Incident Overview
On 24 January 2007 at 1208 UTC, an Airbus A319-131 (registration G-DBCI) operated a commercial passenger flight from London Heathrow Airport to Leeds Bradford Airport. The aircraft, with two International Aero Engine V2522-A5 turbofan engines, was manufactured in 2006. On board were 5 crew and 53 passengers. No injuries were reported among crew or passengers. Damage was limited to all four main landing gear tyres.
Flight History
During the approach to Leeds Bradford, the aircraft broke cloud at approximately 3,000 ft in a snow shower. Air Traffic Control transmitted five advisory wind reports. At about 1,300 ft, the first officer, who was the Pilot Flying, requested full flap. Coincidentally, ATC transmitted a further wind check, which the commander acknowledged. A few seconds later, the first officer noticed the ECAM still indicated FLAP 3 and repeated the request. The commander then selected full flap, and the landing checklist was completed.
Immediately after touchdown, the flight crew noted that the brakes appeared to take effect immediately with greater than normal deceleration. The commander observed the AUTOBRAKE blue caption remained illuminated with no DECEL indication. The first officer 'dabbed' the brakes to disengage the autobrake, but without effect. The aircraft stopped on the runway, slightly left of the centreline. After stopping, the commander requested the first officer to apply the parking brake, but it was already set. Initially, only one tyre deflation was suspected, but all four main wheel tyres had deflated. Neither pilot reported abnormal noises during the landing. Passengers disembarked through normal exits and were taken by coach to the terminal.
Investigation
Cockpit Controls
The parking brake handle and flap selection lever are located on the aft section of the centre pedestal between the pilots' seats. The flap lever moves fore and aft through gates, while the parking brake is selected by grasping and rotating clockwise. Despite different shapes, both can be grasped similarly prior to selection. An inspection revealed that the identifying placard was missing from the parking brake selector.
Flight Warning Computer
The aircraft was fitted with a pre-'H2F3' standard Flight Warning Computer (FWC). In this standard, selecting the parking brake in-flight generates an amber PARK BRK caption in the lower right quadrant of the ECAM display but does not illuminate the master caution light or sound an aural alert. With the later 'H2F3' standard, the master caution light would illuminate and an aural tone would sound, along with a landing checklist item showing 'BRAKES PRK BRK ON - PARK BRK...OFF'.
Standard Operating Procedures
The operator's SOPs state: 'when the configuration of an aircraft is changed, positions of the surfaces should be monitored to confirm that the change has been accomplished.' The pre-landing check requires confirmation that no checklist items remain outstanding, but does not require checking the lower right quadrant for advisory messages.
Human Factors
The commander stated he had been involved in a previous landing at Leeds Bradford in difficult wind conditions resulting in significant runway use due to tailwind. He acknowledged no recollection of his action in response to the first officer's initial request for full flap. A psychologist's report commissioned by the operator noted that the commander may have been temporarily fixated on environmental conditions exacerbated by the perception that these could lead to repetition of a previous unpleasant event. This fixation, combined with simultaneous tasks, could have narrowed attention and led to a subconscious motor action transposed with the correct one.
Conclusions
In the later stages of the approach, the commander inadvertently set the parking brake instead of the flaps to FULL. He was probably focused on changing weather conditions due to a previous difficult landing at LBA and numerous wind advisory calls from ATC, the last coincident with the co-pilot's initial request for full flap. The FWC generated an advisory message on the ECAM but no additional 'attention getters'. Had the later standard been fitted, aural and visual cues would have been produced. The pre-landing checks required confirmation of no open checklist items but not advisory messages.
Safety Action
As a result of this event, the operator modified its SOPs to incorporate a pre-landing check of the lower right quadrant of the ECAM screen for advisory and caution messages.