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DenverBrian Jul 12, 2019 7:59 am


Originally Posted by fly18725 (Post 31296160)


Which is why the airplane is grounded until changes are made...

There is critical loss of nuance in this discussion. Until there’s are accident reports and an understanding whether any deficiencies in design were the result of Boeing’s negligence, placing blame is hysteria.

Although it is a tragedy that people died, we have to move on.

Couldn't disagree more.

LarryJ Jul 12, 2019 12:57 pm


Originally Posted by cmd320 (Post 31296130)
Kinda like the sufficiently detailed technical explanation of MCAS that Boeing offered to airlines and operators prior to unleashing this hot mess on the world?

None of the information that has come out about MCAS since the accidents changes the way a pilot should respond to an unscheduled MCAS activation. The correct procedure is exactly the same today as it was the day the first MAX was delivered. A procedure that neither accident crew accomplished correctly; even the one who knew about MCAS.

We now have a lot of information on MCAS which is what allows us to discuss it, the implications of an unscheduled activation, and draw informed conclusions. We have no such details on this unrelated autopilot problem so can't do anything but speculate. Speculation isn't particularly productive.

While Boeing works the fix the airplane, work also must be done to understand why two properly trained crews failed to accomplish the applicable procedure. If you ignore this, choosing to just blame Boeing, you are ignoring what could be a safety deficiency as big as the original flaw in MCAS.

The two issues are completely separate and must be addressed separately. It is inappropriate try to share blame between them. They both must be fixed.

TWA Guy Jul 12, 2019 1:55 pm

United Airlines extends Boeing 737 Max cancellations to early November
 
https://www.cnbc.com/amp/2019/07/12/...-november.html
United Airlines extends Boeing 737 Max cancellations to early November
Emma Newburger @emma_newburgerPublished 2 Hours Ago CNBC.com
  • United Airlines on Friday said it will extend its Boeing 737 Max groundings through Nov. 3, amounting to 2,100 cancellations in September and 2,900 in October.
  • United, which has 14 Max jets in its fleet, had previously removed the jets from its schedule through Aug. 3.
  • The 737 Max has been grounded worldwide since mid-March, after its anti-stall software was implicated in two deadly crashes in October and March.
United Airlines on Friday said it will extend its Boeing 737 Max groundings through Nov. 3, amounting to 2,100 cancellations in September and 2,900 in October.

United, which has 14 Max jets in its fleet, had previously removed the jets from its schedule through Aug. 3.

"We are continuing to work through the schedule to try and swap and upgauge aircraft to mitigate the disruption caused by the grounding of the MAX," United said in a statement. "We continue to automatically book affected customers on alternate flights. If we are unable to place them on a different flight, we will proactively reach out to try and offer other options."

The 737 Max has been grounded worldwide since mid-March, after its anti-stall software was implicated in two deadly crashes in October and March. Other major airlines including American and Southwest have canceled thousands of flights during the busy summer travel season, and have further removed the Max from schedules through Sept. 3 and Oct. 1, respectively. Those airlines will likely further extend cancellations.

United reports second-quarter results after the market closes on Tuesday. Delta Air Lines, which does not fly the 737 Max, said on Thursday that it's seeing a small benefit as rivals grapple with the grounding.
Boeing deliveries are stopped until aviation regulators approve the jet's return to service. The airplane maker said in June that it would likely take until September or later to introduce a new software fix after the Federal Aviation Administration identified a new software issue a month ago.

cmd320 Jul 12, 2019 2:46 pm


Originally Posted by LarryJ (Post 31297228)
None of the information that has come out about MCAS since the accidents changes the way a pilot should respond to an unscheduled MCAS activation. The correct procedure is exactly the same today as it was the day the first MAX was delivered. A procedure that neither accident crew accomplished correctly; even the one who knew about MCAS.

We now have a lot of information on MCAS which is what allows us to discuss it, the implications of an unscheduled activation, and draw informed conclusions. We have no such details on this unrelated autopilot problem so can't do anything but speculate. Speculation isn't particularly productive.

While Boeing works the fix the airplane, work also must be done to understand why two properly trained crews failed to accomplish the applicable procedure. If you ignore this, choosing to just blame Boeing, you are ignoring what could be a safety deficiency as big as the original flaw in MCAS.

The two issues are completely separate and must be addressed separately. It is inappropriate try to share blame between them. They both must be fixed.

As a customer flying in the 21st century, that’s just not good enough for me. This logic maybe worked in the 1960s when pilots would occasionally drop 727s on the ground due to a lack of experience on the engines’ spool-up time. It does not work in 2019 where it is clear Boeing has designed an aircraft poorly and under pressure from some shoddy US airlines (looking at you AA) in order to certify it quickly without having to spend money to properly train flight crew. This is compounded by Boeing allowing itself to get steamrolled in the narrowbody aircraft market ever since it stopped producing the Boeing 757.

The 737MAX is nothing more than a model of the mismanagement, lack of innovation, stagnation, and desperation that runs deep in Boeing Commercial Aircraft today. They’ve just finally taken it too far. It’s really a shame because the 707, 717, original 737, 747, 757, 767, 777, and even the 787 (despite its numerous delays and build quality shortcoming) are great airplanes, and I would have no problem flying any of these aircraft today (assuming they’ve been well maintained). What I do have a problem with is when airlines and manufacturers collaborate in the name of being cheap and the FAA fails at their job of industry oversight.

Newman55 Jul 12, 2019 3:19 pm


Originally Posted by cmd320 (Post 31297552)
As a customer flying in the 21st century, that’s just not good enough for me. This logic maybe worked in the 1960s when pilots would occasionally drop 727s on the ground due to a lack of experience on the engines’ spool-up time. It does not work in 2019 where it is clear Boeing has designed an aircraft poorly and under pressure from some shoddy US airlines (looking at you AA) in order to certify it quickly without having to spend money to properly train flight crew. This is compounded by Boeing allowing itself to get steamrolled in the narrowbody aircraft market ever since it stopped producing the Boeing 757.

The 737MAX is nothing more than a model of the mismanagement, lack of innovation, stagnation, and desperation that runs deep in Boeing Commercial Aircraft today. They’ve just finally taken it too far. It’s really a shame because the 707, 717, original 737, 747, 757, 767, 777, and even the 787 (despite its numerous delays and build quality shortcoming) are great airplanes, and I would have no problem flying any of these aircraft today (assuming they’ve been well maintained). What I do have a problem with is when airlines and manufacturers collaborate in the name of being cheap and the FAA fails at their job of industry oversight.

Exactly what have Boeing "taken too far" with the Max? Please... be specific.

There is nothing physically wrong with the design of the plane. The only thing wrong are some software fixes and some training reinforcement.

cmd320 Jul 12, 2019 3:27 pm


Originally Posted by Newman55 (Post 31297639)
Exactly what have Boeing "taken too far" with the Max? Please... be specific.

There is nothing physically wrong with the design of the plane. The only thing wrong are some software fixes and some training reinforcement.

The aircraft was designed for short haul regional flying in the late 1960s. It was designed low to the ground for airports with no boarding bridges. It was not designed for large high-bypass turbofan engines in 2019. It was not designed to fly 200 people for 5-6 hours, it was designed to fly 100 people 90 minutes or less. It was not designed to have its flight characteristics augmented by a poorly designed and faulty computer system. It was not designed to be stretched a half dozed times by an incompetent company clinging on to something that’s decades old rather than investing the time and money into designing a modern, industry leading narrowbody aircraft. Boeing is falling farther and farther behind in the narrowbody market.

Newman55 Jul 12, 2019 3:37 pm


Originally Posted by cmd320 (Post 31297660)
The aircraft was designed for short haul regional flying in the late 1960s. It was designed low to the ground for airports with no boarding bridges. It was not designed for large high-bypass turbofan engines in 2019. It was not designed to fly 200 people for 5-6 hours, it was designed to fly 100 people 90 minutes or less. It was not designed to have its flight characteristics augmented by a poorly designed and faulty computer system. It was not designed to be stretched a half dozed times by an incompetent company clinging on to something that’s decades old rather than investing the time and money into designing a modern, industry leading narrowbody aircraft. Boeing is falling farther and farther behind in the narrowbody market.

So... in summary.. nothing is wrong with the plane. You just don't like it. That's cool.

You could just say that you don't like the plane for arbitrary reasons .

cmd320 Jul 12, 2019 4:38 pm


Originally Posted by Newman55 (Post 31297684)
So... in summary.. nothing is wrong with the plane. You just don't like it. That's cool.

You could just say that you don't like the plane for arbitrary reasons

No, I never liked the third generation of the aircraft to begin with. That has nothing to do with the obvious safety shortcomings of the latest iteration of it. Now that the newest version has proven itself to be critically unsafe and a deathtrap, I think it’s a crime that it was ever designed the way it was by Boeing, and ever allowed to fly with minimal certification from an inept FAA which was 10 steps behind the rest of the world in grounding what was clearly a rush-job.

VegasGambler Jul 12, 2019 4:56 pm

Here is an interesting blog post that I haven't seen here yet:

AviationSafetyPOV

It's from the beginning of April. The general gist is that he thinks that the manual trim system is poorly engineered and too difficult for pilots to use (too much force is required)

I don't want to copy too much (for copyright reasons) but here is a quote:

From a human engineering and safety standpoint, the design of the horizontal tail surfaces and the pilot’s mechanical trim system on the 737 MAX seems poorly thought out and poorly implemented. The speed at which the trim wheel runs in the simulator video seems to indicate a poor choice of mechanical advantage and mechanical ratios in the manual trim system, producing large forces that the pilots must overcome manually in an emergency and also require too many revolutions of the trim wheel to accomplish the needed trim control adjustments.

WineCountryUA Jul 12, 2019 5:17 pm

Moderator Note
This thread has been very informative to many but it has also been plagued with at times overheated discussion that has been problematic. One issue that has bothered many readers is the manner in which those that perished in JT610 and ET302 has been used as debating tooling. Many find this very disrespectful and not appropriate.

It is an undeniable fact the all perished on those two MAX 8 flights. The reasons for this are under investigation and the MAX has been grounded due to concerns over its safety. There are multiple investigations by multiple bodies worldwide.

Many posters have strong opinions of about the history and future of the MAX series. This thread has been a good place to consolidate information, learn more about how all the pieces interact and speculation about how we got here and going forward.

No one is denying this a terrible set of incidents and these deaths are tragic, but there is little need to repeatedly re-state this as everyone is quite aware of this. So going forward let's please be respectful of those unfortunate individuals and not use their deaths to attempt to paint others as uncaring or as overdramatizing the incident. Neither is helpful to the discourse or respectful to those no longer able to engage in the discussion.

Thanks

WineCountryUA
UA coModerator

Newman55 Jul 12, 2019 6:41 pm


Originally Posted by cmd320 (Post 31297830)
No, I never liked the third generation of the aircraft to begin with. That has nothing to do with the obvious safety shortcomings of the latest iteration of it. Now that the newest version has proven itself to be critically unsafe and a deathtrap, I think it’s a crime that it was ever designed the way it was by Boeing, and ever allowed to fly with minimal certification from an inept FAA which was 10 steps behind the rest of the world in grounding what was clearly a rush-job.

Again, there is nothing wrong with the physical design. {C}omplaints about the the MAX are the same complaints anyone could have about the A320.

cmd320 Jul 12, 2019 7:07 pm


Originally Posted by Newman55 (Post 31298066)
Again, there is nothing wrong with the physical design. {C}omplaints about the the MAX are the same complaints anyone could have about the A320.

The aircraft was never originally designed to be fitted with high-bypass turbofan engines. It is too low to the ground to accommodate these appropriately. The A320 (while also a pretty ancient design) does not suffer from this issue as it is two decades more modern (but by no means a modern airplane) and was built higher off the ground with expandability in mind. Boeing was able to fudge things and make it work for the 737 Classic and the NG. This process has failed with the engines required for the MAX and has resulted in catastrophic failure.

exwannabe Jul 12, 2019 7:16 pm


Originally Posted by LarryJ (Post 31297228)
None of the information that has come out about MCAS since the accidents changes the way a pilot should respond to an unscheduled MCAS activation. The correct procedure is exactly the same today as it was the day the first MAX was delivered. A procedure that neither accident crew accomplished correctly; even the one who knew about MCAS.

We now have a lot of information on MCAS which is what allows us to discuss it, the implications of an unscheduled activation, and draw informed conclusions. We have no such details on this unrelated autopilot problem so can't do anything but speculate. Speculation isn't particularly productive.

While Boeing works the fix the airplane, work also must be done to understand why two properly trained crews failed to accomplish the applicable procedure. If you ignore this, choosing to just blame Boeing, you are ignoring what could be a safety deficiency as big as the original flaw in MCAS.

The two issues are completely separate and must be addressed separately. It is inappropriate try to share blame between them. They both must be fixed.

Question Larry. How often have pilots had to use the full mechanical procedure (vs just shutting off the auto-pilot and using direct control of the electric system via the tab switches).?

Is the ability to execute it the same on the MAX? After all, you are directly wrenching up the stabalizer against the forces that might be very different on the MAX.

LarryJ Jul 12, 2019 7:33 pm


Originally Posted by exwannabe (Post 31298152)
Question Larry. How often have pilots had to use the full mechanical procedure (vs just shutting off the auto-pilot and using direct control of the electric system via the tab switches).?

Is the ability to execute it the same on the MAX? After all, you are directly wrenching up the stabalizer against the forces that might be very different on the MAX.

Not sure I understand exactly what you're asking.

I have no idea how often 737 pilots have had to use manual trim. The manual trim system is the same as what was used on the B707, B720, KC-135, B727, and all B737 aircraft. It's not commonly needed but that's a very long history so I'm sure there have been many instances where manual trim was used.

The problem that both accident crews had was that they didn't disable the electric trim until the stabilizer was at, or very near, the full nose-down position. That's a worst-case scenario and does not represent the forces that would be required for 'normal' manual trim operation. In one case, they were also over 150 knots faster than they should have been which compounded the problem by greatly increasing the aerodynamic forces on the stabilizer and the nose-down pitching moment that the stabilizer produced.

The trim wheels have a lot of mechanical advantage. Many turns of the trim wheel for very small movements of the stabilizer. Kinda like a 10-speed bicycle pedalling in first gear. In other posts I have described the methods for manually turning the wheel from low to high required turning force.

Did that answer your question?

Newman55 Jul 12, 2019 7:47 pm


Originally Posted by cmd320 (Post 31298129)
The aircraft was never originally designed to be fitted with high-bypass turbofan engines. It is too low to the ground to accommodate these appropriately. The A320 (while also a pretty ancient design) does not suffer from this issue as it is two decades more modern (but by no means a modern airplane) and was built higher off the ground with expandability in mind. Boeing was able to fudge things and make it work for the 737 Classic and the NG. This process has failed with the engines required for the MAX and has resulted in catastrophic failure.

So, Airbus engineers foresaw that high-bypass engines, like the ones designed for both the neo and the max, would exist in the late 1970s?

Again, there is nothing wrong with the physical design of the MAX, lower clearance or not. The MAX can accommodate larger engines and these larger engines have not been implicated as the cause for the accidents.


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