Value Collector
Have courage, and be kind.
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More people have died in Toyota’s than in Boeing’s.
Sure the Max might have an issue, but as I said it is likely to be fixed.
Boeing 737 Max: Death Aircraft
- Thread starter Garpal Gumnut
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More people have died in Toyota’s than in Boeing’s.
Sure the Max might have an issue, but as I said it is likely to be fixed.
Garpal Gumnut
Ross Island Hotel
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It's all to do with perception.
While I agree with you re Toyotas ( I refuse to even travel as a passenger in one ) it is different with airplanes.
While your Prius when everything goes to crap may wobble all over the place there is an even chance that you may run in to Mr and Mrs Ryobi's Aussie front lawn and just damage a dachshund.
A fault while trying to gain altitude after take-off is much more serious in an aircraft.
The Boeing 737 Max is a dead duck, as it should be.
They modified the engine weight to it's maximum, causing pitch problems by poor positioning under the wing and expected to get out of gaol with software.
Bugger them.
gg
Value Collector
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How many people die each year flying commercial flights around Australia?
How many people die each year driving on the freeways?
Check the statistics and you will find planes are a lot safer.
If there is a fault there is a fault, as I said it can be fixed.
I nothing more really to add the the discussion, except to say time will tell.
CanOz
Home runs feel good, but base hits pay bills!
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It's disappointing that it appears that not only did Boeing take short cuts in order to have a speed to market advantage, but the FAA looks to have been complicit in ensuring that advantage....time will tell. Meanwhile there's airbus.
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and that is why it has not been re-certified.
Very little similarity between this 737 and the original 60's certification.
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Airbus have had there fair share of sensor/computer issues contributing to near misses and accidents, eg. erroneous pitot tube data sending Qantas passengers heads through the luggage compartment roof, air France flight 447 going down.
So_Cynical
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Air France pilot error and incredibly bad timing (captain sleeping) funny how the auto pilot turns itself off just when you actually need it, i mean the Boeing computer knows when dodgy/conflicting info is coming in, the Max has a AOA conflict warning light as an optional extra.
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Pitot tube ice over giving wrong air speed started it off. Pilot yanking back on the stick finished it. Airbus had a problem with pitot tubes before the crash.
The Max AOA warning light optional extra is very ordinary. Even worse is that they could have compared the 2 available AOA sensors and if an error was occurring turn it off.
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Not the real reason but interesting nevertheless.
The positioning of the engines is not the underlying problem that caused those terrible mishaps.
The positioning of the engines is not the underlying problem that caused those terrible mishaps.
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CanOz
Home runs feel good, but base hits pay bills!
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That's not what the video says at all...did you even watch it?
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Care to enlighten us as to the real cause?
The MCAS ( Maneuvering Characteristics Augmentation System) was developed for the 737 Max aircraft with the sole purpose to compensate for unique handling characteristics (tendency to nose up and stall) due primarily to the new engine location forward on the wings.. The old 737 aircraft did not have this MCAS system which activates without pilot input.
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Competition is a great thing isn't it ?
Great when you are buying a TV or a cafe meal, not so good if your life is at stake.
Great when you are buying a TV or a cafe meal, not so good if your life is at stake.
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Sorry,
Just pointing out the video is full of errors. The MAX does not have a tendency to nose up and stall. MCAS was designed to subtlety trim the aircraft to resemble the NG's handling characteristics, not much difference between the two.
In the recent accident, multiple events in the cockpit may have overwhelmed the crew. Stick shaker / airspeed split between left and right systems / stabilizer moving in the opposite direction to pilot's elevator command / overspeed clacker going off / power was cut to the stabilizer motors and the pilot's attempt to manually trim using trim wheels gave the appearance of a jammed stabilizer, can't see how this is possible giving the huge mechanical advantage, trim power appeared to then be reinstated.
Apparently multiple cases of pitch down events occurred in the US, maybe handled by high time pilots who have flown many generations of 737's and simply hit the stabilizer trim cutouts manually trimming back to next base.
The fix is near, possibly improved AOA sensors, dual AOA input to the MCAS system with the system auto disabled if a split occurs, less aggressive auto control, improved pilot training.
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In spite of recent events, rather be going Boeing than take a Bus anytime !!
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CanOz
Home runs feel good, but base hits pay bills!
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Prove what you're saying is not just your opinion.
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The first bit is common knowledge, airliners these days don't have a tendency to pitch up and stall.
The second bit, you can read the official prelim report for yourself if you're genuinely interested.
The third bit, no proof, news articles I have read over the months.
The fourth bit, no proof, purely my opinion, we'll find out shortly.
BTW, most of the stuff I have read on this thread is opinion.
The second bit, you can read the official prelim report for yourself if you're genuinely interested.
The third bit, no proof, news articles I have read over the months.
The fourth bit, no proof, purely my opinion, we'll find out shortly.
BTW, most of the stuff I have read on this thread is opinion.
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Which is really just your opinion too....
Boeing 737 Max Unsafe to Fly: New Scathing Report by Pilot and Software Designer
A pilot with 30 years of flying experience and 40 years of design experience rips decisions made by Boeing and the FAA.
Gregory Travis, a software developer and pilot for 30 years wrote a scathing report on the limitations of the 737, and the arrogance of software developers unfit to write airplane code.
Travis provides easy to understand explanations including a test you can do by sticking your hand out the window of a car to demonstrate stall speed.
Design shortcuts meant to make a new plane seem like an old, familiar one are to blame.
This was all about saving money. Boeing and the FAA pretend the 737-Max is the same aircraft as the original 737 that flew in 1967, over 50 years ago.
Travis was 3 years old at the time. Back then, the 737 was a smallish aircraft with smallish engines and relatively simple systems. The new 737 is large and complicated.
Boeing cut corners to save money. Cutting corners works until it fails spectacularly.
The original 737 had (by today’s standards) tiny little engines, which easily cleared the ground beneath the wings. As the 737 grew and was fitted with bigger engines, the clearance between the engines and the ground started to get a little…um, tight.
With the 737 Max, the situation became critical. The engines on the original 737 had a fan diameter (that of the intake blades on the engine) of just 100 centimeters (40 inches); those planned for the 737 Max have 176 cm. That’s a centerline difference of well over 30 cm (a foot), and you couldn’t “ovalize” the intake enough to hang the new engines beneath the wing without scraping the ground.
The solution was to extend the engine up and well in front of the wing. However, doing so also meant that the centerline of the engine’s thrust changed. Now, when the pilots applied power to the engine, the aircraft would have a significant propensity to “pitch up,” or raise its nose. This propensity to pitch up with power application thereby increased the risk that the airplane could stall when the pilots “punched it”
Worse still, because the engine nacelles were so far in front of the wing and so large, a power increase will cause them to actually produce lift, particularly at high angles of attack. So the nacelles make a bad problem worse.
I’ll say it again: In the 737 Max, the engine nacelles themselves can, at high angles of attack, work as a wing and produce lift. And the lift they produce is well ahead of the wing’s center of lift, meaning the nacelles will cause the 737 Max at a high angle of attack to go to a higher angle of attack. This is aerodynamic malpractice of the worst kind.
It violated that most ancient of aviation canons and probably violated the certification criteria of the U.S. Federal Aviation Administration. But instead of going back to the drawing board and getting the airframe hardware right, Boeing relied on something called the “Maneuvering Characteristics Augmentation System,” or MCAS.
It all comes down to money, and in this case, MCAS was the way for both Boeing and its customers to keep the money flowing in the right direction. The necessity to insist that the 737 Max was no different in flying characteristics, no different in systems, from any other 737 was the key to the 737 Max’s fleet fungibility. That’s probably also the reason why the documentation about the MCAS system was kept on the down-low.
Put in a change with too much visibility, particularly a change to the aircraft’s operating handbook or to pilot training, and someone—probably a pilot—would have piped up and said, “Hey. This doesn’t look like a 737 anymore.” And then the money would flow the wrong way.
When the flight computer trims the airplane to descend, because the MCAS system thinks it’s about to stall, a set of motors and jacks push the pilot’s control columns forward. It turns out that the Elevator Feel Computer can put a lot of force into that column—indeed, so much force that a human pilot can quickly become exhausted trying to pull the column back, trying to tell the computer that this really, really should not be happening.
MCAS is implemented in the flight management computer, even at times when the autopilot is turned off, when the pilots think they are flying the plane. In a fight between the flight management computer and human pilots over who is in charge, the computer will bite humans until they give up and (literally) die. Finally, there’s the need to keep the very existence of the MCAS system on the hush-hush lest someone say, “Hey, this isn’t your father’s 737,” and bank accounts start to suffer.
Those lines of code were no doubt created by people at the direction of managers.
In a pinch, a human pilot could just look out the windshield to confirm visually and directly that, no, the aircraft is not pitched up dangerously. That’s the ultimate check and should go directly to the pilot’s ultimate sovereignty. Unfortunately, the current implementation of MCAS denies that sovereignty. It denies the pilots the ability to respond to what’s before their own eyes.
In the MCAS system, the flight management computer is blind to any other evidence that it is wrong, including what the pilot sees with his own eyes and what he does when he desperately tries to pull back on the robotic control columns that are biting him, and his passengers, to death.
The people who wrote the code for the original MCAS system were obviously terribly far out of their league and did not know it. How can they can implement a software fix, much less give us any comfort that the rest of the flight management software is reliable?
So Boeing produced a dynamically unstable airframe, the 737 Max. That is big strike No. 1. Boeing then tried to mask the 737’s dynamic instability with a software system. Big strike No. 2. Finally, the software relied on systems known for their propensity to fail (angle-of-attack indicators) and did not appear to include even rudimentary provisions to cross-check the outputs of the angle-of-attack sensor against other sensors, or even the other angle-of-attack sensor. Big strike No. 3.
None of the above should have passed muster. It is likely that MCAS, originally added in the spirit of increasing safety, has now killed more people than it could have ever saved. It doesn’t need to be “fixed” with more complexity, more software. It needs to be removed altogether.
With the 737 Max, the situation became critical. The engines on the original 737 had a fan diameter (that of the intake blades on the engine) of just 100 centimeters (40 inches); those planned for the 737 Max have 176 cm. That’s a centerline difference of well over 30 cm (a foot), and you couldn’t “ovalize” the intake enough to hang the new engines beneath the wing without scraping the ground.
The solution was to extend the engine up and well in front of the wing. However, doing so also meant that the centerline of the engine’s thrust changed. Now, when the pilots applied power to the engine, the aircraft would have a significant propensity to “pitch up,” or raise its nose. This propensity to pitch up with power application thereby increased the risk that the airplane could stall when the pilots “punched it”
Worse still, because the engine nacelles were so far in front of the wing and so large, a power increase will cause them to actually produce lift, particularly at high angles of attack. So the nacelles make a bad problem worse.
I’ll say it again: In the 737 Max, the engine nacelles themselves can, at high angles of attack, work as a wing and produce lift. And the lift they produce is well ahead of the wing’s center of lift, meaning the nacelles will cause the 737 Max at a high angle of attack to go to a higher angle of attack. This is aerodynamic malpractice of the worst kind.
It violated that most ancient of aviation canons and probably violated the certification criteria of the U.S. Federal Aviation Administration. But instead of going back to the drawing board and getting the airframe hardware right, Boeing relied on something called the “Maneuvering Characteristics Augmentation System,” or MCAS.
It all comes down to money, and in this case, MCAS was the way for both Boeing and its customers to keep the money flowing in the right direction. The necessity to insist that the 737 Max was no different in flying characteristics, no different in systems, from any other 737 was the key to the 737 Max’s fleet fungibility. That’s probably also the reason why the documentation about the MCAS system was kept on the down-low.
Put in a change with too much visibility, particularly a change to the aircraft’s operating handbook or to pilot training, and someone—probably a pilot—would have piped up and said, “Hey. This doesn’t look like a 737 anymore.” And then the money would flow the wrong way.
When the flight computer trims the airplane to descend, because the MCAS system thinks it’s about to stall, a set of motors and jacks push the pilot’s control columns forward. It turns out that the Elevator Feel Computer can put a lot of force into that column—indeed, so much force that a human pilot can quickly become exhausted trying to pull the column back, trying to tell the computer that this really, really should not be happening.
MCAS is implemented in the flight management computer, even at times when the autopilot is turned off, when the pilots think they are flying the plane. In a fight between the flight management computer and human pilots over who is in charge, the computer will bite humans until they give up and (literally) die. Finally, there’s the need to keep the very existence of the MCAS system on the hush-hush lest someone say, “Hey, this isn’t your father’s 737,” and bank accounts start to suffer.
Those lines of code were no doubt created by people at the direction of managers.
In a pinch, a human pilot could just look out the windshield to confirm visually and directly that, no, the aircraft is not pitched up dangerously. That’s the ultimate check and should go directly to the pilot’s ultimate sovereignty. Unfortunately, the current implementation of MCAS denies that sovereignty. It denies the pilots the ability to respond to what’s before their own eyes.
In the MCAS system, the flight management computer is blind to any other evidence that it is wrong, including what the pilot sees with his own eyes and what he does when he desperately tries to pull back on the robotic control columns that are biting him, and his passengers, to death.
The people who wrote the code for the original MCAS system were obviously terribly far out of their league and did not know it. How can they can implement a software fix, much less give us any comfort that the rest of the flight management software is reliable?
So Boeing produced a dynamically unstable airframe, the 737 Max. That is big strike No. 1. Boeing then tried to mask the 737’s dynamic instability with a software system. Big strike No. 2. Finally, the software relied on systems known for their propensity to fail (angle-of-attack indicators) and did not appear to include even rudimentary provisions to cross-check the outputs of the angle-of-attack sensor against other sensors, or even the other angle-of-attack sensor. Big strike No. 3.
None of the above should have passed muster. It is likely that MCAS, originally added in the spirit of increasing safety, has now killed more people than it could have ever saved. It doesn’t need to be “fixed” with more complexity, more software. It needs to be removed altogether.
