Airfield lighting

Decennial sensors detect movements of aircraft and there vehicles on the ground. The signals from individual lights and sensors are communicated via FALL and are comprehensively visualized for the operators in the tower through an ALAS. FALL enables the controllers to optimize the use of the entire airfield lighting system: through flexible control of each segment of the runway, taxiway and apron circuits, every component and individual lamp is exactly controllable.As such, FALL provides excellent tools to perform control of aircraft ground movements: taxiway routing, Stoppard control, runway incursion detection are now available for the operators in the tower. Safety of air traffic movements and number of slots per day are significantly increased with this modern and reliable control system. Using the power supply series circuit for reliable and high-speed communication between substation and individual lamps, FALL detects and supervises the actual status of each lamp and provides c omplete detailed information to the operational control station.FALL continuously monitors all lamps controlled via the system and identifies a lamp failure immediately, indicating the exact position of the failed lamp. As a result, the need for regular visual inspections is reduced and overall maintenance performance can be improved. In order to prevent collisions on the reside movement area, CIAO prescribes the implementation of an (Advanced) Surface Movement Guidance and Control System) – (A)SMOCKS is a modern control and monitoring system for the guidance of aircraft on the ground.The solutions offered by Siemens Intelligent Traffic Systems Airfield meet all legal and operational requirements in this field of application. Thanks to sophisticated navigational aids for air traffic control, aircraft can take off and land under almost all weather conditions. However, when traffic on the ground is lowed down, high-volume airborne operations are put in Jeopardy: Visibility cond itions of less than mm generally delay aircraft ground movements and reduce the total capacity of the airport.SUMS identifies each aircraft, provides continuous surveillance and monitoring of taxiing traffic; determines conflict-free taxiway routes automatically and uses visual signals to guide aircraft and vehicles reliably. And in case of route deviations, it warns pilots or drivers immediately. The comprehensive SMOCKS control and monitoring functionality provides controllers with tools to enhance airport safety, efficiency and availability – under all visibility conditions.Tower ALAS Airfield Lighting Control and Monitoring Systems Airfield Lighting Control Systems (ALAS) allow air traffic controllers (TACT) to monitor and operate a range of lighting functions from the control tower, at the same time providing them with valuable feedback on the performance status of system lighting equipment. Surface Movement Guidance and Control System CIAO has specified the provision of (advanced) surface movement guidance and control systems (A-)SMOCKS to avoid collisions on the ground. Siemens/DAB is doing its part to help airports to fulfill these requirements.In the late asses the problems of transition from the new precision radio instrument approach aids to the final, visual approach at night or in reduced visibility much exercised civil aviation. Various high-intensity approach lighting systems were developed to ease the transition from instrument to visual flight. In 1949 three competing systems – a British one (the Calvert system), a French one (a form of displaced Calvert system) and an American one (the Slope Line system) were presented to CIAO. Because each system had its supporters among the CIAO members, CIAO ended up recommending that any of the three systems could be adopted.Independently, and before the CIAO decision, DACCA engineers had also been studying the problem of approach lighting and had concluded that the British ‘Calvert' s ystem was superior. A trial installation was installed on Session's Runway 08 toward the end of 1951. This trial proved successful and the system was commissioned for operational use in 1953. The following information about the Calvert cross bar lighting system is based on an article High Intensity Approach Lighting by S W Hart (DACCA Sectional Airways Engineer) which appeared in the Civil Aviation Joanna, the Dacca house publication, Volvo 1, No 3, March 1951.In 1946 Mr. E S Calvert of the Royal Aircraft Establishment, Breakthrough, was requested by a UK Ministry of Civil Aviation Airfield Lighting Committee to investigate the problem of approach lighting and establish the general principles involved. Calvert tackled the problem by attempting to ascertain the visual and mental processes by which a pilot lands an aircraft. He then developed a theoretical model by which different lighting systems could be compared, and tested his theoretical results using simulation.Culvert's line of reasoning led him to the conclusion that to provide smooth transition room instrument to visual flying without optical illusions, and to provide sensitive and natural indications which could easily be interpreted by the average pilot, the approach lighting pattern should consist of a centre line of light with horizontal bars basic elements – a line of lights leading to the runway threshold, and horizontal lights to define the attitude of the aircraft. Calvert placed much stress on roll guidance compared with the Americans who, up to that time, had completely neglected it.He was the first to realism that it was easy to confuse lateral displacement with angle of ann.. The Calvert system does not indicate a defined glide path, but the widths of the horizon bars are such that, if a pilot maintains a glide that will take him to the correct touch down point, each bar will appear to be the same width as the previous one as it disappears under the nose of the aircraft. Distance is i ndicated by using single lights in the centre line to indicate 1000 Ft or less from the threshold, double lights for 1000-2000 Ft and triple lights for 2000-3000 Ft.It is interesting to note that the basic form of the Calvert cross bar lighting system still forms the basis for high- intensity approach lighting systems today. Diagrams above: With horizon bars the pilot can see if he is on an even keel (left) or banked right wing down to turn on to the centre line (right). Below: A modified form of the basic High Intensity Approach Lighting system is used on some capital city precision approach (ILLS) runways, in this case on Melbourne/Utilitarian's Runway 27.The main difference is the larger array of lights Just prior to the threshold. 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 they are capable of producing: High Intensity Runway Lights (HIRE) Medium Intensity Runway Lights (MARL) Low Intensity Runway Lights (LIRA) The HIRE and MARL systems have variable intensity controls, whereas the Liars normally have one intensity setting.Runway Edge Lights are white, except on instrument runways where yellow replaces white on the last 2,000 feet or half the runway length, whichever is less, to form a caution zone for landings. 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. Lighting (ARC) or Pilot Activated Lighting (PAL), is a technical system by which aircraft pilots can control the lighting of an airport or airfield's, approach lights, runway edge lights, and taxiways via radio.PC systems are most common at non- towered or little-used airfields where it is not economical to light the runways all night every night nor to maintain staff to turn the runway lightin g on and off as needed. PC enables pilots to control the lighting only when they require it, thereby saving electricity and reducing light pollution. If the airfield supports PC, the pilot test the radio to the ARC frequency for the airport, which is often, but not always, the same as the UNISOM/ACTA frequency (e. . Smiths Falls-Montague Airport hosts separate Unisom and ARC frequencies). The systems are then typically operated by performing a series of clicks with the radio microphone talk button. PC systems most often have three settings: Low intensity: Three clicks within seven seconds Medium intensity: Five clicks within seven seconds High intensity: Seven clicks within seven seconds When the lighting system is activated, a 15-minute countdown starts, after which the sights turn off.While the lights are still active, whenever a lighting command is issued, whether it changes the lighting intensity or not, the 15-minute countdown is reset. At some airfields, special lights may bli nk for ten seconds to warn pilots before the lights shut off. When using PC, it is very highly recommended that aircraft on final approach to the airfield issue a fresh lighting command even if the lights are already on (especially if the lights were activated by another aircraft). This is so that the lighting does not go off by surprise at a critical moment (such as when crossing he runway threshold).The Visual Approach Slope Indicator (VASS) is a system of lights on the side of an airport runway that provides visual descent guidance information during the approach to a runway. These lights may be visible from up to eight kilometers (five miles) during the day and up to 32 kilometers (20 miles) or more at night. Contents [hide] 1 Types 1. 1 Standard VASS 1. 2 API (Precision Approach Path Indicator) 1. 3 PASS' (Pulsating Visual Approach Slope Indicator) 1. 4 Trio-colored VASS 2 Mnemonics 3 Reference 4 See also 5 External links [edit] Types Standard Visual Approach Slope IndicatorBas ic visual approach slope indicators consist of two sets of lights. One set marks the start of the runway, while the other is set up some seven meters (twenty feet) along the runway. Each set of lights is designed so that the lights appear as either white or red, depending on the angle at which the lights are viewed. When the pilot is approaching the lights at the proper angle, meaning he is on the glide slope, the first set of lights appears white and the second set appears red.When both sets appear white, he is flying too high, and when both appear red he is flying too low. This is the cost common type of visual approach slope indicator system. [edit] API (Precision Approach Path Indicator) Main article: Precision Approach Path Indicator Precision Approach Path Indicator consist of four sets of lights in a line perpendicular to the runway, usually mounted to the left side of the runway. These have a similar purpose to basic visual approach slope indicators, but the additional light s serve to show the pilot how far off the glide slope the aircraft is.When the lights show White- White-Red-Red the aircraft is on the correct glide slope for landing, usually 3. 00. Three red lights (White-Red-Red-Red) indicate that the aircraft is slightly below glide slope (2. 80), while four red lights (Red-Red-Red-Red) indicate that the aircraft is significantly below glide slope (3. 50). Most large airports utilize this system. Although most airports use a API based on a 3. 00 glide slope, some airports may use a glide slope as great as 4. 50 in order to have proper obstruction clearance. Edit] PASS' (Pulsating Visual Approach Slope Indicator) This is a single light next to the runway. The signal format is solid white when established on the proper descent profile, and solid red when below the proper scent profile. An actively pulsing red or white light when well above or well below allows the pilot to determine his position in the signal format and what corrective action is n eeded to return to the proper descent profile. [edit] Trio-colored VASS This is a single light that appears amber above the glide slope, green on the glide slope and red below it.It is rarely used, partly because pilots who are unfamiliar with them have been known to misinterpret the lights, causing them to ‘correct' in the wrong direction. [edit] Mnemonics Older Visual Approach Slope Indicator Pilots often use mnemonics to help them remember basic information. In English, the following are common: Red over white, you're all right. White over white, you're out of sight. Alternative: White over white, you'll fly all night. Alternative: White over white, you're high as a kite. Alternative: White over white, you remain in flight. Red over red, you're dead.Alternative: Red over red, watch your head. Also Red red you're dead Red and white you're alright White and white you're as high as a kite Runway End Identifier Lights (REEL) are installed at many airports to provide rapid and p ositive 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. Reels may be either unidirectional or unidirectional facing the approach area. They are effective for: Identification of a runway surrounded by a preponderance of other lighting.Identification of a runway which lacks contrast with surrounding terrain. Identification of a runway during reduced visibility. An approach lighting system, or ALLS, is a lighting system installed on the approach end of an airport runway and consists of a series of lighters, strobe lights, or a ambition of the two that extends outward from the runway end. ALLS usually serves a runway that has an instrument approach procedure (PAP) associated with it and allows the pilot to visually identify the runway environment once he or she has arrived at a prescribed point on an approach.The runway lighting is controlled by the air traffi c control tower. At uncontrolled airports, Pilot Controlled Lighting may be installed which can be switched on by the pilot via radio. In both cases, the brightness of the lights can be adjusted for day and night operations. A key ingredient of all Approach Lighting Systems in the US is the Decision Bar. The Decision Bar is always located 1000†² from the threshold, and it serves as a visible horizon to ease the transition from instrument flight to visual flight.It also is situated such that at Decision Altitude, the Decision Bar is Just appearing to pass under the cowling of the plane. Approach Light Systems are designed such that they allow the pilot to quickly and positively identify visibility distances in Instrument meteorological conditions. For example, if the aircraft is at the Middle Marker, and the Middle Marker is located 3600†² from the threshold, the Decision Bar is 2600†² ahead. If the reoccurred calls for at least 1/2 statute mile flight visibility (roug hly 2600†²), spotting the Decision Bar at the marker would indicate enough flight visibility to continue the procedure.In addition, the shorter bars before and after the Decision Bar are spaced either 100†² or 200†² apart depending on the ALLS type. The number of short bars the pilot can see can be used to determine flight visibility. Approaches with lower minimums use the more precision 100†² spacing systems for more accurate identification of visibility. Several ALLS configurations are recognized by the International Civil Aviation Organization (CIAO); however, non-standard ALLS