Software may have re-engaged without human intervention before crash, say sourcesBoeing anti-stall software on a doomed Ethiopian Airlines jet re-engaged as many as four times after the crew initially turned it off due to suspect data from an airflow sensor, two people familiar with the matter said. Boeing’s anti-stall software, known as MCAS, is at the centre of investigations into both the Ethiopian Airlines crash last month and a Lion Air accident in Indonesia in October that together killed nearly 350 people. Doing so does not shut down the MCAS system completely but severs an electrical link between the software and aircraft systems, a person familiar with the technology said. Boeing is in the midst of upgrading the software while adding extra training. After the pilots turned off MCAS, the plane over the next few minutes gained roughly 2,000 feet, but dived into the ground after the renewed succession of nose-down inputs from MCAS.

Source: Ethiopian News April 03, 2019 11:03 UTC