The complaints are about the safety mechanism cited in preliminary reports for an October plane crash in Indonesia that killed 189. 

The disclosures found by The News reference problems during flights of Boeing 737 Max 8s with an autopilot system during takeoff and nose-down situations while trying to gain altitude. While records show these flights occurred during October and November, information regarding which airlines the pilots were flying for at the time is redacted from the database. –Dallas Morning News

One captain who flies the Max 8 said in November that it was “unconscionable” that Boeing and federal authorities have allowed pilots to fly the plane without adequate training – including a failure to fully disclose how its systems were distinctly different from other planes.