Description

On 22 May 2020, an Airbus A320 (AP-BLD) being operated by Pakistan International Airlines on a scheduled domestic passenger flight from Lahore to Karachi as PK8303 touched down on runway 25L at destination in day VMC without its landing gear down and continued along the runway resting on its engines before taking off again. Both engines failed soon afterwards and when control was lost, it crashed into a residential district approximately 1340 metres from the runway 25L threshold and was destroyed. Only two passengers out of the 99 occupants survived and four people on the ground were injured, although one of those subsequently died.

Investigation

An Investigation is being carried out by the Pakistan Aircraft Accident Investigation Board (AAIB). Clearance of wreckage from the crash site prioritised successful recovery of the FDR and CVR which was achieved. The EGPWS Computer, the QAR and the Flight Controls Data Concentrator (FCDC) and ADIRU (Air Data Inertial Reference Unit) computers, which all contained NVM that was not crash protected were also recovered since they may yield useful data. All these units were taken to the BEA France in the custody of the AAIB Chief Investigator for examination and data retrieval. The FDR was undamaged and on download, its data was found to cover the whole flight until its electrical power supply ceased shortly before the crash. The CVR was externally damaged but it proved possible to remove its memory and obtain good data from it.

The prevailing weather conditions were noted as having been good throughout the flight which was uneventful until it reached the vicinity of its destination. Karachi Control cleared the flight for the Nawabshah 2A STAR and advised that it could expect an ILS approach to runway 25L. Later, clearance to the waypoint MAKLI, which is located 15 nm from the Karachi VOR on its 075 radial, followed with descent to FL050 approved and, following handover to Karachi APP, descent to 3000 feet.

As can be seen from the reconstructed vertical flight profile and accompanying airspeed graph below, the aircraft remained well above a normal descent profile and also maintained high speed. On reaching the MAKLI waypoint, it was still at 9780 feet and descending at around 245 KCAS. It was being flown manually with the speed brakes extended and ‘OPEN DES’ mode selected on the Flight Control Computer (FCU). The APP controller therefore requested what track miles would be “comfortable for descent” and in the absence of any response then advised making an orbit. However, no orbit was made and an attempt to intercept the ILS directly continued. FDR data indicated that the landing gear was selected down at 7,221 feet when about 10.5 nm from the runway and thereafter the rate of descent increased. The APP controller twice advised that the attempted direct approach should be discontinued but it was not.

FDR data showed that as the aircraft approached the ILS GS, flaps 1 had been selected at 243 KCAS and as it became fully established just inside 5nm and at approximately 1740 feet, the landing gear was raised and the speed brakes were retracted. Over-speed and EGPWS warnings were then triggered.

As it became clear that the crew intended to land the aircraft despite the highly unstabilised approach being flown and aware that there was no conflicting airborne traffic, the APP controller obtained a landing clearance by telephone from the TWR (runway) controller (who did not mention the absence of extended landing gear) and then issued it to the aircraft.

FDR data shows that passing 500 feet, the airspeed was recorded as 220 KCAS and the rate of descent as 2000 fpm with the landing gear still retracted and slats/flaps now at configuration 3. Various warnings and alerts related to over-speed, landing gear not down and ground proximity were all disregarded and touchdown followed with the landing gear retracted and the aircraft resting on its engines - see the CCTV still and runway marks below. Initially, braking action was attempted and reverse thrust was selected but after a brief action to select the landing gear lever to the ‘down’ position, it was returned to the ‘up’ position and a go-around was commenced. In the short time available, the observation by the TWR controller that the engines were in contact with the runway was not passed directly to the crew but to the APP controller but it was not then relayed to the crew.

The crew advised their intention to position for another ILS approach to runway 25L but about 4 minutes later, transmitted a ‘MAYDAY’ call from a downwind position advising that they could no longer maintain height after both engines had successively failed. By this time, the RAT had automatically deployed to power essential systems and since this did not, by design, include the FDR, its data recording had stopped shortly after the engines failed.

The aircraft was observed to adopt a high angle of attack before crashing at a low forward speed about 1340 metres from the runway 25L threshold just to the left of its extended centreline with the landing gear extended, slats at position 1 and flaps retracted. A post impact fire began at the point of impact and the remainder of the wreckage was spread over approximately 80 metres, essentially aligned along a single street - see below.

It was noted that the continuing Investigation will include examination of:

• aircrew and controller personnel records
• aircraft documents
• recovered aircraft wreckage
• aircraft maintenance records
• controller response to the situation and ANSP / regulatory oversight
• flight crew performance and training at the aircraft operator and regulatory oversight of same
• aircraft operator SMS, the Safety and Quality Management System of the CAA Directorate of Operations and the State Safety Programme
• pre-flight medical actions and initial post crash response by the CAA

A Preliminary Report of the Investigation on which this summary is based was published on 24 June 2020.

Related Articles

• Loss of Control
• Stabilised Approach
• Post Crash Fires
• Energy Management during Approach
• Landing Gear Problems: Guidance for Controllers