Boeing, and FAA oversight
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Yes. I agree.
I said
"What is at challenge is whether the negative slope on training and experience is suitably aligned with the positive slope on the capabilities of automation."
And you said
"the Max issue was a breakdown of man and machine; good people, but asked to do more than their capability (design / pilots), "
I think these are the same thing.
Yes. I agree.
I said
"What is at challenge is whether the negative slope on training and experience is suitably aligned with the positive slope on the capabilities of automation."
And you said
"the Max issue was a breakdown of man and machine; good people, but asked to do more than their capability (design / pilots), "
I think these are the same thing.
From Briefing.com
"Separately, Boeing (BA 341.43, +11.88, +3.6%) shares outperformed on reports that the FAA will approve the company's design fixes to the 737 MAX. New software flaws were discovered but the goal to return to service by mid-year remained intact, according to Bloomberg."
"Separately, Boeing (BA 341.43, +11.88, +3.6%) shares outperformed on reports that the FAA will approve the company's design fixes to the 737 MAX. New software flaws were discovered but the goal to return to service by mid-year remained intact, according to Bloomberg."
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https://mse238blog.stanford.edu/2017...pilot-systems/
This is where it is happening
This is where it is happening
FAA 'sounded positive', but …
From AWST 12 Feb
https://aviationweek.com/shownews/si...ax-ungrounding
Depending on how you wish to interpret what is reported:-
FAA 'sounded positive', "is narrowing issues"; i.e. not yet agreed.
'Are approaching a certification flight'; i.e. tests still in Boeing court - 'FAA still waiting for Boeing'.
'No rift between regulators', 'close alignment', - just differences.
P.S. Boeing view via Flight Global
https://www.flightglobal.com/singapo...136491.article
… concern that the regulatory un-grounding of the type will be staggered among jurisdictions, creating markets where the jet cannot be flown.
“There are a lot of regulators at the table,”. “We continue to work with them all across the world. Clearly we’re in a position where the FAA is the lead regulator, the regulator of record because of the US. We’re making sure that we understand step-by-step, task-by-task what we have to do. Then we’re taking those items and those tasks one by one, and working through them in a meticulous, thoughtful way.”
Re simulator training being a major issue.
“I see it having a minor impact in recurring training going forward,”. “Frankly it’s a simulator session and pilots are going to be in a simulator every six months. It will be a little bit of a cost and inconvenience as we get these airplanes back into service. But the airplane has been out of service for so long that Max pilots have to go through recurring training anyway. All-in-all [simulator training] is the right thing for us to do.”
P.P.S. Another view of the situation from NYT
https://www-nytimes-com.cdn.ampproje...again.amp.html
Certification flights 'late February or early March'.
Backtracking to the Max grounding; FAA position, somewhat tenuous.
https://www.flightglobal.com/program...136621.article
.
https://aviationweek.com/shownews/si...ax-ungrounding
Depending on how you wish to interpret what is reported:-
FAA 'sounded positive', "is narrowing issues"; i.e. not yet agreed.
'Are approaching a certification flight'; i.e. tests still in Boeing court - 'FAA still waiting for Boeing'.
'No rift between regulators', 'close alignment', - just differences.
P.S. Boeing view via Flight Global
https://www.flightglobal.com/singapo...136491.article
… concern that the regulatory un-grounding of the type will be staggered among jurisdictions, creating markets where the jet cannot be flown.
“There are a lot of regulators at the table,”. “We continue to work with them all across the world. Clearly we’re in a position where the FAA is the lead regulator, the regulator of record because of the US. We’re making sure that we understand step-by-step, task-by-task what we have to do. Then we’re taking those items and those tasks one by one, and working through them in a meticulous, thoughtful way.”
Re simulator training being a major issue.
“I see it having a minor impact in recurring training going forward,”. “Frankly it’s a simulator session and pilots are going to be in a simulator every six months. It will be a little bit of a cost and inconvenience as we get these airplanes back into service. But the airplane has been out of service for so long that Max pilots have to go through recurring training anyway. All-in-all [simulator training] is the right thing for us to do.”
P.P.S. Another view of the situation from NYT
https://www-nytimes-com.cdn.ampproje...again.amp.html
Certification flights 'late February or early March'.
Backtracking to the Max grounding; FAA position, somewhat tenuous.
https://www.flightglobal.com/program...136621.article
.
Last edited by safetypee; 12th Feb 2020 at 14:38. Reason: P.S. P.P.S.
SCC Final Report :-
Preaching to the converted?
The U.S. system for aircraft certification is robust and proven, and the FAA is a leader in augmenting aviation safety worldwide. This system also allows the United States to lead the world in the development and implementation of innovative products in order to enhance safety.
Boeing Fires Supervisor of Pilots Who Sent Embarrassing Emails
Completely in accordance with the Forbes article below.Questions are being raised about Boeings culture also after the failure of its Starliner spacecraft.
“It looks as if there could possibly be process issues at Boeing, and we want to understand what the culture is at Boeing that may have led to that,” he said.
Forbes article on Boeing culture.
However, while they (Boeing) claim that their training aims to “be responsive to emergent needs” and “be collaborative via a social component,” they fail to adequately respond to employee concerns and foster a spirit of collaboration within their own company. As a result, this has lead to the creation of a toxic company culture with employees whose voices remain unheard.For employees in general, Carnegie Mellon University professor Brandy Aven says: “There's often tension between ensuring safety and increasing profits, but when times are good, they can feel enormous pressure to stay quiet about safety concerns.”
Furthermore, there’s a tendency to avoid speaking up so that you don’t “get in the way of the success of the endeavors of the organization,” which is further exacerbated by the lack of channels available to employees to communicate these concerns in the first place.
Furthermore, there’s a tendency to avoid speaking up so that you don’t “get in the way of the success of the endeavors of the organization,” which is further exacerbated by the lack of channels available to employees to communicate these concerns in the first place.
Boeing Fires Supervisor of Pilots Who Sent Embarrassing Emails
https://uk.advfn.com/stock-market/NY...arras/81736701
https://uk.advfn.com/stock-market/NY...arras/81736701
Now they just have to go up the chain of command th whole way to the Chairman at that time, and get rid o the lot, that would be consistent with getting rid of a middle level manager who apparently was not a party to the text exchange that occurred. talk about scapegoats. If ever a group needed to be left on the aft boat deck listening to the quartet play "Nearer my God to Thee" it is BAC's board and senior management. They set the tone and accepted the practices that resulted.
Did the Chairman ever correct the behaviour of shooting the messengers of the 2003 QA debacle?
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https://mse238blog.stanford.edu/2017...pilot-systems/
This is where it is happening
This is where it is happening
Reuters is reporting Boeing and the FAA are at odds over some wiring in the MAX.
Is "It has worked fine so far" a valid analysis?
SEATTLE/WASHINGTON (Reuters) - Boeing Co told the U.S. Federal Aviation Administration it does not believe it needs to separate or move wiring bundles on its grounded 737 MAX jetliner that regulators have warned could short circuit with catastrophic consequences, people familiar with the matter said on Friday.The FAA confirmed Friday it had received a proposal from the planemaker regarding the wiring issue.
The FAA will “rigorously evaluate Boeing’s proposal to address a recently discovered wiring issue with the 737 MAX. The manufacturer must demonstrate compliance with all certification standards,” the agency said in a statement.
The U.S. planemaker and FAA first said in early January they were reviewing a wiring issue that could potentially cause a short circuit on the 737 MAX, and under certain circumstances lead to a crash if pilots did not react in time.
A Boeing spokesman referred all questions on wiring to the FAA, saying the agency would make the final decision and that the company is answering questions from the FAA.
[MCAS bla...]
There are more than a dozen different locations on the 737 MAX where wiring bundles may be too close together. Most of the locations are under the cockpit in an electrical bay.
If the bundles pose a potential hazard, regulations would typically require separating the bundles or adding a physical barrier.
Boeing has noted in talks with the FAA that the same wiring bundles are in the 737 NG, which has been in service since 1997 and logged 205 million flight hours without any wiring issues.
New safety rules on wiring were adopted in the aftermath of the 1998 Swiss Air 111 crash.
A company official told Reuters last month Boeing had been working on a design that would separate the wiring bundles, if necessary. Moving the bundles could pose further delays to the return of the MAX, however, and Reuters reported Thursday that a key certification test flight was not expected until April or later.
Three U.S. airlines this week pushed back the resumption of 737 MAX flights from June until August or later. Boeing has estimated U.S. officials would lift a safety ban on the aircraft around mid-year.
It is unclear whether the European Union Aviation Safety Agency will demand the MAX wiring bundles be separated. A spokeswoman for the agency on Thursday said regulators were “waiting for additional information from Boeing.”
Is "It has worked fine so far" a valid analysis?
Boeing tells FAA it does not believe 737 MAX wiring should be moved: sources
SEATTLE/WASHINGTON (Reuters) - Boeing Co told the U.S. Federal Aviation Administration it does not believe it needs to separate or move wiring bundles on its grounded 737 MAX jetliner that regulators have warned could short circuit with catastrophic consequences, people familiar with the matter said on Friday.The FAA confirmed Friday it had received a proposal from the planemaker regarding the wiring issue.
The FAA will “rigorously evaluate Boeing’s proposal to address a recently discovered wiring issue with the 737 MAX. The manufacturer must demonstrate compliance with all certification standards,” the agency said in a statement.
The U.S. planemaker and FAA first said in early January they were reviewing a wiring issue that could potentially cause a short circuit on the 737 MAX, and under certain circumstances lead to a crash if pilots did not react in time.
A Boeing spokesman referred all questions on wiring to the FAA, saying the agency would make the final decision and that the company is answering questions from the FAA.
[MCAS bla...]
There are more than a dozen different locations on the 737 MAX where wiring bundles may be too close together. Most of the locations are under the cockpit in an electrical bay.
If the bundles pose a potential hazard, regulations would typically require separating the bundles or adding a physical barrier.
Boeing has noted in talks with the FAA that the same wiring bundles are in the 737 NG, which has been in service since 1997 and logged 205 million flight hours without any wiring issues.
New safety rules on wiring were adopted in the aftermath of the 1998 Swiss Air 111 crash.
A company official told Reuters last month Boeing had been working on a design that would separate the wiring bundles, if necessary. Moving the bundles could pose further delays to the return of the MAX, however, and Reuters reported Thursday that a key certification test flight was not expected until April or later.
Three U.S. airlines this week pushed back the resumption of 737 MAX flights from June until August or later. Boeing has estimated U.S. officials would lift a safety ban on the aircraft around mid-year.
It is unclear whether the European Union Aviation Safety Agency will demand the MAX wiring bundles be separated. A spokeswoman for the agency on Thursday said regulators were “waiting for additional information from Boeing.”
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https://www.seattletimes.com/busines...boeing-missed/
FAA faces dilemma over 737 MAX wiring flaw that Boeing missed
Feb. 14, 2020 at 7:14 pm Updated Feb. 14, 2020 at 7:50 pm
By Dominic Gates
Seattle Times aerospace reporter
During the original design and certification of Boeing’s 737 MAX, company engineers didn’t notice that the electrical wiring doesn’t meet federal aviation regulations for safe wire separation. And the Federal Aviation Administration (FAA) failed to detect Boeing’s miss.
The wiring vulnerability creates the theoretical potential for an electrical short to move the jet’s horizontal tail uncommanded by the pilot, which could be catastrophic. If that were to happen, it could lead to a flight control emergency similar to the one that brought down two MAX jets, causing 346 deaths and the grounding of the aircraft.
Because this danger is extremely remote, the FAA faces a dilemma over what to do about it. The issue has complicated the return of the MAX to service after a grounding that is edging close to one year.
Modifying the wiring would be a delicate and expensive task, and Boeing this week submitted a proposal to the FAA, arguing that it shouldn’t be required.
Yet allowing the wiring to remain as is will be difficult at a time when both Boeing and the FAA are under tremendous scrutiny.
Boeing’s argument rests on the long service history of the earlier model 737, which has the same wiring. That earlier 737 NG model didn’t have to meet the current wiring-separation standards because they came into force long after that jet was certified.
“There are 205 million flight hours in the 737 fleet with this wiring type,” a Boeing official said. “There have been 16 failures in service, none of which were applicable to this scenario. We’ve had no hot shorts.”
In addition, Boeing says pulling out and rerouting wires on the almost 800 MAXs already built would pose a potentially higher risk of causing an electrical short, because insulation could chafe or crack in the process of moving the wires.
However, an FAA safety engineer familiar with the issue, who asked not to be identified because he spoke without agency permission, said agency technical staff have been clear that the wiring doesn’t comply with regulations and have told their Boeing counterparts it has to be fixed.
A second person familiar with the FAA’s thinking said the agency has communicated to Boeing that despite the safe service history of the wiring on other 737s, it will be difficult to convince regulators that they should do nothing.
“Our people have to weigh that against the regulations and the political and public opinion risk of appearing to give Boeing a break on a regulation that’s there for a reason,” the second person said.
Furthermore, there’s also pressure from foreign regulators, including the European Union Aviation Safety Agency (EASA).
“It’s probably true that if Boeing proposes to do nothing, EASA is going to say, ‘Hell, no,'” the second person said.
Jeff Guzzetti, a former accident investigator with both the FAA and the National Transportation Safety Board (NTSB), and now an air-safety consultant, said the federal agency’s decision “will be influenced by the white-hot spotlight the FAA is under” because of the MAX crashes.
Whatever decision it ultimately makes, he said, “The FAA better have a strong case.”
On Friday, the FAA issued an official statement hinting that Boeing may be forced to comply with the wiring regulation.
“We will rigorously evaluate Boeing’s proposal to address a recently discovered wiring issue with the 737 MAX,” the FAA said. “The manufacturer must demonstrate compliance with all certification standards.”
Boeing spokesman Gordon Johndroe said that the entire range of possible options — from doing nothing to moving the wires — was considered and built into Boeing’s schedule adjustment last month.
Johndroe said that whatever decision the FAA makes “will not change the company’s estimate for the MAX returning to service by the middle of the year.”
A remote possibility
Boeing discovered the wiring vulnerabilities and informed the FAA of the problem when, after the crashes, it undertook a complete redo of its system safety analysis on the MAX, a painstaking look at all the possible system and equipment failures and the impact of each.
It was forced to do the new analysis when it realized the MAX’s original certification analysis included assumptions about pilot reaction times that didn’t match the reality of the responses during the two MAX crashes.
It’s unclear how during the design of the MAX Boeing missed the fact that the wiring didn’t meet the regulation governing separation of wires to prevent shorts.
The regulation was introduced in 2009 following study of two fatal crashes: TWA 800 in 1996, in which an electrical short is believed to have caused a spark in the fuel tank and an explosion; and Swissair 111 in 1998, when an electrical short caused a fire in the cockpit.
The FAA safety engineer said Boeing identified about a dozen positions in the 737 wiring, including one toward the jet’s tail and the rest in the electronics bay under the forward fuselage, where “significant runs of wire” failed to meet the new separation standard. The wire lengths involved were as long as 16 feet, he said.
In one instance, engineers found a hot power wire that was too close to two command wires running to the jet’s moveable horizontal tail, or stabilizer, one for commanding the tail to swivel to move the jet nose-up, the other to move it nose-down. The danger is a short that causes arcing of electricity from the hot wire to the command wire.
“If a hot short occurs between the power wire and either the up or down command wire, the stabilizer can go to the full nose-up or nose-down position,” the engineer said.
Furthermore, the electrical power in that wire could circumvent the cutoff switches in the cockpit that, in the event of such a stabilizer runaway, are used to kill electrical power to the tail. Theoretically, the pilots could be unable to shut it off.
This is unrelated to the flight control system — the Maneuvering Characteristics Augmentation System (MCAS) — that repeatedly forced down the noses of the two MAXs that crashed. However, the similarity in the potential outcome is enough to raise alarm.
The engineer described this as “a semi-remote possibility.” Boeing’s position, based on the 205 million safe flight hours on the earlier 737 where this has never happened, is that this is extremely remote.
However, the danger is scientifically established.
Michael Traskos, chairman of the industry’s wiring and cable standards committee and president of Lectromec, a Virginia-based laboratory and engineering firm specializing in wire-system component testing and consulting, said that his team did testing for NASA in 2005 and 2006, not specific to a particular airplane, “that demonstrated potential uncommanded activation in the event of arcing.”
How the FAA handles a noncompliance
Discovering that an airplane doesn’t meet all the safety regulations is not rare, and if it wasn’t for the MAX crisis it’s highly unlikely this wiring issue would have risen to attention.
In 2015, Douglas Anderson, the FAA’s deputy counsel in the Seattle-area regional office, wrote a critical internal white paper — “Achieving Compliance with Airworthiness Standards”— arguing that the agency in effect encourages manufacturers to be loose about complying with all the safety regulations because it doesn’t slap them hard when it’s discovered after a plane is certified that the design does not comply.
He noted that if there is a clear safety of flight issue, the FAA will issue an airworthiness directive requiring that the problem be fixed within a set timeframe. But absent that order, it’s left to the manufacturer to decide what to do.
Unless there is some clear flight-safety issue, he wrote, jet manufacturers “usually have no obligation to correct noncompliances, and it’s faster and cheaper to develop designs if compliance is not a priority.”
“There is rarely any significant consequence” for the airplane manufacturer, who is “free to correct the noncompliance at its convenience without threatening delivery schedules.”
He noted that 2011, a year when Boeing certified two new airplanes, saw a spike in discoveries of designs failing to comply with requirements, with 98 non-compliances found in the 787 Dreamliner and 24 non-compliances in the 747-8 jumbo jet.
“Fully compliant and substantiated designs require more time and resources,” Anderson wrote.
Anderson recommended manufacturers be held to account and forced to make fixes, the expense of which would deter coming out with non-compliant designs.
During certification of the MAX, Boeing persuaded the FAA to exempt it from meeting certain regulations, arguing that the plane was a derivative of a much earlier design and that the cost of upgrading to meet the latest regulations would outweigh the safety benefit.
For instance, during the original MAX certification, the FAA allowed Boeing not to further separate the cables to the rudder in the tail to ensure redundancy and not to meet the latest requirements for crew alerting systems.
If Boeing back in 2017 had asked the FAA for a pass on this wiring separation requirement, on the basis of the safe flight history of the earlier model, it would almost certainly have been granted more readily than the rudder cable exception.
Assessing the risk
But Boeing didn’t ask for it then, because somehow it missed the problem entirely.
Guzzetti, the safety investigator, said that although the system safety analysis was delegated to Boeing, this reveals a failure too in FAA oversight.
“How did it go undetected?” he asked. “Delegation doesn’t give the FAA a complete pass.”
Traskos, the wiring standards expert, said that leaving aside the current pressures on the FAA and Boeing, the decision on what to do now should “come down to identifying the level of risk.”
“If they identify that the failure severity is not that great, not catastrophic, and the failure probability is low, they could potentially justify maintaining the system as is,” he said. “I believe that’s something both sides would agree to.”
The FAA safety engineer said the agency will have to perform a formal risk analysis called a TARAM — a Transport Airplane Risk Assessment Methodology — to determine what type of fix is required and how soon.
Since the wiring is the same on the earlier 737 NG model, the question arises whether any wiring modification might also be needed on those aircraft, of which there are more than 6,000 flying worldwide.
However, the second person familiar with the FAA’s thinking said a TARAM is unlikely to recommend any change to the wiring on the NG. He said the risk of breaking apart wiring on thousands of much older airplanes would almost certainly be greater than the risk from leaving the wiring as is.
“You run a greater risk of introducing a short on older airplanes by going in and messing with it,” he said. “We even have people within the FAA concerned about breaking apart the wiring on the new MAXs.”
Guzzetti said discovering the wiring vulnerability so late and after two crashes makes it a harder call than if Boeing had asked for an exception during the jet’s original certification.
“They realize only now they have a problem with the wiring and they want forgiveness,” Guzzetti said. “It’s going to have to be well-documented and justified.”
Dominic Gates: 206-464-2963 or [email protected]; on Twitter: @dominicgates.
Feb. 14, 2020 at 7:14 pm Updated Feb. 14, 2020 at 7:50 pm
By Dominic Gates
Seattle Times aerospace reporter
During the original design and certification of Boeing’s 737 MAX, company engineers didn’t notice that the electrical wiring doesn’t meet federal aviation regulations for safe wire separation. And the Federal Aviation Administration (FAA) failed to detect Boeing’s miss.
The wiring vulnerability creates the theoretical potential for an electrical short to move the jet’s horizontal tail uncommanded by the pilot, which could be catastrophic. If that were to happen, it could lead to a flight control emergency similar to the one that brought down two MAX jets, causing 346 deaths and the grounding of the aircraft.
Because this danger is extremely remote, the FAA faces a dilemma over what to do about it. The issue has complicated the return of the MAX to service after a grounding that is edging close to one year.
Modifying the wiring would be a delicate and expensive task, and Boeing this week submitted a proposal to the FAA, arguing that it shouldn’t be required.
Yet allowing the wiring to remain as is will be difficult at a time when both Boeing and the FAA are under tremendous scrutiny.
Boeing’s argument rests on the long service history of the earlier model 737, which has the same wiring. That earlier 737 NG model didn’t have to meet the current wiring-separation standards because they came into force long after that jet was certified.
“There are 205 million flight hours in the 737 fleet with this wiring type,” a Boeing official said. “There have been 16 failures in service, none of which were applicable to this scenario. We’ve had no hot shorts.”
In addition, Boeing says pulling out and rerouting wires on the almost 800 MAXs already built would pose a potentially higher risk of causing an electrical short, because insulation could chafe or crack in the process of moving the wires.
However, an FAA safety engineer familiar with the issue, who asked not to be identified because he spoke without agency permission, said agency technical staff have been clear that the wiring doesn’t comply with regulations and have told their Boeing counterparts it has to be fixed.
A second person familiar with the FAA’s thinking said the agency has communicated to Boeing that despite the safe service history of the wiring on other 737s, it will be difficult to convince regulators that they should do nothing.
“Our people have to weigh that against the regulations and the political and public opinion risk of appearing to give Boeing a break on a regulation that’s there for a reason,” the second person said.
Furthermore, there’s also pressure from foreign regulators, including the European Union Aviation Safety Agency (EASA).
“It’s probably true that if Boeing proposes to do nothing, EASA is going to say, ‘Hell, no,'” the second person said.
Jeff Guzzetti, a former accident investigator with both the FAA and the National Transportation Safety Board (NTSB), and now an air-safety consultant, said the federal agency’s decision “will be influenced by the white-hot spotlight the FAA is under” because of the MAX crashes.
Whatever decision it ultimately makes, he said, “The FAA better have a strong case.”
On Friday, the FAA issued an official statement hinting that Boeing may be forced to comply with the wiring regulation.
“We will rigorously evaluate Boeing’s proposal to address a recently discovered wiring issue with the 737 MAX,” the FAA said. “The manufacturer must demonstrate compliance with all certification standards.”
Boeing spokesman Gordon Johndroe said that the entire range of possible options — from doing nothing to moving the wires — was considered and built into Boeing’s schedule adjustment last month.
Johndroe said that whatever decision the FAA makes “will not change the company’s estimate for the MAX returning to service by the middle of the year.”
A remote possibility
Boeing discovered the wiring vulnerabilities and informed the FAA of the problem when, after the crashes, it undertook a complete redo of its system safety analysis on the MAX, a painstaking look at all the possible system and equipment failures and the impact of each.
It was forced to do the new analysis when it realized the MAX’s original certification analysis included assumptions about pilot reaction times that didn’t match the reality of the responses during the two MAX crashes.
It’s unclear how during the design of the MAX Boeing missed the fact that the wiring didn’t meet the regulation governing separation of wires to prevent shorts.
The regulation was introduced in 2009 following study of two fatal crashes: TWA 800 in 1996, in which an electrical short is believed to have caused a spark in the fuel tank and an explosion; and Swissair 111 in 1998, when an electrical short caused a fire in the cockpit.
The FAA safety engineer said Boeing identified about a dozen positions in the 737 wiring, including one toward the jet’s tail and the rest in the electronics bay under the forward fuselage, where “significant runs of wire” failed to meet the new separation standard. The wire lengths involved were as long as 16 feet, he said.
In one instance, engineers found a hot power wire that was too close to two command wires running to the jet’s moveable horizontal tail, or stabilizer, one for commanding the tail to swivel to move the jet nose-up, the other to move it nose-down. The danger is a short that causes arcing of electricity from the hot wire to the command wire.
“If a hot short occurs between the power wire and either the up or down command wire, the stabilizer can go to the full nose-up or nose-down position,” the engineer said.
Furthermore, the electrical power in that wire could circumvent the cutoff switches in the cockpit that, in the event of such a stabilizer runaway, are used to kill electrical power to the tail. Theoretically, the pilots could be unable to shut it off.
This is unrelated to the flight control system — the Maneuvering Characteristics Augmentation System (MCAS) — that repeatedly forced down the noses of the two MAXs that crashed. However, the similarity in the potential outcome is enough to raise alarm.
The engineer described this as “a semi-remote possibility.” Boeing’s position, based on the 205 million safe flight hours on the earlier 737 where this has never happened, is that this is extremely remote.
However, the danger is scientifically established.
Michael Traskos, chairman of the industry’s wiring and cable standards committee and president of Lectromec, a Virginia-based laboratory and engineering firm specializing in wire-system component testing and consulting, said that his team did testing for NASA in 2005 and 2006, not specific to a particular airplane, “that demonstrated potential uncommanded activation in the event of arcing.”
How the FAA handles a noncompliance
Discovering that an airplane doesn’t meet all the safety regulations is not rare, and if it wasn’t for the MAX crisis it’s highly unlikely this wiring issue would have risen to attention.
In 2015, Douglas Anderson, the FAA’s deputy counsel in the Seattle-area regional office, wrote a critical internal white paper — “Achieving Compliance with Airworthiness Standards”— arguing that the agency in effect encourages manufacturers to be loose about complying with all the safety regulations because it doesn’t slap them hard when it’s discovered after a plane is certified that the design does not comply.
He noted that if there is a clear safety of flight issue, the FAA will issue an airworthiness directive requiring that the problem be fixed within a set timeframe. But absent that order, it’s left to the manufacturer to decide what to do.
Unless there is some clear flight-safety issue, he wrote, jet manufacturers “usually have no obligation to correct noncompliances, and it’s faster and cheaper to develop designs if compliance is not a priority.”
“There is rarely any significant consequence” for the airplane manufacturer, who is “free to correct the noncompliance at its convenience without threatening delivery schedules.”
He noted that 2011, a year when Boeing certified two new airplanes, saw a spike in discoveries of designs failing to comply with requirements, with 98 non-compliances found in the 787 Dreamliner and 24 non-compliances in the 747-8 jumbo jet.
“Fully compliant and substantiated designs require more time and resources,” Anderson wrote.
Anderson recommended manufacturers be held to account and forced to make fixes, the expense of which would deter coming out with non-compliant designs.
During certification of the MAX, Boeing persuaded the FAA to exempt it from meeting certain regulations, arguing that the plane was a derivative of a much earlier design and that the cost of upgrading to meet the latest regulations would outweigh the safety benefit.
For instance, during the original MAX certification, the FAA allowed Boeing not to further separate the cables to the rudder in the tail to ensure redundancy and not to meet the latest requirements for crew alerting systems.
If Boeing back in 2017 had asked the FAA for a pass on this wiring separation requirement, on the basis of the safe flight history of the earlier model, it would almost certainly have been granted more readily than the rudder cable exception.
Assessing the risk
But Boeing didn’t ask for it then, because somehow it missed the problem entirely.
Guzzetti, the safety investigator, said that although the system safety analysis was delegated to Boeing, this reveals a failure too in FAA oversight.
“How did it go undetected?” he asked. “Delegation doesn’t give the FAA a complete pass.”
Traskos, the wiring standards expert, said that leaving aside the current pressures on the FAA and Boeing, the decision on what to do now should “come down to identifying the level of risk.”
“If they identify that the failure severity is not that great, not catastrophic, and the failure probability is low, they could potentially justify maintaining the system as is,” he said. “I believe that’s something both sides would agree to.”
The FAA safety engineer said the agency will have to perform a formal risk analysis called a TARAM — a Transport Airplane Risk Assessment Methodology — to determine what type of fix is required and how soon.
Since the wiring is the same on the earlier 737 NG model, the question arises whether any wiring modification might also be needed on those aircraft, of which there are more than 6,000 flying worldwide.
However, the second person familiar with the FAA’s thinking said a TARAM is unlikely to recommend any change to the wiring on the NG. He said the risk of breaking apart wiring on thousands of much older airplanes would almost certainly be greater than the risk from leaving the wiring as is.
“You run a greater risk of introducing a short on older airplanes by going in and messing with it,” he said. “We even have people within the FAA concerned about breaking apart the wiring on the new MAXs.”
Guzzetti said discovering the wiring vulnerability so late and after two crashes makes it a harder call than if Boeing had asked for an exception during the jet’s original certification.
“They realize only now they have a problem with the wiring and they want forgiveness,” Guzzetti said. “It’s going to have to be well-documented and justified.”
Dominic Gates: 206-464-2963 or [email protected]; on Twitter: @dominicgates.
Boeing's response to many things is the NG's safety record.
They fail to acknowledge the MAX's extremely poor safety record.
The MAX is not an NG and it should be called out as that - The NG has proven with 205 million flying hours a safe aircraft for low trained crews all over the world.
The MAX has proven it is not as safe as the NG for the same crews.
What has happened to that fix that was ready many months ago? Why not release any details including bare airframe flight data? How does the new data compare of the two FC's work?
Should the MAX be a 3 crew aircraft? that is the only MCAS event that was successful!
Are the NG and MAX actual manual trim wheel forces the same or is the MAX even harder to move as the aircraft moves out of trim?
Mid Feb now and no new leaked bare airframe data leaked from all the persons and regulators involved suggests that is still Boeing's secret data. I expect we will get a few more bombshells between now and mid-year.
I think this saga has a lot longer to run.
They fail to acknowledge the MAX's extremely poor safety record.
The MAX is not an NG and it should be called out as that - The NG has proven with 205 million flying hours a safe aircraft for low trained crews all over the world.
The MAX has proven it is not as safe as the NG for the same crews.
What has happened to that fix that was ready many months ago? Why not release any details including bare airframe flight data? How does the new data compare of the two FC's work?
Should the MAX be a 3 crew aircraft? that is the only MCAS event that was successful!
Are the NG and MAX actual manual trim wheel forces the same or is the MAX even harder to move as the aircraft moves out of trim?
Mid Feb now and no new leaked bare airframe data leaked from all the persons and regulators involved suggests that is still Boeing's secret data. I expect we will get a few more bombshells between now and mid-year.
I think this saga has a lot longer to run.
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"Boeing’s argument rests on the long service history of the earlier model 737, which has the same wiring. That earlier 737 NG model didn’t have to meet the current wiring-separation standards because they came into force long after that jet was certified. Boeing’s argument rests on the long service history of the earlier model 737, which has the same wiring. That earlier 737 NG model didn’t have to meet the current wiring-separation standards because they came into force long after that jet was certified." (from Seattle Times article)
Not sure who's feeding the reporter that line, but it's not true. It's a single failure that's potentially catastrophic (a hot short to the stab motor wiring). The system safety analysis regulations and policy applicable at the time of the NG application prohibited such a vulnerability. Someone is likely trying to give the impression it is EWIS issue under the relatively new (2007) 14 CFR 25.1707 and 1709 requirements, but it is also non-compliant with the long standing system safety requirements of 25.1309(b), which applied to the NG. Wire separation has always been an element of preventing catastrophic single failures under 25.1309.
Not sure who's feeding the reporter that line, but it's not true. It's a single failure that's potentially catastrophic (a hot short to the stab motor wiring). The system safety analysis regulations and policy applicable at the time of the NG application prohibited such a vulnerability. Someone is likely trying to give the impression it is EWIS issue under the relatively new (2007) 14 CFR 25.1707 and 1709 requirements, but it is also non-compliant with the long standing system safety requirements of 25.1309(b), which applied to the NG. Wire separation has always been an element of preventing catastrophic single failures under 25.1309.
All of the wiring compliance issues, and the attendant regulator insistence on compliance are the price Boeing pays for the earlier gaming of the system. Zero sympathy, despite the merits of the technological and statistical arguments.
