AAIB Bulletin: 4/2016

Runway 25 at Warton, descending on final approach. Blackpool ATC contacted D-ISJP and asked for confirmation that the crew were still in visual contact with Warton. The commander responded that they were over Warton. A clearance to land on Runway 28 at Blackpool was issued and acknowledged. The co-pilot, having realised that they were lined up with the wrong runway, carried out a go-around, during which the commander initiated a turn to the left. The co-pilot resumed control and, in response to a query from Blackpool ATC, advised that visual contact with Blackpool had been lost. Blackpool ATC instructed the aircraft to turn right on to a track of 280° and to climb to 2,000 ft. The crew then completed a visual approach and landed on Runway 28 at Blackpool. Recorded data Radar information was available from three radar heads. The radar at St Annes, which is located less than 1 nm to the south-east of Blackpool Airport, provided a complete record of the approach and landing (Figure 1). Ground based recordings of RTF communications between ATC and the aircraft, and telephone conversations between controllers at Blackpool and Warton airfields, were also available. Flight crew information The commander had recorded a total of 12,000 flying hours, of which 5,500 were on type. The co-pilot had a total of 250 flying hours, of which 50 hours were on type. This flight was a line training sector, with the commander responsible for making the radio transmissions. Both pilots provided reports to the investigation. Airport information Runways The main runway at Blackpool Airport is Runway 28/10. It is 1,869 m in length, 46 m wide and is equipped with approach lighting. The main runway at Warton is Runway 25/07. It is 2,422 m in length, 46 m wide and is also equipped with approach lighting. There have been several instances of misidentification of the two airfields by inbound aircraft. Air Traffic Control Warton Aerodrome Traffic Zone (ATZ) is a circle of 2.5 nm radius, centred on the main runway, with an upper limit of 2,000 ft. It is notified as permanently active. Permission to enter the ATZ must be obtained from Warton ATC, when available, or from Blackpool ATC. Otherwise, traffic must remain clear. Additionally, there is a Military Aerodrome Traffic Zone (MATZ) of non-standard dimensions at Warton. Warton air traffic services operate on weekdays only: at the time of the incident radar services were operational. MATZ crossing for traffic inbound to Blackpool is co-ordinated by Blackpool ATC. Blackpool ATC operates a procedural service and radar is not available. At the time of the incident, the Blackpool combined approach/tower radio frequency was busy, with several traffic movements in the vicinity of the airport. 54 ©Crown copyright 2016 AAIB Bulletin: 4/2016 D-ISJP EW/G2015/03/13 Analysis The co-pilot was under training and there was also a large experience gradient between the two pilots. The co-pilot identified there was a potential for misidentification of the two airfields in his approach briefing but, even so, the aircraft made an approach to the wrong airfield. At a late stage, the co-pilot recognised the error and initiated a go-around. Warton ATC were notified of the aircraft by Blackpool ATC when it was co-ordinated through the western section of the MATZ. The confusion started to arise on the first radio contact between the aircraft and Blackpool ATC. The aircraft was cleared to the BPL but the commander did not read back the clearance. The controller repeated the clearance but again it was not read back. Blackpool ATC then requested the range of the aircraft from the BPL but the response was read back with reference to POL, a VOR located 33 nm to the east of Blackpool Airport. The incorrect readback was not corrected and, unknown to the controller, the aircraft turned east, directly towards POL. This suggested that the crew believed they had been cleared towards POL. The commander reported the field in sight and was asked to continue towards the BPL. His readback did not include the instruction to continue towards the BPL, an omission that was not challenged. Thus, a second opportunity to resolve the misunderstanding was missed and the aircraft continued tracking in the direction of the POL. Two minutes later, Warton ATC, who had radar contact with the aircraft, became concerned about its position and contacted Blackpool ATC. Warton ATC offered to provide a radar service for the aircraft but Blackpool ATC did not use this option. Thus, a further opportunity to resolve the situation was missed. When the commander confirmed he was visual with both airfields, Blackpool ATC issued a clearance for a visual approach. The controller again cautioned the crew about the position of Warton, to the south-east of Blackpool. The commander then disconnected the autopilot, took control and flew the aircraft manually. The aircraft turned to the left and initially tracked towards Blackpool but then turned further left towards Warton. Blackpool ATC contacted the aircraft, asking for its range and advised the crew of traffic at Blackpool, on a touch-and-go. At the same time, an aircraft was backtracking Runway 25 at Warton, which may have confirmed to the crew that they were looking at the correct runway. Warton telephoned Blackpool once more, to inform them that D-ISJP had misidentified the airfield. The co-pilot, meanwhile, realised that the aircraft was at the wrong airfield and carried out a go-around. He also, temporarily, took over the radio transmissions and responded to an enquiry from Blackpool ATC. The aircraft was then re-directed towards Blackpool and the situation was resolved. Conclusions The recorded radio transmissions from this incident demonstrate how a lack of standard radio telephony discipline can contribute to developing a misunderstanding. It arose first, 55 ©Crown copyright 2016 AAIB Bulletin: 4/2016 D-ISJP EW/G2015/03/13 perhaps, because there is some similarity between the sound of “bravo papa lima” and “papa oscar lima”, but, once begun, it was exacerbated by incomplete readbacks and the reduced situational awareness of the crew. Both ATC units were aware that the aircraft was going in the wrong direction but accepted the commander’s assurances.