The pilot of the Cessna 402 (Cessna) had been cleared by the aerodrome controller (ADC) to land on runway 16R at Sydney Kingsford Smith airport. The ADC monitored the aircraft's approach and after landing it was established that the pilot had landed on taxiway Alpha, which was parallel to, and to the right, of runway 16R. There was no other aircraft on taxiway Alpha at the time. The weather was visual meteorological conditions (VMC).
The pilot of the Cessna had approximately 3,000 hours flying experience and had planned to operate an instrument flight rules (IFR) charter flight from Broken Hill to Bankstown via Dubbo. En route the pilot amended the destination to Sydney in an attempt to assist the passengers to connect with their next flight. The pilot had never operated into Sydney but had recently operated into Adelaide and felt that he could self-brief satisfactorily using the Aeronautical Information Publication (AIP) documents. He was familiar with Bankstown but predominantly operated in country areas where, generally, runways had limited or no markings.
Runway 16L was 2483 m long and runway 16R was 3962 m long. Each runway had a parallel taxiway located to the right. Runway 16L was 1037 m to the left of runway 16R and taxiway Alpha was 183 m to the right of runway 16R. Runway 16R threshold was 2,862 m north of the runway 16L threshold. Runway 16R threshold was 497 m north of the intersection of taxiways Alpha and Foxtrot. The colour of the surface of taxiway Alpha changed between taxiways Foxtrot and Golf due to a bitumen/concrete join.
The flight departed Dubbo at 1445 Eastern Standard Time. The pilot tracked via Bindook and was issued with an Odale 2 standard arrival clearance to the aerodrome. He was using the AIP En Route Supplement to assist in orientating himself with the aerodrome layout and made a visual approach to final for runway 16R. He reported that when the aircraft was on the [right] base position he had an uninterrupted view of the area and could see what appeared to be the parallel runways. At the time, the pilot did not appreciate the distance between the runways and the extent of the offset of the runway thresholds. He aligned the aircraft with what he thought was runway 16R, but in fact was taxiway Alpha, with the intention of landing. The ADC issued a landing clearance and as the aircraft passed 1,500 ft on descent the pilot saw a Boeing 747 enter the taxiway he had intended to use. The pilot elected to go around and advised the ADC that he was initiating a go around. The ADC coordinated a clearance with the departure controller and instructed the pilot to turn onto a heading of 170 degrees, to climb to 3,000 ft and to contact the departure controller. The pilot did not query the ADC with respect to the aircraft entering his intended runway as he immediately complied with the instructions and changed to the departure radio frequency.
The ADC saw that the Cessna was high on final and believed that the pilot conducted the go around because the aircraft was too high and did not query the pilot about the approach. The prime means for the ADC to establish aircraft positions was by monitoring aircraft visually. The ADC had an air situation display (ASD), plus access to a surface movement radar (SMR) display to assist in confirming positions of arriving and departing aircraft, and aircraft on the aerodrome. The resolution of both displays was dependent on the selected scale and was also limited, to some extent, by the lateral proximity of runway 16R and taxiway Alpha.
The aircraft was re-sequenced for another visual approach to runway 16R. During the second approach the pilot again aligned the aircraft with what he believed to be runway 16R and subsequently landed on taxiway Alpha.
Runway 16R and taxiway Alpha were marked in accordance with Civil Aviation Safety Authority Rules and Practices for Aerodromes.
Taxiway Alpha had:
- centreline markings, and
- sideline markings.
Runway 16 had:
- threshold markings,
- designation or number (16R) markings,
- centreline and sideline markings,
- fixed distance markings, and
- touchdown zone markings.
Runway 16R was served by an instrument landing system (ILS) navigation aid which provided centerline and glidepath guidance to pilots of aircraft that were fitted with ILS avionics. It also had a T-VASIS that provided a visual approach slope indication. The Cessna was not fitted with an ILS and the pilot was not qualified to conduct an ILS approach. The pilot was instructed by the director controller to report the runway in sight. The pilot reported he had the "aerodrome in sight". The controller did not subsequently query the pilot to confirm that he had the runway in sight. The requirement to report the runway in sight was a function of independent visual approach procedures and was not a runway allocation procedure.
During the second approach, the distance between the Cessna and an aircraft ahead in the approach sequence was reducing and was likely to infringe the required wake turbulence separation standard of 6 NM. The director asked the pilot if he was happy to continue the approach with less than the standard separation. The pilot reported to the director that he was happy to continue. Manual of Air Traffic Services (MATS) procedures required controllers to "ensure that the appropriate wake turbulence minima are applied at the landing threshold" for aircraft on final approach to the same runway. The intention was for only pilots to initiate requests for wake turbulence waivers. Controllers were not to initiate such requests.
It is likely that the pilot was under some self-imposed stress due to the need to ensure that the passengers connected with their next flight. The level of stress probably increased as he attempted to prepare for the arrival and landing at Sydney. Consequently, when he saw what he believed to be the parallel runways he readily accepted that the taxiway was runway 16R despite the significant lateral distances between the parallel runways and also between their respective thresholds.
Confirmation bias occurs when people search for information to confirm what they suspect. People rarely attempt to prove themselves wrong and often disregard information that may contradict their perception of a situation. Despite the pilot referring to an aerodrome diagram, and the lack of runway markings on the selected `runway', he did not comprehend that he was approaching taxiway Alpha instead of runway 16R. It is possible that the pilot's perception, that he had correctly identified runway 16R, was reinforced by the change in contrast of the taxiway surface near the northern end of taxiway Alpha. He may also have been lulled into thinking that the approach was normal, despite the minimal markings on the selected landing area, because of his past experience with runways with little or no markings.
Following the go around, there was an opportunity for the error to be recognised if the pilot had advised the aerodrome controller that an aircraft entered the runway during his approach. Such a comment probably would have caused the controller to query the pilot regarding the runway he had approached. However, during the subsequent go around the pilot had little time to query the aerodrome controller before changing frequency. While being resequenced for the second approach, there was an opportunity for the pilot to query the departure or director controller about the potential hazard he had just experienced. It would have been prudent of the pilot to highlight the situation to at least one of the controllers. The integrity of the aviation system is contingent upon all those involved advising concerns or clarifying situations to maintain safety.
Without an ILS the pilot had limited means, other than ATC, to assist him to confirm that he had positioned the aircraft on the extended centerline for runway 16R.
While the director controller was required to obtain a report from the pilot of having the runway in sight, the provision of that report would not necessarily have prevented the occurrence. The lateral proximity of runway 16R and taxiway Alpha meant that even if the pilot had reported the runway in sight he might still have mistaken taxiway Alpha for the runway. Also, the proximity of the runway and taxiway made it unlikely that the aerodrome controller could differentiate, using radar or visual means, between an aircraft approaching the taxiway or the runway.
During the second approach, the pilot had no external cues to question his mis-identification of the runway on the initial approach, and thus positioned the aircraft for a landing on taxiway Alpha. Although he was advised that he was following an aircraft for the same runway, it is apparent that this advice was not sufficient for him to review the situation. It is likely that his focus did not extend beyond flying the final approach and preparing for the landing.
The occurrence highlights the need for adequate pre-flight preparation and for pilots to utilise available resources. Had the pilot had more time, it is likely that he would have been better prepared for the approach and landing to an unfamiliar aerodrome. Additional time may also have provided an opportunity for the pilot to consider other resources that were available. In this respect, he may have considered advising the controllers that it was his first time into Sydney, or immediately notified them of the perceived runway infringement. Either action would probably have provided additional information to assist in his subsequent decision making while operating in what was essentially (for the pilot) a foreign environment.
Local safety action
Airservices Australia addressed a number of procedural issues identified during their investigation of the occurrence.
|Date:||31 May 2001||Investigation status:||Completed|
|Time:||1632 hours EST|
|State:||New South Wales||Occurrence type:||Depart/app/land wrong runway|
|Release date:||21 January 2002||Occurrence category:||Incident|
|Report status:||Final||Highest injury level:||None|
|Aircraft manufacturer||Cessna Aircraft Company|
|Type of operation||Charter|
|Damage to aircraft||Nil|
|Departure point||Dubbo, NSW|
|Role||Class of licence||Hours on type||Hours total|