Ethiopian airliner down in Africa
Join Date: Nov 2007
Location: dublin
Posts: 2
Likes: 0
Received 0 Likes
on
0 Posts
Gums says 'cutting accident crew some slack". So does everyone I think. If they made an error and we have no idea if they did, it would not be their fault but poor training. I have never met or heard of a pilot who sets out to do a bad job or kill himself. Other than the Pyrenees incident of co
course.
There seems to be a bit of a muddle about AoA sensors and Airpspeed disagree. They are not necessarily connected in any way.
AoA detects a stall by measuring the angle of attack with two sensors, one each side. Measuring the angle of airflow.
Speed is measured by sensing air pressure in a tube facing forwards (pitot)and converting that into Indicated Airpspeed. Not the same as real speed.
GPS measures real speed and is almost never wrong.
Say you have blocked pitot tubes as per aF 447, the AoA still works and stall warning still works.
Say you have frozen AoA vanes so that they are not able to detect stall, or incorrectly detect a stall (as is suggested in these Max incidents) then the Airspeed should still work.
Another scenario is that one airspeed is faulty, but the other two work - there are three airspeed indicators. That one is easy since you go for the two that agree. Backed up with GPS.
And in all these cases GPS will still work.
So the changes of losing AoA information AND Airspeed information at the same time are pretty remote.
This is just for information since there seems to be a misunderstanding about the functions of the various systems here.
There is one last way of determining speed. Pitch and power. 6 degrees of pitch and 60% N1 power will fly straight and level and at a safe speed NO MATTER WHAT ANY OF THESE OTHER SYSTEMS ARE SAYING. [True for lower levels]
The point is I suppose that this is a very complicated area but we can also overcomplicate it.
Yanrair
course.
There seems to be a bit of a muddle about AoA sensors and Airpspeed disagree. They are not necessarily connected in any way.
AoA detects a stall by measuring the angle of attack with two sensors, one each side. Measuring the angle of airflow.
Speed is measured by sensing air pressure in a tube facing forwards (pitot)and converting that into Indicated Airpspeed. Not the same as real speed.
GPS measures real speed and is almost never wrong.
Say you have blocked pitot tubes as per aF 447, the AoA still works and stall warning still works.
Say you have frozen AoA vanes so that they are not able to detect stall, or incorrectly detect a stall (as is suggested in these Max incidents) then the Airspeed should still work.
Another scenario is that one airspeed is faulty, but the other two work - there are three airspeed indicators. That one is easy since you go for the two that agree. Backed up with GPS.
And in all these cases GPS will still work.
So the changes of losing AoA information AND Airspeed information at the same time are pretty remote.
This is just for information since there seems to be a misunderstanding about the functions of the various systems here.
There is one last way of determining speed. Pitch and power. 6 degrees of pitch and 60% N1 power will fly straight and level and at a safe speed NO MATTER WHAT ANY OF THESE OTHER SYSTEMS ARE SAYING. [True for lower levels]
The point is I suppose that this is a very complicated area but we can also overcomplicate it.
Yanrair
Join Date: Jul 2014
Location: Germany
Posts: 344
Likes: 0
Received 0 Likes
on
0 Posts
Another scenario is that one airspeed is faulty, but the other two work - there are three airspeed indicators. That one is easy since you go for the two that agree. Backed up with GPS.
And in all these cases GPS will still work.
So the changes of losing AoA information AND Airspeed information at the same time are pretty remote.
This is just for information since there seems to be a misunderstanding about the functions of the various systems here.
And in all these cases GPS will still work.
So the changes of losing AoA information AND Airspeed information at the same time are pretty remote.
This is just for information since there seems to be a misunderstanding about the functions of the various systems here.
(And at 7000 ft you also have to take air density into account, which makes ground speed even harder to use)
As has been stated before, the airspeed and altitude are corrected for AoA.
That is because the static ports and pitot probes are affected by the airflow around the airframe.
At different angles of attack that flow is different, thus there is a relatively small correction made.
Just have a look at the differing airspeed/altitude introduced by the AoA misreading in the Lion Air report FDR graphs:
https://www.flightradar24.com/blog/w...ary-Report.pdf
Last edited by wiedehopf; 20th Mar 2019 at 20:35.
Join Date: Oct 2007
Location: Alameda, CA, USA
Posts: 16
Likes: 0
Received 0 Likes
on
0 Posts
Boeing's mission is the same as any other publicly listed company - to maximise profits for the shareholders and to act in their best interests. To do otherwise would probably be a dereliction of the directors legal responsibilities. It does this by designing and manufacturing equipment to the highest standards but that is not its mission, it's the means to the end. I do not mean to denigrate Boeing's equipment and staff and all their efforts which I personally admire hugely. But it's the truth.
https://www.washingtonpost.com/news/...=.7882f492e5aa
Join Date: Aug 2018
Location: Madrid
Posts: 21
Likes: 0
Received 0 Likes
on
0 Posts
Doesn’t Boeing basically admit negligence and responsibility for the crash with the original design?
The whole “it was safe but now it’s safer” spin is like mcdonalds lowering the temperature of coffee “just to make it even safer and more full bodied now”. Remember, mcdonalds had to pay 2.7M just for burns - to a single person.
Evidently FAA and Boeing both agreed these were required changes to MCAS logic from what they could learn from LionAir. Why the type was not grounded then and instead they let the fleet fly while developing the fix which is now being required to have them airworthy again is very questionable...
Join Date: Feb 2009
Location: Seattle
Posts: 379
Likes: 0
Received 0 Likes
on
0 Posts
FCeng84 - Excellent comments on the ‘bigger picture’ of the problem. You refer to “the elephant in the room”, this does not only apply to MCAS. Some years ago when I was an aviation safety assessor, shortly after the loss of AF447, it became clear to me the premise that ADU TAS output is not a ‘safety critical’ parameter was a badly flawed concept. The approach of suppliers and the aviation authorities was that TAS was only ‘advisory information’ and that incorrect data would be handled by ‘good airmanship’. It is ‘obvious’ from AF447 and three other incidents I am aware of, the probability that pilots can always safely deal with bad Air Data is not high enough to mitigate the ADS to be not a safety critical system. Sadly this elephant is still hidden away, for now.
The same flawed argument now seems to being applied to AoA with MCAS. I am only aware of three cases of the MCAS not working correctly, in only one case did the crew manage to safely deal with the situation. The real hard evidence suggests that a significant proportion of pilots (somewhere between 10% and 90%) would not be able to cope. From what I understand about MCAS from the Pprune posts, I would expect this probability of pilots failing to cope would need to be of the order of 0.1% (or lower) in order for the MCAS to be considered as not safety critical. IHO, only a basic understanding of Human Factors is needed to show that the MCAS safety assessment is fundamentally flawed. This is the elephant in the room, Boeing might perhaps try to hide it with a software patch, but it will still be there.
The software patch looks inadequate to me for the following reasons:-
A) Quote from https://www.seattletimes.com/busines...ion-air-crash/
“According to a detailed FAA briefing to legislators, Boeing will change the MCAS software to give the system input from both angle-of-attack sensors. It will also limit how much MCAS can move the horizontal tail in response to an erroneous signal. And when activated, the system will kick in only for one cycle, rather than multiple times.”
I find this quite disturbing:-
i) They seem to have ‘defined’ the software patch before they even know the cause.
ii) How does having both inputs help if one of them is ‘erroneous, but believable’?
iii) Presumably the software would have be set to be cautious and use the higher (potentially wrong) value?
iv) MCAS was originally designed at its current limits in order to counteract a known problem. Presumably lowering the limits mean that more ‘real’ problems will not now be safely dealt with.
B) There may well be failure modes other than the AoA vane that need to be considered. From https://leehamnews.com/2018/11/07/bo...-air-accident/ the Alpha Vanes input to the ADIRUs, presumably there they are at least A to D converted. Are the (non-safety critical) ADIRUs a potential source of failures?
C) From The Seattle Times report, the MCAS was not considered to be a Level 1 safety critical system, so presumably the software was not designed, developed and tested to Level 1 standards. In which case, a software failure within the MCAS has to be considered as a feasible cause of the MCAS’s undesirable behaviour.
Considering your points A to E on the future of aviation safety: I fear the aviation industry is approaching a ‘perfect storm’ dilemma:
a) aircraft are becoming more complex, even Boeing consider that “average” pilots cannot cope with the workload of extra information about MCAS
b) air traffic is increasing and new aircraft designs are ‘down-sizing’ as smaller aircraft are more cost effective; this means many more new, inexperienced, pilots will be needed
c) it is not possible to train pilots such that they all become ‘super Sulleys’.
My conclusions are:-
a) systems must no longer use human intervention as part of their safety case; we are too unpredictable.
b) safety critical systems must get smarter; garbage in, garbage out is not an option, neither is giving up and disconnecting.
The same flawed argument now seems to being applied to AoA with MCAS. I am only aware of three cases of the MCAS not working correctly, in only one case did the crew manage to safely deal with the situation. The real hard evidence suggests that a significant proportion of pilots (somewhere between 10% and 90%) would not be able to cope. From what I understand about MCAS from the Pprune posts, I would expect this probability of pilots failing to cope would need to be of the order of 0.1% (or lower) in order for the MCAS to be considered as not safety critical. IHO, only a basic understanding of Human Factors is needed to show that the MCAS safety assessment is fundamentally flawed. This is the elephant in the room, Boeing might perhaps try to hide it with a software patch, but it will still be there.
The software patch looks inadequate to me for the following reasons:-
A) Quote from https://www.seattletimes.com/busines...ion-air-crash/
“According to a detailed FAA briefing to legislators, Boeing will change the MCAS software to give the system input from both angle-of-attack sensors. It will also limit how much MCAS can move the horizontal tail in response to an erroneous signal. And when activated, the system will kick in only for one cycle, rather than multiple times.”
I find this quite disturbing:-
i) They seem to have ‘defined’ the software patch before they even know the cause.
ii) How does having both inputs help if one of them is ‘erroneous, but believable’?
iii) Presumably the software would have be set to be cautious and use the higher (potentially wrong) value?
iv) MCAS was originally designed at its current limits in order to counteract a known problem. Presumably lowering the limits mean that more ‘real’ problems will not now be safely dealt with.
B) There may well be failure modes other than the AoA vane that need to be considered. From https://leehamnews.com/2018/11/07/bo...-air-accident/ the Alpha Vanes input to the ADIRUs, presumably there they are at least A to D converted. Are the (non-safety critical) ADIRUs a potential source of failures?
C) From The Seattle Times report, the MCAS was not considered to be a Level 1 safety critical system, so presumably the software was not designed, developed and tested to Level 1 standards. In which case, a software failure within the MCAS has to be considered as a feasible cause of the MCAS’s undesirable behaviour.
Considering your points A to E on the future of aviation safety: I fear the aviation industry is approaching a ‘perfect storm’ dilemma:
a) aircraft are becoming more complex, even Boeing consider that “average” pilots cannot cope with the workload of extra information about MCAS
b) air traffic is increasing and new aircraft designs are ‘down-sizing’ as smaller aircraft are more cost effective; this means many more new, inexperienced, pilots will be needed
c) it is not possible to train pilots such that they all become ‘super Sulleys’.
My conclusions are:-
a) systems must no longer use human intervention as part of their safety case; we are too unpredictable.
b) safety critical systems must get smarter; garbage in, garbage out is not an option, neither is giving up and disconnecting.
A i) The update in work by Boeing is in response to the Lion Air accident, not the Ethiopian accident. Hopefully we will know more about the Ethiopian accident soon and only then will it be possible to determine if this same update would have helped lead to a better outcome in Ethiopia.
A ii) It seems that the proposed update will disable MCAS if the two AOA vanes do not track each other sufficiently. The severity of the degradation in handling qualities without MCAS must be minor enough to allow for this reduction in MCAS availability. Boeing must be assuming some probability for an AOA sensor failure and then showing that it is acceptable to turn MCAS off twice as often as a failure of either AOA sensor would lead to MCAS shut down.
A iii) No MCAS when AOA vanes do not track. See A ii above.
A iv) I doubt that we will find that the MCAS update reduces the size of a single increment of MCAS stabilizer motion. I can't imagine that Boeing would have given this function any more authority than absolutely needed to meet FARs and thus there is probably no room to reduce its single increment authority.
C) MCAS is implemented within the FCC within the same software that controls other automatic stabilizer control functions such as offload when A/P is engaged and STS. This code already required to be designed to high standards.
Conclusion a) We may need to rely less on critical crew action, but there must be some base level that can be counted upon. I suggest at least:
- RTO for engine out below V1
- Pull for takeoff somewhere near Vr
- Gear and flap management and coordination with associated speeds throughout flight
- Comply with ATC guidance
- Ability to navigate to destination
- Ability to capture and follow glideslope and localizer to runway and command landing flare
- Recognize unstable approach and execute go-around
- Sorry for the length of this list. My point is that there are many pilot actions we count on to maintain safe operation
Conclusion b) I fully agree and suggest adding that if the inputs are garbage the system should be robust enough to maintain safety.
Join Date: Jul 2013
Location: Southern Maryland
Age: 56
Posts: 17
Likes: 0
Received 0 Likes
on
0 Posts
AoA detects a stall by measuring the angle of attack with two sensors, one each side. Measuring the angle of airflow.
Speed is measured by sensing air pressure in a tube facing forwards (pitot)and converting that into Indicated Airpspeed. Not the same as real speed.
GPS measures real speed and is almost never wrong.
Say you have blocked pitot tubes as per aF 447, the AoA still works and stall warning still works.
Say you have frozen AoA vanes so that they are not able to detect stall, or incorrectly detect a stall (as is suggested in these Max incidents) then the Airspeed should still work.
Another scenario is that one airspeed is faulty, but the other two work - there are three airspeed indicators. That one is easy since you go for the two that agree. Backed up with GPS.
Speed is measured by sensing air pressure in a tube facing forwards (pitot)and converting that into Indicated Airpspeed. Not the same as real speed.
GPS measures real speed and is almost never wrong.
Say you have blocked pitot tubes as per aF 447, the AoA still works and stall warning still works.
Say you have frozen AoA vanes so that they are not able to detect stall, or incorrectly detect a stall (as is suggested in these Max incidents) then the Airspeed should still work.
Another scenario is that one airspeed is faulty, but the other two work - there are three airspeed indicators. That one is easy since you go for the two that agree. Backed up with GPS.
AOA sensors are not always duplicated. Yes, on the 737 they are, as with nearly all commercial aircraft, but that's not a universal fact.
Pitot *AND* static pressures are both required for measuring airspeed. In fact, airspeed is a function of the difference between the two.
Pitot/static speed as shown to the pilot on his airspeed indicator *IS* a real speed. Yes, it's got some assumptions wrapped in it - specifically, standard day pressure - but it's far more useful to a pilot than GPS speed. The airplane cares not a whit how fast over the ground it's moving; it flies according to the pressure field around it, which is a function of altitude and temperature and humidity.
GPS speed is not "almost never wrong". Its accuracy is strongly dependent on the relative position of the satellites. Yes, it's fairly reliable. But onboard air data sensors are far more predictable and reliable.
GPS speed by itself is fairly useless unless you know (with some certainty) the speed and direction of the wind and the airplane altitude and the ambient temperature and humidity. To get back to a useful airspeed, you need quite a bit of additional data. In fact, calibrating airplane Pitot/static systems using GPS data is astoundingly difficult. I should know - I developed several test methods for doing exactly that.
Some airplanes do use Pitot/static data for stall warning. In fact, most commercial airliners (like the 737) show a "zipper" of minimum speed which is also used to activate stall prevention systems; this is computed directly from Pitot/static data.
AOA data is used to correct Pitot/static errors. An incorrect AOA can definitely screw up the indications of altitude and airspeed, and cause changes in automation that depends on those values.
Join Date: Dec 2018
Location: Seattle
Posts: 3
Likes: 0
Received 0 Likes
on
0 Posts
No links from me yet, but a snip from a Seattle Times story posted this afternoon (partial url: :...http://www.seattletimes.com/business...oeing-737-max/)
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... citing an unnamed source.
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... citing an unnamed source.
Join Date: Nov 2015
Location: Hinckley, OH
Posts: 3
Likes: 0
Received 0 Likes
on
0 Posts
Doesn’t Boeing basically admit negligence and responsibility for the crash with the original design?
The whole “it was safe but now it’s safer” spin is like mcdonalds lowering the temperature of coffee “just to make it even safer and more full bodied now”. Remember, mcdonalds had to pay 2.7M just for burns - to a single person.
Last edited by Piper J3; 21st Mar 2019 at 01:13.
Join Date: Sep 2017
Location: Europe
Posts: 1,674
Likes: 0
Received 0 Likes
on
0 Posts
Boeing's mission is the same as any other publicly listed company - to maximise profits for the shareholders and to act in their best interests. To do otherwise would probably be a dereliction of the directors legal responsibilities. It does this by designing and manufacturing equipment to the highest standards but that is not its mission, it's the means to the end. I do not mean to denigrate Boeing's equipment and staff and all their efforts which I personally admire hugely. But it's the truth.
The board of any public company, is in the statute, required to act in good faith and the best interest of the company.
Pursuit of profit is not necessarily in the long term interests of the company owners.
For management may pursue all sorts of profit maximising activity which could include simply sell off all the assets. This may maximise 'profit' in the short term, but may damage the company and the interests of the owners, both current and future.
The role of the board is governance. That is how it is framed in the statute in the United states, the UK and the antipodes.
Directors have at their disposal both internal and external resources and are as demonstrated by case law, required to satisfy themselves by conducting any investigation into a matter they deem appropriate.
Eye pleasing stock prices satisfy management, and you can bet the CEO of Boeing's statement have careful consideration of share market impact. After all personal remuneration is at stake.
Weasel word statements carefully vetted by in-house legal and PR contain nothing admissible, no admission of fault, wrong doing or responsibility.
They are as lightweight as the paper on which they are written.
The directors of Boeing will be looking closely at any personal exposure.
Were one to look at the statute in Germany, directors are far more accountable for impact on among other things customers.
Join Date: Sep 2008
Location: Australia
Posts: 41
Likes: 0
Received 0 Likes
on
0 Posts
GPS is irrelevant to this thread.
GPS position is irrelevant to this thread. Even if the speed of the aircraft relative to the Earth was relevant, the 737 does not use GPS to display ground speed. It uses the calculated FMC position, which is derived from the IRS position, the triangulated DME position, and the GPS position via a complex formula. At times, the GPS input to the FMC may be ignored altogether. And in fact, GPS is not even required for non-EDTO (Extended over water) 737 operations.
Join Date: Jun 2009
Location: NNW of Antipodes
Age: 81
Posts: 1,330
Received 0 Likes
on
0 Posts
My thoughts about MCAS as a hardware designer:
1. Aircraft are nonlinear/unstable systems that can only be stabilized by control laws in a small (linear perturbations) part of the parameter space. A deep stall is an example of non-linearity.
2. Complexity explodes exponentially with state (autopilot mode, AOA vane failure detected etc.), an important design goal is to reduce state. State includes any if... then... in software.
When software initiates a state change on its own (autopilot switches off, systems disabled because of a broken sensor, stall recovery deployed) this should be announced to the pilot by aural warning. A pilot should always know exactly what the control state of the aircraft is, 'what is it doing now?' is not a good thing to wonder about up in the air.
3. There is unavoidable state that relates to the physics of flying: flaps, trim, gear = configuration. If automation is allowed to mess with configuration there must be cutouts and self-checks (cross checks against other sensors, stick position, whether data is consistent) to prevent instability.
4. MCAS has a very specific control function in a specific part of the flight envelope. It is easy to cross check with other sensors whether this part of the flight envelope is entered and how large a control input is required.
It puzzles me that, at complete odds with this, MCAS was given an integrating control function without bounds on a crucial flight control surface. Without data validity check. Without aural deployment warning. Without aural and visual AoA disagree warning. Without control input cross check. Without ADIRU cross check.
With safety critical subsystems there should always be at least 2 barriers before handing things over to a human as the last line of defense to prevent an incident.
1. Aircraft are nonlinear/unstable systems that can only be stabilized by control laws in a small (linear perturbations) part of the parameter space. A deep stall is an example of non-linearity.
2. Complexity explodes exponentially with state (autopilot mode, AOA vane failure detected etc.), an important design goal is to reduce state. State includes any if... then... in software.
When software initiates a state change on its own (autopilot switches off, systems disabled because of a broken sensor, stall recovery deployed) this should be announced to the pilot by aural warning. A pilot should always know exactly what the control state of the aircraft is, 'what is it doing now?' is not a good thing to wonder about up in the air.
3. There is unavoidable state that relates to the physics of flying: flaps, trim, gear = configuration. If automation is allowed to mess with configuration there must be cutouts and self-checks (cross checks against other sensors, stick position, whether data is consistent) to prevent instability.
4. MCAS has a very specific control function in a specific part of the flight envelope. It is easy to cross check with other sensors whether this part of the flight envelope is entered and how large a control input is required.
It puzzles me that, at complete odds with this, MCAS was given an integrating control function without bounds on a crucial flight control surface. Without data validity check. Without aural deployment warning. Without aural and visual AoA disagree warning. Without control input cross check. Without ADIRU cross check.
With safety critical subsystems there should always be at least 2 barriers before handing things over to a human as the last line of defense to prevent an incident.
Therein lies the problem, as Boeing have hung MCAS on the tail of the STS, which has for many years operated quietly in the background to effectively neutralize long period elevator demand, and thereby providing the full range of elevator control when required on demand. Its the extra lift generated by the engine nacelles, now further forward and higher than those on the NG, that needed to be neutralized to maintain the correct feedback forces on the control column in high AoA situations.
As described by StuntPilot, MCAS is a reconfiguration sub-system relying on non validated air data, and steps across the safety critical barrier in an insidious way.
SkyGod
Join Date: Aug 2000
Location: Palm Coast, Florida, USA
Age: 67
Posts: 1,541
Likes: 0
Received 10 Likes
on
1 Post
Maybe. Maybe he was one of the Yeager, Doolittle or Lindbergh clones we have here or like Luke?
Been doing it in various Boeing simulators for 30 years and once in real life, pretty basic stuff, really..
We still don’t know what happened in Etiophia, it has been quiet after they got the FDR and CVR readouts. Could have been a bunch of things other than faulty AoA or MCAS.
If it was a runaway stab however, you don’t have to be Chuck Yeager to stop it cold.
Join Date: Nov 2015
Location: Here
Posts: 318
Likes: 0
Received 0 Likes
on
0 Posts
The statutory duties of directors are not what you state as a 'mission' and maximise profits.
The board of any public company, is in the statute, required to act in good faith and the best interest of the company.
Pursuit of profit is not necessarily in the long term interests of the company owners.
For management may pursue all sorts of profit maximising activity which could include simply sell off all the assets. This may maximise 'profit' in the short term, but may damage the company and the interests of the owners, both current and future.
The role of the board is governance. That is how it is framed in the statute in the United states, the UK and the antipodes.
Directors have at their disposal both internal and external resources and are as demonstrated by case law, required to satisfy themselves by conducting any investigation into a matter they deem appropriate.
Eye pleasing stock prices satisfy management, and you can bet the CEO of Boeing's statement have careful consideration of share market impact. After all personal remuneration is at stake.
Weasel word statements carefully vetted by in-house legal and PR contain nothing admissible, no admission of fault, wrong doing or responsibility.
They are as lightweight as the paper on which they are written.
The directors of Boeing will be looking closely at any personal exposure.
Were one to look at the statute in Germany, directors are far more accountable for impact on among other things customers.
The board of any public company, is in the statute, required to act in good faith and the best interest of the company.
Pursuit of profit is not necessarily in the long term interests of the company owners.
For management may pursue all sorts of profit maximising activity which could include simply sell off all the assets. This may maximise 'profit' in the short term, but may damage the company and the interests of the owners, both current and future.
The role of the board is governance. That is how it is framed in the statute in the United states, the UK and the antipodes.
Directors have at their disposal both internal and external resources and are as demonstrated by case law, required to satisfy themselves by conducting any investigation into a matter they deem appropriate.
Eye pleasing stock prices satisfy management, and you can bet the CEO of Boeing's statement have careful consideration of share market impact. After all personal remuneration is at stake.
Weasel word statements carefully vetted by in-house legal and PR contain nothing admissible, no admission of fault, wrong doing or responsibility.
They are as lightweight as the paper on which they are written.
The directors of Boeing will be looking closely at any personal exposure.
Were one to look at the statute in Germany, directors are far more accountable for impact on among other things customers.
https://www.franciswilksandjones.co....uciary_duties/
“Directors of any company in the UK are separate from the business owners, who are the Shareholders, and have a duty to manage the company (or companies), over which they are appointed, solely in the interest of Shareholders.”
I don’t think we are too much at odds with one another on this.
Join Date: Jul 2014
Location: Harbour Master Place
Posts: 662
Likes: 0
Received 0 Likes
on
0 Posts
The bigger picture here is the (lack of) training. Training is perceived as expensive by operators, to be minimised by the accountants and finance types. The reason we have the MAX and not the 7x7 narrowbody is because of (non)-training. Training has progressively been hacked back to the absolute bare minimum to pass the course. There are less and less descriptions in the manual of systems operations, limitations have been reduced to the colour coding on the instruments. In short, commercial pressures (perceived or real) have reduced pilots to mere SOP system operators. From the accountants perspective, all problems have been solved by the aircraft manufactures, and grudging concede we just need the absolute lowest level carbon based AI automons to read the checklist and follow SOP, to the letter if something goes wrong.
To accountants, flying aeroplanes is a "settled science", and therefore training and employment conditions are the subject to round after round of continuous cuts and we still have a "NEW" 1967 aircraft rolling off the production line with all the human factor issues baked in from another era extending well into the future. They have failed to accept the QRH introduction that states the assumption behind the checklist is that only one thing will go wrong at a time, and do not consider multiple failures.
AF447, Air Asia 8501 TransAsia Airways Flight 235 as well as a string of Adam Air incidents & accidents all have their genesis in the minimum training philosophy. Unfortunately, the trend is likely to continue until the industry wakes up to the fact that cutting training to the bone is NOT a competitive advantage.
To accountants, flying aeroplanes is a "settled science", and therefore training and employment conditions are the subject to round after round of continuous cuts and we still have a "NEW" 1967 aircraft rolling off the production line with all the human factor issues baked in from another era extending well into the future. They have failed to accept the QRH introduction that states the assumption behind the checklist is that only one thing will go wrong at a time, and do not consider multiple failures.
AF447, Air Asia 8501 TransAsia Airways Flight 235 as well as a string of Adam Air incidents & accidents all have their genesis in the minimum training philosophy. Unfortunately, the trend is likely to continue until the industry wakes up to the fact that cutting training to the bone is NOT a competitive advantage.
Join Date: Nov 2007
Location: dublin
Posts: 2
Likes: 0
Received 0 Likes
on
0 Posts
Gordon speaks a lot of sense and has it right and well balanced.
Yanrair
Join Date: May 2016
Location: Nantes
Posts: 63
Likes: 0
Received 0 Likes
on
0 Posts
Suppose MCAS becomes unavailable during flight e.g. due to Stab trim deactivation. The MAX’s flight characteristics in approach to stall scenarios proved not certifiable without MCAS as a fix. I’d like to ask the ones in the know (FcEng and others) how critical the loss of MCAS in flight would be in real life. For example, encountering a flight upset with approach to stall, how easily can this be recovered without MCAS? How was the risk of such an event assessed? Was it demonstrated in test flights? Why was it determined there would be no need to train flight crews on the simulator for the changed handling outside the certification parameters?
In a previous post I assumed such a scenario to be critcal, but perhaps it isn’t? Thanking you in advance for shedding light on this issue.
In a previous post I assumed such a scenario to be critcal, but perhaps it isn’t? Thanking you in advance for shedding light on this issue.
Not only MCAS would be missing, also STS and electric trim, everything would have to be done manually by the trim wheel and a good amount of sweat...
Last edited by deltafox44; 20th Mar 2019 at 22:52. Reason: clarity
Join Date: May 2016
Location: Nantes
Posts: 63
Likes: 0
Received 0 Likes
on
0 Posts
Likewise, when I read their statement, "to make a safe airplane safer" I also raised the eyebrow.
Evidently FAA and Boeing both agreed these were required changes to MCAS logic from what they could learn from LionAir. Why the type was not grounded then and instead they let the fleet fly while developing the fix which is now being required to have them airworthy again is very questionable...
Evidently FAA and Boeing both agreed these were required changes to MCAS logic from what they could learn from LionAir. Why the type was not grounded then and instead they let the fleet fly while developing the fix which is now being required to have them airworthy again is very questionable...
"to make a safe airplane safer" is just a Coué-method equivalent of "to make a dangerous airplane a little less dangerous"
Or an aeronautical equivalent of washing powder advertisement "to wash whiter than white". If it's whiter now, it was not white before, it was grey
Join Date: Jul 2013
Location: Norway
Age: 57
Posts: 140
Likes: 0
Received 0 Likes
on
0 Posts
VicMel - I really appreciate your thoughtful response. I sense that overall you and I are on the same page. Please allow me to provide a few inputs on your points:
A i) The update in work by Boeing is in response to the Lion Air accident, not the Ethiopian accident. Hopefully we will know more about the Ethiopian accident soon and only then will it be possible to determine if this same update would have helped lead to a better outcome in Ethiopia.
A ii) It seems that the proposed update will disable MCAS if the two AOA vanes do not track each other sufficiently. The severity of the degradation in handling qualities without MCAS must be minor enough to allow for this reduction in MCAS availability. Boeing must be assuming some probability for an AOA sensor failure and then showing that it is acceptable to turn MCAS off twice as often as a failure of either AOA sensor would lead to MCAS shut down.
A iii) No MCAS when AOA vanes do not track. See A ii above.
A iv) I doubt that we will find that the MCAS update reduces the size of a single increment of MCAS stabilizer motion. I can't imagine that Boeing would have given this function any more authority than absolutely needed to meet FARs and thus there is probably no room to reduce its single increment authority.
C) MCAS is implemented within the FCC within the same software that controls other automatic stabilizer control functions such as offload when A/P is engaged and STS. This code already required to be designed to high standards.
Conclusion a) We may need to rely less on critical crew action, but there must be some base level that can be counted upon. I suggest at least:
- RTO for engine out below V1
- Pull for takeoff somewhere near Vr
- Gear and flap management and coordination with associated speeds throughout flight
- Comply with ATC guidance
- Ability to navigate to destination
- Ability to capture and follow glideslope and localizer to runway and command landing flare
- Recognize unstable approach and execute go-around
- Sorry for the length of this list. My point is that there are many pilot actions we count on to maintain safe operation
Conclusion b) I fully agree and suggest adding that if the inputs are garbage the system should be robust enough to maintain safety.
A i) The update in work by Boeing is in response to the Lion Air accident, not the Ethiopian accident. Hopefully we will know more about the Ethiopian accident soon and only then will it be possible to determine if this same update would have helped lead to a better outcome in Ethiopia.
A ii) It seems that the proposed update will disable MCAS if the two AOA vanes do not track each other sufficiently. The severity of the degradation in handling qualities without MCAS must be minor enough to allow for this reduction in MCAS availability. Boeing must be assuming some probability for an AOA sensor failure and then showing that it is acceptable to turn MCAS off twice as often as a failure of either AOA sensor would lead to MCAS shut down.
A iii) No MCAS when AOA vanes do not track. See A ii above.
A iv) I doubt that we will find that the MCAS update reduces the size of a single increment of MCAS stabilizer motion. I can't imagine that Boeing would have given this function any more authority than absolutely needed to meet FARs and thus there is probably no room to reduce its single increment authority.
C) MCAS is implemented within the FCC within the same software that controls other automatic stabilizer control functions such as offload when A/P is engaged and STS. This code already required to be designed to high standards.
Conclusion a) We may need to rely less on critical crew action, but there must be some base level that can be counted upon. I suggest at least:
- RTO for engine out below V1
- Pull for takeoff somewhere near Vr
- Gear and flap management and coordination with associated speeds throughout flight
- Comply with ATC guidance
- Ability to navigate to destination
- Ability to capture and follow glideslope and localizer to runway and command landing flare
- Recognize unstable approach and execute go-around
- Sorry for the length of this list. My point is that there are many pilot actions we count on to maintain safe operation
Conclusion b) I fully agree and suggest adding that if the inputs are garbage the system should be robust enough to maintain safety.
Thanks!
https://www.reuters.com/article/us-e...-idUSKCN1R11AK
March 20, 2019 / 4:39 AM / Updated 7 minutes ago
March 20, 2019 / 4:39 AM / Updated 7 minutes ago
Boeing, FAA officials called to testify in U.S. Senate on 737 MAX plane crashes
Maggie Fick, Cindy Silviana, David Shepardson
ADDIS ABABA/JAKARTA/WASHINGTON (Reuters)
Boeing Co faced growing pressure in Washington on Wednesday with U.S. lawmakers calling for executives to testify about two crashed 737 MAX jets even as the world’s biggest planemaker works to overcome obstacles to returning the grounded fleet to the skies.
ADDIS ABABA/JAKARTA/WASHINGTON (Reuters)
Boeing Co faced growing pressure in Washington on Wednesday with U.S. lawmakers calling for executives to testify about two crashed 737 MAX jets even as the world’s biggest planemaker works to overcome obstacles to returning the grounded fleet to the skies.
