[Rockin Robbins]

Originally Posted by Catfish

Well as far as i read the trimming automatics came on after being put to off position, this video does not mention one word of this.

The words "the pilots repeatedly followed procedures by Boeing and MCAS continued to turn back on" came from the airline, not the Preliminary Accident Report, which says no such thing. Who made up that whopper, of course, is unknown.

Originally Posted by Catfish

https://leehamnews.com/2018/11/14/bo...to-the-pilots/
"It’s probably this counterintuitive characteristic, which goes against what has been trained many times in the simulator for unwanted autopilot trim or manual trim runaway, which has confused the pilots of JT610. They learned that holding against the trim stopped the nose down, and then they could take action, like counter-trimming or outright CUTOUT the trim servo. But it didn’t. After a 10 second trim to a 2.5° nose down stabilizer position, the trimming started again despite the Pilots pulling against it. The faulty high AOA signal was still present."

Again, facts ONLY come from the Preliminary Accident Report, not the malfunctioning news media. Several statements in this so-called news report are completely false. "It’s probably this counterintuitive characteristic, which goes against what has been trained many times in the simulator for unwanted autopilot trim or manual trim runaway, which has confused the pilots of JT610." is entirely wrong. The memory procedure for dealing with trim overrun was written before April of 1967 and has been in continuous use since then. MCAS is only one of several possible causes of routine trim overrun malfunction. This is a routine malfunction to be handled routinely. See the Preliminary Accident Report for complete verification.

Originally Posted by Catfish

"How should they know that pulling on the Yoke didn’t stop the trim? It was described nowhere; neither in the aircraft’s manual, the AFM, nor in the Pilot’s manual, the FCOM. This has created strong reactions from airlines with the 737 MAX on the flight line and their Pilots. They have learned the NG and the MAX flies the same. They fly them interchangeably during the week.
They do fly the same as long as no fault appears. Then there are differences, and the Pilots should have been informed about the differences."

Again for a complete and thorough treatment of MCAS and electric trim behavior see the Flight Operations Manual section of the Preliminary Accident Report. Pilots knew that pulling on the yoke would never influence the trim system in any way. This has been true for 52 years and nobody in three generations has been concerned about that. The trim system memory procedures are identical for all flavors of 737 and are a memory procedure. Prospective pilots must demonstrate that they know from memory, without reference to a manual, how to deal with this problem. It's a routine, straightforward 100% effective way to deal with any electric trim system overrun, no matter how it's caused, by MCAS or any one of dozens of other possibilities. The MAX flies identically and the procedures for trim overrun are identical to all 737 series.

Originally Posted by Catfish

Despite some omissions he also clearly states that this runaway trim was not able to overcome manually with the trim wheels due to the load on the elevators.

They were unable to manually trim the aircraft because they were flying it more than twice the maximum operating velocity of the aircraft, not because MCAS was fighting them.

Originally Posted by Catfish

But you do not take away thrust in a starting condition at a high angle of attack, when your plane's nose goes up and down without being able to control it, and they had two minutes to check it all. Not enough altitude.

They were eight minutes into the flight. Where does two minutes come from. They were at enough altitude that level flight, which they had attained wouldn't result in controlled flight into terrain. Altitude wasn't the emergency.

Originally Posted by Catfish

They were two pilots, not one of them seems to have realized the speed. I can only imagine howit is with a runaway stabilizer, warnings blaring and then adding another one with overspeed.
https://www.flightglobal.com/news/ar...runawa-453443/
" ... in the case of the Lion Air Boeing 737 MAX crash, “now the airplane is pitching down and actually moving the control wheel will not stop that system. If the pilot uses the trim system on the yoke, the [MCAS] system will stop" but "if the airplane isn’t in the proper attitude it will reactivate, ...”

Look at the altitude plot in the Preliminary Accident Report, the ONLY, ONLY source of facts available. At the time the elevator trim override switches were reengaged, the pilot had climbed the airplane to a safe altitude, MCAS was disconnected and unable to influence trim any longer. There WAS NO runaway stabilizer. The co-pilot had saved the airplane. That's when the pilot violated protocol, reengaged the electric trim system and handed control back to MCAS, which he knew would immediately crash the airplane. He put MCAS back in control, regained neutral trim and then let MCAS crash the plane. Pilot error.

"Two minutes sounds like much time and mybe for a fighter pilot it is, but.."[quote] But they had more than 8 minutes to fix it. They did and still found a way to crash the plane.

Originally Posted by Catfish

Maybe it was a 'pilot error', or an unlucky combination of changed 737's properties and the pilot(s) (both of them!) knowledge, but in any case it is not a good idea to use several automatic systems fighting each other, and overloading the pilot with figuring it all out and requiring inputs to correct faulty sensors.
I do not like Airbus for exactly this reason. Taking control away from pilots is seldomly a good idea when there is a real problem.

Several systems were not fighting each other here. Airbus killed more people with a plane that actually malfunctioned, removing control of all functions from the crew, which was left with no possible control of the aircraft.

You're totally correct. New emphasis in manual control of aircraft, proper instrument scan routines, seat of the pants flying needs to be done, especially in third world countries. Total dependence on automatic systems is sure death. This incident totally proves that, but the total dependence doesn't reflect on Boeing, it reflects on the airlines, probably even American airlines, and the individual pilots who don't seek to actually know how to fly. They merely monitor automatic systems and watch the crash from especially close up when the automatic systems fail. And they WILL fail sometimes.