Posted on 05/04/2019 2:26:46 AM PDT by CondoleezzaProtege
In the wake of two recent crashes seemingly caused by Boeing's design decisions for their 737 Max 8 and Max 9 airplanes, is it any wonder that people are concerned about Boeing's new models, the 777-8 and 777-9, that feature folding wing tips?
The new planes are scheduled for delivery in 2020...
The reason for the folding wing tips is that the wingspan of the new aircraft, at 235 feet, is too long to fit at the gates of most airports. Once folded, the wings will be only 212 feet in length. The purpose of the longer wing is to reduce drag caused by vortices, or wake turbulence, that form at an aircraft's wing tips. The less drag, the greater the fuel efficiency, and the more cheaply the aircraft can be operated.
According to Boeing, the wings will only fold when the plane is on the ground, and jet fuel will not be stored within the folding sections. Normally, jet fuel is stored within the wings of an airplane. For years, military planes on aircraft carriers have had folding wings so that they take up less space.
To get approval for the folding wing from the U.S. Federal Aviation Administration, Boeing submitted a "Special Conditions" request, and the final decision by the FAA was made public on May 18, 2018 in the Federal Register...
This document has some pretty sobering language regarding the 777-8's and the 777-9's new design:
"Boeing has determined that a catastrophic event could occur if the Model 777-8 and 777-9 airplane wingtips are not properly positioned and secured for takeoff and during flight. In service, numerous takeoff operations with improper airplane configurations have occurred due to failures of the takeoff warning systems, or inadvertent crew actions.
Then there's this;
Boeing 737 slides into Florida river with 136 on board, no fatalities
Never ceases to amaze me the weather they'll fly in.
They had 40 seconds to figure things out and do everything perfectly in that time.
...
The Ethiopian crew had a lot longer than 40 seconds to figure out the situation.
Why did the captain enable the autopilot with the stick shaker going off?
Why did the captain retract the flaps with the stick shaker going off?
Why did the captain not diagnose or attempt to diagnose why the stick shaker was going off?
Why did neither pilot continue to use the electronic trim on the control wheel to keep the plane trimmed properly? That switch overrides MCAS. Why did they not trim the plane properly before disabling electronic trim?
Why did neither pilot monitor their speed and let the plane get into an overspeed condition? Why did they leave the throttles at 94%?
Had they pulled back on the throttles MCAS would have been disabled.
People have been misled by the Fake News who is focusing solely on Boeing.
I’m not the one who is ignorant.
Devastator = slow motion death trap....
I just wonder if Boeing can survive thd 737 Max thing. I think the public will refuse to fly on them ever. That is a LOT of inventory to ge[t] restocked with no buyers.We're talking about a $100 million airplane, not a pair of shoes. Boeing is not going to 'take back' the aircraft, and the vast majority of the 5,000 737 MAX aircraft that are on back order will be delivered.
5,000 aircraft times $100 million each equals $500 billion dollars in revenue. Boeing has an incentive to get the MAX right.
Boeing has already completed the software update, flight tested it, demonstrated it to all of their major airline customers, and has submitted it to the FAA and international governmental bodies for certification and subsequent MAX return to service.
Because of the international regulatory bodies, Boeing is now estimating late July to early August to get approval.
I know orders have halted and production stopped. The inevitable lawsuits from airliners are already queuing up.
Boeing has not halted MAX production. They have slowed production and delayed the planned increased production rate.
You are correct, Boeing is going to face a lot of lawsuits, both from the families of the victims, and from airlines like Southwest that had to park their new aircraft. Boeing has almost $7 billion cash on hand as of the end of Q1 2019, so they are in an OK position to settle those lawsuits.
“In the wake of two recent crashes seemingly caused by Boeing’s design decisions for their 737 Max 8 and Max 9 airplanes”
Actually that is a half truth unless you are using a very unspecific broad use of the term “design decisions”.
The half of that statement that is not true applies to the physical design, the integrity of the fuselage, wings and engine components to fly well together and sustain the aircraft’s integrity at the desired speeds and weight load.
The one half that is true is in the far too sophisticated, overly complex software designed to remove human decision making from having to control critical functions that jet aircraft pilots have been trained to control for decades, without that sophisticated software.
It was not that the plain could not fly and fly well without some of the overly sophisticated software they installed. It could have. But nearly all companies are being taken over by the arrogant technologists to whom the rest of the company is taught to bow as if the technologists were their high priests.
When stick shaker is going off, you fly the plane. In this case, keep climbing. That is what the crew did.
Retracting flaps and engaging autopilot are standard procedure for takeoff. Stick shaker was coming from an AoA sensor that was damaged and giving erroneous readings.
They used electronic trim, but 5 seconds later, MCAS dialed in more nose down. They trimmed again. When they stopped to evaluate, MCAS dialed in full nose down trim.
Boeing gave MCAS authority to give full nose-down trim. That is criminal. The software “fix” will limit how much nose-down trim MCAS is allowed to provide.
Boeing then allowed MCAS to operate on only one AoA sensor...the sensor that got damaged. That is bad design when all other systems have multiple sensors for disagree.
The software “fix” will use both AoA sensors and if they disagree by more than a certain amount, MCAS will be disabled and a message provided to the flight crew.
MCAS put in more nose-down than the electric trim could reverse. The manual trim wheel could not move due to aerodynamic pressures across the surface and the typical procedure to “roller coaster” and manually trim could not work since they were so close to the ground.
Boeing did not disclose enough about MCAS initially. It provided poor documentation and training (iPad). Southwest Airlines discovered that all its manuals for the 737 Max were wrong because Boeing decided to change things on MCAS at the last minute and not inform the customers.
If you want to defend Boeing, go ahead. But any system, hidden from pilots, designed to change stick feel that can also trim into full nose-down, is criminal.
For those who may have some doubt about folding wing's
I tried to put the actual video in the above link, I don't think it's (the link) is working. So if you want to see F4U Corsair Wings Unfolding, here's the link: https://s3-us-west-1.amazonaws.com/hmt-forum/f4u_corsair_wings_unfolding.mp4
Retracting flaps and engaging autopilot are standard procedure for takeoff. Stick shaker was coming from an AoA sensor that was damaged and giving erroneous readings.
...
The captain didn’t know the AOA sensor was the problem, so the rest of what you’re saying is irrelevant. He never should have enabled autopilot and retracted the flaps without knowing why the stick shaker was going off. Leaving the flaps extended would have prevented MCAS from activating.
If the captain knew the problem was with the AOA sensor, he could have switched the primary displays to the sensors on the other side of the aircraft and they would have continued flying safely.
The captain had no clue why the stick shaker was going off. He and the other pilot made multiple errors that the Fake News is ignoring.
One other error they made that I didn’t list before was they could have held on to the trim wheel to prevent MCAS from adjusting trim.
I wouldn’t worry about the wings. They come from Boeing’s outstanding engineers. The redesigned 777 should be as good as the redesigned 737 MAX. After all, the feds trust them enough that they don’t require full certification if the builder re-cycles the number from a different plane design.
That was before WWII, right?
The old white star with the red center. The red center was removed in the early years of the war when some thought it was a red meat ball-—that is, a Japanese aircraft.
Forgotten the Gimli Glider?
I guess I'd start with the weight-on-wheels switch so that the wings can only be folded when the aircraft is on the ground.
One note to add. By the time the fright crew of Ethiopian Air made their fatal final mistake (turning the Electric Trim back on and not turning it off as soon as they got the plane back into acceptable trim), they had both the stall warning blaring and the overspeed warning blaring, plus possibly other warnings.
I knew a guy who died when one wing of his F-4 folded on takeoff. The WSO’s ejection was good (barely) but the pilot died. A variety of errors went into it, and of course, a bijillion F-4s took off without the error. There was also an F-4 that flew when BOTH wings folded after takeoff.
Going with a single sensor input instead of a 2 of 3 design was a physical design choice, and is the base cause of the deaths. Software changes aren't going to truly fix the problem unless they add sensor. They can provide workarounds, and that appears to be the easy, cheap path they are taking for the fix.
As someone who’s an Executive Platinum member of a major airline, and who grew up in a family of military and commercial pilots, and who raised a son who is an aerospace engineer working on the Mars project, I can tell you I will NOT board a 737 Max even after re-cert.
I refuse to fly a commercial airframe that can not maintain level flight without a software “fix”.
Who ever heard of such a newfangled thing?
It'll never work ...
Apparently the 737 has two AoA sensors, and the base model MCAS alternates between instruments for each flight. There is an option for an AoA display, and with this, the MCAS uses both. I believe it is disabled when the sensors are not in agreement.
When I design logic at work, I like using triple redundant instrumentation with voting for trip circuits and median select for analog values.
However, I have read about an A320 crash due to AoA sensors. It had three sensors. Two failed in the same position and the flight control computer ignored the one good sensor. It stalled and crashed.
Perhaps the sensor disagreement kicking a system out of auto is the better way to go here...
What kind of pilots just landed a plane in the water?
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