On 11 June 2014, an ATR 72-600 (PK-WGK) being operated by Wings Air on a scheduled domestic passenger flight from Lombok to Surabaya as IW1861 was unable to avoid hitting FOD on the centreline of the landing runway at Surabaya in normal day visibility and sustained significant lower fuselage damage. There were no injuries to the occupants but eight substantial puncture holes were subsequently found in the lower aircraft fuselage, all attributed to running over a 4.5kg chisel. Two other items of FOD, a coil of compressor hose and a pneumatic drill (jackhammer) were subsequently recovered from the same part of the runway.
An Investigation was carried out by the Indonesian National Transportation Safety Committee (NTSC) - the Komite Nasional Keselamatan Transportasi (KNKT). CVR and FDR data from the damaged aircraft were both downloaded but it was subsequently concluded that the latter would not be relevant. ATC TWR recordings were also obtained.
It was noted that the 25 year-old Captain had 3,506 flying hours experience on type and that the 26 year-old First Officer had 2,221 flying hours experience on type. The total flying experience was not recorded for either pilot. The First Officer was PF for the flight involved but the Captain had taken control as the aircraft decelerated after touchdown and before the FOD was hit in accordance with the standard procedure to address the lack of a steering tiller at the right hand pilot position. No information was given about the TWR controller involved.
It was established that the runway at Surabaya had been notified as closed between 0100 and 0500 LT in order for repairs to be made to the surface by a team of 8 external contractor personnel led by two airport operator employees from the Airport Facility Readiness Team. Their tasks required the use of four vehicles and a range of equipment which included, but was not limited to, one or more pneumatic compressors, pneumatic drills, chisels, high air pressure hoses, asphalt mixers, small containers for asphalt mixture and debris sweepers.
At 0405 LT, ARFF personnel began their routine vehicle serviceability check which included driving one of the vehicles along the runway during which, although their personnel had not been trained in runway inspection, included conducting such an inspection. At about the same time, personnel from the Airport Facility Readiness Team, who were trained in runway inspection which was one of their designated responsibilities, also carried out such an inspection. Subsequent to both of these inspections, the runway maintenance team reported to the TWR controller that the runway repair work had finished and that “the runway maintenance team had left the runway”. However, no runway inspection was then performed by anyone nor requested by the TWR controller and 10 minutes later, whilst it was still dark, the 3000 metre-long 45 metre-wide runway was opened to traffic using the 10 direction.
At 0510 LT, an Airbus A320 landed and following this, 11 aircraft departed up to 0606 LT. None of these aircraft reported seeing any objects on the runway. At 0520 LT, nine minutes before official daylight began, a sweeper vehicle requested permission to “cross the runway” at an unrecorded position and its driver also did not report any objects on the runway. Then, at 0609 LT, a Boeing 737-900ER landed and its crew made the first report of several objects which looked like cable and drilling equipment seen at the intersection of the runway with taxiway N5 (see the runway diagram below). This report was acknowledged by the TWR controller who, after advising other pilots to “pay attention when passing exit taxiway N5” nevertheless then cleared two more aircraft to depart (neither reported sighting any debris) before attempting unsuccessfully to contact the Airport Facility Readiness section by radio to advise of the pilot report. When he got no reply, he contacted the ARFF and asked them to “check for the existence of the reported object” and they despatched a vehicle accordingly.
When this vehicle requested clearance to enter the runway to carry out the requested inspection, the TWR controller instructed them to hold position until three more aircraft had landed. Thereafter, another Boeing 737-900ER landed and reported to TWR that there were objects on the centreline of the runway just before the taxiway N5 intersection which “consisted of drilling equipment with long cable”. Almost immediately, TWR cleared an Airbus A320 to depart and there was no subsequent report from its flight crew of any object on the runway.
The runway in use showing the location of the reported FOD just before the N5 RET. [Reproduced from the Official Report]
Next in the landing sequence was an ATR 72-600 which was cleared to land and exit the runway via taxiway N5, the intersection where the two previous landing aircraft had reported seeing equipment. During the aircraft’s landing roll, 13 seconds after the Captain had taken over control as the groundspeed reduced, its flight crew heard impact noises as they hit something on the runway centreline in the vicinity of the N5 intersection. They subsequently informed the TWR controller that they had seen “drilling equipment and cable near the runway centreline” but were able to continue taxiing in. Two minutes later, a CRJ 1000 landed and the crew reported to TWR that there were some “big pieces of metal on the runway centreline near taxiway N5”. One minute after this, a Boeing 737-800NG landed after which the TWR controller finally decided to close the runway to allow the ARFF inspection to proceed. Once on the runway, they found a compressor hose approximately 10 metres in length, a pneumatic drill and a 4.5kg chisel on the runway located as indicated below. Damage to the aircraft lower fuselage was not discovered until it had arrived at its parking stand on the apron where eight holes ranging in size from 26cm x 14cm to 53cm x 34cm were discovered.
The Investigation conducted a comprehensive examination to establish the extent of airport and ATC procedures which would be expected to eliminate the risk of equipment being left on a runway then opened for traffic and those which would minimise the risk to aircraft safety in the event that such items were reported by runway users. It was found that the Aerodrome Manual lacked any record of its status or updating and did not contain any procedures covering the procurement of external contractors for airside work or any requirement for hazard identification and risk management prior to such runway maintenance activity. There were also no documented procedures for runway inspection following runway maintenance or other construction work on the movement area.
The location of the three objects found (left) and close ups of them (right). [Reproduced from the Official Report]
Other deficiencies identified in respect of the airport operation by the responsible body, the Surabaya (Juanda) Branch Office of PT Angkasa Pura 1 included:
- a mismatch between the actual airport opening hours and those which were promulgated
- the reliance on runway inspections conducted by RFFS personnel, none of whom had received training for that task which was designated as the responsibility of the Airport Operation and Readiness section
- the failure of the Airport Operation and Readiness section to ensure they were contactable when on duty.
It was concluded that the actions of the TWR controller once they began to receive reports of objects on the runway were inappropriate and noted that they had failed to follow the intent of the applicable AC170-02. This included the handling of an obstructed runway which required that “appropriate action”, defined as cancelling further takeoff clearances and instructing any aircraft on final approach to go around, must be taken in the event that a controller “becomes aware of [...] the existence of any obstruction on or in close proximity to the runway likely to impair the safety of an aircraft taking off or landing”. It was noted that the absence of any reports of objects on the runway by departing aircraft was likely to be attributable to their becoming airborne prior to the N5 intersection.
The Investigation formally identified two Contributory Factors in respect of the occurrence as follows:
- The runway inspection that was performed while the runway maintenance had not been finished resulted in objects which were of a dark colour and left on a dark surface not being found before the runway was opened.
- Insufficient information regarding the objects and their location might have led to improper assessment of the consequences for runway operation and delayed removal of the objects.
Six Safety Recommendations were made as a result of the Investigation as follows:
- that PT. Angkasa Pura 1 Branch Office Juanda International Airport develop a procedure for hazard identification and risk assessment if assigning a company that does not have experience of performing airside tasks. [04.B-2018-14.1]
- that the PT. Angkasa Pura 1 Branch Office Juanda International Airport develop a procedure for inspection following runway maintenance or construction work on movement area. [04.B-2018-14.2]
- that the PT. Angkasa Pura 1 Branch Office Juanda International Airport ensure that personnel of each department involved in the operation of the airport shall be available when it is in operation. [04.B-2018-14.3]
- that the PT. Angkasa Pura 1 Branch Office Juanda International Airport include the identification number and revision status of their Aerodrome Manual. [04.B-2018-14.4]
- that the PT. Angkasa Pura 1 Branch Office Juanda International Airport update their Operations Manual in accordance with the current operational status. [04.B-2018-14.5]
- that the Airnav Indonesia Branch Office Juanda develop a procedure for action to be taken by a controller after receiving information about the existence of any obstruction likely to impair the safety of aircraft operations. [04.A-2018-14.6]
The Final Report of the Investigation was released on 17 October 2018.