Backtracking on its previous indications, Boeing is now recommending simulator training for 737 MAX crews. In a statement, the company wants “simulator training in addition to computer-based training for all MAX pilots prior to return to service of the 737 MAX. This recommendation takes into account our unstinting commitment to the safe return of service as well as changes to the airplane and test results. Final determination will be established by the regulators.”
“Safety is Boeing’s top priority,” said interim Boeing CEO Greg Smith. “Public, customer and stakeholder confidence in the 737 MAX is critically important to us and with that focus Boeing has decided to recommend MAX simulator training combined with computer-based training for all pilots prior to returning the MAX safely to service.”
Boeing’s largest domestic customer for the MAX, Southwest, had felt that it could bring its crews up to speed with computer training. “That being said, we stand ready to comply with the FAA’s final recommendation and have teams within Southwest that are considering training models for both simulator or computer-based training programs,” Southwest said in a statement to the press. “Since our plans are in the early stages as we await further guidance, we don’t have any time or cost estimates to offer.”
No doubt to stem public fears about the MAX, Boeing has changed tack on the simulator requirement. Making crews a fungible asset across all the recent 737s was a large part of the design process for the MAX itself. Given the fleet size and the number of qualified pilots, it was important for Boeing and its customer airlines to make the transition from earlier 737s to the MAX as seamless and cost-effective as possible.
This request from Boeing and the need to modify existing simulators to emulate the MAX’s handling qualities will likely add to the delays getting the airliner into widespread service. Already, airlines are facing significant effort in taking mothballed aircraft from storage.
Interesting to see how Boeing is slowly stepping off the high horse and starting to realise that skipping some of the proven procedures is costing them an arm and a leg. If they would have gone down that road as a first reaction to the accidents, most likely they would be already flying again.
Reminds me of a child throwing a temper tantrum not wanting to eat the soup and sitting there for two hours spending time on arguing and lots of explaining, while all the other kids are outside playing with each other.
So, how will sim training work?
Scenario one, the pilot flying notices the trim running without his input, how can he tell if this is the normal operation of MCAS, or runaway trim? What happens if he waits too long to decide?
Scenario two, the pilot not flying notices the trim running, how can he tell if this is normal input by the pilot flying, normal input by MCAS, or a runaway trim?
Note, the pilot flying almost always has to run the trim AND (aircraft nose down) after takeoff as speed increases.
Question, when does the pilot flying initiate the runaway trim checklist?
How much time does he have?
What if he hesitates?
How about it Boeing?
Sim training?
I have commented many times before – What kind of sim training is required for a runaway trim???
Some how Boeing should state – “Consider a runaway trim only after x seconds of normal MCAS operation”
C’mon – be realistic – how many take offs do you need to realize what is the NORMAL MCAS operation time!!!
And your take is?
Woah, woah, woah. The issue here is one of UNDESIRED trim movement. If you’re happy with the trim, great. If not, then change it. Depending upon the situation, the (electric) trim may be moving because of:
* Input from EITHER pilot
* Input from the Autopilot
* Input from MCAS
* Input from failed infrastructure (classic runaway trim)
[“Input” here really means “command”]
Regardless, the trim movement is a problem ONLY if it is undesired by the pilot(s).
Yars nailed it! Undesired trim movement and from what source or combination of the four possible sources Yars has proposed.
The confusion for the Lion Air crew came from a combination of all four of Yars potential scenarios contributing undesired trim situations with the added caveat that they had absolutely no knowledge of the then hidden MCAS contribution. During the fatal flight, they managed to get the airplane back to occasional level flight until MCAS took the nose down trim past the physical capabilities of the pilots and the aerodynamics of the airplane to pull out. The number of MCAS activation was incredible. The use of the electric trim was handling the MCAS nose down initiations. Why change what is, for a time, overcoming the repeated nose down inputs. In between MCAS nose down inputs, after apply electric nose up trim, the trim stopped moving, the airplane flew for a few long seconds normally, until the next MCAS activation. The flying pilot had quite a handful and was, for a time, successfully handling the gyrations. Add to this confusion, crew resource issues, conflicting information on both sides of the cockpit, and the conversations with ATC to determine some what accurate speed and altitude information. But the insidious side of this was the increased speed and travel of MCAS activation in the production models vs the initial design and engineering of the prototype MCAS installation. Now add the grossly miss-calibrated AOA.
Interviews with the passengers on the previous flight, whose crew successfully managed the MCAS malfunction, said the pitch movements were so violent it was akin to being on a wild roller coaster ride. The fatal flight profile was more exaggerated than the previous one.
Both Lion Air crews did apply initially successful electric and manual trim actuation combinations. The first crew had less violent issues than the second crew. No one is talking about what actually failed on the previous to the accident flight regarding the MCAS activation. One assumes the AOA failed. But the question is, to what degree. The fatal flight had a grossly miss-calibrated AOA installed within the MCAS system, a system that both maintenance and flight crew did not know existed.
While the Ethiopia crew had somewhat more information, it was more theory than facts. Boeing released the existence of MCAS on board through a customer service letter. Up until the Ethiopian crash, there was no other known MCAS issues plus no clear contributing mechanical cause yet determined in the Lion Air accident. Until the FAA AD came out, Boeing’s way of advising their customers of MCAS on board MAX was through a customer service letter. Had not the FAA issued an AD, it is pure speculation about how long it would take Boeing to advise their MAX customers of the existence of MCAS, how future training would be changed to address its existence, and then handle the firestorm that would be inevitable when it was shown MCAS had a single failure point designed into it. At the time of the Ethiopia crash, there was no Boeing directives for MAX specific training changes nor specific MAX sim time. Handling potential MCAS malfunctions was ambiguous at best. A bunch of people paid the most severe price for that ambiguity.
Up until the second MAX crash, Boeing sold MAX as simply a more efficient, better performing 737 requiring little training changes from previous models thereby minimizing additional training cost. MCAS is the key ingredient in getting the MAX to fly, handle, and behave like previous 737 models. Boeing as far from handling all the consequences of their collective MAX/MCAS decisions. At least there is forced recognition that MAX is a significantly different airplane than its predecessors requiring structured specialized training to address those changes.
In my post above, I said:
“Depending upon the situation, the (electric) trim may be moving because of:
* Input from EITHER pilot
* Input from the Autopilot
* Input from MCAS
* Input from failed infrastructure (classic runaway trim)
[“Input” here really means “command”] ”
Then I went on to say that trim movement (change) is a problem only if/when it is UNDESIRED change. I wanted to keep it brief, addressing only the “how are we supposed to know what the problem is?” issue that was raised by the previous poster.
My larger point is this:
When addressing an instance of UNDESIRED trim change, it really doesn’t matter which one (or which combination) of the four cited sources of trim command is at fault. The solution is to DISABLE electric trim, via one or both of the two switches located at the rear of the center console.
I want to draw a sharp and vital distinction between SOLVING (neutering) a problem, and DIAGNOSING the SOURCE of that problem. In the case of these 737 MAX events, the SOURCE (the nature) of the UNDESIRED trim movement really does NOT matter. Really.
Do NOT conflate SOLVING a problem with DIAGNOSING that problem. Stop the bleeding BEFORE you try to determine what kind of a knife caused the wound!
1. DISABLE the electric trim.
2. FLY the airplane, using the manual trim wheel as required.
3. IF you have the required bandwidth available, diagnose the problem. But not if the diagnostic procedure will compromise the controlability of the aircraft.
In my worthless opinion, MCAS v1.0 is a poorly-conceived pile of something. BUT… ANY competent flight crew should be capable of SOLVING a runaway electric trim situation, without wasting critical time by, instead, attempting (?) to DIAGNOSE the situation.
My annoying lecture is NOT a distinction without a difference. If four pilots had managed to flip four switches, hundreds of dead people would be alive. Perhaps these pilots didn’t know that MCAS existed. Doesn’t matter. They failed to solve an elementary malfunction – runaway pitch trim. So, were back to talking about how best to protect airplanes (and their passengers) FROM pilots. Really.
Well, YARS,
When you said “DISABLE the trim”, that is what I was referring to in my post above – meaning, cut off the trim when it is felt that it is undesired (as you said).
Let’s say you felt that you had a runaway & cut it off.
You then trimmed it manually- then when reengaging the cutoff switches, the trim moved. Of course you have proved there is a malfunction. Solve as you wish. over
If only the two aircrews had disabled the electric trim… as they were trained to do..
The preliminary report of the Ethiopian accident says the flight crew did disable the electric trim. But that was only after a couple of applications of electric nose up trim. By that time, the MCAS had already put in already a substantial nose down trim. The up elevator input to counter the nose down trim put enough load on the trim jackscrew that it was not possible to move the trim wheel manually. The crew then turned the electric trim back on and successfully applied some nose up trim (nowhere near enough). But then MCAS stepped in again and applied a lot more nose down trim. After that it was too late.
The recovery technique the Ethiopian crew failed to apply has been described elsewhere: Fly a roller coaster path – pull like hell on the yoke to get the nose up, then let go of the yoke to unload the trim jackscrew and frantically turn the trim wheel by hand, pull the yoke back again, lather, rinse, repeat until the airplane is stable.
The behavior of the trim system during the failure suggests another strategy: Keep the electric trim on and apply nose up trim until it’s back where it belongs, then IMMEDIATELY disconnect the trim before the spurious nose down trim happens again. I figured this out after looking at the FDR plots for 20 minutes. It’s fair to say that the Ethiopian flight crew didn’t have the time or systems knowledge to make that diagnosis.
“It’s fair to say that the Ethiopian flight crew didn’t have the time or systems knowledge to make that diagnosis.”
It’s also fair to say that the Ethiopian flight crew failed to deal with a pitch trim issue in a timely manner. As I said earlier, the crew did not need to DIAGNOSE (OH, it’s MCAS!) the problem – they needed to SOLVE the problem.