fixtures are evenly spaced between those at the hold
line and the runway edge (see FIG 2-1-9.) When
activated, the red lights indicate that there is high
speed traffic on the runway or there is an aircraft on
final approach within the activation area.
FIG 2-1-9
Runway Status Light System
1. Operating Characteristics - Departing Aircraft:
When a departing aircraft reaches 30 knots, all
taxiway intersections with REL arrays along the
runway ahead of the aircraft illuminate (see FIG 2-1-9.) As the aircraft approaches an REL
equipped taxiway intersection, the lights at that
intersection extinguish approximately 2 to 3 seconds
before the aircraft reaches it. This allows controllers
to apply “anticipated separation" to permit ATC to
move traffic more expeditiously without compromising safety. After the aircraft is declared “airborne"
by the system, all lights will extinguish.
2. Operating Characteristics - Arriving Aircraft:
When an aircraft on final approach is approximately
1 mile from the runway threshold all light arrays
along the runway illuminate. The distance is
adjustable and can be configured for specific
operations at particular airports. Lights extinguish at
each equipped taxiway intersection approximately 2
to 3 seconds before the aircraft reaches it to apply
anticipated separation until the aircraft has slowed to
approximately 80 knots (site adjustable parameter.)
Below 80 knots, all arrays that are not within 30
seconds of the aircraft's forward path are extinguished. Once the arriving aircraft slows to
approximately 34 knots (site adjustable parameter),
it is declared to be in a taxi state, and all lights
extinguish.
3. What a pilot would observe: A pilot at or
approaching the hold line to a runway will observe
REL illumination and extinguishing in reaction to an
aircraft or vehicle operating on the runway, or an
arriving aircraft operating less than 1 mile from the
runway threshold.
4. Whenever a pilot observes the red lights of
the REL, that pilot will stop at the hold line, or remain
stopped. The pilot will then contact ATC for
resolution if the clearance is in conflict with the
lights. Should pilots note illuminated lights under
circumstances when remaining clear of the runway is
impractical for safety reasons (i.e., aircraft is already
on the runway), the crew should proceed according to
their best judgment while understanding the
illuminated lights indicate the runway is unsafe to
enter or cross. Contact ATC at the earliest possible
opportunity.
c. Takeoff Hold Lights (THL) : The THL system
is composed of flush mounted, in-pavement,
unidirectional fixtures in a double longitudinal row
aligned either side of the runway centerline lighting.
Fixtures are focused toward the arrival end of the
runway at the “position and hold" point, and they
extend for 1,500 feet in front of the holding aircraft
(see FIG 2-1-9.) Illuminated red lights provide a
signal, to an aircraft in position for takeoff or rolling,
that it is unsafe to takeoff because the runway is
occupied or about to be occupied by another aircraft
or ground vehicle. Two aircraft, or a surface vehicle
and an aircraft, are required for the lights to
illuminate. The departing aircraft must be in position
for takeoff or beginning takeoff roll. Another aircraft
or a surface vehicle must be on or about to cross the
runway.
1. Operating Characteristics - Departing Aircraft:
THLs will illuminate for an aircraft in position for
departure or departing when there is another aircraft
or vehicle on the runway or about to enter the runway
(see FIG 2-1-9.) Once that aircraft or vehicle exits
the runway, the THLs extinguish. A pilot may notice
lights extinguish prior to the downfield aircraft or
vehicle being completely clear of the runway but still
moving. Like RELs, THLs have an “anticipated
separation" feature.
NOTE-
When the THLs extinguish, this is not clearance to begin a
takeoff roll. All takeoff clearances will be issued by ATC.
2. What a pilot would observe: A pilot in
position to depart from a runway, or has begun takeoff
roll, will observe THL illuminate in reaction to an
aircraft or vehicle on the runway or about to enter or
cross it. Lights will extinguish when the runway is
clear. A pilot may observe several cycles of
illumination and extinguishing depending on the
amount of crossing traffic.
3. Whenever a pilot observes the red light of the
THLs, the pilot will stop or remain stopped. The pilot
will contact ATC for resolution if any clearance is in
conflict with the lights. Should pilots note
illuminated lights while in takeoff roll and under
circumstances when stopping is impractical for safety
reasons, the crew should proceed according to their
best judgment while understanding the illuminated
lights indicate that continuing the takeoff is unsafe.
Contact ATC at the earliest possible opportunity.
d. Pilot Actions
1. When operating at airports with RWSL,
pilots will operate with the transponder “On" when
departing the gate or parking area until shutdown
upon arrival at the gate or parking area. This ensures
interaction with the FAA surveillance systems which
provide information to RWSL system.
2. Pilots will always inform ATCT when you've
stopped due to RWSL indications that are in conflict
with ATC instructions, and request clarification of
the taxi or takeoff clearance.
3. Never cross over illuminated red lights.
Under normal circumstances, RWSL will confirm the
pilot's taxi or takeoff clearance. If RWSL indicates
that it is unsafe to takeoff from or taxi across a
runway, immediately notify ATC of the conflict and
confirm your clearance.
4. Do not proceed when lights have extinguished without an ATC clearance. RWSL verifies an
ATC clearance, it does not substitute for an ATC
clearance.
e. ATC Control of RWSL system:
1. Controllers can set lights to one of five (5)
brightness levels to assure maximum conspicuity
under all visibility and lighting conditions. REL and
THL subsystems may be independently set.
2. The system can be shutdown should RWSL
operations impact the efficient movement of air
traffic or contribute, in the opinion of the ATC
Supervisor, to unsafe operations. REL and THL
subsystems may be shutdown separately. Whenever
the system or a component is shutdown, a NOTAM
will be issued, and the Automatic Terminal
Information System (ATIS) will be updated.
2-1-7. Control of Lighting Systems
a. Operation of approach light systems and
runway lighting is controlled by the control tower
(ATCT). At some locations the FSS may control the
lights where there is no control tower in operation.
b. Pilots may request that lights be turned on or off.
Runway edge lights, in-pavement lights and
approach lights also have intensity controls which
may be varied to meet the pilots request. Sequenced
flashing lights (SFL) may be turned on and off. Some
sequenced flashing light systems also have intensity
control.
2-1-8. Pilot Control of Airport Lighting
Radio control of lighting is available at selected
airports to provide airborne control of lights by
keying the aircraft's microphone. Control of lighting
systems is often available at locations without
specified hours for lighting and where there is no
control tower or FSS or when the tower or FSS is
closed (locations with a part-time tower or FSS) or
specified hours. All lighting systems which are radio
controlled at an airport, whether on a single runway
or multiple runways, operate on the same radio
frequency. (See
TBL 2-1-1 and
TBL 2-1-2.)
FIG 2-1-9
Taxiway Lead-On Light Configuration
TBL 2-1-1
Runways With Approach Lights
Lighting System
|
No. of Int.
Steps
|
Status During
Nonuse Period
|
Intensity Step Selected Per No.
of Mike Clicks
|
|
|
|
3 Clicks
|
5 Clicks
|
7 Clicks
|
Approach Lights (Med. Int.)
|
2
|
Off
|
Low
|
Low
|
High
|
Approach Lights (Med. Int.)
|
3
|
Off
|
Low
|
Med
|
High
|
MIRL
|
3
|
Off or Low
|
◆
|
◆
|
◆
|
HIRL
|
5
|
Off or Low
|
◆
|
◆
|
◆
|
VASI
|
2
|
Off
|
✬
|
✬
|
✬
|
NOTES: ◆ Predetermined intensity step.
✬ Low intensity for night use. High intensity for day use as determined by photocell control.
|
TBL 2-1-2
Runways Without Approach Lights
Lighting System
|
No. of Int.
Steps
|
Status During
Nonuse Period
|
Intensity Step Selected Per No.
of Mike Clicks
|
|
|
|
3 Clicks
|
5 Clicks
|
7 Clicks
|
MIRL
|
3
|
Off or Low
|
Low
|
Med.
|
High
|
HIRL
|
5
|
Off or Low
|
Step 1 or 2
|
Step 3
|
Step 5
|
LIRL
|
1
|
Off
|
On
|
On
|
On
|
VASI✬
|
2
|
Off
|
◆
|
◆
|
◆
|
REIL✬
|
1
|
Off
|
Off
|
On/Off
|
On
|
REIL✬
|
3
|
Off
|
Low
|
Med.
|
High
|
NOTES: ◆ #32; Low intensity for night use. High intensity for day use as determined by photocell control.
✬ #32; The control of VASI and/or REIL may be independent of other lighting systems.
|
a. With FAA approved systems, various combinations of medium intensity approach lights, runway
lights, taxiway lights, VASI and/or REIL may be
activated by radio control. On runways with both
approach lighting and runway lighting (runway edge
lights, taxiway lights, etc.) systems, the approach
lighting system takes precedence for air-to-ground
radio control over the runway lighting system which
is set at a predetermined intensity step, based on
expected visibility conditions. Runways without
approach lighting may provide radio controlled
intensity adjustments of runway edge lights. Other
lighting systems, including VASI, REIL, and taxiway
lights may be either controlled with the runway edge
lights or controlled independently of the runway edge
lights.
b. The control system consists of a 3-step control
responsive to 7, 5, and/or 3 microphone clicks. This
3-step control will turn on lighting facilities capable
of either 3-step, 2-step or 1-step operation. The
3-step and 2-step lighting facilities can be altered in
intensity, while the 1-step cannot. All lighting is
illuminated for a period of 15 minutes from the most
recent time of activation and may not be extinguished
prior to end of the 15 minute period (except for 1-step
and 2-step REILs which may be turned off when
desired by keying the mike 5 or 3 times respectively).
c. Suggested use is to always initially key the mike
7 times; this assures that all controlled lights are
turned on to the maximum available intensity. If
desired, adjustment can then be made, where the
capability is provided, to a lower intensity (or the
REIL turned off) by keying 5 and/or 3 times. Due to
the close proximity of airports using the same
frequency, radio controlled lighting receivers may be
set at a low sensitivity requiring the aircraft to be
relatively close to activate the system. Consequently,
even when lights are on, always key mike as directed
when overflying an airport of intended landing or just
prior to entering the final segment of an approach.
This will assure the aircraft is close enough to activate
the system and a full 15 minutes lighting duration is
available. Approved lighting systems may be
activated by keying the mike (within 5 seconds) as
indicated in
TBL 2-1-3.
TBL 2-1-3
Radio Control System
Key Mike
|
Function
|
7 times within 5 seconds
|
Highest intensity available
|
5 times within 5 seconds
|
Medium or lower intensity
(Lower REIL or REIL-off)
|
3 times within 5 seconds
|
Lowest intensity available
(Lower REIL or REIL-off)
|
d. For all public use airports with FAA standard
systems the Airport/Facility Directory contains the
types of lighting, runway and the frequency that is
used to activate the system. Airports with IAPs
include data on the approach chart identifying the
light system, the runway on which they are installed,
and the frequency that is used to activate the system.
NOTE-
Although the CTAF is used to activate the lights at many
airports, other frequencies may also be used. The
appropriate frequency for activating the lights on the
airport is provided in the Airport/Facility Directory and
the standard instrument approach procedures publications. It is not identified on the sectional charts.
e. Where the airport is not served by an IAP, it may
have either the standard FAA approved control
system or an independent type system of different
specification installed by the airport sponsor. The
Airport/Facility Directory contains descriptions of
pilot controlled lighting systems for each airport
having other than FAA approved systems, and
explains the type lights, method of control, and
operating frequency in clear text.
2-1-9. Airport/Heliport Beacons
a. Airport and heliport beacons have a vertical
light distribution to make them most effective from
one to ten degrees above the horizon; however, they
can be seen well above and below this peak spread.
The beacon may be an omnidirectional capacitor-discharge device, or it may rotate at a constant speed
which produces the visual effect of flashes at regular
intervals. Flashes may be one or two colors
alternately. The total number of flashes are:
1. 24 to 30 per minute for beacons marking
airports, landmarks, and points on Federal airways.
2. 30 to 45 per minute for beacons marking
heliports.
b. The colors and color combinations of beacons
are:
1. White and Green- Lighted land airport.
2. *Green alone- Lighted land airport.
3. White and Yellow- Lighted water airport.
4. *Yellow alone- Lighted water airport.
5. Green, Yellow, and White- Lighted heliport.
NOTE-
*Green alone or yellow alone is used only in connection
with a white-and-green or white-and-yellow beacon
display, respectively.
c. Military airport beacons flash alternately white
and green, but are differentiated from civil beacons
by dualpeaked (two quick) white flashes between the
green flashes.
d. In Class B, Class C, Class D and Class E surface
areas, operation of the airport beacon during the hours
of daylight often indicates that the ground visibility
is less than 3 miles and/or the ceiling is less than
1,000 feet. ATC clearance in accordance with
14 CFR Part 91 is required for landing, takeoff and
flight in the traffic pattern. Pilots should not rely
solely on the operation of the airport beacon to
indicate if weather conditions are IFR or VFR. At
some locations with operating control towers, ATC
personnel turn the beacon on or off when controls are
in the tower. At many airports the airport beacon is
turned on by a photoelectric cell or time clocks and
ATC personnel cannot control them. There is no
regulatory requirement for daylight operation and it
is the pilot's responsibility to comply with proper
preflight planning as required by 14 CFR
Section 91.103.
2-1-10. Taxiway Lights
a. Taxiway Edge Lights. Taxiway edge lights are
used to outline the edges of taxiways during periods
of darkness or restricted visibility conditions. These
fixtures emit blue light.
NOTE-
At most major airports these lights have variable intensity
settings and may be adjusted at pilot request or when
deemed necessary by the controller.
b. Taxiway Centerline Lights. Taxiway centerline lights are used to facilitate ground traffic under
low visibility conditions. They are located along the
taxiway centerline in a straight line on straight
portions, on the centerline of curved portions, and
along designated taxiing paths in portions of
runways, ramp, and apron areas. Taxiway centerline
lights are steady burning and emit green light.
c. Clearance Bar Lights. Clearance bar lights
are installed at holding positions on taxiways in order
to increase the conspicuity of the holding position in
low visibility conditions. They may also be installed
to indicate the location of an intersecting taxiway
during periods of darkness. Clearance bars consist of
three in-pavement steady-burning yellow lights.
d. Runway Guard Lights. Runway guard lights
are installed at taxiway/runway intersections. They
are primarily used to enhance the conspicuity of
taxiway/runway intersections during low visibility
conditions, but may be used in all weather conditions.
Runway guard lights consist of either a pair of
elevated flashing yellow lights installed on either side
of the taxiway, or a row of in-pavement yellow lights
installed across the entire taxiway, at the runway
holding position marking.
NOTE-
Some airports may have a row of three or five in-pavement
yellow lights installed at taxiway/runway intersections.
They should not be confused with clearance bar lights
described in paragraph
2-1-9c, Clearance Bar Lights.
e. Stop Bar Lights. Stop bar lights, when
installed, are used to confirm the ATC clearance to
enter or cross the active runway in low visibility
conditions (below 1,200 ft Runway Visual Range). A
stop bar consists of a row of red, unidirectional,
steady-burning in-pavement lights installed across
the entire taxiway at the runway holding position, and
elevated steady-burning red lights on each side. A
controlled stop bar is operated in conjunction with the
taxiway centerline lead-on lights which extend from
the stop bar toward the runway. Following the ATC
clearance to proceed, the stop bar is turned off and the
lead-on lights are turned on. The stop bar and lead-on
lights are automatically reset by a sensor or backup
timer.
CAUTION-
Pilots should never cross a red illuminated stop bar, even
if an ATC clearance has been given to proceed onto or
across the runway.
NOTE-
If after crossing a stop bar, the taxiway centerline lead-on
lights inadvertently extinguish, pilots should hold their
position and contact ATC for further instructions.
|