In the weeks after a Boeing jetliner crashed in the Java Sea near Indonesia last year, killing all 189 people on board, the manufacturer defended the plane’s safety features and publicly resisted calls to make changes to its system and pilot training procedures.

This month, following a second deadly crash of a 737 Max, a worldwide grounding of the planes by regulators, a stock slide and the loss of a multibillion-dollar contract, Boeing is taking a new approach. The company invited hundreds of pilots and airline partners to its Renton, Wash., assembly facility Wednesday in a hastily arranged meeting to explain new safety enhancements.

Boeing’s shift in tone — CEO Dennis Muilenburg said in a statement this week the company has been “humbled” — reflects growing pressure on the company’s bottom line as its fleet of jetliners sits idle at airports. It also comes as airlines that have placed orders for hundreds of additional 737 Max jets begin to question those investments. Last week, Indonesia’s national airline, Garuda, said it canceled its order for 49 jets because of “consumers’ low confidence” in the airplanes following the crashes.

[Indonesia’s Garuda airlines moves to cancel order for 49 Boeing 737 Max jets]

The Chicago-based manufacturer is working to fulfill orders for more than 4,000 737 Max jets from dozens of airlines, according to analysts at Cowen Washington Research Group.

Boeing is responding to rising public concerns about its Max planes in an effort to save the company’s image and prevent the loss of more business, said Shem Malmquist, an active Boeing 777 captain and a visiting professor at the Florida Institute of Technology.

“They took a different tack — a tack they should have taken in the first place,” Malmquist said.

The company’s changing response may be partly a function of how unusual the situation is, said Seth Seifman, an analyst at JPMorgan.

“The way that it took off in the press and on social media is not something that Boeing is used to,” he said. “It probably took some time to put together a public strategy to deal with that.”

Boeing has continued to defend the safety of its planes and deflect claims that its automation software may have contributed to either of the two crashes.

At the Renton event, officials from the aerospace giant defended the embattled 737 Max as the culmination of 50 years of aircraft development in which they said safety has been the first priority.

They also pushed back on the idea that something is inherently wrong with the aircraft development process within Boeing. Company officials also defended the process used to determine that the plane met government requirements. The process used to certify the plane is the subject of congressional inquiries, a Department of Transportation audit and a criminal probe by the Department of Justice.

The plane maker has to walk a fine line in its public statements. Admitting that any fault lies in Boeing’s planes, including software, would create legal liability for the company and damage its reputation for safety, said Scott Hamilton, managing director at Leeham Company, an aviation consultant. “Their public statements are completely driven by what their lawyers will allow them to say,” Hamilton said.

At the same time, Boeing is being pushed by regulators and customers to address the issues that may have led to two catastrophic crashes. While a preliminary report following last year’s Lion Air crash pointed to the role of the sensors, there has been no final conclusion on the cause of either crash.

After that incident, Boeing initially said it did not need to make changes to the automation system suspected of playing a role in the crash. If the system malfunctions, Boeing has always given pilots an easy way to override the automation system, executives said in interviews with the media.

“The appropriate flight crew response to [a system malfunction], regardless of cause, is contained in existing procedures,” a spokesman said in an email last November. The company “reinforced” those procedures in a bulletin to pilots that month, but said it wasn’t changing the procedure. It also emphasized that such action would be premature because the cause of the crash was unknown.

The company submitted a proposed software fix to the Federal Aviation Administration on Jan. 21, the agency has said.

A Boeing spokeswoman said the company “has been following the standard practice after any accident, supporting the investigating authorities, examining our aircraft design and operation, and taking action to enhance safety.”

[Pilots say they were in the dark about Boeing’s 737 Max safety update]

Safety concerns over the 737 Max intensified on March 10, when a Boeing Max 8 operated by Ethiopian Airlines crashed minutes after takeoff, killing 157. The FAA concluded, based on satellite data and evidence from the wreckage, that the Ethiopian incident and the earlier crash near Indonesia had enough in common that global fleets of the Max 8 should be grounded.

On Wednesday, Mike Sinnett, Boeing vice president of engineering and chief project engineer, detailed a set of new flight control features in which an alert will appear at the bottom of the pilot display screen when two of the plane’s external sensors capture different measurements, something that could indicate faulty data.

The briefing, before a phalanx of television cameras, occurred before the company met with more than 200 pilots, technical leaders, airline representatives and regulators ― all of whom have a stake in the 737 Max, which has been forbidden to fly passengers in the United States, Europe, China and elsewhere for almost two weeks.

Boeing was working to drum up support for a flight control system overhaul and a new pilot training regimen that it hopes will allay safety concerns raised by pilot groups and others. It plans to submit the final software fixes to the FAA for review this week, something that could hasten the process of lifting the grounding order.

American Airlines, United Airlines and Southwest Airlines — the three U.S. carriers flying 737 Max 8 or 9 jets at the time they were grounded — all said they sent representatives to the meeting.

Michael Quiello, vice president of corporate safety at United, said the airline is “optimistic” that the updates addressed the safety concerns about the 737 Max’s automation system. But, he said, “the U.S. commercial aviation system is the safest in the world because its foundation is built on rigorous data analysis and evidence-based independent oversight, and we look to the FAA to employ these tools as it reviews and certifies this software update.”

[How the FAA allows jetmakers to self certify that planes meet U.S. safety requirements]

Boeing is also rolling out new training for 737 Max pilots, consisting of a brief computer-based training course that walks pilots through features of the automation software, as well as additions to pilot manuals and a supplemental pilot bulletin. Though the new training is not yet finalized, two pilots familiar with Boeing’s discussions, who were not authorized to speak publicly, said the new computer-based course would only take 15 minutes. Notably, it is up to airlines to decide whether pilots should train on flight simulators specific to the 737 Max.

While Boeing hosted its meetings, lawmakers in Washington staged a Senate hearing on aviation safety and oversight on Wednesday afternoon. Among those offering testimony were Daniel K. Elwell, acting administrator of the Federal Aviation Administration; Robert Sumwalt, chairman of the National Transportation Safety Board; and Calvin L. Scovel III, the Transportation Department’s inspector general.

Boeing will also have to convince a skeptical community of global aviation professionals that the 737 Max will be safe to fly once the flight systems are updated.

Analysts say the financial toll on Boeing and its airline customers could grow as the crisis goes on. Boeing has suspended all future deliveries of the 737 Max 8 and 9 for as long as the grounding order is in place.

“Boeing will probably owe something to the airlines,” JPM’s Seifman said. If the grounding lasts two to three months, it’s possible Boeing could face roughly $1 billion to settle legal claims by the airlines, he said.

Those with future orders are waiting on a resolution. WestJet, which has two Max deliveries expected later this year, said it sent pilots to the Renton meeting Wednesday.

“As the duration of the Max grounding is still unknown, if our next delivery is before the grounding is lifted, we will not take the aircraft,” WestJet spokeswoman Morgan Bell said Tuesday. “However, if the grounding has been lifted and the aircraft is approved for re-entry into service by all relevant regulatory bodies, we will take all deliveries as intended.”

Boeing and the FAA have been working on the software and training fixes for months, but it is unclear why both organizations waited until after a second crash to publicly commit to them.

A Boeing official speaking on the condition of anonymity to discuss internal deliberations said the company has used lab and flight simulators to test how the new software would work in different scenarios, all of it in close coordination with FAA officials. Boeing flight-tested the software on a Boeing jet on Feb. 7 and again on March 12, the person said.

“Test pilots flew different maneuvers and flight conditions that exercised various aspects of the software update,” the Boeing official said.

The second test came two days after the Max 8 crash in Ethiopia.

Julia Duin in Seattle contributed to this report.