时间:2011-04-18 00:47来源:蓝天飞行翻译 作者:航空 点击:次
1.1.8. Navigational Aid (NAVAID) Service Volumes a.Most air navigation radio aids which provide positive course guidance have a designated standard service volume (SSV). The SSV defines the reception limits of unrestricted NAVAIDs which are usable for random/unpublished route navigation. b.A NAVAID will be classified as restricted if it does not conform to flight inspection signal strength and course quality standards throughout the published SSV. However, the NAVAID should not be considered usable at altitudes below that which could be flown while operating under random route IFR conditions (14 CFR Section 91.177), even though these altitudes may lie within the designated SSV. Service volume restrictions are first published in Notices to Airmen (NOTAMs) and then with the alphabetical listing of the NAVAIDs in the A/FD. c.Standard Service Volume limitations do not apply to published IFR routes or procedures. d.VOR/DME/TACAN Standard Service Volumes (SSV). 1. Standard service volumes (SSVs) are graphi-cally shown in FIG 1.1.1, FIG 1.1.2, FIG 1.1.3, FIG 1.1.4, and FIG 1.1.5. The SSV of a station is indicated by using the class designator as a prefix to the station type designation. EXAMPLE. TVOR, LDME, and HVORTAC. 1.1.4 Navigation Aids FIG 1.1.1 FIG 1.1.2 Standard High Altitude Service Volume Standard Low Altitude Service Volume (See FIG 1.1.5 for altitudes below 1,000 feet). (See FIG 1.1.5 for altitudes below 1,000 feet). 40 NM 60,000 ft. 18,000 ft. 130 NM 45,000 ft. 18,000 ft. 1,000 ft. 14,500 ft. NOTE: All elevations shown are with respect to the station’s site elevation (AGL). Coverage is not available in a cone of airspace directly above the facility. FIG 1.1.3 Standard Terminal Service Volume (See FIG 1.1.4 for altitudes below 1,000 feet). Navigation Aids 1.1.5 2. Within 25 NM, the bottom of the T service 1. NDBs are classified according to their volume is defined by the curve in FIG 1.1.4. Within intended use. 40 NM, the bottoms of the L and H service volumes are defined by the curve in FIG 1.1.5. (See 2. The ranges of NDB service volumes are TBL 1.1.1.)shown in TBL 1.1.2. The distances (radius) are the e. Nondirectional Radio Beacon (NDB) same at all altitudes. TBL 1.1.1 VOR/DME/TACAN Standard Service Volumes SSV Class Designator Altitude and Range Boundaries T (Terminal) . From 1,000 feet above ground level (AGL) up to and including 12,000 feet AGL at radial distances out to 25 NM. L (Low Altitude) . From 1,000 feet AGL up to and including 18,000 feet AGL at radial distances out to 40 NM. H (High Altitude) . From 1,000 feet AGL up to and including 14,500 feet AGL at radial distances out to 40 NM. From 14,500 AGL up to and including 60,000 feet at radial distances out to 100 NM. From 18,000 feet AGL up to and including 45,000 feet AGL at radial distances out to 130 NM. TBL 1.1.2 NDB Service Volumes Class Distance (Radius)Compass Locator 15 NM MH 25 NM H 50 NM* HH 75 NM *Service ranges of individual facilities may be less than 50 nautical miles (NM). Restrictions to service volumes are first published as a Notice to Airmen and then with the alphabetical listing of the NAVAID in the A/FD. FIG 1.1.4 Service Volume Lower Edge Terminal 1000 500 0 0 5 10152025 DISTANCE TO THE STATION IN NM Navigation Aids 1.1.6 FIG 1.1.5 Service Volume Lower Edge Standard High and Low 1.1.9. Instrument Landing System (ILS)a. General 1.The ILS is designed to provide an approach path for exact alignment and descent of an aircraft on final approach to a runway. 2.The ground equipment consists of two highly directional transmitting systems and, along the approach, three (or fewer) marker beacons. The directional transmitters are known as the localizer and glide slope transmitters. 3.The system may be divided functionally into three parts: (a)Guidance information: localizer, glide slope; (b)Range information: marker beacon, DME; and (c)Visual information: approach lights, touchdown and centerline lights, runway lights. 4.Precision radar, or compass locators located at the Outer Marker (OM) or Middle Marker (MM), may be substituted for marker beacons. DME, when specified in the procedure, may be substituted for the OM. 5.Where a complete ILS system is installed on each end of a runway; (i.e., the approach end of Runway 4 and the approach end of Runway 22) the ILS systems are not in service simultaneously. b. Localizer 1. The localizer transmitter operates on one of 40 ILS channels within the frequency range of 108.10 to 111.95 MHz. Signals provide the pilot with course guidance to the runway centerline. 2.The approach course of the localizer is called the front course and is used with other functional parts, e.g., glide slope, marker beacons, etc. The localizer signal is transmitted at the far end of the runway. It is adjusted for a course width of (full scale fly.left to a full scale fly.right) of 700 feet at the runway threshold. 3.The course line along the extended centerline of a runway, in the opposite direction to the front course is called the back course. CAUTION. Unless the aircraft’s ILS equipment includes reverse sensing capability, when flying inbound on the back course it is necessary to steer the aircraft in the direction opposite the needle deflection when making corrections from off.course to on.course. This “flying away from the needle” is also required when flying outbound on the front course of the localizer. Do not use back course signals for approach unless a back course approach procedure is published for that particular runway and the approach is authorized by ATC. |