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Ultimate Geek
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  Reply # 2200181 17-Mar-2019 12:59
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Dingbatt:

However, it is pretty hard to provide a differences course if the OEM doesn’t tell you about a new ‘feature’.
I wonder after 5 new handles and four new heads if it is no longer ‘Grandfather’s Axe’

 

 

IT IS SO GRANDFATHER'S AXE shout Boeing

 

...

 

Because, if it's not Grandfather's Axe, then it needs to be re-certified against modern standards, instead of being 'grandfathered' (official term!) to the old 1967 certification standards. And that would mean a lot of changes which would be very expensive and make a common type rating much more complicated.

 

There are those who believe that the FAA has been far too lax in allowing the later designs to be grandfathered, not only on the B737 but also the B747.


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Master Geek
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  Reply # 2200192 17-Mar-2019 13:30
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Dingbatt:

Airlines cover fleet differences by running a ‘differences’ course. Normally classroom work and then possibly simulator training if it’s something really complicated. In the past AirNZ has operated 737-300s with four different navigation/radio fits in a fleet of 14. And now the first A320 Neo has arrived, it is operating five sub variants of the same aircraft. I am told they have put extra checks and procedures in place to ensure pilots are aware of what sub variant they are flying before every sector.

However, it is pretty hard to provide a differences course if the OEM doesn’t tell you about a new ‘feature’.
I wonder after 5 new handles and four new heads if it is no longer ‘Grandfather’s Axe’

 

I'll quote my earlier post again, to illustrate how this actually went down, in the United States itself:

 

Tracer: To illustrate the type rating issue, check ACN 1555013 at https://titan-server.arc.nasa.gov/ASRSPublicQueryWizard/QueryWizard_Filter.aspx
This is from the USA....

I had my first flight on the Max [to] ZZZ1. We found out we were scheduled to fly the aircraft on the way to the airport in the limo. We had a little time [to] review the essentials in the car. Otherwise we would have walked onto the plane cold.

My post flight evaluation is that we lacked the knowledge to operate the aircraft in all weather and aircraft states safely. The instrumentation is completely different - My scan was degraded, slow and labored having had no experience w/ the new ND (Navigation Display) and ADI (Attitude Director Indicator) presentations/format or functions (manipulation between the screens and systems pages were not provided in training materials. If they were, I had no recollection of that material).

We were unable to navigate to systems pages and lacked the knowledge of what systems information was available to us in the different phases of flight. Our weather radar competency was inadequate to safely navigate significant weather on that dark and stormy night. These are just a few issues that were not addressed in our training.

I recommend the following to help crews w/ their introductory flight on the Max:
Email notification the day before the flight (the email should include: Links - Training Video, PSOB and QRG and all relevant updates/FAQ's)
SME (Subject Matter Expert) Observer - the role of the SME is to introduce systems navigation, display management, answer general questions and provide standardized best practices to the next generation aircraft.

Additionally, the SME will collect de-identified data to provide to the training department for analysis and dissemination to the line pilots regarding FAQs and know systems differences as well best practices in fly the new model aircraft.


 
 
 
 


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Uber Geek
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  Reply # 2200239 17-Mar-2019 14:57
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amiga500:

While I hesitate to quote a Fox news story, they got it right this time:


https://www.foxnews.com/story/aircraft-model-has-history-of-landing-gear-problems


The problems with the landing gear affected many airlines including Air NZ.   The crash near Palmerston North in 1995 was attributed to pilot distraction while the pilots were trying to deal with the landing gear, the nose gear incident landing at Blenheim more recently.  The problems with landing gear probably helped the ATR-72 become even more popular with the airlines.  Why buy the Q400 when from time to time there will be stories in the news about landing gear incidents?  


Oct. 22, 2018, © Leeham News: Bombardier has a firm backlog of 67 Q400 turboprops. ATR has a backlog of 256 through Oct. 20, according to the Airfinance Journal Fleet Tracker.


About RNP.  I wasn't making a direct comparison with the INS but pointing out that with RNP a big part of the system is the use of multiple satellites, I believe up to 14.   And if fewer satellites are available this means changes to how approaches are allowed to be conducted.   Too much reliance was placed on the INS system on the Erebus flight.    In fact I have read opinions saying it was a reckless decision by Air NZ and McMurdo to even allow flights under 16000 feet.



I don’t see how Fox News got it right at all That article focusses on stuff totally unrelated to the accident the article was about. They omitted to point out that Scandanavian Airlines was found to be at fault for substandard maintenance. Instead they decided to focus on making the aircraft the scapegoat.

The Dash 8 crash at Palmerston North happened because no one was “minding the shop”. It was no different to the 1972 Eastern Airlines flight that crashed into the Everglades due to a faulty indicator bulb. All three crew members became focussed on the faulty bulb, no one was "minding the shop", the autopilot disconnected and the aircraft descended and flew into the ground. Aircraft have faulty indicator bulbs every day but they don’t crash.

You obviously never heard about the icing problems the ATR had early on in it’s service life with loss of lives. That has been rectified now. That problem was as least as bad as the current 737 issue and certainly a lot worse than any of the Dash 8 landing gear problems. I very much doubt the Dash 8 problems had any beneficial impact on ATR sales, in fact I’d say the ATR icing issues would have outweighed Dash 8 landing problems.

The ATR is popular because accountants love it. It’s cheap to buy and operate. I don’t know anyone else that loves the ATR, it’s not a pilots aircraft and I’ve heard engineers don’t like working on it. I used to travel a lot on both the ATR and the Q300, I had no real preference for either but most of my colleagues much preferred the Dash 8 to travel on.

The sales figures you quote are meaningless. The Q400 sells into a completely different market to the ATR. The Q400 offers jet like speeds for costs more akin to turbo prop costs. It is a niche market aircraft for thin longer routes where a much bigger jet doesn’t work. The ATR is cheaper to operate and the Q400 cannot compete on shorter routes. There is a much bigger market for an aircraft like the ATR so it’s no surprise there are more orders. Apples and oranges comparison.

Your slip is showing with respect to RNP. RNP requires 5 or more satellites. The “level” of RNP doesn’t increase with more satellites. Either you have RNP capability or you don’t. These days the usual number of satellites in use at one time is 24, though it will be impossible to see all 24 at once. There are other “spare” satellites that can be brought into use as and when required.

I’ve yet to see a reputable source say that an over reliance on INS was a factor in the Erebus crash. Why do you keep focussing on this irrelevant point? If you had just said there were opinions that said is was reckless to descend below 16,000 then you would have had no argument from me.




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Uber Geek
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  Reply # 2200240 17-Mar-2019 14:58
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Sidestep:

I'd fly on a (North American or European) MAX today.


The reason they're grounded isn't because they're inherently unsafe to fly.. It's because, though the chance of another similar accident is extremely remote, if an accident - of any sort - was to happen now the cost - to Boeing - the operator - the regulators - would be so catastrophic that it's not worth that tiny risk.


The world's turned on it's head in that the FAA is no longer trusted as the arbiter of that decision. Maybe it's a sign of loss of trust in the whole US establishment, or just that organisation's top three positions are unfilled and acting Administrator Dan Elwell - who would make the decision - was once a lobbyist for airplane manufacturers.


The Lion Air crash appears to have been caused by a serious lack of communication, between the manufacturer, the airline, and it's pilots, magnified by bad engineering/design decisions, that allowed a faulty Angle of Attack sensor to cascade into the loss of an aircraft and deaths of 189 people.


A similar disagreement between the AoA sensors had caused the same issue on a previous flight, the crew (apparently recognising it as runaway trim) flipped a switch and turned the system off. The fact that the return flight, with a different crew, was then lost to the same fault points to both human and design error.


How could the AoA sensors not have been fixed? How were the new crew not warned that stick shaking and the trim indicator physically moving to a nose-down position would result? The aircraft took off with a 20 degree mismatch between the two sensors.  Seriously, how could both Angle of Attack instrumentation and an AoA disagreement warning light be 'extra cost options' on MAX's supplied to low-cost airlines? and most importantly how could an AI system be allowed to physically overpower (25 times!) the human crew's input?


With those questions unresolved, the loss of the Ethiopian flight so soon afterwards has led to public perception that the aircraft has a dangerous, unstable design.
I find that hard to believe. It may possibly be a combination of the same systems errors combined with inexperienced crew caused the second crash (I believe the co-pilot had only 200 hours) or it could be something completely different - the results of the investigation will tell what happened - and likely drive future safety and engineering decisions.


What it's sure to touch on is increasing reliance on AI rather than old fashioned human decision making and rote pilot training. It's one of the reasons I'm never going to be sitting in an autonomous vehicle with no steering wheel..


A friend came by for help with his 1998 Subaru the other day. The check engine light was flashing, there was a burning smell, smoking exhaust, and it stalled on him - first at a red light and then on the freeway offramp to our place (where he lost power assistance for his brakes and steering). The problem turned out to be a failure of one of the two engine temperature sensors, when the mismatch became large enough the ECU chose a richer mixture - injecting more and more fuel until the engine started stalling.

Maybe his self-driving 2028 Subaru, confronted with the same problem, will decide to swerve off the freeway - and into the concrete noise barrier - to save him from the risk of an engine stall. At least if it has a steering wheel - and he has enough strength - he'll have a chance to take control..



On Subaru's, 1 of the temp sensors is used by the ECU, and the other one is used by the temp gauge. With no interconnections between them. (early 90s models were definitely setup that way, haven't verified if the 98 model was also). The sensor failure would have fooled the ECU into thinking that the engine is cold. So it would have gone into cold start mode (lots of fuel enrichment) And the oxygen sensor readings are also ignored in cold start mode. Power steering is provided by a pump running from the engine, while braking assistance uses inlet manifold vacuum. Which is why the assistance stopped working when the engine stalled.

Problem - sensor failure where the ECU couldn't tell that a sensor failure had occurred. Which is what happened with the Max 8 MCAS.

The Lion Air crew who made the flight before the fatal one. Recognized a runaway trim problem, followed normal procedures to deal with it. And presumably the maintenance staff checked the trim control system, and didn't find any problems (as the problem wasn't actually with the trim control system). Since they didn't know about MCAS, they wouldn't have known to consider if MCAS was the cause of the reported trim control problem.





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  Reply # 2200245 17-Mar-2019 15:10
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amiga500:

It is all a very sorry affair for Boeing because had it not been for the two tragic crashes, just the new engine nacelles and new type of winglets would have made it a hit with passengers.  Everyone would have been saying 'Wow, first time I've been on one of the new ones' but not now..



It is very sad for Boeing, however I think the reports will show short comings in mantenance procedures and or the way the pilots handled the situation. Other pilots have handled this or similar situations sucessfully, but why not in these two instances. There will be recommendation on software/hardware changes on the aircraft too.

There have been other aircraft with similar or worse issues that have gone on to have a very good service record.

Most passengers wouldn't know if they were on a 737 - 300 / -600 / -800 or Max or a 777 -200 / -300. Significant numbers wouldn't even know if they were on a Boeing or and Airbus.

This problem will get sorted out, some airlines may improve their training standards and in a year or so most people will have forgotten.




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Uber Geek
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  Reply # 2200292 17-Mar-2019 17:11
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sbiddle:

 

amiga500:

 

 

 

And about the Air NZ B787 engine incidents.  Even if Rolls Royce did tell Air NZ it would be perfectly fine to send out the second aircraft, if Air NZ had used an abundance of caution about the advice being given by RR & the commercial context in which that advice had been given, they might have reached a different conclusion. Of course Air NZ were desperate to keep those planes flying just as RR was.   Another reason for an abundance of caution would have been the routes Air NZ fly, including the routes to South America.   It's not like the route flown by airlines from Singapore to Europe where there a multiple alternate airports for most of the journey.   If a B787 engine decides to shred itself while flying over Bulgaria or Hungary it's an entirely better situation, than having it happen halfway to Argentina!

 

 

I'm curious if you're ever actually read the TAIC reports? Because based on your comments and it would seem you haven't.

 

RR had built a model based on the 6 previous Trent 1000 failures before the 2 Air NZ ones. Both engines were well under the predicted failure points of this model, even allowing for reserve margins.

 

When the plane left for EZE the following day there was no cause for concern or alarm because the NZ99 failure cause wasn't even determined. It was only after this IPT blade failed as well that it became very clear that the RR modelling was clearly flawed.

 

Air NZ were not "desperate" to keep the planes flying, they were the ones who then voluntarily reduced their ETDO times which immediately limited 787 operations.

 

As for Q300/Q400's being bad planes I have to disagree entirely. If you'd read any incident reports you'll know their undercarriage issues have stemmed from multiple different issues, with one Air NZ one simply being because the pilots failed to actually pull hard enough on the alternate nose gear extension handle. 

 

 

Re. the RR model.   Sometimes those closest to an issue and intimately involved fail to see the reality of a situation.   For example when Jack Welch took over at GE the top executives at GE's nuclear power plant division were still presenting papers/models of future sales of nuclear power plants.  As the new President/CEO, Jack Welch told them he predicted that GE would never sell another nuclear power plant & that they had better come up with a business plan based around service and supply to existing plants.   Welch was right.

 

I would say that RR was putting too much faith in the model developed for the engine maybe because the model was based around failures in only six engines.   The RR engineers were so closely involved they had a similar lack of understanding similar to those at the top of the GE Nuclear power division.

 

Imagine if the Air NZ CEO had gone to the maintenance hangar looked at the first 787 with its shredded turbine blades, and second guessed the technical advice from RR and the Air NZ engineers, and immediately grounded the Air NZ 787s.  If this had happened everyone would be calling him a courageous genius!

 

 

 

 

 

 


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  Reply # 2200296 17-Mar-2019 17:30
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I might leave this thread alone now as I've probably drifted too far off the orginal topic although the discussions are relevant to the overall issue of identifying and fixing problems in new aircraft.

 

As for the ATR 72.  I've only had a few flights in these and none on a Q300 or Q400 although I've watched a few Youtube trip reports on the Q300/400.  I'm not sure how well they age, but based on my Queenstown to Christchurch flight on a ATR72-600 which was only about three months old, I was very impressed with the comfort and quietness at cruise.  FWIW the two excellent flight attendants seemed to be enjoying the flight as much as the passengers.   I had a window seat at the front of the ATR-72, and a window seat at the back of the A320 and noise levels seemed similar to me.

 

I've also watched an excellent Youtube about a delivery flight of an ATR 72-600 to a South American airline & was impressed with the flight deck, although I am no expert!

 

 




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  Reply # 2200314 17-Mar-2019 18:21
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some guys who seems to know what he's talking about going in to great detail (beyond my comprehension) https://qr.ae/TWRw5f





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Master Geek
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  Reply # 2200319 17-Mar-2019 18:28
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amiga500:

I might leave this thread alone now as I've probably drifted too far off the orginal topic although the discussions are relevant to the overall issue of identifying and fixing problems in new aircraft.


As for the ATR 72.  I've only had a few flights in these and none on a Q300 or Q400 although I've watched a few Youtube trip reports on the Q300/400.  I'm not sure how well they age, but based on my Queenstown to Christchurch flight on a ATR72-600 which was only about three months old, I was very impressed with the comfort and quietness at cruise.  FWIW the two excellent flight attendants seemed to be enjoying the flight as much as the passengers.   I had a window seat at the front of the ATR-72, and a window seat at the back of the A320 and noise levels seemed similar to me.


I've also watched an excellent Youtube about a delivery flight of an ATR 72-600 to a South American airline & was impressed with the flight deck, although I am no expert!


 


Q300 cabin has about twice as much rattle. IIRC the ATRs have larger overhead lockers too.

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Master Geek
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  Reply # 2202503 20-Mar-2019 17:23
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A new detail has emerged in the Lion Air accident. It was actually a third, off-duty, pilot who diagnosed the problem and saved the penultimate flight! https://www.bloomberg.com/news/articles/2019-03-19/how-an-extra-man-in-cockpit-saved-a-737-max-that-later-crashed


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  Reply # 2202618 20-Mar-2019 21:03
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Tracer:
Q300 cabin has about twice as much rattle. IIRC the ATRs have larger overhead lockers too.

 

The ATR is certainly quite and smooth but the Q300 has significantly more leg room and arguably more comfortable seats.





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  Reply # 2202873 21-Mar-2019 14:52
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Tracer:

A new detail has emerged in the Lion Air accident. It was actually a third, off-duty, pilot who diagnosed the problem and saved the penultimate flight! https://www.bloomberg.com/news/articles/2019-03-19/how-an-extra-man-in-cockpit-saved-a-737-max-that-later-crashed



This is crazy. Literally hacked the plane. But it's so sad what happened next.




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  Reply # 2202968 21-Mar-2019 18:12
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Batman:
Tracer:

 

A new detail has emerged in the Lion Air accident. It was actually a third, off-duty, pilot who diagnosed the problem and saved the penultimate flight! https://www.bloomberg.com/news/articles/2019-03-19/how-an-extra-man-in-cockpit-saved-a-737-max-that-later-crashed

 



This is crazy. Literally hacked the plane. But it's so sad what happened next.

 

I don't understand your comment. To me hacking means breaking into the code or applying a procedure that is made up on the fly.

 

My reading of that article was the Lion Air pilots couldn't remember a memory item for a failure mode and needed the dead heading pilot to remind them what to do. Not a good look.

 

All aircraft have a list of memory items for various failures. Pilots have to know these and are normally tested on these items as part of their mandatory 180 day (six monthly) simulator check flights. Once the memory items have been completed then at a suitable time the QRH (Quick Reference Handbook) is referred to, to confirm the memory items have been completed correctly and then any subsequent non memory items are carried out by following the procedures contained in the QRH.

 

It would appear to me the Lion Air crew may have been deficient as sadly I suspect will also be shown to be the case in the Ethiopian crash.

 

This doesn't absolve Boeing from any deficiencies in the MCAS,  but gives some perspective on the issue where some crews have managed to successfully land the aircraft and some haven't.





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  Reply # 2202978 21-Mar-2019 18:36
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Technofreak:

 

Batman:
Tracer:

 

A new detail has emerged in the Lion Air accident. It was actually a third, off-duty, pilot who diagnosed the problem and saved the penultimate flight! https://www.bloomberg.com/news/articles/2019-03-19/how-an-extra-man-in-cockpit-saved-a-737-max-that-later-crashed

 



This is crazy. Literally hacked the plane. But it's so sad what happened next.

 

I don't understand your comment. To me hacking means breaking into the code or applying a procedure that is made up on the fly.

 

My reading of that article was the Lion Air pilots couldn't remember a memory item for a failure mode and needed the dead heading pilot to remind them what to do. Not a good look.

 

All aircraft have a list of memory items for various failures. Pilots have to know these and are normally tested on these items as part of their mandatory 180 day (six monthly) simulator check flights. Once the memory items have been completed then at a suitable time the QRH (Quick Reference Handbook) is referred to, to confirm the memory items have been completed correctly and then any subsequent non memory items are carried out by following the procedures contained in the QRH.

 

It would appear to me the Lion Air crew may have been deficient as sadly I suspect will also be shown to be the case in the Ethiopian crash.

 

This doesn't absolve Boeing from any deficiencies in the MCAS,  but gives some perspective on the issue where some crews have managed to successfully land the aircraft and some haven't.

 

 

Personally, common courtesy, I'd suggest you wait for the facts to emerge before making assumptions and trashing the pilots.

 

 

 

 


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  Reply # 2203066 21-Mar-2019 20:47
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dafman

 

Yes, I may be making some assumptions but I also speak with a little bit of knowledge on the subject. I'd like to think if I was faced with a similar situation I'd know how to handle it. I am a pilot myself and I don't like casting aspersions on fellow pilots but evidence so far shows other pilots have dealt with this problem successfully by following the correct procedures. 

 

One question that has to be asked is why did these two crews not manage to do so? That shows there is a deficiency somewhere. That can mean a deficiency in training which is not a direct reflection on the individual pilots. So was it lack of training or something else?





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