CAA bans Boeing 737 max 8

I used to fly gliders. One of my acquaintances was a pilot who had worked for BAe amongs other aerospace companies. Whilst sitting in the crew bus / canteen (an old USAF bus without an engine) on a wet day we were chewing the fat about the then fairly new fly-by-wire systems.

The question was raised about what you did if the computer went titsup. The answer was that there was an emergency manual over-ride which would allow you to, as he put it, enter Piper Cub mode, i.e. full manual reversion.

As long as you either had sight of the horizon and / or the basic working instruments (altimeter, airspeed, artificial horizon, direction, turn & bank & vertical speed) you could fly the thing and had a good chance of a safe landing.

He also flew with a pilot who would insist on his co-pilot doing at least every other takeoff and landing in full manual mode to gain experience. He loved it, but a lot of the younger pilots hated being forced to do it manually.
 
So; is a malfunctioning AoA sensor a reason to ground a quarter-billion-dollar investment? Because insisting that absolutely zero faults are allowed on any part of the aircraft, no shades of gray allowed, seems... interesting.

Would a malfunctioning AoA sensor be regarded as a potential cause of a crash, for an older 737? Was the significance of the sensor made clear in conversion training for the type? Because AFAICT, the answer is no...

This is the root of the problem - if you're selling an aircraft as "it's just the same as the previous version, no expensive retraining required" (for maintainers, not just pilots), should you maybe consider adding something in BIG SCARY CAPITALS that says "Actually, it's REALLY important to realise that if the AoA sensor fails, ground the aircraft, or MCAS will crash it and kill you".

Except that isn't the case. The case when the AoA sensor fails is to fly the plane like a pilot that actually knows how to fly.

Set trim manually when the plane starts to slightly nose up. What a pilot would normally do. Period. The problem appears to be that these pilots do not know how to be a pilot.

"something is causing the plane to point up in the sky a little bit at a time for half an hour til it stalls" is not exactly, "aw shucks, it'll go, put some duct tape on it and don't tell no one" territory.

So, you are saying you think that people's lives are not important enough to be concerned about when there is a malfunction of a critical nature, you only care when it can be reworked to let yourself off the hook and used as an effective tool in competition for business.
 
Except that isn't the case. The case when the AoA sensor fails is to fly the plane like a pilot that actually knows how to fly.
...ahhh, victim blaming. Remind us, how long did the Ethiopian airlines aircraft have to realise what was going wrong and to fix it? On an aircraft that was behaving counterintuitively, and unlike the standard 737 that he had over 8,000 hours on type? "It keeps putting the nose down"? The pilot declared an emergency 180 seconds into the flight, it crashed 180 seconds later, with the horizontal stabilizer in full nose down angle.

Set trim manually when the plane starts to slightly nose up. What a pilot would normally do. Period. The problem appears to be that these pilots do not know how to be a pilot.
Well, several national aviation authorities disagree with you, otherwise they wouldn't have grounded the type. Probably because flight control systems that actively try to kill you are a bad idea.

So, you are saying you think that people's lives are not important enough to be concerned about when there is a malfunction of a critical nature, you only care when it can be reworked to let yourself off the hook and used as an effective tool in competition for business.
Can't be Boeing's fault, dammit, because American! Hell, Yeah! Must be those incompetent yahoos who can't pilot! Except... the FAA disagrees with you. They've grounded it, because dangerous. If it was pilot error, the type would still be flying.

Who to believe? The FAA and NTSB, or a bloke on the internet? Tricky, that...
 
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...ahhh, victim blaming. Remind us, how long did the Ethiopian airlines aircraft have to realise what was going wrong and to fix it? On an aircraft that was behaving counterintuitively, and unlike the standard 737 that he had over 8,000 hours on type? "It keeps putting the nose down"? The pilot declared an emergency 180 seconds into the flight, it crashed 180 seconds later, with the horizontal stabilizer in full nose down angle.
The system can only correct about 2.6 degrees over that time period, and there is no way a properly functioning unit could ever go full down angle.

And no. Yared Getachew supposedly had 8000 with SOME time on 737s, and never trained on the Max 8 simulator that Ethiopian Airlines had installed. I will not guess at what percentage of time he has on older 737s, but it is a sure bet that the large majority of those hours was doing something else with the autopilot actually flying. He obviously didn't know how to manually set trim on ANY 737 as setting trim would have solved the issue, if MCAS was the issue.

Ethiopian Airlines Had a Max 8 Simulator, but Pilot on Doomed Flight Didn’t Receive Training On It

Well, several national aviation authorities disagree with you, otherwise they wouldn't have grounded the type. Probably because flight control systems that actively try to kill you are a bad idea.
Your hysterical overstatement of the situation does not look good. We ground aircraft systems for 1 crash all the time. The fact that the Lion Air jet should have been grounded, and the fact the EA pilot did have the benefit of notification of the potential issue through FAA warnings on the previous crash, as well as the proper simulator to train on, but that he did not do any training on the Max 8 is a real issue. THE CORRECTION FOR THE ISSUE ON MAX 8 IS THE SAME AS IT HAS ALWAYS BEEN on any 737, regardless of the fact that additional sensors were added and more computing time was assigned to modify the profile for the change in engines and cg.

What isn't known is if the EA plane had previously exhibited problems and not been grounded as well.


Can't be Boeing's fault, dammit, because American! Hell, Yeah! Must be those incompetent yahoos who can't pilot! Except... the FAA disagrees with you. They've grounded it, because dangerous. If it was pilot error, the type would still be flying.

Who to believe? The FAA and NTSB, or a bloke on the internet? Tricky, that...
Again, we ground planes for 1 or 2 accidents all the time... The facts are you are ignoring most of the facts that point to failures of the parties with the most responsibility to take any responsibility.

Boeing, on the other had, has already taken responsibility with respect to potential perception issues, and has already initiated changes.
 
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Since I wanted to make sure I wasn't being totally unreasonable in my position, I went did a little digging, and I found a recent article by Mac McClellan in the Air Facts Journal through a different article in The Atlantic that was mainly about a trip through the NASA Aviation Safety Reporting System.

From McClellan's Article...

What the much ballyhooed system in the 737 MAX does is sense an increasing AOA when the pilot is hand flying the airplane. When the AOA reaches a point without enough stall margin, the system adds some nose-down pitch trim. That pitches the nose down and gives the pilot the stick force to know that he is pulling too close to the stall margin.

This concept of adding artificial feel using the pitch trim has been around for years. It has been used to add stick force at high speed cruise where Mach effects can alter stick force as well as at higher AOA where stall margins must be maintained.

What’s critical to the current, mostly uninformed discussion is that the 737 MAX system is not triply redundant. In other words, it can be expected to fail more frequently than one in a billion flights, which is the certification standard for flight critical systems and structures.

What Boeing is doing is using the age-old concept of using the human pilots as a critical element of the system. Before fly-by-wire (FBW) came along, nearly all critical systems in all sizes of airplanes counted on the pilot to be a crucial part of the system operation.

The certification concept for relying on the human involves identification of a failure, and a reaction time. The way it works is that the pilot must be able to recognize the failure, then take three seconds to analyze what is wrong, and then take corrective action before the airplane flies into a critical condition.

If you fly an airplane with an electric pitch trim system, you are flying under this certification concept. A pitch trim system running away can obviously fly the airplane into a dangerous condition, particularly when the autopilot is engaged which masks the trim runaway for some time.

Circuit breakers
The proper reaction to a trim or autopilot problem is the same in a 737 or a 210 – push the button and pull a breaker.
The manufacturer seeking certification of the trim system and the FAA agree on what it will take to allow the pilot to identify a trim failure. It could be the airplane deviating from the desired flight path. Or a trim monitoring system with enough redundancy. Or, in years past, simply seeing the trim wheel moving on its own could have been enough.

Experimental test pilots introduce the trim failure, wait for the agreed identification condition, and then wait three more seconds before taking the prescribed recovery actions. In all airplanes I know of, the recovery is—including the 737 MAX—to shut off the system using buttons on the control wheel then a switch, or sometimes circuit breaker to make a positive disconnect.

Though the pitch system in the MAX is somewhat new, the pilot actions after a failure are exactly the same as would be for a runaway trim in any 737 built since the 1960s. As pilots we really don’t need to know why the trim is running away, but we must know, and practice, how to disable it.

The problem for Boeing, and maybe eventually all airplane designers, is that FBW avoids these issues. FBW removes the pilot as a critical part of the system and relies on multiple computers to handle failures.

Boeing is now faced with the difficult task of explaining to the media why pilots must know how to intervene after a system failure. And also to explain that airplanes have been built and certified this way for many decades. Pilots have been the last line of defense when things go wrong.

What makes that such a tall order is that FBW airplanes – which include all the recent Airbus fleet, and the 777 and 787 from Boeing – don’t rely on the pilots to handle flight control system failures. FBW uses at least a triple redundant computer control system to interpret the inputs of the cockpit controls by pilots into movement of the airplane flight controls, including the trim. If part of the FBW system fails, the computer identifies the faulty elements and flies on without the human pilots needing to know how to disable the failed system.

I know, I know, you’re yelling, “What about the Air France Airbus over the Atlantic?” It was determined that all three pitot tubes on the airplane froze robbing the FBW system, and the human pilots, of airspeed and other air data at night and in an area of thunderstorms. The pitot tubes were thought to have enough heat to prevent that, but those extreme conditions were outside the certification envelope. And certification theory also thought the engines on the Airbus Sully and Skiles were flying were far enough apart that large birds wouldn’t take out both. Was that one in a billion? Probably.

I have been fortunate enough to fly several FBW airplanes and I find the simplicity and excellent flying qualities, weight savings, and potential efficiency gain, to be an important advance. But, as a pilot, I also want to believe that being part of the redundant requirements for critical systems is still acceptable.

But airline accidents have become so rare I’m not sure what is still acceptable to the flying public. When Boeing says truthfully and accurately that pilots need only do what they have been trained to do for decades when a system fails, is that enough to satisfy the flying public and the media frenzy?

...
 
The CBC have obtained a copy of the Boeing 737 Max 8 flight manual, and the only reference to the MCAS system is a very brief mention in the table of abbreviations.
737 Max flight manual may have left MCAS information on 'cutting room floor' | CBC News
In the over 1,600-page flight manual of Boeing's 737 Max 8 planes, the aircraft's new MCAS computer system, now at the centre of the investigations into two deadly crashes, is mentioned only once by name — in the glossary of abbreviated terms.


An aviation consultant said that he suspects the MCAS was explained in an earlier draft version of the manual, but this was cut from the final version.
"I think the fairly obvious conclusion is that a broader explanation of MCAS was included in an earlier edition of the manual, and somewhere along the way it ended up on the cutting room floor," said Judson Rollins, a New Zealand-based aviation consultant, who worked for three airlines and a plane manufacturer.
He believes it was cut in order to avoid having to include the MCAS in the transition training, to save costs. Including the MCAS in the manual would imply that it was significant enough that pilots would need classroom or simulator based training. This would add hundreds of thousands to millions of dollars to the cost of the plane.
Rollins believes it was cut "to prevent the MCAS from having to be included in 737 Max transition training, which in turn will save 737 Max operators training costs."

But Rollins said that including MCAS in the manual would suggest it was a significant enough system that pilots would need to undergo classroom- or simulator-based training.

Costs for that extended training, he said, could range anywhere from hundreds of thousands of dollars per plane to the low millions.
Data from the Ethiopian Airlines flight recorder shows "clear similarities" with the Lion Air crash.
The crash of Ethiopian Flight 302 on March 10 and that of a Lion Air plane in Indonesia in October — both of them Boeing 737 Max 8 jetliners — has prompted Canada, the U.K. and other countries to ground the aircraft. According to investigators, data obtained from the flight data recorder in the Ethiopian crash reveal "clear similarities" with the Lion Air plane disaster.
 
Oh well, that's good of them. No need for lawsuits then.

'The US planemaker Boeing has said it will give airlines a free software update to rectify issues with the anti-stall system which is believed to be the root cause of the two crashes of the Boeing 737 Max aircraft which lead to the global grounded of the type.'

Air101: Boeing to give free software fix to 737 Max 8 customers
 

Goatman

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Book Reviewer
Can't be Boeing's fault, dammit, because American! Hell, Yeah! Must be those incompetent yahoos who can't pilot! Except... the FAA disagrees with you. They've grounded it, because dangerous. If it was pilot error, the type would still be flying.

Who to believe? The FAA and NTSB, or a bloke on the internet? Tricky, that...
Back in the 90's, Boeing introduced a new software based controller for Chinook helicopters - FADEC if I recall.

It was extensively tested at what was then the Aircraft & Armaments Evaluation Establishment Boscombe Down, which was also home to the Empire Test Pilot School (ETPS) and various other niche aviation testing outfits.

There was quite a bit of to-ing and fro-ing prior to the FADEC software being permitted on RAF Chinooks...not least because Boeing refused to release the source code for evaluation by a Third World operation such as...er...the Royal Air Force....

Chinook ZD576: How the Fadec engine control software worked and what could have gone wrong

Boscombe Down's IT specialists were so concerned about the Chinook Mk2 software that they had recommended a rewrite - but this did not happen before the aircraft went into operational service. Soon after Chinook ZD576 went into service with the new Fadec system it crashed and the pilots were blamed.


<Cough: Arrogant twats >
 

Goatman

ADC
Book Reviewer
I hope that comment is refering to Boeing.
Yes.....Boscombe had a very good reputation at the time, not sure what it's like now.

I was not aware of the tensions between Boscombe and Odiham.
 
There was quite a bit of to-ing and fro-ing prior to the FADEC software being permitted on RAF Chinooks...
My combined-arms course as an ambitious Captain was in the mid-90s, after ZD576; and the big exercise included tanks an guns an demo troops an... three Chinooks. Our rifle coy piles into the waiting wokkas; before we take off, the loadmaster walks to where I'm sitting near the back, and checks something in the ceiling. Because I was nearby, I noticed that this was a box of electronics, with a helpful state indicator LED showing a number through a little window. The label on the lid of the box suggested it was FADEC-related. Being a bright lad, I knew that this meant HC.2...

It appeared (to this particular engineer, at least) was that SOP on the new Chinook was to carry out an additional visual check that the FADEC definitely thought it was working, independent of the cockpit instrumentation, before taking off. Not worrying at all...

...of course, I felt it necessary to share the information to my course colleagues that yes, this was indeed "one of those Chinooks". Git that I was.

Meanwhile, a f**king Biggles! dit. A couple of hours later, a Chinook is tasked to move our Company the couple of km forward (in three lifts) to act as reserve Coy in the BG attack on Imber. First lift gets TAC HQ and a platoon in for me to hear the CO's QBOs. Second lift... declares a breakdown halfway, kicks the talking baggage out, and f**ks off. We've now got 45 minutes until H-hour for the BG attack, and a Company spread across three locations and 2km. The CSM and last platoon arrived with five minutes to spare, for the fastest Coy QBOs I've ever given...
 
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Software issues perhaps?

'Boeing has delayed the first spaceflight of its CST-100 Starliner crew capsule for at least four months, according to reports.
The original target date for the uncrewed test mission to the International Space Station (ISS) was for April, however it has now been pushed back until August at the earliest, as reported by Reuters.
Reuters cited unnamed industry sources, who claimed that both technical and scheduling issues played a part in the delay.
Boeing and NASA declined to comment on the report, however NASA said it will be publishing an updated launch schedule at some time this week.'


Boeing delays first spaceflight of crew capsule
 
The US transport minister is questioning why Boeing didn't include some optional safety features as standard in the 737 Max.
U.S. transport chief asks why some Boeing safety features not included | CBC News
"I don't think we are there yet, but it is very questionable if these were safety-oriented additions, why they were not part of the required template of measures that should go into an airplane."
And an influential US senator who will be the chair of a committee looking into the issue, Ted Cruz, has said that a major area of inquiry will be into the certification process which allowed Boeing to sell the plane in the first place.
Sen. Ted Cruz, a Texas Republican, will chair the hearing later on Wednesday. "Another major area of inquiry is the process of certification of the 737 Max to begin with," he said on CNBC.
"Why didn't this process catch this problem if this was the cause of the accident?"
There are apparently plans in the works to overhaul the way the US FAA operates to improve how aircraft certifications are done.
Calvin Scovel, the U.S. Transportation Department inspector general, will testify the FAA will significantly change its oversight approach to air safety by July.
At the same hearing, the acting administrator of the FAA, Dan Elwell, will tell a Senate commerce committee panel the agency's oversight approach must "evolve."
Scovel's testimony for the hearing first reported by Reuters says that in response to a 2015 inspector general report, the FAA agreed to improve oversight of organizations performing certifications on its behalf.
 
I'm no avionics expert but do Boeing believe that a few 'software fixes' rushed out in the weeks following two high profile fatal aircraft accidents are going to inspire a renewed confidence in the safety of the 737 Max?
Isn't it called 'Beta-testing'?
 
I'm no avionics expert but do Boeing believe that a few 'software fixes' rushed out in the weeks following two high profile fatal aircraft accidents are going to inspire a renewed confidence in the safety of the 737 Max?
Likewise no specialist, by any means, but are these fixes the ones Boeing said, a few weeks ago, were already in hand before the Ethiopia crash, but their certification / authorisation was held up by the closure of Govt departments (Boeing dixit) and would be issued 'soon'?
 

Goatman

ADC
Book Reviewer
I can imagine the scene....' okay guys, let's BLAMESTORM this problem '
 

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