时间：2011-04-18 00:47来源：蓝天飞行翻译 作者：航空 点击：次
|
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 Airport Lighting Aids 2.1.5 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). Touch-down 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. Taxi-way 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 sys-tem (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. Taxi-way 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/micro-wave 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 2.1.10.)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 information to pilots and surface vehicle operators to indicate when it is unsafe to enter, cross, takeoff from, or land on a runway. The RWSL system processes information from surveillance systems and activates Runway Entrance Lights (REL), Takeoff Hold Lights (THL), and Final Approach Runway Occupancy Signal (FAROS) in accordance with the motion and velocity of the detected traffic. REL and THL are in-pavement light fixtures that are directly visible to pilots and surface vehicle operators. FAROS activation is by means of flashing the Precision Approach Path Indicator (PAPI). RWSL is an independent safety enhance-ment that does not substitute for an ATC clearance. Clearance to enter, cross, takeoff from, land on, or operate on a runway must be issued by ATC. Although ATC has limited control over the system, personnel do not directly use, and may not be able to view, light fixture output in their operations. 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 and directed toward the pilot at the hold line. A specific array of REL lights include the first light at the hold line followed by a series of evenly spaced lights to the runway edge; and one additional light at the runway centerline in line with the last two lights before the runway edge (See FIG 2.1.9). When activated, these red lights indicate that there is high speed traffic on the runway or there is an aircraft on final approach within the activation area. |
