For example, the NTSB specifically cites the EAIB’s conclusion that aircraft electrical problems caused erroneous angle-of-attack (AOA) output. In its final report, the EAIB wrote electrical anomalies that existed since the time of the accident airplane’s production caused the AOA sensor heater to fail. As a result, the Ethiopian authority added, the AOA sensor provided erroneous values that caused the MCAS to repeatedly pitch the nose of the airplane downward until it struck the ground. The NTSB, however, found that impact with a foreign object, most likely a bird, resulted in the separation of the AOA sensor vane, causing erroneous readings. Although the EAIB appended Boeing’s multi-operator message to the final report, the EAIB failed to mention that the flaps information appeared in that document—thus rendering the finding misleading, concluded the NTSB.

Source: Ethiopian News January 24, 2023 18:24 UTC