Indonesian Report on Lion Air Crash Finds Numerous Problems

JAKARTA, Indonesia — The first officer told the captain that he had been called at 4 a.m. and told to work the flight, which was not on his original schedule. The captain replied that he had the flu. He coughed 15 times in the hour before takeoff.

So began Lion Air Flight 610, which crashed into the Java Sea 13 minutes after taking off from Jakarta, Indonesia’s capital, a year ago, killing all 189 people aboard.

The pilots, one harried and one sick, could not know that they were in an untenable situation: They had been handed a plane that international investigators now say had a fatal design problem.

Their conversation was described in Indonesian investigators’ final report on the crash, which was released on Friday. It blamed a combination of factors for the disaster, including systematic design flaws in the Boeing 737 Max that were compounded by maintenance issues and lapses on the part of the flight crew.

Nurcahyo Utomo, an investigator for the Indonesian National Transportation Safety Committee, listed what he said were nine contributing factors, including an automated system’s reliance on a single sensor; the miscalibration of that sensor during repairs; a lack of flight and maintenance documentation; and a failure by the flight crew to manage the chaos in the cockpit as emergency warnings sounded.

“The nine factors have to happen together,” Mr. Nurcahyo said at a news conference in Jakarta. “If one of those nine contributing factors did not happen, the crash would not have happened.”

Less than five months after the Oct. 29 crash, another 737 Max went down in Ethiopia, killing 157 people. Malfunctions of the automated system, called MCAS, sent both the Lion Air plane and that Ethiopian Airlines plane, Flight 302, into nose dives from which they did not recover.

Boeing has been shaken by the crisis over the 737 Max, its best-selling jet, which has been grounded since March and is being investigated by regulators around the world. The company’s profits, which were released this week, fell by roughly half in the third quarter.

Boeing’s president and chief executive, Dennis Muilenburg, said in a written statement on Friday that the company was addressing the Indonesian regulators’ recommendations “and taking actions to enhance the safety of the 737 Max to prevent the flight control conditions that occurred in this accident from ever happening again.”

Last month, the National Transportation Safety Board in the United States found that Boeing had underestimated what sort of effect a malfunction of the MCAS system, which can automatically push the plane’s nose down, could have on the cockpit environment.

A multiagency report in the United States found that Boeing had not adequately explained to federal regulators how the system worked, and that the Federal Aviation Administration had relied on the company to check the technology.

The Indonesian report called for better F.A.A. oversight of how new aircraft are certified.

“We welcome the recommendations from this report and will carefully consider these and all other recommendations as we continue our review of the proposed changes to the Boeing 737 Max,” the F.A.A. said in a statement.

Latief Nurbana, whose 24-year-old son was killed in the Lion Air crash, said the report reinforced his belief that both Boeing and the F.A.A. bore responsibility.

“My response as a victim’s family member, as a father: As we have suspected since the beginning, this accident was caused by two institutions,” he said.

But the report found problems elsewhere, too.

The Lion Air plane had been in operation for just two months, and had four recorded problems in the weeks before the crash. On a flight the day before the crash, pilots had been able to fix a similar issue with the plane’s automated anti-stall system.

The crew of the doomed flight might not have been aware of that previous incident, the report said.

A so-called angle of attack sensor, which measures the plane’s angle of ascent, was probably miscalibrated by a company in Florida, the report found. It was off by 21 degrees from a second such sensor on the plane.

The report also found that the first officer of Lion Air Flight 610 had become confused about some procedures that were supposed to be performed from memory, and that the airline might not have properly addressed previous indications that the officer had not mastered those procedures.

Muktita Suhartono reported from Jakarta, and Austin Ramzy from Hong Kong.