Boeing unveils fix to flight system after deadly crashes

Boeing employees work on a 737 MAX jet at the company's factory in Renton, Washington—the aviation giant has unveiled a fix to t
Boeing employees work on a 737 MAX jet at the company's factory in Renton, Washington—the aviation giant has unveiled a fix to the software system of the jet, which has suffered two deadly crashes in recent months

Embattled aviation giant Boeing pledged Wednesday to do all it can to prevent crashes like the two that killed nearly 350 people in recent months, as it unveiled a fix to the flight software of its grounded 737 MAX aircraft.

Boeing gathered hundreds of pilots and reporters to unveil the changes to the MCAS stall prevention system, which has been implicated in the tragedies in Ethiopia and Indonesia, as part of a charm offensive to restore the company's reputation.

"We are going to do everything to make sure that accidents like this don't happen again," Mike Sinnett, Boeing's vice president of product strategy, told reporters at a factory in Washington state.

Meanwhile, across the country in the nation's capital, the head of the US air safety agency faced harsh questions from senators over its relationship with and oversight of Boeing.

Dan Elwell, the acting head of the Federal Aviation Administration, defended his agency but acknowledged that as systems become more complex, the FAA's "oversight approach needs to evolve."

Transportation Secretary Elaine Chao and other top officials were also on the hot seat on Capitol Hill.

Boeing chief Dennis Muilenburg was not called to the Senate hearing, but is expected to testify at a later date.

Boeing's vice president of product strategy, Mike Sinnett, presented the flight software fix for the company's embattled 737 MAX
Boeing's vice president of product strategy, Mike Sinnett, presented the flight software fix for the company's embattled 737 MAX passenger jet

Ahead of the tough questioning, the company launched a campaign to convince the flying public that it is addressing the issues with the 737 MAX, including a fix to the Maneuvering Characteristics Augmentation System (MCAS) implicated in the deadly crashes.

At the company's massive factory in Renton, Washington, Boeing unveiled the software changes and offered reassurances.

Sinnett said it will take only about an hour to install the updates and they can begin as soon as regulators authorize the changes, which were developed "after months of testing and hundreds of hours."

Authorization pending

The MCAS, which makes the aircraft dive in order to regain speed if it detects a stall or loss of airspeed, was developed specifically for the 737 MAX, which has a heavier engine than its predecessor, the 737 NG.

Timeline of the history of the Boeing 737 MAX aircraft since its certification by the US Federal Aviation Administration in 2017
Timeline of the history of the Boeing 737 MAX aircraft since its certification by the US Federal Aviation Administration in 2017

Among the changes, the MCAS will no longer repeatedly make corrections when the pilot tries to regain control, and will be automatically disconnected in the event of disagreements between the two "angle of attack" (AOA) sensors, the company said.

This is a major change because until the Ethiopian Airlines tragedy earlier this month, the MCAS was set to react to information from a single sensor and would repeatedly override pilot corrections.

The initial investigation into the Lion Air crash in Indonesia in October found that one of the AOA sensors failed but continued to transmit erroneous information to the MCAS.

Boeing also will install a warning feature—at no cost —- called a "disagree light" to indicate to the pilot when the left and right AOA sensors are out of sync.

The company also is revising pilot training, including for those already certified on the 737, to provide "enhanced understanding of the 737 MAX" flight system and crew procedures.

Southwest is one of the airlines that flies the now grounded 737 MAX aircraft
Southwest is one of the airlines that flies the now grounded 737 MAX aircraft

US pilots complained after the Lion Air crash that they had not been fully briefed on the system.

'Directly involved'

In Washington, US aviation regulators faced questions about how certification for the MAX was handled.

Lawmakers also want to know why officials did not immediately ground the aircraft after an Ethiopian Airlines 737 MAX 8 crashed shortly after takeoff near Addis Ababa on March 10, killing all 157 people onboard.

The delay has given rise to suspicions of a too-cozy relationship between regulators and the American plane maker, especially since Chinese and European authorities moved quickly to ban the planes as soon as similarities with the Lion Air crash were raised.

Workers stand under the wing of a Boeing 737 MAX airplane at the company's factory in Renton, Washington
Workers stand under the wing of a Boeing 737 MAX airplane at the company's factory in Renton, Washington

The FAA—which delegates some certification procedures to Boeing, including for parts of the MAX—was "directly involved" in the safety review of the MCAS, Elwell said.

"The certification process was detailed and thorough," but "time yields more data," he added.

A Boeing official meanwhile said there was no need to revamp a regulatory process that has "continued to lead to safer and safer airplanes."

At a separate hearing, Chao said she was "concerned about any allegations of coziness with any company," but noted that allowing Boeing to handle some of its own safety certifications was necessary because the FAA "can't do it on their own."

She said she has ordered the Transportation Department's inspector general, Calvin Scovel, to investigate the MAX certification, and Scovel in turn noted various concerns with FAA inspectors and procedures.

Boeing 737 MAX deliveries and orders, per region and company
Boeing 737 MAX deliveries and orders, per region and company

In his prepared testimony, he called on the agency to tighten oversight of companies that self-certify.

But a Boeing official countered that wholesale changes were not needed, saying: "In general, the process has worked and continues to work, and we see no reason to overhaul the process."


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US regulators under fire, Boeing launches charm offensive

© 2019 AFP

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Mar 27, 2019
When will US Congress unveil a solution to regulatory capture?

Mar 27, 2019
"The initial investigation into the Lion Air crash in Indonesia in October found that one of the AOA sensors failed but continued to transmit erroneous information to the MCAS.

Boeing also will install a warning feature—at no cost —- called a "disagree light" to indicate to the pilot when the left and right AOA sensors are out of sync."

Not that media reports are correct but I read that there was only one AOA sensor on the planes that crashed.

Also if the 2 sensors "disagree" one would think that more than turning on a warning light is needed.

Mar 27, 2019
I also read that the 2nd sensor was an extra cost option.

Mar 27, 2019
When will US Congress unveil a solution to regulatory capture?
Not to mention, when will the FAA get properly funded to do the oversight everyone assumes they're doing when they're not?

Maybe instead of border walls and bombs, we could fund the FAA.

Mar 28, 2019
Our lack of proper border enforcement results in more deaths than that crash. MS13 is rampant in our cities and our jails are filled with illegal immagrants.

Mar 28, 2019
OOOOps.......immigrants

Mar 28, 2019
There are a lot of systems on a plane that could be used to verify the AoA readings. Air speed and altimeter come to mind right off the top of my head. For instance the air speed increased dramatically which would have be impossible if the AoA was near the stalling danger point.

Mar 28, 2019
I have to say that preventing the flight crew from flying the jet as a default option looks like a classic case of software engineers writing stuff that doesn't admit the reality that humans are more reliable than computers. Boeing screwed this one up.

When the plane is pointing at the ground, the pilots are going to pull up. If the computer doesn't let them, crunch. Better to belly-flop from a stall than go in nose first.

Worse yet, every good landing is accomplished by stalling the aircraft just as you approach the ground. What if the computer decides that's a stall and points the nose down? This is duuuhhh ummm and obvious evidence the software engineers had never piloted an aircraft.

Mar 28, 2019
Also they must have accelerometers , as in your $500 cell phone, on the aircraft that could have proven the AoA sensor to be wrong. This is all free stuff that just a few lines of code could have used to sense an error.

Mar 28, 2019
You don't need accelerometers. You just need pilots who can look out the windows and go, "Gee, I think the plane's gonna crash. I better pull up." Stopping them-- or even making it complicated-- is a classic Bad Idea. Whoever designed that shit needs to not have a job any more.

Increasingly, software engineering despises subject matter expertise. This is the most destructive-- though by far not the only-- example of the fuckups this attitude can engender. You get the SMEs and then you listen to them. If you don't be prepared for catastrophes. And don't pretend "It wasn't me!!!! Honest!!!!"

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