时间：2011-04-18 00:47来源：蓝天飞行翻译 作者：航空 点击：次
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2.Ground equipment consists of a transponder interrogator, sensor arrays to detect lateral and vertical position, and ILS frequency transmitters. The TLS detects the aircraft’s position by interrogating its transponder. It then broadcasts ILS frequency signals to guide the aircraft along the desired approach path. 3.TLS instrument approach procedures are designated Special Instrument Approach Procedures. Special aircrew training is required. TLS ground equipment provides approach guidance for only one aircraft at a time. Even though the TLS signal is received using the ILS receiver, no fixed course or glidepath is generated. The concept of operation is very similar to an air traffic controller providing radar vectors, and just as with radar vectors, the guidance is valid only for the intended aircraft. The TLS ground equipment tracks one aircraft, based on its transponder code, and provides correction signals to course and glidepath based on the position of the tracked aircraft. Flying the TLS corrections com-puted for another aircraft will not provide guidance relative to the approach; therefore, aircrews must not use the TLS signal for navigation unless they have received approach clearance and completed the required coordination with the TLS ground equip-ment operator. Navigation fixes based on conventional NAVAIDs or GPS are provided in the special instrument approach procedure to allow aircrews to verify the TLS guidance. d. Special Category I Differential GPS (SCAT.I DGPS)1. The SCAT.I DGPS is designed to provide approach guidance by broadcasting differential correction to GPS. 2.SCAT.I DGPS procedures require aircraft equipment and pilot training. 3.Ground equipment consists of GPS receivers and a VHF digital radio transmitter. The SCAT.I DGPS detects the position of GPS satellites relative to GPS receiver equipment and broadcasts differen-tial corrections over the VHF digital radio. 4.Category I Ground Based Augmentation System (GBAS) will displace SCAT.I DGPS as the public use service. REFERENCE. AIM, Para 5.4.7f, Instrument Approach Procedures. 1.1.42 Navigation Aids Section 2. Area Navigation (RNAV) and Required Navigation Performance (RNP)1.2.1. Area Navigation (RNAV)a. General. RNAV is a method of navigation that permits aircraft operation on any desired flight path within the coverage of ground or space based navigation aids or within the limits of the capability of self.contained aids, or a combination of these. In the future, there will be an increased dependence on the use of RNAV in lieu of routes defined by ground.based navigation aids. RNAV routes and terminal procedures, including departure procedures (DPs) and standard terminal arrivals (STARs), are designed with RNAV systems in mind. There are several potential advantages of RNAV routes and procedures: 1. Time and fuel savings, 2. Reduced dependence on radar vectoring, altitude, and speed assignments allowing a reduction in required ATC radio transmissions, and 3. More efficient use of airspace. In addition to information found in this manual, guidance for domestic RNAV DPs, STARs, and routes may also be found in Advisory Circu-lar 90.100A, U.S. Terminal and En Route Area Navigation (RNAV) Operations. b. RNAV Operations. RNAV procedures, such as DPs and STARs, demand strict pilot awareness and maintenance of the procedure centerline. Pilots should possess a working knowledge of their aircraft navigation system to ensure RNAV procedures are flown in an appropriate manner. In addition, pilots should have an understanding of the various waypoint and leg types used in RNAV procedures; these are discussed in more detail below. 1. Waypoints. A waypoint is a predetermined geographical position that is defined in terms of latitude/longitude coordinates. Waypoints may be a simple named point in space or associated with existing navaids, intersections, or fixes. A waypoint is most often used to indicate a change in direction, speed, or altitude along the desired path. RNAV procedures make use of both fly.over and fly.by waypoints. (a)Fly.by waypoints. Fly.by waypoints are used when an aircraft should begin a turn to the next course prior to reaching the waypoint separating the two route segments. This is known as turn anticipation. (b)Fly.over waypoints. Fly.over way-points are used when the aircraft must fly over the point prior to starting a turn. NOTE. FIG 1.2.1 illustrates several differences between a fly.by and a fly.over waypoint. FIG 1.2.1 Fly.by and Fly.over Waypoints 2. RNAV Leg Types. A leg type describes the desired path proceeding, following, or between waypoints on an RNAV procedure. Leg types are identified by a two.letter code that describes the path (e.g., heading, course, track, etc.) and the termination point (e.g., the path terminates at an altitude, distance, fix, etc.). Leg types used for procedure design are included in the aircraft navigation database, but not normally provided on the procedure chart. The narrative depiction of the RNAV chart describes how a procedure is flown. The “path and terminator concept” defines that every leg of a procedure has a termination point and some kind of path into that termination point. Some of the available leg types are described below. Area Navigation (RNAV) and Required Navigation Performance (RNP) 1.2.1 (a) Track to Fix. A Track to Fix (TF) leg is (b) Direct to Fix. A Direct to Fix (DF) leg is intercepted and acquired as the flight track to the a path described by an aircraft’s track from an initial following waypoint. Track to a Fix legs are area direct to the next waypoint. Narrative: “left sometimes called point.to.point legs for this reason. turn direct BARGN WP.” See FIG 1.2.3. Narrative: “on track 087 to CHEZZ WP.” See FIG 1.2.2. |
