This was not an insulated incident. The modern planes are designed not to crush. It's up to the airlines to make sure that the pilots know and understand the systems. In the Venezuelan crash the pilots rode the plane into the ground from 30 k feet despite the stick shaker. In Brazil, the pilot overpowered the system designed to save the plane after the thrust reverser deployed. It's rare, but it happens. These two will probably be another cases of operators failing to master the type.
Ethiopian Plane Crash
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As jcpro pointed out, not an isolated incident. When Delta and Northwest combined, they discovered over a dozen instances where at least one pitot tube froze. The FAA equivalent in Europe, EASA had 17 reports of pitot tube freezing incidents on the type.
Your opinion differs from BEA's assessment that the crash was due to both human factors and technical problems. In addition to the faulty pitot tubes, the information given to the pilots was confusing and Airbus had to make changes.
Blaming it solely on a pilot is old school thinking dating back to when planes were wood and fabric and was not effective in reducing crashes because there is never one single reason an airliner crashes. Multiple changes need to be made to prevent future occurrences.
As far as MCAS possibly saving AF447, one could also argue if the plane was not so complicated, and had a simple stall horn that only measured angle of attack that couldn't be overridden by parameters decided on by the computer and a physical connection between the two pilot controls, the aircraft may not have crashed.
Automation is a double edged sword in emergency situations.
Pitot tubes as well as any other sensors will occasionally fail. Software systems on things that are in the air travelling at high speed have to be designed to be robust enough to handle occasional erroneous sensor data.
If he only clocked in 200 hours of training with a recommendation of 1500 hrs, this could be a major problem in and of itself.
Retired Commerical Airline Capt. J.P Tristani discussed this with Harris Faulkner today. He believes it is pilot error. I cued the video where his interview starts. He seems to know what's he's talking about
Well of course, I said there were things that messed up the recovery. One of the key ones is the stick shaker being disabled below 70 knots air speed. So when they pointed the nose down and GAINED airspeed the stick shaker activated, without airspeed in an emergency this is a mind fuck. But who would ever imagine an A330 having less then 70 knots airspeed!!! Probably never happened before or since outside testing. Of course it would have been smarter to only do that if the gear is also down. but...hey programmers can be lazy...
The MACS does not activate by pointing the nose down, at least not directly. Upon receiving a high angle of attack signal from an Angle of Attack sensor, it trims the stabilizer downwards. It does not override the pilot's imput of the elevator. But in these 2 cases, there winds up being so much downward stabilizer trim, that there is unsufficient elevator control to prevent an uncontrolled pitch down.
Pilots are trained in all kinds of systems failures. Boeing didn't think it was necessary to train them in case of this occurrence: that of the AoA sensor being faulty and sending a false stall indication to the flight control computer.
This problem was not insurmountable. The day before the LionAir crash, another crew flying the same airplane and experienced the same problem. However, they had the presence of mind to cut the power to the stabilizer trim, as is the procedure for a runaway stabilizer. They weren't specifically trained for that; with proper training, I believe that both accident crews would have reacted appropriately.
One has to be careful when using such layman terms as 'pilot error'. In reality, the pilots screwing up is the final sequence of events that result from poor aircraft design, poor procedures and poor or inadequate initial and recurrent training. Flying a transport category turbojet is not like driving a fucking car.
Airbus 320/330/340 series don't have a stick shaker. There is a synthetic voice warning that says "stall! stall!".
The AF447 crash, although triggered by the freezing up of the pitot tubes, can be attributed to AF's lack of providing pilots with 'airspeed unreliable' training in cruise, plus inadequate crew resources management training. The First Officer, who was in the right seat, was in charge of the airplane when the captain was in the back; he lacked assertiveness when the relief pilot was the pilot flying. Despite the overwhelming number of error messages, he made the right call that they were in alternate law. That meant that there was no stall protection, only stall warning. He should have assertively taken over control from the junior and inexperienced pilot in the left seat. Easier said than done, and one has no idea of the confusion and surprize that must have taken place; but training for this would probably have saved them.
But the news anchor said the Piper Cessna nosedived after the engine stalled. It would be pilot error if he made the fatal mistake of not filing a flight plan.
Absolutely. Did you notice the news anchor bobbing his head as he was saying all that? It means he must have known what he was talking about.
Apparently the found the horizontal stab jackscrew and it indicates the stab was in full nose down position. Poor fuckers did not stand a chance. Question still remains why they did not disable MCAS, but I suspect they were not very high, going very fast due to unreliable speed indication and MCAS nosed them down before they could react. At full nose down position at 400 knots 1000 feet above terrain, that's gonna happen VERY quickly.
I take at face value your technical information.
It is still a simple case of faulty software. For an airplane flying close to the ground as in takeoff, it is not a viable solution to any problem to point the nose towards the ground.. A software (AI) system that does that is faulty, and does not have the appropriate checks on what situation the airplane find itself in.
Early indications are that the cause of both crashes were caused by the MCAS.
I'm all in favor of progress but sometimes the more "stuff" we install on machines the higher the possibility that something will go haywire. KISS (keep it simple, smart).
https://www.cnbc.com/2019/03/18/us-...-of-boeing-737-max-planes-in-crashes-wsj.html
I'm all in favor of progress but sometimes the more "stuff" we install on machines the higher the possibility that something will go haywire. KISS (keep it simple, smart).
https://www.cnbc.com/2019/03/18/us-...-of-boeing-737-max-planes-in-crashes-wsj.html
The Wall Street Journal is reporting that the pilots of the doomed Ethiopian Airlines flight did in fact initially follow Boeing's new instructions on how to disable the MCAS.
Still could not regain control of the plane.
https://www.wsj.com/articles/ethiop...y-steps-to-disable-737-max-system-11554263276
Still could not regain control of the plane.
https://www.wsj.com/articles/ethiop...y-steps-to-disable-737-max-system-11554263276
Yup the disabled it, but were travelling too fast to overcome the trim, and manual trim is not possible at the speeds they were travelling. They were out of time, and altitude, throttleing back at that point would have been too late, maybe speed brakes, and pull back on the yoke for life, in either case, they flew by the book and they all died. This plane is dangrous, I suspect it cannot be fixed without major redesign. Its Boeing Comet moment.
