Boeing 737 Max is safe to fly again, Europe’s aviation regulator says

[reader]

From CNBC

Europe’s aviation regulator has declared Boeing’s 737 Max aircraft safe to fly after it was grounded in March 2019 following two accidents that left 346 people dead.

Patrick Ky, executive director of the European Union Aviation Safety Agency, told Bloomberg Friday that he’s satisfied with the changes Boeing has made to the aircraft, adding that the aircraft could return to the region’s skies before the end of 2020.

The announcement comes even though Boeing is yet to implement a software upgrade that his agency demanded. It could be two years before it’s ready.

[vinapu]

only question is where it will be flying with most flights grounded and airports half mothballed

[PeterRS]

I believe Boeing, its planners, engineers and everyone who was a supervisor on the creation of a plane which was very obviously not airworthy are guilty of the murder of 346 souls.

From the Congressional hearings and the regular excellent Pullizer prize winning reports in The Seattle Times, we know that major airworthy issues were raised by many working on the plane and routinely brushed aside by the bean counters based in Chicago. They knew the plane was not airworthy. They wilfully and deliberately concocted false narratives for the FAA and airlines first to persuade them that a plane with a 60 years old airframe and larger engines that had to jut above the wings only because they just could not raise the height of the landing gear, and second to have another 737 success story in the air.

I absolutely loved the various models of the 747. I have happily flown most other Boeing models. After three years with no self combustion, I finally took the 787 and enjoyed the flights. But I will never fly the 737 Max. If I find an airline has switched planes at the last minute and the new one is a Max, I will demand to go on another flight.

[10tazione]

19 hours ago, reader said:

From CNBC

... that he’s satisfied with the changes Boeing has made to the aircraft ...

Can those changes easily be applied to all the existing 737 Max? Is it only a software upgrade? Does anyone know?

[PeterRS]

26 minutes ago, 10tazione said:

Can those changes easily be applied to all the existing 737 Max? Is it only a software upgrade? Does anyone know?

Not sure how easily but they will have to be applied before the models already sitting idle can be permitted to fly again. Revamping the MCAS system was only one of a number of problems with the aircraft which became obvious before it got near the FAA for recertification. One was bunching of wires at the back of the aircraft which could have resulted in a fire. I believe there were also problems with the fuselage, perhaps of the same type that have now grounded at least 8 787 Dreamliners. These 787 problems are a result of production flaws at Boeing's South Carolina facility. The FAA is now investigating potential defects in that aircraft's production. 

As if that is not bad enough, there have also been concerns about the new wider longer range 777X. Unlike the 737 Max, this is a redesign and not an add on. A year ago it failed a stress test that involved bending the wings to a worst case scenario. In the same test the rear part of the fuselage depressurised and a cargo door came off the plane. At least that is how Boeing described the incident. A photo obtained by The Seattle Times and reported on CNN shows it was far worse with part of the fuselage split wide open behind the wing. That test aircraft was a write off. Despite the setbacks, Boeing kept pushing to launch the plane this year. It has now been put back to 2022.

The 777X has also had big problems with its larger GE engines. But the FAA finally certified them last month.

https://www.seattletimes.com/business/boeing-aerospace/boeing-777xs-fuselage-split-dramatically-during-september-stress-test/

 

[Guest]

An interesting question.    From what I've been reading, if they have one sensor fail, the MCAS system can put the plane into a dive.   The pilots are supposed to switch off the electric actuation of the pitch control and use a manual system (run by pulleys), but according to one report, they need to respond very quickly otherwise the aero loading becomes too high. 

I'm amazed that the plane was allowed out with a system where a single sensor going down has such failure modes. 

The equivalent system on a car is VDC/ESP, but of course it controls yaw, not pitch.   The yaw rate sensor output is compared continuously with expectations based on 4 wheel speed sensors.  Therefore, if the yaw rate sensor fails, the system shuts down and leaves a warning light, rather than causing the car to leave the road.    I'd expect the systems on an aircraft to be at least as good and more likely, have multiple sensors to provide redundancy.    It seems the systems on cars have safer failure modes.     I don't know how MCAS got through an FMEA.

I shall attempt to avoid the 737max for a few years.

Edit:  Here is a Boeing explanation.   Note the first thing they added is a plausibility check which compares input from 2 sensors.  There's no way this should have been engineered without that in the first place.

  https://www.boeing.com/commercial/737max/737-max-software-updates.page

 

[vinapu]

as we are grounded along with 737MAX , now it's good time to try to scare us from flying, LOL

[reader]

Agree with OP's position. No matter what changes were made to the Max, it's not airworthy in my book. In effect, the software is designed to make the plane believe that its oversize engines are located aft of where they actually are. A bit of computerized hocus pocus. And I, too, would not fly in this model. Have to admit that I'm surprised that EU was first out the gate to give it its blessing. Ryanair must be ecstatic. (it has 135 firm orders and as of last month was in talks with Boeing to up that number to 200). 

My favorite wide-body at the moment is the A350 which I've flown about a dozen times now.

Elsewhere on the Euro aviation front, Lufthansa has retired 14 of its 747-400 aircraft but will be retaining all 11 of its newer and larger 747-800 versions (they are currently in storage but the carrier considers them to be its "flagship" aircraft in the post pandemic environment).

Boeing 747-800

The German carrier recently disclosed its decision to retire 150 aircraft by the middle of the decade – 50 more than previously announced. Eight parked A380s have been “removed from planning” and will only be reactivated in the event of an “unexpectedly rapid market recovery”, according to Flight Global.

 

 

[PeterRS]

3 hours ago, reader said:

My favorite wide-body at the moment is the A350 which I've flown about a dozen times now.

Could not agree more. Find it more comfortable and quieter than the competitor 787 Dreamliner. Have seen the Lufthansa 747-800 at several airports but never flown it. I think very few passenger versions were completed and LH was virtually the only customer. Most others are the freighter version.

My other favourite aircraft is the A380. I am so disappointed it was the wrong plane at the wrong time.

[Guest]

In principle, there's nothing wrong with using software to improve the control of planes.   I believe that's been fairly effective in stopping pilots flying into mountains (mostly), it stops wheels locking when landing and no doubt has many other functions.

Using software to prevent too much pitch is also perfectly OK, but the software should be implemented with proper consideration of failure modes, redundancy and plausibility checks for signals.  This is all basic stuff for safety critical systems.    What Boeing did should have never got through an FMEA review.

The countermeasures are exactly the type of thing that should have been on the plane in the first place.   

I'd imagine they might have reviewed a few other systems in the time that's been taken over this.

 

I've still not been on an A380.    I took care to avoid it during the first 5 years of service and should probably try to arrange a flight whilst I can.   Right now, I would settle for a flight on almost any Boeing or Airbus long haul plane.

 

[reader]

2 hours ago, PeterRS said:

I think very few passenger versions were completed and LH was virtually the only customer. Most others are the freighter version.

Just checked Wikipedia and surprised to learn that 139 747-8's have been delivered, but--as you noted--the great majority are in indeed the 747-8F (freighter) configuration.

All 19 of Lufthansa's fleet are the passenger version (747-8i). Other carriers with the "i" are Korean Air (10) and Air China (7).

Two have been delivered to the US Air Force and are being fitted out to replace the two 747's now being used for Air Force One.

(Btw, Peter, when I said in above post that I agree "with OP's position," I should have said "with PeterRS's position." Sorry about that.

59 minutes ago, z909 said:

Using software to prevent too much pitch is also perfectly OK, but the software should be implemented with proper consideration of failure modes, redundancy and plausibility checks for signals. 

Agree, to a point. But even Boeing's engineers tried to dissuade the company from going ahead with the MAX during the design process. They cautioned that the bigger and more powerful engines were too bulky for the old 737 air frame. If the engines were positioned where they were in the earlier versions of the 737, the landing gear would leave it scraping the runway. Designers, however, were being pressed to use the 737 chiefly because it could be sold to customers as requiring no special training for pilots already licensed in that type. Hence the engines were moved more forward of the wing, creating the need for the computer to compensate for the center-of-gravity forces created by the shift.

 

[Guest]

24 minutes ago, reader said:

Two have been delivered to the US Air Force and are being fitted out to replace the two 747's now being used for Air Force One.

Yes.   They only put America's finest* in a plane with 4 engines.   I also believe he's only allowed to fly in a plane model that's had 5 years service and is built to spec, without any concessions. 

So there's no chance of a 737 max being used for Air Force One.

 

[*and the current incumbent]

[vinapu]

1 hour ago, z909 said:

 Right now, I would settle for a flight on almost any Boeing or Airbus long haul plane.

 

I'd gladly fly even 737 MAX to BKK with 4 or 5 refueling stops on the way

[reader]

Z909 wrote:

  I also believe he's only allowed to fly in a plane model that's had 5 years service and is built to spec, without any concessions. 

===================================================================

The current aircraft serving as Air Force One are versions of the 747-200 series introduced into service in 1990 when George H.W. Bush was in office. They have 30 years of service.

Not sure what your "five years of service" is referring to.

[vinapu]

14 minutes ago, z909 said:

 They only put America's finest* in a plane with 4 engines. 

[*and the current incumbent]

I sense you don't like Orange Overlord

[Guest]

15 minutes ago, reader said:

Not sure what your "five years of service" is referring to.

Whatever model he flies has to have had 5 years service, which means other customers flying the same type of aircraft to prove it has reasonable reliability.   

I try to apply the same policy, but with 737 max and A320 NEO aircraft getting mixed into fleets, it will be more difficult.  

Aircraft are amazingly safe these days & the improvement over the decades has been amazing.   However, problems on "new" aircraft designs include lithium battery fires on Dreamliners,  an A380 engine failure almost taking the wing out & the 737 max issue.

[reader]

Got it. Thank you for clarification.

[PeterRS]

6 hours ago, reader said:

But even Boeing's engineers tried to dissuade the company from going ahead with the MAX during the design process. They cautioned that the bigger and more powerful engines were too bulky for the old 737 air frame. If the engines were positioned where they were in the earlier versions of the 737, the landing gear would leave it scraping the runway. Designers, however, were being pressed to use the 737 chiefly because it could be sold to customers as requiring no special training for pilots already licensed in that type. Hence the engines were moved more forward of the wing, creating the need for the computer to compensate for the center-of-gravity forces created by the shift.

From what i read, the 737 Max f**k up was a direct result of competition from the long range Airbus A320 Neo. Boeing originally planned a totally new design for the Max, but the Neo got a head start and this got the Boeing bean counters really worried. A new aircraft can take many years to design and develop. The six decade old airframe of the 737 was deliberately close to the ground so that it could be used at smaller airports without airbridges. The original A320 on the other hand was developed much later and sits considerably higher off the ground. Competition with the Neo would require larger engines. On the old airframe they would be too close to the ground. As reader points out, the solution was to place them further forward and up to the point where they jut above the front surface of the wings. This disrupts airflow over the wings and gives the aircraft a tendency to pitch the nose up. No other aircraft has a similar design. The MCAS computerised system was developed to bring the nose back down when this occurred. But pilots were not told about it.

I also understand that the MCAS activation is dependent on the Angle of Attack (AOA) sensors. There are two on each aircraft, one on each side. But Boeing only attached one to the MCAS i.e. no redundancy. Prior to the first crash, Boeing had received more than 200 complaints from pilots about faults in the AOA sensors.

There is another piece of software related to the AOA sensors that Boeing decided to make an optional extra rather than mandatory. Cannot recall what that was. Since the grounding, it is now mandatory that this be included in all Max aircraft.

The real problem surely is that the 737 Max is inherently an unstable aircraft that is dependent on its computers and the MCAS system to ensure it can be kept stable.

 

[PeterRS]

8 hours ago, z909 said:

I've still not been on an A380.    I took care to avoid it during the first 5 years of service and should probably try to arrange a flight whilst I can.   

Please do. If possible find a short route served by the aircraft and splash out on a business class ticket. Most seats are in individual units separate from other seats. The flat bed seats are amazing, not that they would be needed on a short flight. The large vdo screens and the huge choice of IFE is truly amazing. The bar at the back is a full bar with premium liquors and snacks. I find it is usually busy on long haul flights from the USA to Dubai.

[reader]

Like most all post-crash investigations, the ones following the two MAX incidents concluded that it was a cascade of events that led to the disasters. However, the one factor not cited sums it up best: greed.

[Guest]

35 minutes ago, reader said:

 However, the one factor not cited sums it up best: greed.

To me, it looks rather like incompetence ahead of greed.

The Boeing link I posted earlier implies that there are already 2 angle of attack sensors.    So to have software that compares the output from the 2 sensors and shuts MCAS down in case of an abnormality should have negligible incremental cost.   Or more accurately, zero incremental material cost per plane and an increase in the amortized R&D cost that's so small, they probably don't even capture it. 

Generally, using software control systems to improve safety is a very good thing.  Overall, it reduces the number of accidents.    Including in aircraft, as software will be more consistent and reliable than pilots.   However, the software & systems need to be engineered properly, so that there are no nasty failure modes.   There are established processes which have been in place for decades & this error really should not have got through.

After these incidents:

1  Boeing will be much more careful over then next few decades, so the chances of something like this slipping through will be reduced.

2 The media will be all over the most minor of incidents with Boeing aircraft for the next few years.   Until they get bored with it.  We saw that with Toyota following their accelerator pedal issue.

 

 

[reader]

I guess my best counter argument is that the special sensor in question wouldn't have been necessary if there were not flaws in the design. But for aviation enthusiasts like ourselves, and perhaps some other interested readers, looking at the wealth of data in the House Committee on Transportation's Final Report on the Boeing MAX 737 may prove worthwhile. Here a snapshot of the contents:

“Our report lays out disturbing revelations about how Boeing—under pressure to compete with Airbus and deliver profits for Wall Street—escaped scrutiny from the FAA, withheld critical information from pilots, and ultimately put planes into service that killed 346 innocent people. What’s particularly infuriating is how Boeing and FAA both gambled with public safety in the critical time period between the two crashes,” Chair DeFazio said. “On behalf of the families of the victims of both crashes, as well as anyone who steps on a plane expecting to arrive at their destination safely, we are making this report public to put a spotlight not only on the broken safety culture at Boeing but also the gaps in the regulatory system at the FAA that allowed this fatally-flawed plane into service."

Final Committee Report Materials

• Final Committee Report on the Design, Development, and Certification of the Boeing 737 MAX
• Boeing Records Set One
• Boeing Records Set Two
• FAA Records
• Teal (Boeing) Transcribed Interview
• Leverkuhn (Boeing) Transcribed Interview
• Bahrami (FAA) Transcribed Interview
• Press Release on Final Committee Report

It can be downloaded at link below. But be forewarned that it contains over 600,000 individual documents collected in the course of the investigations. Fortunately it doesn't need to be downloaded as a whole. Rather select sections can be accessed.

https://transportation.house.gov/committee-activity/boeing-737-max-investigation

 

[anddy]

17 hours ago, PeterRS said:

 As reader points out, the solution was to place them further forward and up to the point where they jut above the front surface of the wings. This disrupts airflow over the wings and gives the aircraft a tendency to pitch the nose up. No other aircraft has a similar design. The MCAS computerised system was developed to bring the nose back down when this occurred. But pilots were not told about it.

[...]

The real problem surely is that the 737 Max is inherently an unstable aircraft that is dependent on its computers and the MCAS system to ensure it can be kept stable.

I didn't know about this engine shift and airflow problem and thus Peter's conclusion that it's inherently unstable at all. Thanks all contributors in this thread to present the key issues with the 737max so clearly in the small space of just one thread page.

I shall, too, endeavor to avoid this plane for quite some time. 

[daydreamer]

14 hours ago, z909 said:

The Boeing link I posted earlier implies that there are already 2 angle of attack sensors.

There are two sensors.  They are located on the outside of the cockpit, below the pilot side windows.  All large aircraft have these.  What was missing from the Indonesian and Ethiopian 737 Max aircraft were the angle of attack indicator (not sensor) and the disagree alert to alert the pilot if the two sensors do not match.  Boeing made these items optional.  Both would have been present in the cockpit if the airlines had purchased the options.  Only a few airlines purchased both options on the 737 Max.  United Airlines ordered 137 of the aircraft and none of them are equipped with either of the two options.  United says they use other data to fly their planes.

More detail can be read at the following links:

https://www.nytimes.com/2019/03/21/business/boeing-safety-features-charge.html

https://www.reuters.com/article/us-boeing-fix/boeing-says-optional-737-max-alert-was-not-activated-as-intended-idUSKCN1S5233

[PeterRS]

14 hours ago, z909 said:

To me, it looks rather like incompetence ahead of greed.

I see it as a grissly combination of both! Greed because it knew Airbus had a competitor aircraft in a more advance state of design. Instead of continung with its new 737 Max design, Boeing abandoned those plans. It made a risky decision to add much more powerful larger engines on to a six decades old airframe, even though it knew those engines could not be positioned as in all previous 737 models. But by keeping the mechanics and cockpit of the Max as close as possible to previous models, they wanted pilots to easily slip from one model to the next with a minimal of training. That is one reason why the sales pitch to customers became so hugely successful.

Knowing the above, it had no choice but to come up with a whole raft of new solutions. That's when incompetence entered the picture. Anyone who has read the whole series of articles in The Seattle Times will know that pressure from the bean counters bore down on all in change of constructing the aircraft virtually every day. Engineers admitted that corners were cut. Vital safety systems were compromised.

The MCAS became the vital system to ensure airworthiness. Boeing lied to the FAA about it. It lied to customer airlines when informing them pilot retraining and time in simulators would not be necessary for pilots. All pilots were given was a one hour presentation on an iPad. Southwest was even given a formal agreement that if simulator training became necessary, the airline would be given a rebate of US$1 million per plane. Not surprisingly both the FAA and EASA have now insisted on simulator training.