On 10 November 2009, an ATR 72-200 being operated by Kingfisher Airlines on a scheduled passenger flight from Bhavnagar to Mumbai India made a non precision approach to runway 27 at destination in day Visual Meteorological Conditions (VMC) and, after touching down late, left the runway at speed during landing. It ended up substantially damaged but there was no fire and none of the 42 occupants were injured.
The aircraft in the final resting position - reproduced from the Official Report
An Investigation was carried out by the Indian DGCA. Flight Data Recorder (FDR) and Cockpit Voice Recorder (CVR) data was available as were ATC radar and R/T recordings and also video recordings of all landings on runway 27 as mandated by the DGCA because of the reduced landing distance available (LDA).
It was noted that on the day of accident, maintenance action had meant that the secondary runway 14/32 had been closed and the primary runway 09/27 had been available only with a reduced LDA of 1703 metres beginning at a displaced landing threshold. The Meteorological Terminal Air Report (METAR) valid at the time of landing gave a W/V of 070° / 07 knots in slight rain and normal ground visibility so that a significant tailwind component had existed for the landing. It was also established that the previous landing aircraft, an Air India Airbus A319, had reported aquaplaning and the destruction of two runway edge lights to ATC which had sent runway inspection vehicle to inspect the runway. It was further established that the ATCO on duty was not familiar with the terminology of ‘aquaplaning’ and cleared the ATR72 to land without advising of water patches on the runway or advising of the aquaplaning reported by the previous A319.
The aircraft commander had been PF for the accident approach. Available evidence showed the aircraft had made the ATC-cleared LLZ-only approach very significantly above the specified vertical profile (see diagram below) and that both the crew and ATC had been aware of this at the time. FDR and ATC radar data showed that the aircraft had been in excess of 750 feet above the procedure vertical profile at a range of 4nm from touchdown and this had continued through 3nm, 2nm and 1nm range. At 1nm range, the actual height aal was 1400ft compared with the procedure profile height of 640 feet.
The vertical profile flown versus the one required by LLZ procedure - reproduced from the Official Report
According to the Investigation, at about 4 nm from touchdown, ATC had advised the aircraft to check altitude since it was high and “report field in sight”. Once this had been acknowledged to the effect that the field was in sight, a landing clearance was issued. Thereafter, it was found that the EGFWS Mode 1 ‘Sink Rate’ Warning had been “continuous till touch down” during which time the PF flew the aircraft manually. The Investigation noted that “the maximum rate of descent reached was 2550 fpm” and that “even below 500 ft (aal) the rate of descent was high and a maximum value of 2040 fpm was reached at a radio altitude of 291 feet”.
Touchdown occurred 700m beyond the displaced threshold and although the aircraft was correctly configured touchdown registered a 1.32g vertical acceleration. It was calculated during the Investigation that the remaining length of paved surface should have been just sufficient to stop the aircraft in the reported prevailing conditions without the onset of aquaplaning. However, the FDR data showed that the aircraft had aquaplaned when maximum braking had been applied with full reverse pitch. Directional control had been lost and as the aircraft moved to the left of the runway center line and the end of the runway approached with poor deceleration, the PF initiated a 45° turn to the right to avoid an overrun. The aircraft crossed a taxiway and continued onto an unpaved wet surface and over drainage pipes before stopping near a large open drain 150 metes away from the edge of the runway and 90 metres longitudinally from the paved surface of the landing runway. The evacuation was uneventful apart from the fact that it the crew were unable to shut down the No 2 engine even by pulling the fire handle, although by the time the latter method was attempted, there was no battery power.
It was concluded that the approach made had comprehensively failed to meet both the Operators stabilised approach criteria and their requirements for response to EGPWS Warnings. The approach brief given was found to have been inadequate and Crew Resource Management within the flight deck ineffective. The First Officer had not intervened to encourage - or make - a go around. In this context, the flight crew combination of a male expatriate PF and a female local PM was recorded but not discussed.
It was reported that a day prior to the reduced length availability of runway 27, the Chief Flight Inspector of DGCA Flight Standards Directorate had advised all scheduled service operators by telephone, and then followed up by written communication, some conditions which had to be met to support the maintenance of safe flight operations on the restricted-length runway. As per these instructions “only training captains are to be utilised for flight and the Co-pilot should have minimum 300 hours of experience on type. Further no assisted take off and landing is permitted and no operation shall take place when runway surface is wet”. It was established that the flight crew on the accident flight did not meeting the requirements since the aircraft commander was not a Training Captain. Also, the runway surface had (at the very least) been ‘wet’, a further contravention of the temporary restrictions which it was found that neither ATC nor the flight crew had been aware of.
It was determined that the Probable Cause of the event was: “the unstabilised approach and decision of (the) crew not to carry out a ‘go-around’”.
It was also concluded that Contributory Factors were:
- Water patches on the runway
- Inability of the ATCO to communicate (with) the (accident) aircraft about (the) aquaplaning of the previous aircraft
- Lack of input from the co-pilot.
Four Safety Recommendations were made as a result of the Investigation:
- Corrective training may be imparted to the involved crew in view of the lapses brought out on their part in the report.
- AAI (the ANSP) may bring it to the notice of all concerned that while giving the landing clearance to the aircraft the characteristics of aquaplaning or water patches on the runway, if any, should be mentioned.
- Kingfisher should evolve a system of disseminating the information affecting the safety of aircraft operation to all concerned immediately.
- Non shutting-off (of) the engine even after pulling down the fire handle may be referred to Aircraft Manufacturer for analysis.
The Final Report: Report on Accident to M/S Kingfisher Airlines ATR-72 Aircraft VT-KAC at Mumbay on 10.11.2009 of the Investigation was published on 25 November 2010