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Old 20th Apr 2019, 16:25
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EPHD75
 
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My Appreciation to You for Speaking

Originally Posted by L39 Guy
I think your analysis and continuum of blaming the pilots/Boeing and everyone else harmless to blame Boeing and everyone else/pilots harmless is a nice summary.

I will tell you where I sit on this, based upon 36 years of professional flying (31 airline, 5 military), type rated on B737-200/767/777/787 and Airbus A330/A340, and a Professional Engineer.

First, aircraft are amazing and complex machines. Aircraft do what man was never intended to do naturally so there is an inherent risk in that alone. But even the best designed and best maintained aircraft have components that break and the human onboard is the last line of defense in many of those instances. Hydraulic systems, electrical systems, pressurization systems, propulsion systems (engines) all fail and often there is not double or triple redundancy due to weight issues, cost issues, probability of failure and the impact of a failure. As an example, there is no level of redundancy that will offset an engine failure no matter how many engines the aircraft has; the adverse yaw, the reduced performance, etc cannot be compensated for by having more engines, although the more engines an aircraft has, the less effect a single engine failure has. Aircraft manufacturers, at the urging of their airline customers, like two engine aircraft for the economics (one engine versus two, reduced fuel, reduced weight, etc). So we accept that fact that an engine failure on a two engine aircraft will have big affect when one fails, more than a single engine failure on an eight engine aircraft.

So when an engine (or hydraulic, or electric, or pressurization) system fails a pilot is in the loop to manage the situation. That is why we are highly trained and, hopefully, well compensated financially for that knowledge and judgement. The level of training lies with the individual knowing their stuff including their emergencies, particularly emergencies that are memory items - that is a personal responsibility of any professional pilot. The airline and country CAA is responsible too for insuring that the pilots charged with responsibility for that aircraft and those lives in the aircraft are also trained properly initially and on a recurrent basis.

Where do I sit on your continuum? Somewhere between 2 and 3. MCAS is a required stall protection however it needs to be toned down a bit as it can move the stabilizer trim to very large aircraft nose down angles. Should pilots be aware of MCAS in their technical training on the MAX; sure, but it would not have affected the outcome regardless as, I will describe shortly, MCAS failure presents characteristics identical to a stabilizer trim runaway, an emergency checklist item that has been around since the original B737 fifty years ago.

I would expect that any pilot with a type rating for a Boeing 737, MAX included, should be able to identify an Unreliable Airspeed (UAS). That is basic stuff, stick shaker when the aircraft if flying normally, disparity between the indicated airspeeds, etc. Any professional pilot should be able to recognize this regardless of what aircraft they are flying as every aircraft in the world is subject to this problem.

Only 2 of the 3 non-US MCAS incidents saw the pilots recognize the UAS and do something about it. This was long before MCAS reared its ugly head so that begs the question: Why? Training and experience would be my answer. And, as it turned out, the crew that did execute the UAS drill were the ones that ultimately saved the aircraft. Bear in mind that UAS is a memory drill. To me, there is no excuse why this was not done as it was a textbook UAS; to me also, in the Ethiopian case, engaging the autopilot at 400 ft is a definite faux pas as it is contrary to the memory UAS drill and, if the aircraft was indeed stalled, another definite faux pas as one does not recover from a stall with the autopilot. This points to a training/experience issue too but it also points to an over reliance on the use of the autopilot at the expense of hand flying an airplane. This too is likely an airline/CAA issue as well as an individual pilot issue. And, not to imply that this is a "third world" country issue as I am seeing this more and more with the FO's I fly with; they are terrified to hand fly the aircraft and hence their hand flying skills begin to decline.

When all of these crews experienced MCAS, 0 of 3 were able to recognize a classic stab trim runaway; while manually flying the aircraft, the nose pitches down all by itself. You simply can't miss it, with or without seeing the stab trim wheel moving. In the Lion Air case where the aircraft was saved, it took a third pilot from a different airline to tell the crew what to do; in the case of the fatal Lion Air accident, the Captain handed control to the First Officer so he could go hunting through the checklist for something to do - this is a memory drill! I fault the individual pilots for not knowing their memory emergencies - harsh as that may sound, that is what we are paid for. (Personally, I do a study of the memory emergencies regularly as the memory isn't what it used to be and I like to think that most professionals pilots do the same).

I am not going to rehash the rest of the issues (flying to destination with this problem, not controlling the aircraft speed in the Ethiopian case, etc) as that would be covering old ground but there are lots of basic airmanship issues that are highly questionable.

In conclusion, all of these MCAS issues were recoverable situations by a trained and competent crew. I do not blame the individuals entirely as the airline, their training, their hand flying policies as well as the CAA overseeing them deserve scrutiny too however. Let me repeat that: These MCAS accidents were all recoverable. Boeing's mistake, in addition to what I noted earlier, is assuming that B737 type rated pilots would be able to do even the most basic, memory emergency drills. This, however, begs the question: If pilots cannot even do a simple UAS emergency, what hope do they have for a more complex one such as an engine failure at rotation or an engine failure followed by a cabin depressurization which that Southwest crew handled masterfully?

What this MCAS situation points to, in my estimation, is that the aviation industry has been "whistling past the graveyard" for a little too long and that the underlying problems quickly manifest themselves with even the slightest irregularity - the Turkish B737 accident at Schipol, the Korean 777 in SFO, etc.. A complete rethink of pilot training, basic flying skills and airmanship are in order as there is a finite limit to what Boeing, Airbus, Embraer or any other aircraft manufacture can do to design and build airplanes without human intervention being required a certain times by competent aviators.
Hello all:
Today I registered for this board although I probably will never post here again. I have lurked for years as I find the topics here of great interest. First, I am not a pilot but a doctorate level engineer who has spent close to 40 years in aerospace design and engineering in the United States.
I am posting today to express my deep appreciation to L39 for his insightful, articulate, and erudite post. In my profession and leisure life I am a (very) frequent flyer. Many of the locations my wife and I travel require one or more 737 flights. I have been following the terrible Max accidents from the initial Lion Air loss, as many of my business and leisure legs have been assigned to 737 Max aircraft. After the second loss I was prepared to find other means rather than board a Max flight, but of course the grounding eliminated the need. Reading every Max related post on this board I must say that I was not encouraged by the tone of many, but not all, of the posts. There seemed to be a widespread feeling expressed among many of the professional pilots that seemed to me as rejection of any thought that the unfortunate crews had any blame in the losses, and that Boeing was to blame completely. The reason that disturbed me so much was that we in the traveling public depend totally on the skill and knowledge of the flight crew. We are totally in your hands. From my background I do understand technically what happened in these accidents and to me, from a technical perspective, it seemed that they should have been recoverable. Despite the challenging human factors environment.
Then finally after 3 months, L39 comes along and tells me exactly what I was looking for in all these posts. If I may repeat your words "....These MCAS accidents were all recoverable......" When I board a flight I need to feel confident that the crew in the cockpit can fly me (and themselves) to our destination safely. After L39's post my confidence is now coming back. I just hope that the confidence and preparation L39 exemplifies is widespread beyond just the people who post here.
Thank you L39 once again.
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