Description

On 26 July 2014 a Boeing 717-200 (VH-NXL) being operated by National Jet Systems for QantasLink on a scheduled domestic passenger flight from Karratha to Perth made a go around just after touching down on runway 24 at destination in normal daylight ground visibility after the crew saw a vehicle ahead and facing away from them on the runway centreline. The aircraft just cleared the vehicle, whose driver was unaware of the proximity of the aircraft until that point. The subsequent repositioning for a further approach was followed by an uneventful landing.

Investigation

An Investigation was carried out by the Australian Transport Safety Bureau (ATSB). It was found that intersecting runways 21 and 24 had been in use at the time and that a heavy shower was clearing the airport just prior to the conflict occurring.

The 717 had been cleared for an ILS approach to runway 24; the Captain was PF. Just after this, a new controller took over the TWR position and soon afterwards, the 717 checked in on TWR frequency. The new controller, noticing that the strip for the aircraft was annotated '21' changed it to '24'. He then cleared an A330 to land on runway 21. At about the same time, an airport operator vehicle called in position at the holding point for runway 24 on taxiway 'W' (near the landing threshold) awaiting entry to carry out a routine runway inspection. The TWR controller cleared the vehicle to enter runway 24 but hold short of runway 21 and wrote "S2" (the vehicle callsign was Safety 2) on the console runway strip to indicate that the runway was occupied. At that time, the 717 had 7.5nm to run for runway 24; neither of its pilots recalled hearing the vehicle clearance.

The vehicle began to proceed along runway 24 in the direction of use, eventually arriving at the holding point prior to the intersection with runway 21. The A330 landed on runway 21 and, once it had vacated, the TWR controller cleared an FOKKER F100 to take off. Whilst simultaneously observing the F100 get airborne, the TWR controller then scanned runway 24 without seeing the vehicle on it, picked up the strip for the 717 and put it in the console runway bay without noticing the vehicle strip also there. With the 717 now at a range of about 1.5nm (although still in cloud at that time), he gave it a landing clearance. The Vehicle Driver subsequently advised that they had heard this clearance but not the assigned runway and had assumed the aircraft would land on runway 21.

As the 717 touched down on runway 24 approximately 370 metres from the threshold, the First Officer saw the flashing lights of a vehicle ahead on the runway, immediately called "go rround, car on the runway" and the Captain commenced a go-around. The aircraft became airborne again after about 6 seconds and a ground roll of about 370 metres. At this time, the safety vehicle was still stopped on the centreline of runway 24 about 1180 metres from the threshold and facing away from the approaching aircraft. The vehicle driver did not see the aircraft until it had passed about 150 feet over his vehicle and promptly queried what had happened. Shortly afterwards, the TWR controller was relieved. The sequence of events is shown on the annotated runway diagram below:

The Investigation found that routine runway inspections such as the one involved in this incident were programmed five times each day. It was further found that until May 2014, FOD inspections such as the one being carried out were always conducted by a vehicle driving along any active runway in the opposite direction to that in use. However, following a request at that time from ANSP Airservices Australia "to expedite runway inspections by operating with the flow of aircraft traffic", the airport operator had asked Airside Operations Managers conducting runway inspections to do so "with the flow of aircraft where possible to increase efficiency". Since then, it was found that FOD inspections had routinely been conducted in the direction of active runway use.

It was noted that the fact that the vehicle was facing away from the landing aircraft and stationary on the white runway 24 centreline markings had made it very difficult for the 717 pilots to see. The First Officer advised that he started looking down the runway when the aircraft was at about 30 feet agl and only saw the vehicle as the main landing gear touched down.

The 717 Captain commented to the Investigation that had they selected reverse thrust, which is usually done as soon as the aircraft has touched down, they would have been committed to completing a landing. He also noted that his First Officer had been highly experienced which may have assisted in his sighting the vehicle and reacting quickly. He considered that the incident "provided a very good example of the value of flight crew knowing their role as pilot flying or pilot monitoring explicitly and maintaining a good awareness of their environment".

Safety Action intended by Airservices Australia "in response to the occurrence" was noted to include:

• the introduction of Advanced Surface Movement Guidance and Control System at Adelaide which would have generated an alert indicating conflict between an aircraft on short final and a vehicle on the landing runway.

• the introduction of an Integrated Tower Automation Suite (INTAS) which will combine flight and operational data, surveillance and voice communications into a single integrated tower-specific layout and replace the existing manual air traffic control system. Had INTAS been available at the time of this incident, it was stated that the controller would still have been able to allocate the electronic flight strip assigned to the aircraft in the runway bay with the vehicle strip already there, but an alarm would have been triggered.

Safety Action intended by the Airport Operator "in response to the occurrence" was noted to include:

• the introduction of human factors training for Safety Officers which will include a specific focus on relationships with ATC and situational awareness.
• a review the need for a dedicated radio channel for Safety Officers to use when operating on or crossing runways.
• the company radio frequency is to be switched off during runway operations.
• the suitability of vehicle lighting for runway operations is to be reassessed.
• all runway inspections will in future be performed facing oncoming traffic.
• the types, frequency, methods and timing of runway inspections will be reviewed.
• technology that minimises vehicle runway entry and occupancy requirements will be investigated.
• runway inspection techniques used at other airports will be reviewed.

The Final Report was released on 26 February 2015. No Safety Recommendations were made.

Related Articles

• Runway Incursion
• Situational Awareness
• Rejected Landings
• ATC Radio Use by Airside Vehicles
• Advanced Surface Movement Guidance and Control System (A-SMGCS)
• Surface Movement Radar
• Cross-checking Process
• The Human Factors "Dirty Dozen"