MAX’s Return Delayed by FAA Reevaluation of 737 Safety Procedures
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https://www.seattletimes.com/busines...87-dreamliner/
New questions raised on safety of both 737 MAX and 787 Dreamliner
Nov. 7, 2019 at 6:19 pm Updated Nov. 7, 2019 at 6:26 pm
By Dominic Gates
Seattle Times aerospace reporter
Lawmakers are pursuing new safety issues with two Boeing jets — the 737 MAX and the 787 Dreamliner — and questioning how in each case managers at the Federal Aviation Administration (FAA) backed Boeing’s contention that there was no cause for concern despite objections from the safety agency’s own technical experts.
The revelations, contained in a letter from the leaders of the U.S. House Committee on Transportation and Infrastructure, come a week after they chaired an intense public hearing when Boeing CEO Dennis Muilenburg was grilled about the 737 MAX crashes in Indonesia and Ethiopia that killed 346 people.
The letter sent Thursday cites “serious, potentially catastrophic safety concerns raised by FAA technical specialists that FAA management ultimately overruled after Boeing objected.”
The issues came to light during the House investigation into the accidents but are unrelated to the two crashes. However, they will add to doubts about the independence of the FAA and its oversight of Boeing.
One issue is how FAA managers agreed during certification of the 737 MAX to give Boeing a pass on complying with a safety rule that requires more separation between duplicate sets of cables that control the jet’s rudder.
This is to avoid the possibility that shrapnel from an uncontained engine blowout could sever all the cables and render the plane uncontrollable.
The requirement was introduced when such a blowout caused the deadly 1989 crash of a United Airlines DC-10 in Sioux City, Iowa. The 737 has never been brought into line with the requirement, and when Boeing updated to the 737 MAX it argued once again that design “changes would be impractical” and expressed concern about the potential impact on “resources and program schedules,” according to documents submitted to the FAA.
At least six FAA specialists refused to concur with an agency paper that allowed Boeing to claim compliance “without implementing a design change,” and an FAA review panel in January 2017 rejected Boeing’s position that design changes were impractical.
Nevertheless, the FAA certified the MAX for passenger service in March that year, and three months later the FAA formally upheld the controversial paper and waved aside the concern among its own technical staff.
Dreamliners and lightning
The letter to FAA Administrator Stephen Dickson was sent by Rep. Peter DeFazio (D-Ore.), Chair of the House transportation committee, and Rick Larsen (D-Everett) Chair of the Subcommittee on Aviation.
The second concern they cite is a design change to the 787 Dreamliner that removed from the leading edge of the jet’s wings a layer of copper foil designed to protect against a lightning strike.
A plane such as the 787 that has a carbon-composite rather than a metal airframe is particularly vulnerable to lightning damage, and a thin layer of copper foil is embedded in areas under the surface of the skin where lightning strikes are common — especially on the wings, which are full of jet fuel — to disperse the energy.
In February this year, the FAA office that oversees and certifies Boeing’s designs rejected the removal of the foil from the wing edge. Boeing appealed.
DeFazio’s letter says that five days later, a company official in a meeting reportedly said that the matter had been discussed with the FAA’s Associate Administrator for Aviation Safety, Ali Bahrami. Bahrami has been criticized for his close ties to the aviation manufacturers that the agency oversees.
Two days after that meeting, FAA management reversed course, and accepted Boeing’s position that the change was acceptable, according to FAA documents.
DeFazio demands to know what the FAA is doing “to ensure that these two issues do not pose a risk to the flying public.”
Boeing issued a statement saying it is “aware of both issues raised in Chairman DeFazio’s letter.”
“We are confident that each was properly considered and addressed by Boeing, thoroughly reviewed with and approved by the FAA,” Boeing states.
An FAA spokesman declined to comment, saying that the agency will respond directly to the two legislators.
Legacy 737 design details
The shortcoming in the rudder cable design was cited in a Seattle Times story in May among a list of MAX design elements that don’t meet the latest FAA requirements.
The story listed a series of legacy design details that have been repeatedly grandfathered into the latest model each time Boeing has updated the 737, which was originally certified more than 50 years ago.
All the issues in the list were flagged by FAA safety engineers as requiring fixes before the MAX could be certified. But each was waved through after managers on the Boeing side of certification insisted that these were non-issues and managers on the FAA side agreed to let it move ahead with the requirement unaddressed.
In the case of the rudder cables, Boeing argued that the CFM-56 engine on the prior 737 model had an “excellent” service history and that it expected the new LEAP engines on the 737 MAX to have a similarly low rate of uncontained engine failures.
DeFazio and Larsen reject this argument as “nonsensical,” since it extrapolates on “the reliability of a then-unproven new engine based on the performance of a completely different older engine.”
DeFazio adds that “my staff has been told that it was virtually unprecedented for six or more FAA specialists to jointly non-concur on a single issue, highlighting the gravity of their concerns regarding the rudder cable issue.”
End runs around safety
Lightning strikes on aircraft are routine. In certain parts of the world, such as Florida and Japan, they are common.
To highlight the seriousness of the issue for the Dreamliner, DeFazio cites the example of a British Airways 787 struck by lightning two years ago shortly after it departed London’s Heathrow airport bound for India.
The plane continued its nine-hour flight but when the aircraft landed in Chennai, maintenance technicians discovered an unusual level of damage: more than 40 holes in the fuselage from the lightning strike.
The major danger from a strike is that if it were to penetrate the wing skin it could ignite the fuel vapor inside the wing, which acts as a fuel tank. When the 787 was designed as a carbon composite airframe, the FAA added a special condition requiring various design details to avoid such an explosion.
In addition to the copper foil that dissipates the energy, metal fasteners on the wing are sealed so that there is no direct metal channel all the way through from the outside to the inside of the wing skin.
That said, later the FAA also loosened a more stringent requirement established after the explosion of TWA 800 to prevent a fuel tank explosion. Bahrami, then head of the FAA’s Seattle office, led that rule change. He argued that manufacturers had found it impractical to comply.
DeFazio’s letter notes that the FAA just last month asked Boeing to perform a “risk assessment of the fuel tank explosion risk from lightning related ignition sources” on the 787 and “to determine if any corrective actions to reduce the risk of a fuel tank explosion should be required.”
However, it laments that this action is so late.
And DeFazio adds that “Boeing reportedly produced approximately 40 airplanes prior to the FAA’s approval of the design change.” He says this “suggests either willful neglect of the Federal aviation regulatory structure or an oversight system in need of desperate repair.”
His letter asks what the safety regulator is doing “ensure that manufacturers do not have an incentive to attempt end-runs around FAA technical specialists by going to senior FAA management.”
Dominic Gates: 206-464-2963 or [email protected]; on Twitter: @dominicgates.
Nov. 7, 2019 at 6:19 pm Updated Nov. 7, 2019 at 6:26 pm
By Dominic Gates
Seattle Times aerospace reporter
Lawmakers are pursuing new safety issues with two Boeing jets — the 737 MAX and the 787 Dreamliner — and questioning how in each case managers at the Federal Aviation Administration (FAA) backed Boeing’s contention that there was no cause for concern despite objections from the safety agency’s own technical experts.
The revelations, contained in a letter from the leaders of the U.S. House Committee on Transportation and Infrastructure, come a week after they chaired an intense public hearing when Boeing CEO Dennis Muilenburg was grilled about the 737 MAX crashes in Indonesia and Ethiopia that killed 346 people.
The letter sent Thursday cites “serious, potentially catastrophic safety concerns raised by FAA technical specialists that FAA management ultimately overruled after Boeing objected.”
The issues came to light during the House investigation into the accidents but are unrelated to the two crashes. However, they will add to doubts about the independence of the FAA and its oversight of Boeing.
One issue is how FAA managers agreed during certification of the 737 MAX to give Boeing a pass on complying with a safety rule that requires more separation between duplicate sets of cables that control the jet’s rudder.
This is to avoid the possibility that shrapnel from an uncontained engine blowout could sever all the cables and render the plane uncontrollable.
The requirement was introduced when such a blowout caused the deadly 1989 crash of a United Airlines DC-10 in Sioux City, Iowa. The 737 has never been brought into line with the requirement, and when Boeing updated to the 737 MAX it argued once again that design “changes would be impractical” and expressed concern about the potential impact on “resources and program schedules,” according to documents submitted to the FAA.
At least six FAA specialists refused to concur with an agency paper that allowed Boeing to claim compliance “without implementing a design change,” and an FAA review panel in January 2017 rejected Boeing’s position that design changes were impractical.
Nevertheless, the FAA certified the MAX for passenger service in March that year, and three months later the FAA formally upheld the controversial paper and waved aside the concern among its own technical staff.
Dreamliners and lightning
The letter to FAA Administrator Stephen Dickson was sent by Rep. Peter DeFazio (D-Ore.), Chair of the House transportation committee, and Rick Larsen (D-Everett) Chair of the Subcommittee on Aviation.
The second concern they cite is a design change to the 787 Dreamliner that removed from the leading edge of the jet’s wings a layer of copper foil designed to protect against a lightning strike.
A plane such as the 787 that has a carbon-composite rather than a metal airframe is particularly vulnerable to lightning damage, and a thin layer of copper foil is embedded in areas under the surface of the skin where lightning strikes are common — especially on the wings, which are full of jet fuel — to disperse the energy.
In February this year, the FAA office that oversees and certifies Boeing’s designs rejected the removal of the foil from the wing edge. Boeing appealed.
DeFazio’s letter says that five days later, a company official in a meeting reportedly said that the matter had been discussed with the FAA’s Associate Administrator for Aviation Safety, Ali Bahrami. Bahrami has been criticized for his close ties to the aviation manufacturers that the agency oversees.
Two days after that meeting, FAA management reversed course, and accepted Boeing’s position that the change was acceptable, according to FAA documents.
DeFazio demands to know what the FAA is doing “to ensure that these two issues do not pose a risk to the flying public.”
Boeing issued a statement saying it is “aware of both issues raised in Chairman DeFazio’s letter.”
“We are confident that each was properly considered and addressed by Boeing, thoroughly reviewed with and approved by the FAA,” Boeing states.
An FAA spokesman declined to comment, saying that the agency will respond directly to the two legislators.
Legacy 737 design details
The shortcoming in the rudder cable design was cited in a Seattle Times story in May among a list of MAX design elements that don’t meet the latest FAA requirements.
The story listed a series of legacy design details that have been repeatedly grandfathered into the latest model each time Boeing has updated the 737, which was originally certified more than 50 years ago.
All the issues in the list were flagged by FAA safety engineers as requiring fixes before the MAX could be certified. But each was waved through after managers on the Boeing side of certification insisted that these were non-issues and managers on the FAA side agreed to let it move ahead with the requirement unaddressed.
In the case of the rudder cables, Boeing argued that the CFM-56 engine on the prior 737 model had an “excellent” service history and that it expected the new LEAP engines on the 737 MAX to have a similarly low rate of uncontained engine failures.
DeFazio and Larsen reject this argument as “nonsensical,” since it extrapolates on “the reliability of a then-unproven new engine based on the performance of a completely different older engine.”
DeFazio adds that “my staff has been told that it was virtually unprecedented for six or more FAA specialists to jointly non-concur on a single issue, highlighting the gravity of their concerns regarding the rudder cable issue.”
End runs around safety
Lightning strikes on aircraft are routine. In certain parts of the world, such as Florida and Japan, they are common.
To highlight the seriousness of the issue for the Dreamliner, DeFazio cites the example of a British Airways 787 struck by lightning two years ago shortly after it departed London’s Heathrow airport bound for India.
The plane continued its nine-hour flight but when the aircraft landed in Chennai, maintenance technicians discovered an unusual level of damage: more than 40 holes in the fuselage from the lightning strike.
The major danger from a strike is that if it were to penetrate the wing skin it could ignite the fuel vapor inside the wing, which acts as a fuel tank. When the 787 was designed as a carbon composite airframe, the FAA added a special condition requiring various design details to avoid such an explosion.
In addition to the copper foil that dissipates the energy, metal fasteners on the wing are sealed so that there is no direct metal channel all the way through from the outside to the inside of the wing skin.
That said, later the FAA also loosened a more stringent requirement established after the explosion of TWA 800 to prevent a fuel tank explosion. Bahrami, then head of the FAA’s Seattle office, led that rule change. He argued that manufacturers had found it impractical to comply.
DeFazio’s letter notes that the FAA just last month asked Boeing to perform a “risk assessment of the fuel tank explosion risk from lightning related ignition sources” on the 787 and “to determine if any corrective actions to reduce the risk of a fuel tank explosion should be required.”
However, it laments that this action is so late.
And DeFazio adds that “Boeing reportedly produced approximately 40 airplanes prior to the FAA’s approval of the design change.” He says this “suggests either willful neglect of the Federal aviation regulatory structure or an oversight system in need of desperate repair.”
His letter asks what the safety regulator is doing “ensure that manufacturers do not have an incentive to attempt end-runs around FAA technical specialists by going to senior FAA management.”
Dominic Gates: 206-464-2963 or [email protected]; on Twitter: @dominicgates.
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And DeFazio adds that “Boeing reportedly produced approximately 40 airplanes prior to the FAA’s approval of the design change.” He says this “suggests either willful neglect of the Federal aviation regulatory structure or an oversight system in need of desperate repair.”
You can google the sad tale of the fishing boat "America's Finest" (in Anacortes) to see the consequences of taking shortcuts like that when you are not an industry that owns the regulators.
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Wow guys. I'm just done with Boeing. This kind of calloused disregard for compliance with new regulations is beyond fathomable.
"give us a pass, because compliance would be HARD"
That's not acceptable for an effing Barbie doll. It should fly for a freaking aircraft? Seriously?
Step back people, take a look at the view from the peanut gallery. Boeing is beyond the point of no return, in 'good' company with PG&E, with their prioritizing profits and bonuses over safety.
Unbelievable.
"give us a pass, because compliance would be HARD"
That's not acceptable for an effing Barbie doll. It should fly for a freaking aircraft? Seriously?
Step back people, take a look at the view from the peanut gallery. Boeing is beyond the point of no return, in 'good' company with PG&E, with their prioritizing profits and bonuses over safety.
Unbelievable.
Why was it SO difficult for Boeing to design a system which endowed the aircraft with proper handling and stall protection when the Concorde designers created such a system over 50 years ago ?
On Concorde there was a high angle of attack system which retrimmed the elevons and triggered the stick shaker, signalled from the ADCs.
In addition there were TWO anti stall systems where the superstab system applied up to 8 degrees of down elevon and at speeds of 140 k and below the superstab system applied 4 degrees of down elevon.
One might think that with modern electronics and vastly more experience of FBW systems as on the 777 and 787 a better MCAS equivalent would have been a very straightforward task.
This is a basic description of the system as described in Brian Trubshaws excellent book, Concorde, the complete Inside Story, well worth a read by Boeing engineers and regulators, indeed anyone with any interest in the MCAS system and its shortcomings.
On Concorde there was a high angle of attack system which retrimmed the elevons and triggered the stick shaker, signalled from the ADCs.
In addition there were TWO anti stall systems where the superstab system applied up to 8 degrees of down elevon and at speeds of 140 k and below the superstab system applied 4 degrees of down elevon.
One might think that with modern electronics and vastly more experience of FBW systems as on the 777 and 787 a better MCAS equivalent would have been a very straightforward task.
This is a basic description of the system as described in Brian Trubshaws excellent book, Concorde, the complete Inside Story, well worth a read by Boeing engineers and regulators, indeed anyone with any interest in the MCAS system and its shortcomings.
Quite so.
Also, I don’t understand why the software issue is/was so difficult. In the USA they have all the software expertise of Silicon Valley; e.g, Apple etc. So why - if it is true - did Boeing use cheap freelance software writers, and not tap into the excellent home grown talent they have?
Also, I don’t understand why the software issue is/was so difficult. In the USA they have all the software expertise of Silicon Valley; e.g, Apple etc. So why - if it is true - did Boeing use cheap freelance software writers, and not tap into the excellent home grown talent they have?
Quite so.
Also, I don’t understand why the software issue is/was so difficult. In the USA they have all the software expertise of Silicon Valley; e.g, Apple etc. So why - if it is true - did Boeing use cheap freelance software writers, and not tap into the excellent home grown talent they have?
Also, I don’t understand why the software issue is/was so difficult. In the USA they have all the software expertise of Silicon Valley; e.g, Apple etc. So why - if it is true - did Boeing use cheap freelance software writers, and not tap into the excellent home grown talent they have?
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Quite so.
Also, I don’t understand why the software issue is/was so difficult. In the USA they have all the software expertise of Silicon Valley; e.g, Apple etc. So why - if it is true - did Boeing use cheap freelance software writers, and not tap into the excellent home grown talent they have?
Also, I don’t understand why the software issue is/was so difficult. In the USA they have all the software expertise of Silicon Valley; e.g, Apple etc. So why - if it is true - did Boeing use cheap freelance software writers, and not tap into the excellent home grown talent they have?
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Also, I don’t understand why the software issue is/was so difficult. In the USA they have all the software expertise of Silicon Valley; e.g, Apple etc. So why - if it is true - did Boeing use cheap freelance software writers, and not tap into the excellent home grown talent they have?
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Writing software is hard. Writing software which crashes securely is harder. Writing such software on a 30 year old platform with very limited hardware resources is harder. Writing such software without interfering with other critical software running for 30 years on the same platform is even harder. Writing such software in a very limited time to solve an issue not considered at the start of program is harder. Writing such software with a limited cost was probably too hard.
P.S. I tried to click on the 'like' button, but had to leave a comment instead...
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This is the pinnacle of 'too big to fail' and 'easier to ask for forgiveness than to get permission'. They rush planes to completion that are massively out of specification even withing their already grandfathered guidelines, then tell the FAA, "Well you can't expect us to have to SCRAP all these planes we made, now could you?", as the only way to achieve compliance would be a major structural redesign that is impossible to retrofit. A few shiny beads later to congressmen and FAA administrators and the necessary rubber stamps are dutifully applied and gazes redirected.
It was only by the grace of the residual decent engineering design that these massive short cuts didn't come apparent, but that 'lucky buffer' has run its course, and now the blood and guts are starting to spill. This behavior is so disgraceful it stinks to high heaven, and just goes to show the sickening greed and disregard for any decency of 'peak capitalism' of the US plutocratic type where governmental oversight has become toothless to the most shambolic, theatrical degree...
It was only by the grace of the residual decent engineering design that these massive short cuts didn't come apparent, but that 'lucky buffer' has run its course, and now the blood and guts are starting to spill. This behavior is so disgraceful it stinks to high heaven, and just goes to show the sickening greed and disregard for any decency of 'peak capitalism' of the US plutocratic type where governmental oversight has become toothless to the most shambolic, theatrical degree...
I don’t understand why the software issue is/was so difficult. In the USA they have all the software expertise of Silicon Valley; e.g, Apple etc. So why - if it is true - did Boeing use cheap freelance software writers, and not tap into the excellent home grown talent they have?
That has been the Corporate mantra in the USA and elsewhere for about 40 years now and everyone should know and understand what has been and is going on.
In brief - productivity rises every year due to human ingenuity, in the USA over 40 years ordinary workers have seen NONE of the benefit of that. ALL of the benefit has gone to a tiny proportion of the population.
You may think that is a good thing or otherwise but at least understand it.
Something else occurred in the period from the second world war until about 1980. Productivity rose similarly, however more or less everyone benefited from it.
Edited to add :-
Try Nick Hanauer's two TED talks.
Reviews of - Piketty is the author of the best-selling book Capital in the Twenty-First Century (2013), or of course read it.
In no special order :-
https://www.newyorker.com/magazine/2...rever-can-they
The Impact of American Inequality
https://www.nybooks.com/articles/201...ew-gilded-age/
https://www.ted.com/talks/nick_hanau...rd?language=en
https://www.ted.com/talks/nick_hanau...xt?language=en
None of these people are crazy.
Last edited by jimjim1; 8th Nov 2019 at 14:02.
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New questions raised on safety of both 737 MAX and 787 Dreamliner
https://www.seattletimes.com/busines...87-dreamliner/
https://www.seattletimes.com/busines...87-dreamliner/
This whole story, with all of the subplots introduced to date, has gone from very troublesome to just plain scary and creepy.
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I don't think this has been picked up yet:-
Delays in Boeing Max Return Began With Near-Crash in Simulator By Alan Levin
Delays in Boeing Max Return Began With Near-Crash in Simulator By Alan Levin
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The circle of life or how I stopped worrying about the greenbacks
Well, we knew about the rudder cable issue, but I don't remember hearing that multiple FAA folks had to be explicitly overruled or the bizarre argument that the LEAPs would probably be as trouble-free as the predecessor engines. And it's really difficult to understand how the regulator could approve deleting a conductive membrane from the wings of a mostly-composite aircraft.
This whole story, with all of the subplots introduced to date, has gone from very troublesome to just plain scary and creepy.
This whole story, with all of the subplots introduced to date, has gone from very troublesome to just plain scary and creepy.
A certification application from one of the major manufacturers lands on your desk, your arm reaches for a stamp, will it be the green or the red one? Kathunk! The production line purrs on. Your scroll through the BMW newsletter you have been eyeing for the past month, Sky Blue really is a beautiful color isn't it?
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It's difficult to understand? How about you are a manager or decision maker at the FAA, earning decent federal employee pay and benefits. The previous FAA commissioner who just 'retired' just joined the board of X aerospace company or became the head of X industry association, with an XX million dollar compensation package. Your old boss you used to work for a few years ago is now a consultant for one of the big aerospace design firms and at the last BBQ he showed up in a new Maserati and his wife wearing a big honking diamond necklace. You are a good employee and on track in the next couple years to rise through the ranks and get your old bosses job. A guy you used to work with who was kind of nerdy but an honest dude filed an official complaint against some safety issue at one of the plane manufacturer's plants some time ago. There was this whole bruhaha in the office for a while but got cleared up. You check what he's up to now on his LinkedIn, and he's now an assistant junior safety adviser at the FAA office in sunny Alert, Alaska working on tire delamination standards and testing for sport ultralight aircraft in cold weather conditions. And on Facebook he's getting all these messages wishing him good luck after his divorce.
A certification application from one of the major manufacturers lands on your desk, your arm reaches for a stamp, will it be the green or the red one? Kathunk! The production line purrs on. Your scroll through the BMW newsletter you have been eyeing for the past month, Sky Blue really is a beautiful color isn't it?
A certification application from one of the major manufacturers lands on your desk, your arm reaches for a stamp, will it be the green or the red one? Kathunk! The production line purrs on. Your scroll through the BMW newsletter you have been eyeing for the past month, Sky Blue really is a beautiful color isn't it?
Quite so.
Also, I don’t understand why the software issue is/was so difficult. In the USA they have all the software expertise of Silicon Valley; e.g, Apple etc. So why - if it is true - did Boeing use cheap freelance software writers, and not tap into the excellent home grown talent they have?
Also, I don’t understand why the software issue is/was so difficult. In the USA they have all the software expertise of Silicon Valley; e.g, Apple etc. So why - if it is true - did Boeing use cheap freelance software writers, and not tap into the excellent home grown talent they have?
But it is a shame that Boeing still use what is fundamentally a 1950’s design for the 737, which is like a MK 1 Landrover - dependable and does the job, but also very basic - and they never seemed to have the pride or willingness to really upgrade and improve their product? Yes, they added modern instrumentation and crowbarred some computers in here and there. But the cockpit is still like a cupboard, the hydraulics and systems are crude, and they didn’t ever do a properly integrated and sorted redesign, while Airbus overtook them. And Boeing have stitched themselves up now because they cannot fit large, modern fuel efficient engines under such a low wing.
I know some of the reasons were tied in with SouthWest, and pilot retraining costs etc, but as pioneers, it is a shame Boeing never truly modernised the 73.
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I don't think this has been picked up yet:-
Delays in Boeing Max Return Began With Near-Crash in Simulator By Alan Levin
Delays in Boeing Max Return Began With Near-Crash in Simulator By Alan Levin
Edit: Re-reading . . . actually, maybe it was, sort of.
From the linked article:
Changing the architecture of the jet’s twin flight computers, which drive autopilots and critical instruments, has proven far more laborious than patching the system directly involved in 737 Max crashes, said these people, who asked not to be named speaking about the issue.
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More thorough simulator testing uncovered the potential for runaway trim on the MAX, caused by the inclusion of additional relays to override the yoke cutoff switches, which were only included on the MAX to satisfy the MCAS design criteria.
This fault condition led to the requirement for dual-channel FCC monitoring on the MAX (not the NG), which has turned out more complicated and time-consuming than expected.
This story is almost a textbook example of hubris and nemesis. If MCAS had not been included on the MAX, none of this would be happening. The MAX would never have been grounded, and would be flying today with the same 'relative' level of safety as the NG series.
Like it or not Boeing is going to have to design an new narrow body.
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https://flightaware.com/live/flight/BOE1
Edited to note : The test flights all show up on flightaware.com as BOE1. There is a new extensive flight test today, Nov 7, although my original post was about the Nov 2 flight. You can see the history of the test flights on this site.
Edited to note : The test flights all show up on flightaware.com as BOE1. There is a new extensive flight test today, Nov 7, although my original post was about the Nov 2 flight. You can see the history of the test flights on this site.