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From the New York Times, March 19, 2019 regarding FAA available resources for oversight.




Federal Aviation Administration

Report Number: AV-2016-001Date Issued: October15, 2015

https://www.oig.dot.gov/sites/default/files/FAA Oversight of ODA Final Report^10-15-15.pdf

also, from a FOIA document using governmentattic.org, June 2012:

https://www.oig.dot.gov/sites/default/files/files/I10A000073SINV ROI.pdf

Edited by Don Hudson
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Credit: AW&ST, Sean Broderick, Thierrry Dubois

Boeing 737 MAX Groundings Break Protocol And New Ground
Mar 19, 2019
Sean Broderick and Thierry Dubois | Aviation Week & Space Technology

When Chinese regulators grounded the country’s Boeing 737 MAX fleet less than 24 hr. after the type’s second fatal accident in five months, many believed the move signaled an escalation in the simmering China-U.S. trade dispute. The move was indeed a signal, but not of heightened global trade tensions. Rather, it marked the likely pivot in aviation’s fleet-grounding analysis process from a data-driven, problem-identification approach to one that prioritizes speed and caution over certainty.

The Chinese order came early March 11 Beijing time—about 19 hr. after Ethiopian Airlines Flight 302 (ET302) went down 6 min. after departing Addis Ababa’s Bole International Airport, killing all 157 onboard. The Civil Aviation Administration of China (CAAC) gave domestic operators 9 hr. to park their MAX aircraft, which at nearly 100 is the largest concentration in any country. CAAC cited “the management principle of zero tolerance for safety hazards and strict control of safety risks” in making the move, adding that both 737-8 accidents “have certain similarities a word choice that would prove prescient.

Chinese officials did not know any more about what brought ET302 down than anyone else: The aircraft’s crew reported flight-control problems and requested clearance to return to Addis Ababa, and the flight ended soon after. Weather did not seem to be an issue.

The few known facts aligned with those of October 2018’s crash of Lion Air Flight 610 (JT610), another nearly new 737-8 that went down shortly after departure in clear weather after its pilots reported flight-control issues. Data from JT610’s flight data recorder (FDR) confirmed what the pilots suspected: They were battling a flight-control problem. Faulty angle-of-attack (AOA) sensor data activated an automated feature meant to help the MAX handle like its 737NG predecessor during steep turns or at slow speeds in manual flight, by trimming the horizontal stabilizer nose-down. The feature, the Maneuvering Characteristics Augmentation System (MCAS) flight-control law, is both a certification requirement and the JT610 probe’s focus.

A change to the MAX’s flight-control computers and the MCAS’ functionality was in the works well before the ET302 accident, and the Chinese—as did everyone else—knew this. Chinese media reports say CAAC officials consulted with Boeing and the FAA just after ET302. Their conclusion? The MCAS’s risks were not well-enough understood, by pilots or regulators, to allow the MAX to keep flying.

As the Chinese evaluated the situation, two operators, Ethiopian and Cayman Airways, made independent decisions to ground their MAXs. Neither was surprising: Ethiopian suffered the second accident, and Cayman had just introduced the type in November.

Cayman Airways was the first carrier to ground the MAX. Credit: joepriesaviation.net

Soon, however, the worldwide momentum for grounding grew. Late on March 11, Indonesia’s Directorate General of Civil Aviation said 737-8s operated by Lion Air and Garuda Indonesia would be grounded for inspections. South Africa’s Comair and Morocco’s Royal Air Maroc added their names to the growing list of those not waiting for more ET302 probe details.

On that same day, the FAA spoke out for the first time, issuing a Continued Airworthiness Notification to the International Community, reiterating that Boeing’s MCAS fix, based on lessons learned from the JT610 investigation, is in progress, and that the agency is on site assisting in the ET302 probe. “All data will be closely examined during this investigation, and the FAA will take appropriate action if the data indicates the need to do so,” the agency said.

More groundings followed March 12, with the Civil Aviation Authority of Singapore and Australia’s Civil Aviation Safety Authority banning the model’s operations. Australia acted “in the best interests of safety . . . in light of the two recent fatal accidents,” says CASA CEO Shane Carmody. “This is a temporary suspension while we wait for more information to review the safety risks of continued operations of the Boeing 737 MAX.”

Later in the day, Europe broke ranks—both with the U.S. and its European Aviation Safety Agency (EASA) regulator. The UK, France, Germany, and Ireland announced MAX operational bans. EASA soon followed.

The European regulator was arguably as close to the evolving situation around MCAS as any non-U.S. entity. The bilateral aviation safety agreement between the U.S. and European Union has forged strong ties between the FAA and EASA.

Data from Lion Air Flight 610’s (JT610) flight data recorder (top) and ground-based ADS-B data that traces Ethiopian Airlines Flight 302’s (ET302) path (bottom) have clear similarities, including vertical speed and altitude variations. The JT610 probe is focusing on inaccurate angle-of-attack data that triggered nose-down inputs meant to keep the MAX from stalling, but that instead confused the pilots and caused the aircraft to dive. The flight profile comparison suggests ET302 may have faced the same issue.

The Europeans were presented with Boeing’s proposed MCAS changes on Feb. 7, including an automatic AOA-disagree alert and software modifications to reduce the amount of nose-down input it can give. On March 7, just three days before ET302 crashed, Boeing applied for approval of proposed new training requirements tied to the changes.

But with pressure mounting as state regulators and some operators grounded the MAX, EASA late on March 12 issued its own edict. Executive Director Patrick Ky cited the automatic dependent surveillance-broadcast (ADS-B) data and reports of flight-control problems as key factors. EASA saw “a number of differences” between the two accident flight profiles, Ky says, “but also a large amount of similarities.”

Meanwhile, the FAA, which had remained largely silent since the Ethiopian accident, finally spoke up. Encouraged by news that ET302’s flight data recorder and cockpit voice recorders were recovered on March 11, the agency was holding out for more concrete data linking the two 737-8 accidents. “Thus far, our review shows no systemic performance issues and provides no basis to order grounding the aircraft,” FAA Acting Administrator Dan Elwell said late on March 12. Then, in what could be seen as a swipe at regulators grounding the new Boeing cash cow: “Nor have other civil aviation authorities provided data to us that would warrant action.”

The FAA’s stance stunned almost everyone outside of aviation and many within the industry, but it should not have. The agency’s approach to system-safety analysis, while often criticized as too deliberate, produces results. Challenged by a White House-led commission in 1997 to cut the commercial fatal accident rate by 80% in a decade, the FAA—through its Commercial Aviation Safety Team—met the deadline and beat the target. In 1994, following the crash of an ATR 42 near Chicago, the agency ran 300 wind-tunnel tests on a one-fifth-scale ATR 42’s wing, and high-speed ground tests with an actual aircraft within a month, before banning the type from operating in icing conditions.

Within hours of Elwell’s March 12 statement, however, everything would change. Data captured by Aireon’s space-based ADS-B system and refined by the company helped to establish ET302’s flight profile. The data, provided to the FAA, Transport Canada and investigators, showed a series of altitude changes that suggest ET302 was struggling like JT610 did.

The Canadians were convinced. They told their U.S. counterparts they would ground the MAX, and at 11 a.m. Canada EDT March 13, Transport Minister Marc Garneau told the world.

“We know what happened with the Lion Air flight,” Garneau said. “We wanted to see if the Ethiopian flight resembled it.” While the links between the two accidents “are not conclusive, there are similarities that exceed a certain threshold in our minds.”

He said that while the U.S. and Canada were in regular communication over the MAX issue, he did not know if the U.S. had the Aireon data, and could not say if Canada’s move would alter the U.S.’ thinking. Considering how close the countries and their regulators are, and the importance of communication during a major aviation accident probe, Garneau’s answers suggested disagreement between the FAA and Transport Canada.

“All I can say is that, based on the new information we got this morning, it was enough to cause us to make this decision,” he said. “The Americans will do their own thing.”

The U.S. followed suit 3 hr. later—with President Donald Trump making the announcement during a White House briefing called to discuss drug trafficking.

“We didn’t have to make this decision today. We could have delayed it,” Trump said. “We maybe didn’t have to make it at all. But I felt it was important both psychologically and in a lot of other ways.”

The chain of events made clear that the FAA wanted to wait for even more definitive data, but the White House had seen enough. The move left all 371 MAXs worldwide on the ground.

The FAA followed with a statement and emergency order that provided context.

“[The] investigation of the ET302 crash developed new information from the wreckage concerning the aircraft’s configuration just after takeoff that, taken together with newly refined data from satellite-based tracking of the aircraft’s flightpath, indicates some similarities between the [ET302 and JT610] accidents that warrant further investigation of the possibility of a shared cause for the two incidents that needs to be better understood and addressed,” the FAA says in its emergency order.

“Suffice it to say the evidence found on the ground made it more likely that the flightpath was closer to Lion Air,” Elwell says, referring to what would be confirmed as a stabilizer jackscrew trimmed nose-down.

The wreckage, and Aireon’s refined satellite data, helped U.S. and Canadian aviation safety experts present a clearer picture of ET302’s 6-min. flightpath.

“The way the [initial] data was presented, it was not showing credible movement of an aircraft,” Elwell says.

While neither U.S. nor Canadian officials would detail their findings, both said the resulting track, including ET302’s altitude variations, lined up closely with the JT610’s known track. This suggests ET302 was struggling to maintain altitude, and then dove rapidly to Earth.

“We are a fact-driven, data-based organization. We make actions based on data, findings and risk assessment,” Elwell says. “That data coalesced, and we made the call.”

He says the FAA’s reliance on the satellite data was in part due to uncertainty over delays in processing ET302’s FDR data.

“We had been hopeful all along that with black boxes discovered soon, that we could get them on the table and start pulling data,” Elwell says. “That process was lengthened more than I had hoped.”

The FAA’s order does not spell out the steps for getting the MAXs back in service. The agency confirmed that validation and installation of the flight-control system update being developed by Boeing in response to the JT610 findings will be part of the package. “We have not tied the [grounding] order specifically to the software patch,” Elwell says.

Preliminary analysis of data from ET302’s flight data and cockpit voice recorders was finished March 16. The next day, Ethiopia’s transport minister said the data provides the strongest evidence yet linking the two 737-8 accidents

“Our experts and U.S. experts have proven the accuracy of the information,” said Ethiopian Transport Minister Dagmawit Moges. “The Ethiopian government has absorbed the information. The cause of the crash was similar to that of Indonesia’s Flight 610.”

Investigators’ ability to link the MCAS to both accident sequences would further implicate the controversial system, which most pilots did not know existed prior to the JT610 accident and subsequent probe. But it also may expedite lifting the global MAX operations bans.

Boeing has been working on the flight-control modifications for months. If regulators determine the fixes and related training go far enough to reduce the MCAS’ risk and improve pilots’ understanding, the ban could be lifted without waiting for further progress in the ET302 probe.

Early indications are that, like the groundings, clearing the MAXs to resume operations will not be a unified effort.

EASA’s Ky says the agency wants to check each failure mode in detail before clearing the modified aircraft. “What we intend to do is to go in depth into the design, looking at the software and its interaction with the physical systems in the cockpit and the human-machine interface,” he says. “We will not only look at software changes, which are superficial, but everything behind it, including the [MCAS] architecture.”

“Whatever the FAA does,” EASA will not allow the 737 MAX to fly again until all questions have been answered, says Ky, adding that the bilateral aviation safety agreement meant to foster coordination also leaves room for independence.

“We hope to coordinate with our colleagues at the FAA, but we intend to do our work.”


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March 20, 2019 3:04 pm

U.S. Senate aviation panel to hold hearings with Boeing, FAA after fatal crashes

By Staff Reuters

WATCH: Boeing CEO says company determined to improve 737 MAX  https://globalnews.ca/news/5078096/boeing-faa-hearings-us-senate-subcommittee/


A U.S. Senate panel plans a hearing on March 27 on aviation safety after two fatal Boeing 737 MAX 8 aircraft crashes since October, and said it will also schedule a hearing with Boeing and other manufacturers, officials said on Wednesday.

READ MORE: Pentagon watchdog to probe whether acting defense secretary used office to promote Boeing

The hearing on federal oversight on commercial aviation by the Senate Commerce subcommittee on aviation and space will include the U.S. Federal Aviation Administration’s acting administrator Dan Elwell, National Transportation Safety Board chairman Robert Sumalt and Transportation Department Inspector General Calvin Scovel.

On Wednesday, the Seattle Times, citing unidentified sources familiar with the matter, reported the FBI was joining the criminal investigation into the MAX’s certification. The U.S. Justice Department is looking at the U.S. Federal Aviation Administration’s (FAA) oversight of Boeing, a person briefed on the matter said on Monday.

WATCH: Growing calls for an investigation into how the Boeing 737 MAX was deemed safe to fly in first place

 Meanwhile, the Pentagon Inspector General said on Wednesday it would investigate a complaint that Acting United States Secretary of Defense Patrick Shanahan, a former Boeing executive, violated ethical rules by allegedly promoting Boeing while in office.

Facing such high-profile scrutiny, Boeing, one of the United States’ most prestigious exporters, reshuffled executives in its commercial airplanes unit to focus on the crash fallout

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FBI joining criminal investigation into certification of Boeing 737 MAX
March 20, 2019 at 12:55 pm  - Updated March 20, 2019 at 1:29 pm

By Steve Miletich
Seattle Times staff reporter

The FBI has joined the criminal investigation into the certification of the Boeing 737 MAX, lending its considerable resources to an inquiry already being conducted by U.S. Department of Transportation agents, according to people familiar with the matter.

The federal grand jury investigation, based in Washington, D.C., is looking into the certification process that approved the safety of the new Boeing plane, two of which have crashed since October.

The FBI’s Seattle field office lies in proximity to Boeing’s 737 manufacturing plant in Renton, as well as nearby offices of Boeing and Federal Aviation Administration (FAA) officials involved in the certification of the plane.

The investigation, which is being overseen by the U.S. Justice Department’s criminal division and carried out by the Transportation Department’s Inspector General, began in response to information obtained after a Lion Air 737 MAX 8 crashed shortly after takeoff from Jakarta on Oct. 29, killing 189 people, Bloomberg reported earlier this week, citing an unnamed source.

It has widened since then, The Associated Press reported this week, with the grand jury issuing a subpoena on March 11 for information from someone involved in the plane’s development, one day after the crash of an Ethiopian Airlines 737 MAX 8 near Addis Ababa that killed 157 people.

The FBI’s support role was described by people on condition of anonymity because of the confidential nature of the investigation

Representatives of the Justice Department, the FBI and Transportation Department declined to comment, saying they could neither confirm nor deny an investigation.

A Seattle Times story over the weekend detailed how FAA managers pushed its engineers to delegate more of the certification process to Boeing itself. The Times story also detailed flaws in an original safety analysis that Boeing delivered to the FAA.

Criminal investigations into the federal oversight of airplane manufacturing and flight are rare, in part because of the longstanding belief that a civil-enforcement system better promotes candid reporting of concerns without fear of criminal repercussions.

Those criminal cases that have occurred have focused on false entries and misrepresentations.

In 1998, Transportation Department and FBI agents, acting on a whistleblower’s allegations, served a criminal search warrant on Alaska Airlines, seeking evidence of maintenance irregularities.

The investigation expanded to include the January 2000 crash of Alaska Flight 261 that killed 88 people, which the National Transportation Safety Board later blamed on the airline’s faulty maintenance practices and poor FAA oversight.

But no criminal charges were filed, although the FAA, in a separate administrative review, ultimately found that Alaska and three of its managers had violated safety regulations, fining the carrier $44,000, revoking the mechanic licenses of two of the managers and suspending the license of the third.

Federal criminal charges were brought over the May 11, 1996, ValuJet Flight 592 crash that took off from Miami International Airport and plunged into the Everglades minutes later, killing 110 people.

Federal prosecutors in Florida filed a 24-count indictment against SabreTech, an airline maintenance contractor, and its workers over alleged violations in the handling of oxygen containers blamed for the crash. SabreTech was found guilty on nine counts but was acquitted on conspiracy charges, according to news reports. An appeals court later overturned all but one of the counts, the improper training of employees.



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14 minutes ago, boestar said:

Just for curiosity sake how many hours did the entire operational fleet of 737-MAX8's accumulate prior to the Lion Air Crash?


First delivery was May 2017 to Malindo Air with 376 aircraft delivered globally. That would total a reasonable amount. 

Edited by blues deville
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boestar, of interest, from the WSJ story, "Inside U.S. Airlines’ Decisions to Keep Flying the 737 MAX":



Top leaders at American, which has 24 MAX 8 jets, and United, which was flying 14 MAX 9 planes, declined interview requests. American did provide two safety officials to discuss the airline’s decision to keep flying.

All three airlines say their decisions were largely data-driven. They routinely download thousands of data points from new aircraft like the MAX, and some began new monitoring to track performance of sensors suspected of contributing to the Oct. 29 crash of Lion Air Flight 610 in Indonesia.

Southwest’s Mr. Kelly says his internal, independent safety team was telling him that data collected from the MAX, which Southwest has been flying since 2017, showed no problem. (The airline flies 34 of those planes.)
. . .
And even if problems were to occur, Southwest pilots have been briefed on the system that was suspected of malfunctioning in both crashes and have routinely trained on steps to recover should the MAX’s computer mistakenly force the nose down. “These safety-management systems don’t speculate,” Mr. Kelly says.


How many hours for the worldwide fleet?

The MAX was delivered in the 2nd quarter 2017. Let us say 376 MAX's flew 8hrs/day.

~200 days in 2017

365 days in 2018

100 days in 2019

is ~665 days of MAX operation

X 8hrs/day

X 376 = ~2,000,000hrs

Minus say, 20% because not every airplane flies 8hrs/day for nearly 3 years...around ~1,600,000 hrs or so?


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March 21, 2019 / 8:34 AM / Updated an hour ago

Boeing to add extra safety alarm in 737 MAX jets: FT

(Reuters) - Boeing Co will install an extra safety alarm in the cockpits of all its 737 MAX aircraft after intense criticism in the wake of two fatal crashes, the Financial Times reported on Thursday.

The planemaker will include a warning light in the new 737 Max planes and retrofit all existing ones, according to the report.

The light will tell pilots if two key sensors do not agree, the FT reported, citing a person familiar with the situation.

Boeing did not immediately respond to a request for comment.

Shares of the company were down about 1 percent at $372.49 in morning trade


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Typical Boeing.

There was no specific CAB ALT warning annunciation on the 737 until after the Helios accident (the signal was the Take-Off warning horn above 10,000’)

Seems it always takes hull losses for Boeing to install equipment on a 737 that is basic or mandatory in any other Boeing aircraft designed after 1965.


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This version of the story goes into detail about what specific North American airlines had done with Boeing's "options" on this issue




Boeing’s optional safety features, in part, could have helped the pilots detect any erroneous readings. One of the optional upgrades, the angle of attack indicator, displays the readings of the two sensors. The other, called a disagree light, is activated if those sensors are at odds with one another.

Air Canada said Thursday its grounded Boeing 737 Max aircraft are equipped with both the angle of attack indicators and disagree lights that are used by the aircraft’s software system during flight to avert stalls.

Air Canada spokeswoman Isabelle Arthur says the airline purchased the features for its fleet of 24 Max 8 planes.

Boeing will soon update the MCAS software, and will also make the disagree light standard on all new 737 Max planes, according to a person familiar with the changes, who spoke on condition of anonymity because they have not been made public. The angle of attack indicator will remain an option that airlines can buy.

Neither feature was mandated by the Federal Aviation Administration. All 737 Max jets have been grounded.

“They’re critical, and cost almost nothing for the airlines to install,” said Bjorn Fehrm, an analyst at the aviation consultancy Leeham. “Boeing charges for them because it can. But they’re vital for safety.”

Earlier this week, Dennis A. Muilenburg, Boeing’s chief executive, said the company was working to make the 737 Max safer.

“As part of our standard practice following any accident, we examine our aircraft design and operation, and when appropriate, institute product updates to further improve safety,” he said in a statement.

Add-on features can be big money-makers for plane manufacturers.

In 2013, around the time Boeing was starting to market its 737 Max 8, an airline would expect to spend about $800,000 to $2 million on various options for such a narrow-body aircraft, according to a report by Jackson Square Aviation, a consultancy in San Francisco. That would be about 5 per cent of the plane’s final price.

Boeing charges extra, for example, for a backup fire extinguisher in the cargo hold. Past incidents have shown that a single extinguishing system may not be enough to put out flames that spread rapidly through the plane. Regulators in Japan require airlines there to install backup fire extinguishing systems, but the FAA does not.

“There are so many things that should not be optional, and many airlines want the cheapest airplane you can get,” said Mark H. Goodrich, an aviation lawyer and former engineering test pilot. “And Boeing is able to say, ‘Hey, it was available.’”

But what Boeing doesn’t say, he added, is that it has become “a great profit center” for the manufacturer.

Both Boeing and its airline customers have taken pains to keep these options, and prices, out of the public eye. Airlines frequently redact details of the features they opt to pay for — or exclude — from their filings with financial regulators. Boeing declined to disclose the full menu of safety features it offers as options on the 737 Max, or how much they cost.

But one unredacted filing from 2003 for a previous version of the 737 shows that Gol Airlines, a Brazilian carrier, paid $6,700 extra for oxygen masks for its crew, and $11,900 for an advanced weather radar system control panel. Gol did not immediately respond to a request for comment.

The three American airlines that bought the 737 Max each took a different approach to outfitting the cockpits.

American Airlines, which ordered 100 of the planes and has 24 in its fleet, bought both the angle of attack indicator and the disagree light, the company said.

Southwest Airlines, which ordered 280 of the planes and counts 36 in its fleet so far, had already purchased the disagree alert option, and it also installed an angle of attack indicator in a display mounted above the pilots’ heads. After the Lion Air crash, Southwest said it would modify its 737 Max fleet to place the angle of attack indicator on the pilots’ main computer screens.

United Airlines, which ordered 137 of the planes and has received 14, did not select the indicators or the disagree light. A United spokesman said the airline does not include the features because its pilots use other data to fly the plane.


Edited by dagger
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I am not sure I would call an AOA indicator "Critical"  How many aircraft have it now and if they do where is it displayed.  enerally it would be buried on the flight control page of the EICAS/ECAM system and not on a PFD.

I know in the Bombardier world there is a "Flight Test" page that can be displayed which shows the AOA as well as spoiler panel angles.  But this page is only used during flight test when the pilots routinely explore the flight envelope at or near the stall.   Once flight test is complete, access to the flight test display is removed.  We did have a couple of customers that requested it be left active however to access it you need to enter the correct key sequence on the panel, it's not just out there to look at.

concentrating on the AOA could very well distract the pilot from the correct course of action which would be to hit the cutoff switches.  If the plane is behaving badly in the pitch axis would it not be prudent to remove power to all things pitch related (except the elevators themselves).  


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Not very often do you hear airline pilots say they want more ground school and simulator training. A different situation with the Max problems but its generally considered to be as popular as a root canal procedure.



Edited by blues deville
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2 hours ago, blues deville said:

AC and WS have the optional system installed on their 737 Max aircraft. 


Thanks I took a look at the article and I see that WestJet only purchased the Light and not the angle of attack indicators which I guess, from boestars post,  are not critical.

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Garuda looks to scrap Boeing 737 Max 8 order after crashes

Image copyright Getty Images

Garuda Indonesia is seeking to scrap its multi-billion dollar order for 49 Boeing 737 Max 8 jets after the plane was involved in two fatal crashes.

The move is thought to be the first formal cancellation of an order for the aircraft.

A Garuda spokesperson said passengers had "lost trust" in the plane.

It comes as investigators work to establish the cause of a recent crash involving a 737 Max 8, which killed 157 people.

It was the second fatal disaster involving the jet in five months. A Lion Air flight crashed in October, killing 189 people.

"We have sent a letter to Boeing requesting that the order be cancelled," Garuda spokesman Ikhsan Rosan told AFP.

"The reason is that Garuda passengers in Indonesia have lost trust and no longer have the confidence" in the plane he said, adding that the airline was awaiting a response from Boeing.

Garuda did not immediately respond to a BBC request for comment. A spokesperson for Boeing was "unable to comment on customer discussions".

Garuda had already received one of the 737 Max 8 planes, AFP reported, part of a 50-plane order worth $4.9bn (£3.7bn) at list prices when it was announced in 2014.

Investigation ongoing

Garuda was among Boeing's customers that had indicated they could scrap their orders. for the 737 Max jets but the Indonesian airline appears the first to take action.

While there is no conclusive evidence so far that the Ethiopian Airlines and Lion Air disasters are linked, French experts analysing the Ethiopian Airlines' flight data black box say early investigations point to "clear similarities".

Experts believe a new automated system in Boeing's aircraft - intended to stop stalling by dipping the nose - may have played a role in both crashes, with pilots unable to override it.

The company said a software update is coming following the crash of the Lion Air flight.

Investigators intend to to issue a preliminary report into the Ethiopian Airlines disaster by mid-April.

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2 hours ago, boestar said:

I am not sure I would call an AOA indicator "Critical"  How many aircraft have it now and if they do where is it displayed.  enerally it would be buried on the flight control page of the EICAS/ECAM system and not on a PFD.

I know in the Bombardier world there is a "Flight Test" page that can be displayed which shows the AOA as well as spoiler panel angles.  But this page is only used during flight test when the pilots routinely explore the flight envelope at or near the stall.   Once flight test is complete, access to the flight test display is removed.  We did have a couple of customers that requested it be left active however to access it you need to enter the correct key sequence on the panel, it's not just out there to look at.

concentrating on the AOA could very well distract the pilot from the correct course of action which would be to hit the cutoff switches.  If the plane is behaving badly in the pitch axis would it not be prudent to remove power to all things pitch related (except the elevators themselves).  


The AoA indication is there on the PFD. The “eyebrows” in this picture are the “Pitch Level Indicator”, generated from the Flight Director, telling the pilot how close he is getting to a stall condition.


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The eyebrows are a “Pitch Limit Indicator”. It was added by Boeing as part of a package to assist in wind shear escape response.


The AOA gauge is a separate indication on the PFD.



Edited by rudder
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concentrating on the AOA could very well distract the pilot from the correct course of action which would be to hit the cutoff switches.  If the plane is behaving badly in the pitch axis would it not be prudent to remove power to all things pitch related (except the elevators themselves)

Regarding AOA and who has what feature.   I find the press coverage interesting.  Air Canada has a more comprehensive installation, yet the press articles start with 'Air Canada and Westjet' and downplay the role of the AOA indication.  I have to wonder, if the situation was reversed, would we see, 'Air Canada lacks important safety component'?

And nothing from Sunwing.  Hmm.

IMO the AOA indication's value depends a bit on the aircraft envelope.  The Citation I flew a million years ago had it, and it was a straight wing aircraft.  Far from being a distraction, I found it provided a great immediate reference in a number of situations.

For the MAX, the AOA location just becomes one more scan item.  The pilots I have spoken with about it have no issues  and are generally happy it's there.   Given what we now know about the link between AOA and unexpected aircraft behaviour, just having an 'AOA disagree' without an immediate visual indication of which AOA is saying what, that creates a period of confusion as to whether the failure is on the low side or the high.

Finally, the AOA indication is not going to be a distraction during an MCAS firing.  What it IS going to do is warn the pilots of an impending problem while they are still configured (flaps not yet retracted) so they can decide on a mitigation up front (leave the flaps out for a bit perhaps, so delay acceleration, get some altitude or stay configured and return, etc).

AOA indications are a good thing.  The customers who shelled out on their own to install them should get a credit from Boeing when the rest of the world gets them for free.

Finally, as soon as Boeing and the regulators start rolling out the fix, the grounding should shift from total airspace bans to unmodified aircraft and crew.  If we don't recognise investment in additional layers of safety, that investment will not continue, human nature being what it is.  The reasons for this grounding are ample proof of that sad fact.

All just my opinion.


Edited by Vsplat
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Once you get used to viewing normal AOA indications for phase of flight, you would quickly recognize an annomally. When accompanied by a miscompare message, diagnosing the problem would be much easier.

AOA indications are also available on some HGS modes (if installed).

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8 minutes ago, Vsplat said:

IMO the AOA indication's value depends a bit on the aircraft envelope.  The Citation I flew a million years ago had it, and it was a straight wing aircraft.  Far from being a distraction, I found it provided a great immediate reference in a number of situations.

I agree, the AOA indicator in the good old Gyration was a handy feature. We had one A320 at Skyservice that had AOA indicators - they were separate analog gauges just outside of each pilot's PFD. Interestingly, that aircraft was originally purchased by an operator in Europe who had them installed in their whole fleet. Sadly, that same operator decided to forego installing GPWS and ended up crashing one in Strasbourg - caused by another issue with the man-machine interface. 

Edited by J.O.
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