Lion Air failed to properly rectify a fault with the auto speed brake on one of its Boeing 737-400s before it was involved in a runway overrun accident at Pontianak on 2 November 2010.

The aircraft, registered PK-LIQ, was operating a service to Pontianak from Jakarta Soekarno-Hatta International airport, and were aware of difficulties in selecting thrust reversers and speed brake deployment on the aircraft. This had been previously reported 13 times, Indonesia's National Transportation Safety Committee says in its final report on the accident.

As the crew made their approach to Pontianak, the flight data recorder (FDR) shows that the aircraft made an unstable approach, and the crew should have initiated a go-around.

Instead, the approach continued, and the aircraft touched down long of the intended touchdown point.

“After the aircraft touched down, the pilot reported that the thrust reverser was hard to operate and the speed brake did not auto-deploy,” the NTSC says.

After sensing no deceleration, the crew manually deployed the speed brake 42 seconds after touchdown, and were also able to deploy thrust reversers. That was not sufficient to prevent a runway overrun, and the 737 eventually came to rest 70m from the end of the runway.

All six crew and 169 passengers were evacuated using the emergency slides, and no injuries were reported.

The NTSC found that there was “inconsistency” between the actions taken by the carrier and the aircraft’s maintenance manuals for the rectifications previously performed on the thrust reversers and auto speed brakes.

It also noted that the crew were unable to “accurately perceive what was going on in the flight deck and outside the airplane” during the unstable approach, and called on Lion Air to enforce crew discipline to encourage go-arounds during an unstable approach.

The NTSC says that Lion did not provide any information on changes made following the accident.

Source: Cirium Dashboard