Environmental News

we get it, we get it

good thing they're going all electric over there

 

Source: Southwest is adding new angle of attack indicators to its 737 Max fleet - The Air Current

"Currently, the MAX and NG have an AOA disagree light that provides an alert of erroneous AOA data" ...​

Published in Nov 29, 2018.

Source_2: https://www.bizjournals.com/dallas/news/2018/11/08/southwest-american-airlines-warning-boeing-737-max.html

By Staff report
Nov 8, 2018, 10:51am EST
Southwest and American Airlines are making sure their pilots know how to respond to a potential sensor failure that’s at the center of an investigation into the crash of a Boeing 737 Max aircraft in Indonesia last week.

Boeing (NYSE: BA) issued a service bulletin on Tuesday that instructs pilots how to work through sensor problems that could cause dangerous dives when aircraft are being piloted manually, as reported by the Dallas Morning News.

The Federal Aviation Administration followed up Wednesday with an emergency airworthiness directive.​

Bob Wilson

 

USA Today reports there have been eleven u.s. pilot complaints about the planes behavior and training manual since the first crash

 

From what I've read, the whole problem comes from trying to put a 69" (175cm) fan in an application for a 40" (101cm) fan. 10lbs of sugar? Meet the 5lb sack.

So now they dangle the engines way out front, jack up the front wheel to keep them out of the mud, and they don't tell the pilots about the new center of thrust vs mass relationship? And add software that could potentially emulate a slow runaway trim?

They had already engineered a better way- telescopic landing gear to allow clearance for the big breathers. They could have kept their old thrust geometry, pod clearance, even the fuselage & gear bays stay the same. Some ground gear might have to change for the new cabin height. But stilts-on-demand isn't cheap, so they backed down.

I realize that Boeing is trying very hard to not actually make airplanes given how deeply subcontracted these are but that seems like entirely too much "not-making". They need to clean up their act.

I understand that a lab in France (Toulouse?) has the recorders from the Ethiopian Air wreck and that they are proceeding with data recovery. I'm hopeful for a clear reading such that everyone can learn and proceed.

 

aren't we all

 

Probably also to Boeing Field / King County Airport, which has more parking.

A bit over an hour's walk.

 

not all pilots are created equal. weather conditions vary as well. it sounds like this plane has some poor characteristics that can be overcome with skill in most situations, but that does not seem to be the best way to design a new airplane.

 

Not all airline training programs, maintenance programs, and adherence to safety protocols, are created equal. Lion Air was one of many airlines whose poor histories and practices got it banned from most First World operations for a while. Though they clawed their way back on to the approval lists not long ago. But even before their 737M8 crash, I would have been reluctant to fly on any of their aircraft, regardless of model.

That said, 3 consecutive Lion Air crews apparently did respond correctly (though not necessarily immediately) to the ongoing situation that the ground crews were unable to diagnose and repair. (Maybe the model's troubleshooting documentation and procedures were also inadequate?)

But the 4th crew ...

That skill is supposed to be trained in to them, to follow the aircraft's flight manual and flip that automatic system to 'Off' if/when it misbehaves. Then fly the plane the old fashioned way, manually. Crew #4 failed to switch it off.

Earlier local news reports indicated that this sort of behind-the-scenes, hidden-from-pilots automatic flight control system is relatively unusual for Boeing, but normal for Airbus which has many more similar automatic systems. (Maybe the former is not yet proficient at designing and wringing out such systems? ) But Boeing's change from its traditional design philosophy certainly wasn't adequately called out to the regular pilots.

The Lion Air flight data, clearly showing conflicting reading from the two AOA sensors, practically screams out a clue before the plane ever left the ground. Software could easily be programmed to detect this clue and respond to it somehow, but Boeing's MCAS system does not currently do so. Southwest Airlines opted for the feature to light up a warning indicator in front of the pilots to alert them to this sensor conflict, Lion did not.

I haven't yet had time to read about EA's history and reputations on these sorts of things. The EA flight data recorder is now in French hands, where it appears that the investigators went home for the night. Apparently not urgent enough to get to work on it immediately.

 

Seattle Times's complete 737 Max coverage: 737 MAX | The Seattle Times

 

It seems that a response to the disappearance of Malaysian Flight 370 -- commercial aircraft are now required to continuously report their positions by satellite -- quickly provided critical details about this EA flight's path, before the flight data recorders have been read. Such service was available at the time of the MH370 incident, but the carrier saved money by not subscribing. That choice is no longer allowed.

 

The planes are parked and they don't work for or own Boeing stock.

Bob Wilson

 

This is bringing to light some issues that Boeing and the industry in general would obviously have preferred to remain hidden.

It always takes a tradgedy for humans to do the right thing

 

So you have two, AoA sensors and they disagree:

• average the two - at least the plane will continue to fly without sudden changes in attitudes
• switch between - the good one tries to maintain flight, the bad one wants to do 'something bad'

Just speculation.

Bob Wilson

 

* Watch them both during the takeoff roll, before the nose wheel leaves the ground, when there is a 'ground reference' for AOA. In the Lion Air incident, one of them was already very obviously whacked during this phase of the journey. Unfortunately, that was also the one driving MCAS. Software could / should have set it aside as known-bad.