AAP Reduced engine operations With most operators now encouraging or mandating crew to make use of reduced-engine taxi arrivals, there is an added threat that it can be difficult to regain momentum with one or more engines shut down particularly if the aircraft has insufficient space to move forward on the taxiway centreline prior to the sharp turn onto stand. Crew should be aware of this when considering if it is an appropriate action. On occasion, because of stand design, the guidance system can be obscured by the jet bridge until almost perpendicular to the centreline of the stand. Some systems are also affected by certain weather conditions, such as mist or fog, in accordance with airline specific SOPs. In the event that the restarting of an engine is required, crews need to apply solid threat and error management to what is an unusual situation with significant perceived time pressures. Where would I find details of an airports procedure if guidance is not available? Most airlines do not use the AIP during operations; most use a third-party chart provider (such as Jeppesen, Lido or Navtech). These present the information from the AIP to the crew. In the case of Lido, the AOI (Airport Operational Information) tab in the General section Apron Restrictions provides details of actions in case stand guidance is not activated. No specific system is available that is designed to prevent GCOLs Are there any ground handling implications of turning onto stand before the guidance system has been activated? Before the guidance is activated, the ground crew is responsible for carrying out an FOD check of the stand area. This involves walking along the centreline of the stand to check for debris. If the aircraft has already started approaching the stand, this increases risk to ground crew and may make an effective FOD check impossible. It should also be remembered that in the event stand guidance suffers a total failure or the delay waiting for ground crew is unknown crew should not feel rushed to clear the taxiway. Waiting for an extended period for a marshaller to become available is preferable to attempting to self-position onto a stand that is not designed for self-parking. Are there any systems available on commercial aircraft or at airports to help avoid ground collisions? Currently, no specific system (such as TCAS or GPWS) is available that is designed to prevent ground collisions. Some aircraft do have camera systems installed on the tail of the aircraft that can be viewed by the flight crew, enhancing situational awareness. There are, however, limitations, as on some types the wingtips of the aircraft are not visible. The latest versions of A-VDGS parking systems, using lasers, build a picture of the entire stand environment and are designed to issue a stop signal if the system detects a possible collision. Crew should be aware that no stand guidance system is faultless. If there is any doubt about the guidance being provided, stop and hold position until clearance from obstacles can be assured. The Accident Analysis and Prevention study group is always available to support any member involved in a GCOL incident, and can be contacted via the BALPA 24-hour Emergency Line on 020 8476 4099. 18 THE LOG Spr 24 pp16-18 AAP Ground Ops.indd 18 16/02/2024 11:31