Sriwijaya Air Boeing 737-500 Crash, January 9th 2021.

Flight SJ182 departed Jakarta, with 62 people on board, after a delay due to heavy rain, there was thunderstorm activity in the area.

The departure route was initially normal but then the aircraft turned onto a north easterly heading rather than the planned northwest; this could have been due to weather avoidance but it would be normal practice to agree a deviation with the controller via radio.

The aircraft seems to have climbed to Flight Level 110 (aprox 11,000 feet) before spiralling or plummeting down at a very high rate of descent, losing the height gained in well under 60 secconds, finally hitting the sea with fatal results. The wreckage has been located and the flight data and cockpit voice recorders should be easily recoverable.

Possible causes:

As always so soon after a tragedy like this there is a desire for answers and there are none that can be relied upon at this point. Other crashes that have similar profiles have been caused by the following example factors

  • Loss of control due to crew disorientation; usually when in cloud.
  • Major structural failure of some kind. This would need a cause, such as corrosion in the airframe, extreme turbulence in a thunderstorm cell for example, or an explosive device.
  • A mid air collision with another aircraft; none have been reported in the area.
  • A control system or instrument system failure that the crew could not manage.

Indonesia had a rapid expansion in aviation around the millennium and the accident record was not good. There were issues with regulatory oversight, pilot training standards as well as maintenance; this eventually resulted in the EU banning all Indonesian aircraft from EU airspace. This ban was rescinded around 2018 when standards were perceived to have improved.

This airline had some aircraft grounded due to maintenance issues a year or two ago and the authorities notified them that they would cancel their operating certificate unless urgent action was taken. An agreement was reached with Garuda to meet the regulator’s requirements and operations continued.

Due to the Covid pandemic aviation has been badly disrupted and it has been a challenge to keep crews up to current requirements. I know some UK and other major airline crews have been refresher training in the simulator and being rostered to fly when possible to keep them within the required recency periods; I have no information on these issues for this airline. Once the accident investigation begins in earnest, we will hope to get some information on the amount of flying and training the pilots received prior to the crash.

This aircraft is not a Boeing MAX which was involved in the tragedies of the Lion Air and Ethiopian crashes and whilst a little elderly now the B737 series has been a reliable safe aircraft.