Indonesian investigators comb Mandala 737 wreckage in residential area near airport for signs of power loss

Indonesia’s National Transport­ation Safety Committee (NTSC) is examining whether the Boeing 737-200 that crashed just after take-off in Medan last week suffered a power loss, but is also trying to determine whether its flaps were deployed correctly.

Domestic carrier Mandala Airlines was operating the 24-year-old 737-200 (PK-RIM), which crashed on 5 September less than 1min after take-off from the airport at Medan, the main city on Sumatra island. Eyewitness reports say the aircraft climbed to a maximum of 100ft (30m) before it hit an approach light at the end of a runway and crashed about 500m from the airport boundary in a residential district, killing nearly 50 people on the ground.

NTSC chairman Setyo Rahardjo says 99 of the 117 people on board the Jakarta-bound flight, including the two pilots and three cabin crew, were also killed. The 18 survivors are being treated in hospital. Setyo says investigators have found that “a fan blade was... not in good condition”, but have yet to determine whether this was the case before the crash. The two Pratt & Whitney JT8D-15 engines were not operating at the same RPM, says Setyo, who adds: “There was lower power.”

The investigators are also focusing on the aircraft’s flap setting. Setyo says they have yet to determine whether the flaps were deployed correctly. They have found that “three screwjack actuators came loose from a flap and wing”, but it is not yet clear whether this was the result of crash damage or was a problem before takeoff. The US National Transportation Safety Board is assisting the NTSC investigation.

The aircraft’s flight data recorder and cockpit voice recorder have been recovered and sent to the USA for analysis, says Setyo. The NTSB has sent a three-member team “with expertise in aircraft structures and aircraft engines” to Indonesia to assist. Indonesian state-owned aircraft manufacturer Indonesian Aerospace is also helping by storing aircraft wreckage awaiting analysis at its facility in Bandung on Java island.

Mandala Airlines is a commercial passenger airline that has been operating since 1969.

LEITHEN FRANCIS/SINGAPORE

Source: Flight International