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Boeing 737-8 Max


St Chalet

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Given the recent crash and subsequent grounding, would value our esteemed experts views on whether these two crashes are related?

 

Nobody can say until both accidents have been properly investigated but the similarities are concerning enough to take all precautions. The planes are new enough for this not to be a maintenance issue and sensors/instruments aren't the kind of thing which wear out anyway.

 

I'd GUESS at this being some sort of software issue but it's nothing more than a guess.

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Could well be just coincidence if reports of smoke coming from the rear of the Ethiopian plane before it crashed are accurate. Who knows though.

 

Why would smoke be coming from the rear of any plane though, the engines are towards the front. If there really was smoke and a strange noise then it wouldn't at all surprise me if it's a terrorist jobby with all those diplomats on board. Then again sitings of MH370 were about everywhere.

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Could well be just coincidence if reports of smoke coming from the rear of the Ethiopian plane before it crashed are accurate. Who knows though.

 

There are almost always reports of smoke from eye witnesses which usually turn out to be something else. Areas of low pressure around the air frame can lead to water vapour forming, especially in areas of high humidity which I'd guess this might be.

 

This photo sort of illustrates it, with the vapour forming above the wings as the aircraft performs a tight-ish turn.

371bd93a6721531785e2bf898c29a05b.jpg

 

If the aircraft is falling at some unusual attitude then it's not impossible that the something similar but more pronounced would have been seen.

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https://www.bbc.co.uk/news/business-47622721

 

"Boeing's Dennis Muilenburg, who is the chairman, president and chief executive of the company, said in an open letter: "Soon we'll release a software update and related pilot training for the 737 Max that will address concerns discovered in the aftermath of the Lion Air Flight 610 accident.""

 

"There will also be changes to the cockpit warning systems, the flight crew operating manual will be updated and there will be computer-based training for pilots."

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That was an interesting read. Firstly there are significant system differences in the new aircraft, secondly for operators with more than one marque of 737 pilots can be expected to fly both marques. Interestingly it looks like the QRH (check list) has a simple drill where this is treated as a stabiliser trim runaway. Hold the column, electric trim, disconnect autopilot and auto-throttle. If no result, hold trim wheel and operate both stab trim cut-out switches then manually trim (good luck with that).

 

That should give back control of sorts. As I remember all the Boeings had a similar drill but the 737 (I never flew the 727 or 747) was the only one with a trim wheel that flew backwards and forwards as the electric trim was operated.

 

I would have expected a competent crew to deal with a runaway trim, not easy but not difficult either. The key is the exposure to the failure in the simulator and familiarity with the QRH. My company had a three year cycle so that every failure was covered in the simulator. Every flight I scanned drills in the QRH and did a touch drill that gave a comfortable familiarity. I also committed to memory the pitch angle against power settings to give basic climb/descent level flight if no speed indication.

 

I once had a full nose down trim command on a Q400 which is computer controlled. The column load took both pilots to hold in the cruise. It was better lower and slower but made the approach interesting. I ended up fixing it on the phone to engineering by going to the computer cabinet and doing what I was told by the engineer then doing a maintenance check on the flight computer which showed the problem fixed. I then flew the aircraft back to base with no problems. Engineering found it ok.

 

What price a computer controlled car. Not for me.

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That was an interesting read. Firstly there are significant system differences in the new aircraft, secondly for operators with more than one marque of 737 pilots can be expected to fly both marques. Interestingly it looks like the QRH (check list) has a simple drill where this is treated as a stabiliser trim runaway. Hold the column, electric trim, disconnect autopilot and auto-throttle. If no result, hold trim wheel and operate both stab trim cut-out switches then manually trim (good luck with that).

 

That should give back control of sorts. As I remember all the Boeings had a similar drill but the 737 (I never flew the 727 or 747) was the only one with a trim wheel that flew backwards and forwards as the electric trim was operated.

 

I would have expected a competent crew to deal with a runaway trim, not easy but not difficult either. The key is the exposure to the failure in the simulator and familiarity with the QRH. My company had a three year cycle so that every failure was covered in the simulator. Every flight I scanned drills in the QRH and did a touch drill that gave a comfortable familiarity. I also committed to memory the pitch angle against power settings to give basic climb/descent level flight if no speed indication.

 

I once had a full nose down trim command on a Q400 which is computer controlled. The column load took both pilots to hold in the cruise. It was better lower and slower but made the approach interesting. I ended up fixing it on the phone to engineering by going to the computer cabinet and doing what I was told by the engineer then doing a maintenance check on the flight computer which showed the problem fixed. I then flew the aircraft back to base with no problems. Engineering found it ok.

 

What price a computer controlled car. Not for me.

 

Thanks for those explanations. So what are we saying here in layman's terms? That if you know what you're doing you can re-obtain control by overiding the system is that it?

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Thanks for those explanations. So what are we saying here in layman's terms? That if you know what you're doing you can re-obtain control by overiding the system is that it?

 

I think so, but that it's difficult if you aren't prepared for it!

 

I seem to recall some years ago now that a pilot on a rear three engined aircraft (DC-10/tristar?) was able, following mechanical failure to alter the attitude of the nose by adjusting the relative power to the lower 2 and upper single engine. I'm not sure that could ever be anticipated by a program. Ultimately I think I'd be happier for a human to intervene after accurately identifying the problem (i.e. not Captain Keys or the Air France disaster..).

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I think so, but that it's difficult if you aren't prepared for it!

 

I seem to recall some years ago now that a pilot on a rear three engined aircraft (DC-10/tristar?) was able, following mechanical failure to alter the attitude of the nose by adjusting the relative power to the lower 2 and upper single engine. I'm not sure that could ever be anticipated by a program. Ultimately I think I'd be happier for a human to intervene after accurately identifying the problem (i.e. not Captain Keys or the Air France disaster..).

 

The accident you’re thinking of is often referred to as the ‘Sioux City accident’ and is a fantastic example of crew management and resourcefulness. In terms of mechanics and checklists, there aren’t any similarities with the max accidents but it was an interesting situation.

 

It’s hard to fully understand what Boeing have engineered with this MCAS system but if it is making the aircraft pitch down and ignoring pitch inputs from the pilots, that’s a pretty big design flaw. Classic/NG pilots would be familiar with the trim runaway procedures but it sounds like the Max behaves differently and for different reasons.

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Thanks. I think that's the point I meant, allowing the input of the pilot, whereas in the recent cases it seems the system thought it knew best. In the Staines crash I referred to the crew incorrectly over-ruled the stall warnings. The dynamics in the recent case seem more complicated.

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I saw that. Seems to support the view of a Qantas pilot I was talking to a few days ago.

 

He suggested that, the plane was thought to be so failsafe that some airlines are pushing very inexperienced pilots into them without proper training on procedures for overriding autopilot and taking manual control.

 

Sent from my Pixel using Tapatalk

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Latest from another article regarding the two aircraft: they both didn't have an angle of attack indicator which is an optional extra..

 

'The angle of attack indicator will remain an optional extra that airlines can buy, according to the New York Times report.

 

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

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Latest from another article regarding the two aircraft: they both didn't have an angle of attack indicator which is an optional extra..

 

'The angle of attack indicator will remain an optional extra that airlines can buy, according to the New York Times report.

 

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

 

Not really. The aircraft comes with a pitch limit indicator as standard, which would indicate if a stall attitude was being approached. All aircraft have sensors installed, it's just displayed differently and wouldn't have helped in this scenario.

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Hold the column, electric trim, disconnect autopilot and auto-throttle. If no result, hold trim wheel and operate both stab trim cut-out switches then manually trim (good luck with that).

 

That should give back control of sorts. As I remember all the Boeings had a similar drill but the 737 (I never flew the 727 or 747) was the only one with a trim wheel that flew backwards and forwards as the electric trim was operated..

 

Am I right in thinking that those trim wheels on the 737 have no power assistance, so you're trying to fight the wheel against aerodynamic forces manually?

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  • 1 month later...

A Boeing insider involved in the design and development of the 737 Max, who is now an FBI informant in a criminal investigation into the company,

said: “We were under pressure to minimise any changes to cut costs, and to get it done quickly. In my view Boeing was making decisions on the

basis of share price.”

 

In 2011, Boeing learned that American Airlines was about to order 200 A320 Neos – a newly re-engined plane from their biggest competitor Airbus.

 

The revelation sent Boeing into a tailspin. In a desperate attempt to match its competition, Boeing pitched a new version of one of their most reliable

aircraft – the Boeing 737, which had already been revamped multiple times since its launch in 1967.

 

Impressed with the upgrade, dubbed the “737 Max” American Airlines agreed to split its new order between Airbus and Boeing.

 

But as 60 Minutes revealed, upgrading the old 737 was easier said than done. The Max’s new fuel efficient engines were too big to fit beneath its

50-year-old body design – so they were moved forward and up.

 

But Boeing discovered that moving the engines caused a lift effect that forced the plane’s nose up – risking a stall, which can cause an aircraft to

literally fall from the sky.

Boeing relied on the 737 Max not requiring airlines to upskill pilots. (60 Minutes)

 

“Boeing knew the engine design and placement would make the aircraft pitch up, with an increased risk of stalling especially at low speed.’ the insider

said. ‘But we were too close to certification to change the design,”

 

Boeing’s fix came in the form of a computer program called MCAS - the Manoeuvring Characteristics Augmentation System. This new flight control

system would automatically force the plane’s nose down if it detected an imminent stall. Critically, Boeing’s designers made MCAS reliant on just

one sensor – contrary to most aircraft safety systems, which rely on two or more sensors.

 

For the rest of this story:-

https://www.9news.com.au/national/60-minutes-inside-boeings-disaster-737-max-aircrafts/f5875c13-57d6-4957-8bf6-a0c47ddfe293

 

 

.

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  • 4 weeks later...
https://www.bbc.co.uk/news/business-48503610

 

"Boeing has warned airlines about potential flaws on the wings of some 737 aircraft, including on the new-generation 737 Max that was grounded after two crashes."

 

"The Federal Aviation Administration Authority (FAA) added that the issue arose due to an "improper manufacturing process"."

 

That’s not really news TBH. Stuff like this happens all the time, the media have just picked up on it because it effects the 737. It’ll probably just end up in an airworthiness directive, requiring more frequent inspections until the parts are replaced.

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  • 2 months later...
  • 3 weeks later...

For his birthday, my wife arranged for our youngest to have a "lesson" on a fully operational 737-800 simulator this morning. Sitting as 'passengers' we could watch everything and all the instruments as the instructor assisted him through taking off from East Midlands, a touch and go landing at Liverpool, ( that is down and straight up again without stopping, not a dodgy one ), then landing at Blackpool. Gives you a bit of an insight into how things operate in commercial cockpits, especially where the automated functions kick in, ( ie watching the trim wheels spinning, mechanisms that are indirectly linked to the issues with the Max8 ).

Edited by badgerx16
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  • 1 month later...
For his birthday, my wife arranged for our youngest to have a "lesson" on a fully operational 737-800 simulator this morning. Sitting as 'passengers' we could watch everything and all the instruments as the instructor assisted him through taking off from East Midlands, a touch and go landing at Liverpool, ( that is down and straight up again without stopping, not a dodgy one ), then landing at Blackpool. Gives you a bit of an insight into how things operate in commercial cockpits, especially where the automated functions kick in, ( ie watching the trim wheels spinning, mechanisms that are indirectly linked to the issues with the Max8 ).

 

I did always like the Krypton factor's landing a jumbo jet!

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A very,very long article about problems caused by Boeing management over the years. At the start there is a link for

you to listen rather than take time to read this article.

 

https://newrepublic.com/article/154944/boeing-737-max-investigation-indonesia-lion-air-ethiopian-airlines-managerial-revolution

 

Thanks, very interesting and I have just read all of it. There is a link in there to an Al Jazeera video about Boeing and its corporate culture. The Dreamliner unveiling is quite revealing. Apparently the plane they showed was just an empty mock-up with plywood doors and visible gaps. One quote from a former worker:

 

“The Boeing Company is all about the Big Lie”

 

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  • 2 years later...
20 hours ago, Sheaf Saint said:

Just watched the Netflix documentary "Downfall" about this subject.

It's heartbreaking. There's a special place in hell reserved for the Boeing executives who considered their share value to be of greater importance than passenger safety. 

Using "Jedi mind tricks" on the FAA is a novel corporate approach.

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  • 1 year later...
2 hours ago, Lighthouse said:

Not a great start to the year for Boeing, this happening three days after Airbus proved the A350 was built like a Soviet tank.

A day before, my son flew an Alaskan Airlines Max9 up to Anchorage. He did say it felt a bit drafty FFS

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https://www.bbc.co.uk/news/world-us-canada-67909417

"Alaska Airlines placed restrictions on the Boeing plane involved in a dramatic mid-air blowout after pressurisation warnings in the days before Friday's incident, investigators say.

The jet had been prevented from making long-haul flights over water, said Jennifer Homendy of the US National Transportation Safety Board (NTSB)."

Edited by badgerx16
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Merging with McDonnell Douglas was the worst thing that happened to Boeing, taking on their McKinsey-clone managers who had killed MD in the first place, and losing the engineering-led geeky approach that had served them so well and given them a strong safety record. Compare it to MD’s disastrous DC10 which fell out of the sky killing hundreds because they were too stingy to design a decent cargo door or put the hydraulic lines somewhere less likely to be easily severed so the plane was uncontrollable. When Boeing fucked up a tail repair for the JAL disaster in 1985 they just put up their hands up, no excuses. No blaming the operatives at the airport as MD seemingly tried to do. 

Mirrors the decline of America’s greatness in a lot of ways, shareholders over quality and customers every time. 

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  • 2 months later...

"It said the 62-year-old had died from a "self-inflicted" wound on 9 March and police were investigating."

The coroner seems sure it was self inflicted, saving police time in that investigation from having to look for time consuming things, such as other parties being involved. Case closed. 🙂

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1 hour ago, Holmes_and_Watson said:

"It said the 62-year-old had died from a "self-inflicted" wound on 9 March and police were investigating."

The coroner seems sure it was self inflicted, saving police time in that investigation from having to look for time consuming things, such as other parties being involved. Case closed. 🙂

 

 

  • Haha 1
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