The pilots of a doomed Lion Air Boeing 737 Max scoured a handbook as they struggled to understand why the jet was lurching downward, but ran out of time before it hit the water, three people with knowledge of the cockpit voice recorder contents said.
The investigation into the crash, which killed all 189 people on board in October, has taken on new relevance after the U.S. Federal Aviation Administration and other regulators grounded the model last week following a second deadly accident in Ethiopia.
Investigators examining the Indonesian crash are considering how a computer ordered the plane to dive in response to data from a faulty sensor and whether the pilots had enough training to respond appropriately to the emergency, among other factors.