Chronology Of Seconds Before Sriwijaya Air SJ-182 Fall From Black Box Analysis Results

JAKARTA - The National Transportation Safety Committee (KNKT) released a preliminary report on the condition of the Sriwijaya Air SJ-182 aircraft from the analysis of the black box flight data recorder (FDR) data.

Chairman of the NTSC Aviation Accident Investigation Subcommittee, Nurcahyo Utomo, explained that Sriwijaya Air SJ-182 initially departed Jakarta Soekarno-Hatta International Airport for Supadio Pontianak Airport at 14:36 WIB, Saturday, January 9, 2021.

After take off, this aircraft follows the departure path that has been determined following the ABASA 2D departure path. FDR noted that at an altitude of 1,980 feet, the autopilot began to activate.

"Then, the plane continues to rise. At an altitude of approximately 8,150 feet, the left engine power control lever (throttle) moves backward and the engine power or engine speed also decreases. Meanwhile, the right side engine is fixed," said Nurcahyo in a virtual press conference. , Wednesday, February 10.

Furthermore, at 14:38 WIB, 51 seconds, the Sriwijaya Air SJ-182 pilot asked the air traffic control (ATC) to turn towards 75 degrees due to weather conditions. ATC allows.

Due to a change in direction, ATC estimates that Sriwijaya Air SJ-182 will meet another aircraft departing from Soekarno-Hatta on the south runway.

Although Sriwijaya Air SJ-182 departed from the northern runway, these two planes had the same destination, namely Pontianak.

"Because it was expected to pass, SJ-182 was asked to stop climbing at an altitude of 11,000 feet," he said.

At 14:39 WIB, 47 seconds, the plane passed an altitude of 10,600 feet, the plane was in the direction of 46 degrees and began to look to turn left. The left engine power control lever moves backwards again, while the right one is still.

ATC instructed SJ-182 pilots to ascend to 13,000 feet. The pilot answered at 14:39 WIB, 59 seconds. "This is the last communication recorded on the pilot's communication recording with ATC at Soekarno Hatta Airport," said Nurcahyo.

At 14:40 WIB, 05 seconds, FDR recorded the highest altitude of the aircraft at 10,900 feet. After this altitude, the plane began to descend. The autopilot is suddenly inactive. The plane's direction at that time was 16 degrees.

At that time, the nose of the Sriwijaya Air SJ-182 aircraft was in an up or pitch up position and the plane began to tilt to the left. The left engine power regulating lever is reduced again, while the right one remains.

At 14:40 WIB, 10 seconds, FDR recorded the system so that the pilot set the speed and thrust of the aircraft automatically (autothrottle) was not active. Then, the stance of the plane lowered. 20 seconds later, FDR stops recording.

For information, FDR Sriwijaya Air SJ-182 was found on January 12, 2021 by the joint SAR team. At that time, the FDR was immediately taken to the NTSC to download the data. The successfully downloaded data includes 370 parameters, during the operation of approximately 27 hours. In it, includes 18 flights, including flights that have crashed.