On the flight prior the LionAir accident flight on the Boeing Max registered as PK-LQP, an off-duty fully-qualified Boeing 737-MAX 8 pilot was traveling home on flight JT-43. The plane encountered problems similar to the next flight that crashed it (i.e. the LionAir accident flight from Denpasar to Jakarta.) The crew aboard the earlier flight managed to land the aircraft at the destination. Based on the crew’s entry in the AFML, the engineer at Jakarta flushed the left Pitot Air Data Module (ADM) and static ADM to rectify the reported IAS and ALT disagree and cleaned the electrical connector plug of the elevator feel computer. The aircraft was subsequently released to carry out flight JT610.(A different crew manned the fatal flight.) The pilot was interviewed by the Kantor Komite Nasional Keselamatan Transportasi–Ministry of Transportation of the Republic of Indonesia (KNKT). The KNKT committee is responsible for investigating and reporting air transportation system accidents, serious incidents and safety deficiencies involving air transportation system operations in Indonesia.
The KNKT estimates that the release of the final report for Lion B38M in August or September 2019.
The KNKT is cooperating with Ethiopian Authorities but will make no official comment. News media reports suggest that on the earlier LionAir flight, a third pilot had occupied the observer’s seat in the cockpit of flight JT-43 and that this pilot identified the automatic trim runaway issue at hand and initiated that the trim cut out switches be used.
The preliminary report on the LionAir crash is located HERE.