7.7 Taxing in low visibility conditions:
The attention of pilot is drawn to the increased ground collision risk that might occur when aircraft are taxied in low visibility conditions. Experience show that traffic flow rates on taxiways can be conducted safety in aerodrome visibility down to approx. 500m. However, when the visibility is below 500 m, the safe ground maneuvering of the aircraft demands special care and alertness by the crew, with an awareness of the difficulties, which may be encountered. Close co-operation between the crew and ATC is essential from first entering taxiways until parked or taken-off. Do not hesitate to request the assistance of a “Follow me” car. Some useful guidelines are given below: The greater risk when taxing is likely to occur after landing when crews are known to relax their concentration and alertness, and especially so following a low visibility landing. Crews should note that the reported RVR values may not be representative of the general level of visibility at the airfield and taxi speed should allow for sudden or very rapid reduction in visibility. It should also be noted that taxi-way marking, signs, signals and lighting systems throughout the world are not standardized. Like wise, terminology and nomenclature varies from one regulating authority to another and may even be different within the jurisdiction of a particular authority. It is therefore essential that crews make a careful note of the taxi instructions given and that the read back is acknowledged.
Before taxing the crew should ensure that the intended routing clearance passed is acknowledged, make full use of the aircraft compass, airfield chart and low visibility route chart when available. When approaching the runway in use, the crew must ensure that the category II/III holding point is not passed, bearing in mind that the green taxi way central line lights may be illuminated beyond the holding point if it does not coincide with a stop bar, or the stop bar may be out because a preceding aircraft is lining up. After landing, when the aircraft has vacated the runway, the taxi way should not be entered until contact has been made with the appropriate ground movement control, and instructions given are acknowledged. If in doubt, in all cases stop and request further guidance or instructions from ATC before proceeding. If available, make full use of ATC ground radar. During taxing in poor visibility, ensure that flight deck checks and drills do not conflict with the need to maintain a good look out. If necessary, carry out the majority of taxi checklist items at, or just before, approaching the holding point. Keep track of the aircraft positions at all times and monitor R/T transmissions in order to determine the position of other aircraft and vehicles on the airfield. Where a choice of taxi route is presented, the pilot taxing should given the other crew members notice of his intentions, so that the routing can be confirmed and closely monitored. Prior to a turn, careful lookout should be made in both directions. 中国航空网 www.aero.cn 航空翻译 www.aviation.cn 本文链接地址：CAT II/ III A/ III B TRAINING MANUAL 培训手册(23)
