It was shortly after midnight in New Zealand when Virgin Australia flight 134 approached the runway at Christchurch airport.
Hours earlier, as the Boeing 737 prepared to leave Sydney with 111 passengers on board, there was no significant weather forecast for their arrival, except for a bit of rain in Christchurch.
When plane’s wheels touched the tarmac on runway 29 — the airport’s shorter and rarely used runway — the mighty aircraft did not slow down. And it continued towards the edge of the runway.
As water sprayed around the sliding Boeing 737 and the smell of burning rubber filled the air, it finally came a stop just five metres from the runway’s edge, a new report has revealed.
The report, released this week, followed a three-year investigation by the Australian Transport Safety Bureau (ATSB) into the landing on May 11, 2015.
According to the report, about 30 minutes before landing, flight 134 from Sydney got the clearance to land at runway 29 instead of runway 02, due to rain at Christchurch. It touched down at 12.14am.
But after the first officer, who was landing the aircraft, applied the full reverse thrust and speedbrakes, something didn’t feel right.
The first officer “did not receive the expected sensation of being restrained against the seat belt and shoulder harness, and the aircraft did not decelerate as expected,” according to the ATSB report.
Crew told the ATSB it felt like the aircraft was sliding or skidding. A flight attendant said while she heard the brakes “squealing”, the 737 did not slow down.
“She could also smell burning rubber and was unable to see outside as there was a large amount of water spray,” the report said.
Meanwhile, the captain noted there was “a lot more” surface water on that section of the runway than at the start of it.
“The first officer reported that he was focused on the red runway end lights,” the report said.
“The captain reported that when reverse thrust was stowed near the runway end, there was enough surface water on the runway to create a wall of spray.”
The pilots applied hard manual braking and the aircraft came “slowly sliding” to a stop just five metres from the edge of the runway.
The aircraft then taxied to the terminal. No injuries or damage was reported – but he ATSB found a number of factors contributed to the aircraft coming dangerously close to a runway excursion.
One issue was just months before the incident Virgin Australia had changed the definition of a “damp runway” from one that should be treated as wet, to instead be treated as dry.
The report also noted the increased workload of the pilots due to the changing weather and change in runway.
Air traffic control had warned the crew “there were ‘quite a few changes from the previous (plan), you want to have a listen'”, but they didn’t get the opportunity as they rushed to prepare a new landing approach, investigators were told.
“The crew’s high workload coincided with the time when critical information was conveyed by air traffic control regarding the changing reported runway surface conditions at Christchurch from dry to wet,” the report said.
“The crew inadvertently missed this information and based on a pilot broadcast of the perceived runway conditions, they believed the conditions were reported as damp.”
If there had been cross-checking of information reports indicating it was raining at Christchurch airport and the runway was wet, the crew would have known they couldn’t land safely on runway 29 at that time, the report found.
“This would have likely resulted in the crew seeking an alternative landing solution such as changing runways (if available), holding to burn off fuel or diverting to another airport,” it said.
The report found the water on the runway resulted in reduced braking capability and the aircraft experienced “viscous aquaplaning”.
But it said the actions of the captain and first officer in handling the landing ultimately prevented the aircraft from coming off the runway.
The International Civil Aviation Authority has committed to a new method for assessing and reporting on runway surface conditions. the changes will be introduced by 2020.
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