Define “clearly”.

It really isn’t much different. At this point in the career you really should be able to figure it out pretty quick. I personally don’t need my hand held for several days to figure out the landing gear lever is in a different spot or a blue light is omitted.

MCAS doesn’t operate, or is not supposed to operate when the autopilot is on? Well maybe the MCAS isn’t supposed to operate when the autopilot is engaged but isn’t the whole issue about a “flaw” in the system?

If aircraft are pitching down for no reason then it would seem to me a system is not functioning as designed. Something is amiss. Maybe it’s a flaw, maybe it’s a training issue - maybe it’s a little bit of both. Either way we will know more shortly.

Scoop

I don’t know what the whole issue is about. None of the investigations are complete.

The Lion Air incident, and possibly the Ethiopian Airlines incident, is looking like the primary cause might be linked to a single point of failure (an AOA vane) causing the activation of the previously undisclosed MCAS system while at the same time presenting the pilots with a host of distracting and confusing indications.

-The stick shakers would be activated without the ability to silence them for the duration of the flight (unless the CB’s were pulled).

-Possible invalid airspeed indications (not sure how a bad AOA vane is processed and then displayed to the pilot’s by the air data computer).

-Probably the red and yellow stall bars are biased up, contributing to the pilots (along with the stick shaker) thinking they’re in a stall.

-Nose down trim is being applied by MCAS while all of this is going on. Imo, there’s a good chance this wouldn’t even be recognized at first since the pilot’s brains are probably on fire trying to figure out wtf is going on with stick shakers and airspeed indications. They might think the increasing nose-down weight of the yoke has something to do with being in an actual stall.

-It would be a lot to process. We also don’t know for sure right now that there might not be some other indications or failure modes that contributed to one or both accidents. Lion Air has not issued a final report and Ethiopian Is only at the very initial stages of determining what happened. To me, it makes sense to ground right now. Two brand new airplanes crashing within less than five months of each other is likely not a coincidence (especially when there are only approx 300 MAX’s currently delivered).

Wasn't it VMC? Why not look outside, use pitch and power and get your head out of the cockpit?
Foreign carriers rely heavily on automation. When it doesn't work planes crash.
Not saying there wasn't a problem with a system but there sure is a problem with lack of flying skills in countries developing avaiation.

^^^^^^This, exactly.

I tend to agree that any US crew, who is actually flying a MAX today, should be able to deal with this.

But the public does not understand the nuanced distinction between foriegn and US pilot cultures and experience. Onviously public perception and confidence in the aviation system is important, so the grounding was probably the right thing to do. I heard a rumor the USG was looking at some information sources to rule out explosives/terrorism since there were rumors of that and some bizarre eyewitness reports. Apparently nothing found along those lines, so combined with Lionair, reasonable (not conclusive) suspicion that the plane has an issue.

Pitch and Power works if the aircraft is responding as predicted to your inputs.

In this failure case, it sounds like the MCAS system would be repeatedly pitching the aircraft nose down while you're trying to bring the nose up. Being VMC would've just give you a better view of the roller coaster ride while you're desperately trying to wrap your head around the situation.

Btw, as I understand it, there were previous Lion Air crews who were able to deal with a similar failure, no?

After the Air France iced over pitot probe crash (which btw more than one foreign crew had dealt with adequately previously), every airline in the world started introducing that scenario to their crews in the sim and most crews including those in the US had difficulty initially, until the training highlighted the correct response.

Studies have shown that our flying skills are eroding as a result of more reliance on automation. But that's not unique to the rest of the world. It is very much the case in the US too..

The solution obviously is that every pilot should make the effort once in a while to kick off the automation and get back in touch with our airplanes.

Could anything have to do with a jet designed in the 1960's being stretched and pushed beyond its actual design limits? Trying to make the 737 into a 757 without design costs of a new jet?

Because you can’t use pitch and power when MCAS is doing what it’s doing unless you kill the trim switches. The MCAS is operative WHILE handflying
The issue is recognition of what’s happening.
Air speed unreliable while the stick shaker is going crazy nose pitches down at 1k feet AGL?
You’re telling me that with the current training, you’d figure out what’s going on? You click off autopilot and it gets WORSE? Unless you’ve had training on the system...aside from a CBT.

I think that a lot of the Monday morning quarterbacks here should wait for the final results of both investigations before judging the pilots' skills. How easy to criticize those who can't defend themselves. Try also imagining the situation at low altitude when your airplane is aggressively trimming forward, your attitude indicator is showing excessive pitch up, stick shaker is going on, you continuously keep overriding the nose down pitch with your stab trim. As I understand from the little information we got about the MCAS, you can override the auto trim forward with your stab trim switch, but the moment you let go off the switch it immediately trims back down. So you have the trim spinning back and forth (thus the oscillations in both accidents) at low altitude and low airspeed. No memory items to turn of the stab trim cutout switches. Not too much time to run QRH, not enough training and information about the system. Some say the other crew that brought the Lion Air airplane the day prior successfully ran the checklist and turned the stab trims switches off. It's true, but they were much higher, during a descent with completely different aircraft energy and attitude. Think what you want, but I consider blaming the crews for being not experienced or not well trained as scapegoating. I think Boeing created the problem and they should assume the responsibility. And for all you great aviators that have so much experience, think about what they went through right after you take off. Add night conditions or IMC if you like...

I wouldn't say .27°/second of nose down pitch is aggressive. We take off using 2-3° of nose up pitch per second and that is in no way aggressive.
http://www.b737.org.uk/mcas.htm

Try to imagine being a low altitude and not knowing how to manually trim the airplane. If either of these crews had been able to do that, the airplanes would still have been flyable.

They had the ability to correct the trim--but some pilots method of trimming an airplane is to turn on the autopilot. As far out of whack that the MCAS seems to put the trim, the autopilot would not be able to turn on--or not have authority to keep the airplane in level flight.

TTFA -- if you're a pilot and don't know that acronym, you're part of the problem.

I had to look it up.

You sir are evil.... funny, but evil :D

Agree with this very much ^^^^^

Also looked it up - Thenoyltrifluoroacetone

Still no idea what that is.

Question: when MCAS is operating, does the "stab wheel" also turn?

I assume it does.

Seems logical. It's trimming and the wheel turns any other time it's happening. But, I don't know for certain.

[QUOTE=Bwipilot;2782435],,,,Try to imagine being a low altitude and not knowing how to manually trim the airplane. If either of these crews had been able to do that, the airplanes would still have been flyable.......

/QUOTE]

yeah...so easy.

plane gets grounded worldwide by pretty much everyone, including manufacturer.

define, unclear, re: B737 Max airworthiness.

good lord...i just answered the question, imo, people care aboiut company profits cause they work for the company.

frankly, i thought its pretty obvious.


i totally answered out of context. My fault.

How about an aural chime or alert whenever the MCAS system is activated?

Yep, you put your thumb on a button on the yoke and trim to relieve the pressure on the controls--in this case the pressure being induced by MCAS.

Trim the F'ing Airplane

Hmm. I’m guessing they tried that.

Yeah, we all know how trimming works, except the moment "you put your thumb" off the yoke it starts trimming forward. You can't "relieve the pressure" because MCAS identifies high pitch (remember, one AOA vane is stuck, or broken) and will continue pitching forward unless either: you are trimming against it; the AP is engaged (it can't because two different conflicting AOA pitch information disable it); or the system is disabled by stab trim cutout switches. So you're down to flipping the switches. How often do we touch them? Should we run QRH or just flip them because it's the only option? How often do we flip switches without flows or checklists? It's really easy to say: they were bad/inexperienced pilots, I would have easily recovered, trimmed the airplane and wouldn't even break a sweat. Me, the real pilot, easy-peasy...

Those switches were a memory item on all 4 Boeings I have flown. So....”we” flip switches when the situation dictates. i.e. runaway stabilizer

You can't relate it to pitching during takeoff. The MCAS system is moving the stab trim .27 units per second, for 2.5 units total in approx 10 seconds. It's not targeting a pitch rate change.

Whats happening to the SWA Max Pilots? Are they getting a paid vacation? Or can they just step back down to flying the standard 737-800?

It’s all one type rating

We don’t understand the system well enough collectively, and that’s part of the problem

The way I understand it, MCAS is disabled with the autopilot on or flaps extended. Seems putting the flaps back to 1 would stop the MCAS also

737 Max is safe
 

Based on the information that is available at this point I would say the 737 Max is safe. The preliminary report on Lion Air Flight 610 states that the previous crew dealt with the same failures and handled them according to the way every 737 pilot is trained: Airspeed unreliabe and runaway stabilzer memory items:

The PIC cross checked both PFDs with the standby instrument and determined that the left PFD had the problem. The flight was handled by the SIC.

The PIC noticed that as soon the SIC stopped trim input, the aircraft was automatically trimming aircraft nose down (AND). After three automatic AND trim occurrences, the SIC commented that the control column was too heavy to hold back. The PIC moved the STAB TRIM switches to CUT OUT.

An interesting fact is that the crew suspected the runaway stabilzer was caused by the speed trim system since they did not know about the existence of MCAS. The Pic wrote in the Tech log:

STS* also running to the wrong direction, suspected because of speed difference


This shows that even though the crew wasn't aware of the MCAS system they still knew how to handle it malfunctioning, which makes sense to me since it doesn't matter what causes a stab trim runway it just matters to stop it from happening (nonetheless I share the criticism that Boeing should have made crews aware of the system).
I would hate to have unreliable airspeed coupled with trim runaway but the Lion Air 610 crew was in the air for more than 10 Minutes which seems like enough time to to set the stab trim cut out switches to cut out.

As opposed to the way the media is reporting it, the MCAS System isn't going to be active in a normal flight. It is a system that will aid in a critical situation which under normal circumstances will not occur. If a system that is designed to aid the pilots malfunctions it is our job to recognize this and shut off the system. This I believe is not going to change anytime soon.
Nonetheless I do agree that it would be an improvement if MCAS received information from both AOA sensors.

About the reports that several pilots already faced problems with the MCAS system as was spread by news media througout the world. Looking at the reports the Dallas morning news refered to, they misinterpreted the reports. There is one report about the autopilot behaving unusual after it was engaged. There were two reports made about this one incident: one by the Captain and one by the First Officer. The media falsely reported this as two seperate events. Furthermore, according to our present knowledge MCAS will not be activated when the AP is engaged and the crew even wrote that they cannot rule out a mismanagement of the AP. The other reports about not setting FL 360 when cleared to this level or the thrust not being set as expected are the kind of reports that you will find plenty of for any given airplane.
So we are left with no report concerning a malfunctioning MCAS experienced by US pilots which is the opposite of what the media reported (one pilot rightly complained about the lack of documentation for MCAS).
Considering that we do not know yet what caused the Ethiopian crash and that the information about the Lion Air crash suggests that it was preventable, I find the grounding of the 737 Max unjustified and believe the airplane is safe to fly.

It will come down to certification basis.
Boeing, at the request of SWA, Alaska Airlines and to a varying degree the big Three, rushed out a response to the A320/321 NEO.
In doing so they discovered that a big under-slung engine on a longer pylon created deleterious effect on maneuver margins near the edge of the envelope. Lacking any type of an intelligent maneuver-assistive FCC they strapped one on to essentially a manual system. And broke all their own rules about critical Flight Control design. Single source, no fail-safe, no comparator, no false-input control. Nothing but a QRH. Having pushed up against the limits of simple common type, they and their airline partners convinced the FAA that these changes were simple and not only did not require training but really only mechanics need know of them. No need to point it out to pilots as it would just confuse them. Nothing should happen and if it does it will be hidden under the general Runaway Stabilizer Trim QRH...

No question that all of us with extensive experience could wrangle the jet into submission and go land. But the certification basis requires the 200hr guy to wrangle the jet noy us

Breach of Faith, loss of confidence by airlines, Boeing and the FAA for sure. Unflyable jet...by no means

MCAS I think was a good idea but poorly implemented.

First - it should be disabled and not activate if there's an airspeed disagree or any detected issue with AOA indicators. That's a simple fix. Frankly this system activating during such a circumstance is just exacerbating an already existing emergency.

Second - it should not be allowed to get to full nose down trim below a specific altitude - Boeing can decide what that altitude is but I'd say 10000 feet and certainly not 6000.

The purpose of MCAS is to help with stall recovery with high power settings. Tests could be performed to determine what the max nose down trim should be with full power, but I'm certain it's not FULL nose down trim. Limit it.

I think that this can be fixed and the fleet safely returned to service. I'm sure smarter people than me at Boeing have already considered what I'm proposing.

Interesting that the FAA’s B-737 Flight Standardization Board Report (FSB Report) does not identify any required Differences Training or Special Emphasis Items with respect to the MCAS system on the -Max vesus previous models?

www.fsims.faa.gov, under Publications, FSB Reports, Boeing.

I still want to know if in fact the two crews were approaching stall conditions in the first place.

Now the investigators are arguing over stuff and walking out of meetings in France. Hopefully the real answers come out.