Originally Posted by
737mgm
Almost 5000 posts later it is clear it doesn't matter what professional 737 pilots will say about this issue. You guys have made up your mind and no facts will get in the way of that opinion. Nonetheless I will give it another try even though what I am about to write has probably already been mentioned several times:
The MCAS system obviously should have been designed better but the press makes it seem as if Boeing knew the system created great risks but they went ahead with it anyway in order to make more profit. That thought in itself is so absurd that arguing with anyone who believes it, is basically pointless. If Boeing had thought these accidents were likely to occur they would have designed the system differently.
What does this MCAS monster as you call it actually do? It lowers the nose of the aircraft by changing the position of the horizontal stabilizer. It doesn't make the wings fall off, it doesn't set the plane on fire... it only moves the horizontal stabilizer. There is a switch on the pilots control column which moves the horizontal stabilizer and it overrides MCAS each time. I know you guys do not want to face it, but it really is that simple. Now if someone is reading this, thinking if it was that simple why didn't the pilots just do it? First of all they did. The Lion Air Captain did it at least twenty times. And the Ethiopian Captain did trim out the MCAS induced movement completely the second time it activated. So we could already talk a lot about why they didn't do it the whole time, then lower the flaps for landing (MCAS deactivates) and land. Aside from the fact that they did use the trim switch a little bit at least. please have a look at Asiana flight 214, Emirates 521, or Turkish 1951. These are only a few examples of flights were pilots failed to do the most basic thing: flying the aircraft. There were other causes as well and in the case of Turkish and Asiana the flights were not stabilized at 1000 Feet which means they should have carried out a go around preventing both accidents even before the mistake of not flying the aircraft (speed control) was made.
What these accidents show you is that pilots will crash aircraft even though it would have been very easy not to. In the case of Asiana and Emirates there were not even any system failures. Why these things happen is a completely different issue and the answers are to be found in the human factors involved when people fly aircraft. The Fact is, planes crash because pilots do not carry out the basic steps involved in flying an aircraft.
Now one important point I would like to make to all the posters with their Skygod and hindsight comments: First of all, it isn't about blaming the pilots. It is about stating facts. If I or others state that the crew did not carry out the unreliable airspeed memory items when in fact Boeing requires a crew to so in the situation they were in, then that is stating a fact and has nothing to do with hindsight or blame. Stick shaker only on one side, several caution lights going on, differing airspeed indications create a very confusing situation. For exactly that reason there are memory items in order to deal with that situation and they must be carried out. This procedure is a life saver because in that situation it is nearly impossible to figure out which system is malfunctioning and what is actually going on. For that reason: AP off, AT off, FD both off, flaps extended 10° pitch 80% N1. This will set the airplane on a safe flight path and you will continue to climb away from the ground. Now you have time to figure out the problem. This is what we are trained for. This is our job. Carrying out these procedures in that situation has nothing to do with being a skygod and pointing out that the crew did not do it doesn't make us armchair pilots with hindsight. If there is an engine fire on take off I carry out my memory items, if there is a rapid depressurization I carry out my memory items. Again this is what we are trained for.
If the crew had done this on any of these flights we wouldn't even be talking about MCAS. I am not blaming the crew when I say they did no do this. The crew is always just a product of the training department and the general procedures of the airline they fly for. For example, in the case of the Emirates crash, the crew wanted to fly a go around. They only pushed the take off/go around button but did not actually move the thrust lever forward in order to increase thrust on the engines. These pilots were not idiots. I can completely understand how this could happen. Normally as long as the automatic thrust control is engaged, pushing the TOGA button will increase thrust. However, shortly after touch down the automatic thrust control is automatically disengaged. Emirates is an airline with procedures that will not allow pilots to fly manually with the flight directors off for example. I can understand how a crew that is trained to rely on automation will not think to actually move the thrust levers and will not check if the thrust is increasing, despite procedures to do so. Basic skills are lost if one does not use them regularly.
The 737 MAX is grounded and will continue to be grounded for a long time because people think the airplane is unsafe. Furthermore the press reported the Ethiopian pilots carried out all the required procedures and yet they crashed. Why are people like me writing on this forum? It simply isn't true that the 737 MAX is inherently unsafe even with the "old" MCAS and it isn't true that the crew carried out the required procedures. That is not my opinion. That is a fact (again why they did not do it is another issue). If the established procedures had been carried out the planes would not have crashed. There was not one procedure done wrong but several done wrong. Each one of these procedures would have saved the aircraft. Carrying out the unreliable airspeed memory items is one procedure. If the pilots do not do this they are already entering an area where they are not flying the airplane according to procedure anymore but even in that case, carrying out the stab trim runaway memory items correctly once MCAS engaged (please stop these ridiculous comments that the MCAS activation cannot be recognized as a stab trim runaway) would also have saved the plane. If the pilots decide for whatever reason to not even do that, they still have the option of just trimming out the control forces each time MCAS activates (basic flying skills). Again when I am stating what they should have done according to procedure I am not blaming the pilots but only stating the facts of what Boeing says pilots must do in these situations and what we are trained for in our manuals and in the simulator. These recommended procedures would have saved the plane and please realize that there was a flight that had exactly the same problems and they did land safely (and they did not carry out unreliable airspeed mem items and also did not accurately carry out the stab trim mem items and still they saved the plane proving there are several options and it is not a react quickly or die situation).
Final comment: In my opinion crews that are not trained well and are lacking basic skills of flying the aircraft due to company policies are a far greater threat to aviation safety than any system design. I believe we still have a long way to go until we will design systems that never fail (if ever). So it will continue to be up to the pilots to save the day when systems malfunction. There needs to be a focus on enabling pilots to do so a lot more than focusing on how MCAS can be improved.
After what 5000 posts - can you answer why :- At 05:42:54 - Both pilots call out "left alpha vane"
This is 4 minutes and 12 seconds after WOW (take off) and they did not have the AoA disagree option I believe - pretty strange for a reasonable time Captain and low total time cadet to have a "snap" on exact words at that stage of flight.