Tag Archives: Boeing 737 MAX

U.S. ends Boeing 737 MAX flight ban after crash probes

By David Shepardson and Eric M. Johnson

WASHINGTON/SEATTLE (Reuters) – After nearly two years of scrutiny, corporate upheaval and a standoff with global regulators, Boeing Co won approval on Wednesday from the U.S. Federal Aviation Administration to fly its 737 MAX jet again after two fatal disasters.

The FAA detailed software upgrades and training changes Boeing must make in order for it to resume commercial flights after a 20-month grounding, the longest in commercial aviation history.

The 737 MAX crashes in Indonesia and Ethiopia killed 346 people within five months in 2018 and 2019 and triggered a hailstorm of investigations, frayed U.S. leadership in global aviation and cost Boeing some $20 billion.

The U.S. plane maker’s best-selling jet will resume commercial service facing strong headwinds from a resurgent coronavirus pandemic, new European trade tariffs and mistrust of one of the most scrutinized brands in aviation.

Families of the Ethiopian crash victims said in a statement on Wednesday that they felt “sheer disappointment and renewed grief” following the FAA’s decision to return the aircraft to service.

“Our family was broken,” Naoise Ryan, whose 39-year-old husband died aboard Ethiopian Airlines flight 302, said on Tuesday.

The 737 MAX is a re-engined upgrade of a jet first introduced in the 1960s. Single-aisle jets like the MAX and rival Airbus A320neo are workhorses that dominate global fleets and provide a major source of industry profit.

Of the U.S. airlines with 737 MAX jets, American Airlines plans to relaunch the first commercial MAX flight since the grounding on Dec. 29, followed by United Airlines in the first quarter of 2021 and Southwest Airlines in the second quarter next year.

Leading regulators in Europe, Brazil and China must issue their own approvals for their airlines after independent reviews, illustrating how the 737 MAX crashes upended a once U.S.-dominated airline safety system in which nations large and small for decades moved in lock-step with the FAA.

When it does fly, Boeing will be running a 24-hour war room to monitor all MAX flights for issues that could impact the jet’s return, from stuck landing gear to health emergencies, three people familiar with the matter said.

Shares jumped in premarket trading and were on track for their highest level since June.

LONG RUNWAY AHEAD

FAA Administrator Steve Dickson signed an order lifting the flight ban early on Wednesday and the agency released an airworthiness directive detailing the required changes.

“We’ve done everything humanly possible to make sure” these types of crashes do not happen again, Dickson told Reuters, saying he felt “100% confident” in the plane’s safety.

The FAA is requiring new pilot training and software upgrades to deal with a stall-prevention system called MCAS, which in both crashes repeatedly and powerfully shoved down the jet’s nose as pilots struggled to regain control.

The FAA, which has faced accusations of being too close to Boeing in the past, said it would no longer allow Boeing to sign off on the airworthiness of some 450 737 MAXs built and parked during the flight ban. It plans in-person inspections that could take a year or more to complete, prolonging the jets’ delivery.

Boeing is scrambling to keep up maintenance and find new buyers for many of its mothballed 737 MAXs after receiving cancellations from their original buyers. Demand is further sapped by the coronavirus crisis.

Even with all the hurdles, resuming deliveries of the 737 MAX will open up a crucial pipeline of cash for Boeing and hundreds of parts suppliers whose finances were strained by production cuts linked to the jet’s safety ban.

Numerous reports have faulted Boeing and the FAA on the plane’s development. A U.S. House of Representatives report in September said Boeing failed in its design and development of the MAX, and the FAA failed in its oversight and certification.

It also criticized Boeing for withholding crucial information from the FAA, its customers, and pilots including “concealing the very existence of MCAS from 737 MAX pilots.”

The chief executive of Boeing urged staff to speak up whenever they see behavior going against values of safety, quality and integrity. “We have implemented a series of meaningful changes to strengthen the safety practices and culture of our company,” Dave Calhoun told employees in a letter.

The House on Tuesday unanimously passed a bill to reform how the FAA certifies airplanes, while a Senate panel is to consider a similar bill on Wednesday.

Boeing faces lawsuits from crash victim families.

(Reporting by Eric M. Johnson in Seattle, Tracy Rucinski in Chicago, David Shepardson in Washington, Allison Lampert in Montreal and Jamie Freed in Sydney; Editing by Matthew Lewis and Nick Zieminski)

House to vote on FAA reform bill after Boeing 737 MAX crashes

By David Shepardson

WASHINGTON (Reuters) – The U.S. House of Representatives is set to vote on Tuesday on bipartisan legislation to reform the Federal Aviation Administration’s (FAA) aircraft certification process after two fatal Boeing 737 MAX crashes killed 346 people.

The 737 MAX has been grounded since March 2019 but the FAA is set on Wednesday to approve the plane’s return to service after a lengthy review, new software safeguards and training upgrades.

The House bill requires an expert panel to evaluate Boeing’s safety culture and recommend improvements, and mandates that aircraft manufacturers adopt safety management systems and complete system safety assessments for significant design changes. It also requires that risk calculations be based on realistic assumptions of pilot response time, and that risk assessments are shared with regulators.

The House Transportation and Infrastructure Committee approved the measure unanimously on Sept. 30.

Representative Peter DeFazio, the panel’s chairman, told Reuters in a statement that the measure is “a strong bill that has support from both sides of the aisle and addresses something we all agree on — keeping people safe. There’s no reason to wait until the next Congress to get this done.”

DeFazio, a Democrat, said the FAA failed to properly ensure the safety of the 737 MAX, and called aircraft certification “a broken system that broke the public’s trust.”

Boeing and the FAA declined to comment on the legislation.

A report released by DeFazio found the 737 MAX crashes were the “horrific culmination” of failures by Boeing and the FAA and called for urgent reforms.

The House bill would extend airline whistleblower protections to U.S. manufacturing employees, require FAA approval of new workers who are performing delegated certification tasks, and impose civil penalties on those who interfere with the performance of FAA-authorized duties.

The panel’s top Republican, Representative Sam Graves, said the bill “will help ensure the United States remains the gold standard in aviation safety and maintain our competitiveness in the aerospace sector because we were able to leave partisan politics at the door (and) adhere to the experts’ conclusions that our system should be improved but not dismantled.”

It is unclear if the U.S. Senate will take up the measure before the current Congress expires this year.

(Reporting by David Shepardson; Editing by Sonya Hepinstall)

House panel approves FAA reform bill after Boeing 737 MAX crashes

By David Shepardson

WASHINGTON (Reuters) – A U.S. House of Representatives committee on Wednesday unanimously approved bipartisan legislation to reform the Federal Aviation Administration’s aircraft certification process after two fatal Boeing 737 MAX crashes that killed 346 people.

Representative Peter DeFazio, who chairs the Committee on Transportation and Infrastructure, said the House would vote on the sweeping reform measure later this year.

The Boeing Co 737 MAX has been grounded since March 2019. Among other reforms, the bill requires that an expert panel evaluate Boeing’s safety culture and recommend improvements.

“Those crashes were the inevitable culmination of stunning acts and omissions within Boeing and the (FAA),” DeFazio said at a hearing.

He said the FAA had failed to properly ensure the safety of the 737 MAX, and called aircraft certification “a broken system that broke the public’s trust.”

Boeing and the FAA have declined to comment on the legislation.

The bill would require American aircraft manufacturers to adopt safety management systems and complete system safety assessments for significant design changes, ensure that risk calculations are based on realistic assumptions of pilot response time, and share risk assessments with the FAA.

A report released last week by House Transportation committee Democrats found that the 737 MAX crashes were the “horrific culmination” of failures by Boeing and the FAA and called for urgent reforms.

The House bill would extend airline whistleblower protections to U.S. manufacturing employees, require FAA approval of new workers who are performing delegated certification tasks for the agency, and impose civil penalties on those who interfere with the performance of FAA-authorized duties.

FAA Administrator Steve Dickson is conducting an evaluation flight at the controls of a 737 MAX in Seattle, a key milestone as the U.S. plane maker works to win approval for the aircraft to resume flights.

(Reporting by David Shepardson; editing by Jonathan Oatis)

Boeing 737 MAX crash victims urge more steps by FAA before flight approval

By Tracy Rucinski and Eric M. Johnson

CHICAGO/SEATTLE (Reuters) – The U.S. Federal Aviation Administration’s proposed changes to the Boeing Co. 737 MAX fail to fix structural flaws on the jet that suffered two fatal crashes, victims’ families said on Thursday, urging additional steps including a full aerodynamic review.

The FAA said last month it is proposing requiring four key 737 MAX design and operating changes that would pave the path for the jet to fly again, possibly later this year, following an 18-month global grounding.

But in a filing as part of a 45-day public comment period on the agency’s proposed airworthiness directive, crash victim families said the proposals leave critical questions on the airplane’s safety unanswered.

“They fail to address the root cause of the problem: the 737 MAX’s inherent aerodynamic instability,” said the families, who were advised by aerospace experts.

Boeing’s proposed modification of a software system called MCAS linked to both crashes does not address the underlying aerodynamic problem, introduces greater complexity, and may create additional failure modes, they said in the filing, which was signed by more than 2,000 family members.

The families called for a complete aerodynamic evaluation of the 737 MAX to understand the airplane’s pitch-up tendency and a simplified crew alert system so that pilots are not overwhelmed by multiple warning systems.

In both crashes, the MCAS flight control system, triggered by erroneous data from a single angle-of-attack airflow sensor, repeatedly and forcefully pushed down the jet’s nose as pilots struggled to regain control.

If the MAX is certified to fly again with a less powerful MCAS system, the families called for a third active angle-of-attack sensor and accompanying software to detect sensor failures.

They also said the FAA should disclose to the public the data it used to make its decisions and commission a new independent review board to assess the findings and the 737 MAX’s safety before returning it to service.

An 18-month investigation by U.S. lawmakers found the crashes were the “horrific culmination” of a series of faulty technical assumptions by Boeing engineers, a lack of transparency on the part of Boeing’s management, and grossly insufficient oversight by the FAA.

Aside from the FAA’s final airworthiness directive, Boeing is facing reviews by foreign regulators, who are also weighing new pilot training procedures.

(Reporting by Tracy Rucinski; Editing by Chizu Nomiyama and Andrea Ricci)

United Continental pulls 737 MAX flights out of schedule

FILE PHOTO: A worker from United attends to some customers during their check in process at Newark International airport in New Jersey , November 15, 2012. REUTERS/Eduardo Munoz/File Photo

(Reuters) – United Continental Holdings Inc said on Monday it had pulled Boeing Co’s 737 MAX flights out of its schedule through early July, following similar moves by rivals American Airlines Group Inc and Southwest Airlines Co.

United, with 14 MAX jets, had largely avoided cancellations by servicing MAX routes with larger 777 or 787 aircraft.

But the airline’s president, Scott Kirby, warned last week that the strategy was costing it money and could not go on forever.

Boeing’s 737 MAX planes have been grounded worldwide since March after an Ethiopian Airlines jet crashed, killing all 157 aboard, just five months after a similar crash of Indonesia’s Lion Air flight.

(Reporting by Ankit Ajmera in Bengaluru; Editing by Anil D’Silva)

Southwest removes 737 MAX jets from schedule through August 5

FILE PHOTO: A number of grounded Southwest Airlines Boeing 737 MAX 8 aircraft are shown parked at Victorville Airport in Victorville, California, U.S., March 26, 2019. REUTERS/Mike Blake

CHICAGO (Reuters) – Southwest Airlines Co said on Thursday it would remove its 34 Boeing Co 737 MAX jets from its flying schedule through Aug. 5, leading to around 160 daily flight cancellations during the revised summer schedule.

In a statement, Southwest President Tom Nealon said the decision is meant to “increase the reliability of our schedule and reduce the amount of last-minute flight changes,” especially during the summer travel season.

(Reporting by Tracy Rucinski; Editing by Leslie Adler)

Ethiopian crash report shows pilots wrestling with controls

Ethiopian transport minister Dagmawit Moges addresses a news conference on the preliminary report to the Ethiopian Airlines ET 302 plane crash in Addis Ababa, Ethiopia April 4, 2019. REUTERS/Tiksa Negeri

By Jason Neely

ADDIS ABABA (Reuters) – Pilots of an Ethiopian Airlines jet wrestled with controls to stay aloft but plunged to the ground after restoring current to a computer system that was ordering the nose down because of faulty sensor data, a preliminary report showed on Thursday.

The Boeing 737 MAX hit an airspeed as high as 500 knots (575 miles per hour), well above its operational limits, before cockpit data recordings stopped as the plane crashed on March 10 killing all 157 passengers and crew.

“Most of the wreckage was found buried in the ground,” said the report by Ethiopia’s Aircraft Accident Investigation Bureau.

The doomed flight crashed six minutes after take-off from Addis Ababa in clear conditions.

Boeing’s top-selling aircraft has been grounded worldwide since the March 10 disaster, which came just five months after a Lion Air 737 MAX crash in Indonesia that killed 189. An initial report into that accident also raised questions about the jet’s software, as well as training and maintenance.

Ethiopia urged Boeing to review its flight control technology and said pilots of the state carrier had carried out proper procedures in the first public findings on the crash.

“The crew performed all the procedures repeatedly provided by the manufacturer but was not able to control the aircraft,” Transport Minister Dagmawit Moges told a news conference, presenting the outlines of a preliminary report.

Boeing Co, whose shares rose 2.4 percent on Thursday but were still below their level before the crash, said its software fix for its anti-stall system would give pilots the authority to always override the system if activated by faulty sensor data.

Families of the victims, regulators and travelers around the world have been waiting for signs of whether the two crashes are linked, and the extent to which Boeing technology and the actions of the Ethiopian Airlines pilots played a role.

Ethiopian investigators did not blame anyone for the crash, stressing the importance of international rules requiring civil probes to focus on recommendations for safer flight. A final report is due within a year.

FILE PHOTO: People walk past a part of the wreckage at the scene of the Ethiopian Airlines Flight ET 302 plane crash, near the town of Bishoftu, southeast of Addis Ababa, Ethiopia March 10, 2019. REUTERS/Tiksa Negeri/File Photo

FILE PHOTO: People walk past a part of the wreckage at the scene of the Ethiopian Airlines Flight ET 302 plane crash, near the town of Bishoftu, southeast of Addis Ababa, Ethiopia March 10, 2019. REUTERS/Tiksa Negeri/File Photo

CONTROL SYSTEM

But in a clear indication of where Ethiopian investigators are directing the attention of regulators, they cleared the pilots of using incorrect procedures and issued two safety recommendations focused on the recently introduced aircraft.

They suggested that Boeing review the controllability of the 737 MAX systems and that aviation authorities confirm any changes before allowing that model of plane back into the air.

“Since repetitive uncommanded aircraft nose down conditions are noticed … it is recommended that the aircraft control system shall be reviewed by the manufacturer,” Dagmawit said.

The nose-down commands were issued by Boeing’s so-called MCAS software. The preliminary report into the Lion Air disaster suggested pilots lost control after grappling with MCAS, a new automated anti-stall feature that repeatedly lowered the nose of the aircraft based on faulty data from a sensor.

The Federal Aviation Administration, which has come under fire over the way it decided to certify the plane and its MCAS software, cautioned the investigation had not yet concluded.

“We continue to work toward a full understanding of all aspects of this accident. As we learn more about the accident and findings become available, we will take appropriate action,” the U.S. agency said in a statement.

FAULTY DATA

Ethiopian Airlines said its crew had followed all the correct guidance to handle a difficult emergency.

However, the report could spark a debate with Boeing about how crew members responded to problems triggered by faulty data from an airflow sensor, particularly over whether they steadied the plane before turning key software off.

Questions on whether the pilots had leveled out the plane before disengaging MCAS and how many times MCAS activated were not answered in a news conference that lasted about 40 minutes.

The New York Times quoted Dagmawit as saying pilots turned MCAS off and on, which is not the step recommended in published Boeing procedures telling crew to leave it off once disabled, though there is growing debate among safety experts about what unstable conditions may have prompted such an unusual step.

Most accidents take months of analysis because of the need to trace backwards to find a root cause from tangled evidence.

“There is a big difference between having the data and knowing the cause,” a senior European investigator said.

Officials denied reports of tensions between Ethiopian officials and U.S. and other foreign investigators accredited to the probe.

“We don’t have any reservations from different stakeholders who were engaged in the investigations,” chief investigator Amdye Ayalew Fanta said.

Following a previous Ethiopian Airlines accident off Beirut in 2010, Addis Ababa authorities rejected the conclusions of a Lebanese investigation citing pilot error and suggested the aircraft had exploded in a possible act of sabotage.

Aviation safety analyst Paul Hayes said deeper investigation would delve into the role played by software and how pilots were able to respond, and said he hoped scars from the 2010 dispute would not get in the way of a comprehensive investigation.

“Pilots shouldn’t have to cope with such an emergency situation. We need to understand what are the factors that meant these two crews were overcome,” said Hayes, safety director at UK-based consultancy Flight Ascend.

“It is unusual for there to be a single cause,” he added.

Boeing said on Wednesday it had successfully tested an update of MCAS software designed to make it easier to handle.

(Reporting by Jason Neely; Writing by Katharine Houreld and Tim Hepher; Additional reporting by Maggie Fick, Jamie Freed and David Shepardson; Editing by Mark Potter)

American Airlines pilots will test 737 MAX software fix in Boeing simulator

FILE PHOTO: An aerial photo shows Boeing 737 MAX airplanes parked at the Boeing Factory in Renton, Washington, U.S. March 21, 2019. REUTERS/Lindsey Wasson

By Tracy Rucinski

CHICAGO (Reuters) – American Airlines pilots will test Boeing Co’s 737 MAX software fix on simulators this weekend, the pilots’ union told Reuters on Thursday, a key step in restoring confidence in the jet after two fatal crashes.

Boeing has been working on a software upgrade for an anti-stall system and pilot displays on its fastest-selling jetliner in the wake of the deadly Lion Air crash in Indonesia in October.

Similarities between the flight path in the Lion Air incident and a fatal Ethiopian Airlines crash on March 10 have raised fresh questions about the system. The two crashes killed a total of 346 people.

American is the second-largest U.S. operator of the MAX in the United States with 24 jets, behind Southwest Airlines with 34.

“This airplane can be a safe airplane, and there have been great strides on getting a fix in the works, but I’ll have a better feel after we can test it out,” said Mike Michaelis, safety committee chairman of the Allied Pilots Association (APA), which represents American Airlines pilots.

Michaelis said one APA pilot and one pilot from American’s management team would test the software fix in Renton, Washington, where Boeing builds the MAX and has two simulators.

“We have been engaging with all 737 MAX operators and we are continuing to schedule meetings to share information about our plans for supporting the 737 MAX fleet,” Boeing spokesman Paul Bergman said.

MAX jets were grounded worldwide in the wake of the Ethiopian crash.

Boeing has indicated it would deploy the software update by April or sooner, though it was unclear how long it would take to get the jets flying again. Pilots must complete FAA-approved computer-based training on the changes, followed by a mandatory test, and some pilots have said more may be needed.

After Lion Air, American pilots met with Boeing executives in Fort Worth, Texas and demanded to know why the manufacturer had not told them about the new system, known as MCAS.

They also questioned whether a 56-minute iPad course on the MAX had been sufficient.

MAX simulator training is not required, partly because few simulators exist. Southwest and American expect to receive MAX simulators later this year.

The main simulator producer, Canada’s CAE Inc, said it has delivered nine of the simulators, which are now in high demand but take about a year to build. CAE expects to deliver 20 more in 2019.

“When it comes to safety issues, it has to be a full-course meal, nothing a la carte,” said Dennis Tajer, a spokesman for the American Airlines pilots’ union and a 737 pilot.

(Reporting by Tracy Rucinski; additional reporting by Allison Lampert in Montreal and Eric M. Johnson in Seattle; editing by Darren Schuettler and Nick Zieminski)

With 737 MAX grounded, airlines face daily scheduling challenges

FILE PHOTO: Southwest Airlines Co. Boeing 737 MAX 8 aircraft sit next to the maintenance area after landing at Midway International Airport in Chicago, Illinois, U.S., March 13, 2019. REUTERS/Kamil Kraczynski

By Tracy Rucinski and Allison Lampert

CHICAGO/MONTREAL (Reuters) – Following the global grounding of Boeing Co’s 737 MAX jets, U.S. and Canadian airlines that fly the roughly 175-seat aircraft face a fresh logistical challenge every day: which flights to cancel and which to cover with other planes.

Southwest Airlines Co and American Airlines Group Inc, the two largest MAX operators in the United States, said they have bolstered their reservation and operations teams to figure out how to spread flight cancellations across their networks, not just on MAX flights.

American Airlines, for example, had most of its 24 MAX jets flying in and out of Miami, where load factors have been full during the Spring Break season.

“We can’t just cancel all of those flights, so the goal is to spread out the cancellations across our entire system to impact the least amount of customers,” American Airlines spokesman Ross Feinstein said.

This means that an American Airlines flight from Miami to the Caribbean initially scheduled on a 737 MAX may now fly on a 737-800 with a similar seat configuration, while that 737-800 flight is canceled.

“It’s a challenge to explain to customers who weren’t previously booked on a MAX why their flight is canceled,” Feinstein said.

The 737 MAX jets were grounded last week following two fatal crashes in the past five months, the causes of which are under investigation.

Southwest, the largest MAX operator in the world with 34 jets representing about 5 percent of its total fleet, is canceling about 150 flights per day due to the grounding, but not all on MAX routes.

Steve West, Senior Director of Southwest’s Operations Control, said the company is trying to cancel flights five days in advance, while looking at issues such as weather, that could free up jets, like last week’s snowstorm in Colorado.

Southwest and American were already grappling with a larger than the normal number of out-of-service aircraft, further straining their fleets.

So far United Airlines, with 14 MAX aircraft, has not canceled any flights due to the grounding but has had to put smaller aircraft on some routes and fly the larger 777 to places like Hawaii.

It is unclear how long the grounding will last. Deliveries are also on hold, meaning an additional hit to airlines due to receive more of the jets this year.

Boeing has over 5,000 orders for the MAX, which sold fast thanks to its higher fuel-efficiency and longer range. Now airlines face a dent to 2019 profits.

Calgary-based WestJet said it took steps prior to the MAX grounding to start protecting trans-border flights to sunny destinations that were previously scheduled to fly with the carrier’s 13 MAX planes.

Meanwhile, Air Canada said on Tuesday it would remove its 24 737 MAX aircraft from its schedule until at least July 1, 2019.

“It is easier to put the aircraft back in the schedule than to pull it out,” said a source familiar with the carrier’s thinking, who is not allowed to publicly discuss its strategy.

 

(Reporting by Tracy Rucinski; Editing by Nick Zieminski)

Exclusive: Cockpit voice recorder of doomed Lion Air jet depicts pilots’ frantic search for fix – sources

FILE PHOTO: An Indonesian National Transportation Safety Commission (KNKT) official examines a turbine engine from the Lion Air flight JT610 at Tanjung Priok port in Jakarta, Indonesia, November 4, 2018. REUTERS/Beawiharta/File Photo

By Cindy Silviana, Jamie Freed and Tim Hepher

JAKARTA/SINGAPORE/PARIS (Reuters) – The pilots of a doomed Lion Air Boeing 737 MAX scoured a handbook as they struggled to understand why the jet was lurching downwards, 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 as the U.S. Federal Aviation Administration (FAA) and other regulators grounded the model last week after 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.

It is the first time the voice recorder contents from the Lion Air flight have been made public. The three sources discussed them on condition of anonymity.

Reuters did not have access to the recording or transcript.

A Lion Air spokesman said all data and information had been given to investigators and declined to comment further.

The captain was at the controls of Lion Air flight JT610 when the nearly new jet took off from Jakarta, and the first officer was handling the radio, according to a preliminary report issued in November.

Just two minutes into the flight, the first officer reported a “flight control problem” to air traffic control and said the pilots intended to maintain an altitude of 5,000 feet, the November report said.

The first officer did not specify the problem, but one source said airspeed was mentioned on the cockpit voice recording, and a second source said an indicator showed a problem on the captain’s display but not the first officer’s.

The captain asked the first officer to check the quick reference handbook, which contains checklists for abnormal events, the first source said.

For the next nine minutes, the jet warned pilots it was in a stall and pushed the nose down in response, the report showed. A stall is when the airflow over a plane’s wings is too weak to generate lift and keep it flying.

The captain fought to climb, but the computer, still incorrectly sensing a stall, continued to push the nose down using the plane’s trim system. Normally, trim adjusts an aircraft’s control surfaces to ensure it flies straight and level.

“They didn’t seem to know the trim was moving down,” the third source said. “They thought only about airspeed and altitude. That was the only thing they talked about.”

Boeing Co declined to comment on Wednesday because the investigation was ongoing.

The manufacturer has said there is a documented procedure to handle the situation. A different crew on the same plane the evening before encountered the same problem but solved it after running through three checklists, according to the November report.

But they did not pass on all of the information about the problems they encountered to the next crew, the report said.

The pilots of JT610 remained calm for most of the flight, the three sources said. Near the end, the captain asked the first officer to fly while he checked the manual for a solution.

About one minute before the plane disappeared from radar, the captain asked air traffic control to clear other traffic below 3,000 feet and requested an altitude of “five thou”, or 5,000 feet, which was approved, the preliminary report said.

As the 31-year-old captain tried in vain to find the right procedure in the handbook, the 41-year-old first officer was unable to control the plane, two of the sources said.

The flight data recorder shows the final control column inputs from the first officer were weaker than the ones made earlier by the captain.

“It is like a test where there are 100 questions and when the time is up you have only answered 75,” the third source said. “So you panic. It is a time-out condition.”

The Indian-born captain was silent at the end, all three sources said, while the Indonesian first officer said “Allahu Akbar”, or “God is greatest”, a common Arabic phrase in the majority-Muslim country that can be used to express excitement, shock, praise or distress.

The plane then hit the water, killing all 189 people on board.

French air accident investigation agency BEA said on Tuesday the flight data recorder in the Ethiopian crash that killed 157 people showed “clear similarities” to the Lion Air disaster. Since the Lion Air crash, Boeing has been pursuing a software upgrade to change how much authority is given to the Maneuvering Characteristics Augmentation System, or MCAS, a new anti-stall system developed for the 737 MAX.

The cause of the Lion Air crash has not been determined, but the preliminary report mentioned the Boeing system, a faulty, recently replaced sensor and the airline’s maintenance and training.

On the same aircraft the evening before the crash, a captain at Lion Air’s full-service sister carrier, Batik Air, was riding along in the cockpit and solved the similar flight control problems, two of the sources said. His presence on that flight, first reported by Bloomberg, was not disclosed in the preliminary report.

The report also did not include data from the cockpit voice recorder, which was not recovered from the ocean floor until January.

Soerjanto Tjahjono, head of Indonesian investigation agency KNKT, said last week the report could be released in July or August as authorities attempted to speed up the inquiry in the wake of the Ethiopian crash.

On Wednesday, he declined to comment on the cockpit voice recorder contents, saying they had not been made public.

(Reporting by Cindy Silviana in Jakarta, Jamie Freed in Singapore and Tim Hepher in Paris; writing by Jamie Freed; Editing by Gerry Doyle)