Boeing 737 Max8 Aircraft Crashes and Investigations [Part 2] 44

[Alistair_Heaton]

This thread is a continuation of:

thread815-445840


****************************
Another 737 max has crashed during departure in Ethiopia.

To note the data in the picture is intally ground 0 then when airborne is GPS altitude above MSL. The airport is extremely high.

The debris is extremely compact and the fuel burned, they reckon it was 400knts plus when it hit the ground.

Here is the radar24 data pulled from there local site.

It's already being discussed if was another AoA issue with the MCAS system for stall protection.

I will let you make your own conclusions.

 

[VEBill]

"...when the first plane [crashed] in Indonesia."

That's a very important point. The whole Air Incident Investigation process is not supposed to require two examples to react.

Perhaps it's 'merely' a timing issue. But that's still a problem if the durations embedded in the processes allows further incidents before corrective actions can be rolled out.

It seems that the investigative and corrective actions process itself should be subjected to a higher level of review.

This point will become self-evident when the two individual reports inevitably cross reference each other's incident.

 

[IRstuff]

There's a corollary thread on this subject on this site here: thread2-451013

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

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[RolMec]

If those jets shall be made to fly again, patched / fixed:
How will the work environment look like for the pilots now?
- always hyper-alert, both of them, to what the plane is doing, or not, or might be cooking up in some software or other
- never sure what card the "system" will play in 5 seconds, fully aware that there's 30 or 40 sec at most, maybe...
- flying a plane which shall behave quite differently once the feature simulating a NG-plane has been cut off.
What a wearsome environment.. and shall they all manage if an emergency comes up.. all those pilots, all of them, not just only some cracks?

And also: how will the travel environment for the passengers look like, feel like, now?

This will be a test to human ability for enduring the unacceptable. But it must not be like that.
Honest and responsable engineering could be done, even now. Full scale test flights could be required, under external supervision.
And a fully open design discussion, including the pilots. Who have a right to get a full scale training to that NEW plane.
No more "Grandfathering".


Roland Heilmann

 

[SwinnyGG]

If those jets shall be made to fly again, patched / fixed:
How will the work environment look like for the pilots now?
- always hyper-alert, both of them, to what the plane is doing, or not, or might be cooking up in some software or other
- never sure what card the "system" will play in 5 seconds, fully aware that there's 30 or 40 sec at most, maybe...
- flying a plane which shall behave quite differently once the feature simulating a NG-plane has been cut off.

The nature of a "fix" is that the problem is fixed. That's the point.

I would think that a properly engineered, vetted, and implemented fix to this problem would be a stress-reducing situation for 737 Max pilots, not a stress-inducing one. Although I can't speak for them, let's not forget that since the Lion Air crash pilots have been whirring around in these aircraft for quite some time, without knowing if a fix for the perceived problem was coming.

 

[saikee119]

jgKRI is correct.

The 40 sec window to rescue the plane is the original MCAS setting. All grounded planes should have it as standard.

Boeing's new patch is supposed to address this risk. Boeing is persuading the aviation companies and the regulators if the patch were implemented it would be safe for Max to return to service.

The MCAS has been designed to trim the plane to nosedive 2.5 degree each time for about 10 sec and then rest for 5 sec. In the original setting MCAS is allowed to activate unlimited number of times( see graph below for the 20+ times in the doomed Indonesian plane recordings). So it takes about 3 activations and the horizontal stabilizer could be at its limit. In the presentation released by Indonesian Aviation Authority KNKT the blackbox data shows pitch trim position was advanced by 5 degrees before the plane impact. According to the explanation by the experts the 1st graph represents the manual trim by the pilot while the 3rd graphs by the MCAS response and the 2nd graph is the pitch trim position.

The new setting permits MCAS to activate only as a once-only event at a time and to take reading from two instead of just one AoA sensor.

MCAS was triggered by a defective AoA sensor in the Indonesian plane. No information is available from the Ethiopian accident yet (due this week). Thus many Max flew without incidents in the USA because the planes did not have fault with the AoA sensors. In any case the MCAS can be disabled by a kill switch if any 737 pilot equates its effect as a standard runaway trim. That was FAA's defense used in the Senate hearings yesterday.

The problem with MCAS is it was not described in the flight manual. It has been pointed out that the name MCAS appears only once in the glossary of terms. Many believe the motive of not mentioning MCAS is if Boeing were to describe it then the aviation company would have to train the pilot to use or cope with it and that costs money. The Max was sold on its claim of minimum training requirement, reported around 1 to 2 hours, needed for a pilot to switch from the older 737 to fly it.

 

[RVAmeche]

It's definitely shady to me that Boeing appears to have tried to "hide" MCAS to minimize training and not re-classify the plane.

But that aside, I'd like to know if their simulator with MCAS ever showed anything like the Lion Air accident happening. If not, why? And if not, how do we know their software patch or whatever will fix the cause, aside from allowing/informing pilots how to disable it.

 

[Compositepro]

As an aerospace materials supplier, I cannot tell you how many times I have heard the statement:
"Fix the problem, but do not change anything."

In the end the problem get's fixed in the manner that can best best be described as "did not change anything significant". But this is usually done by consensus of a group of interested parties.

 

[SwinnyGG]

As an aerospace materials supplier, I cannot tell you how many times I have heard the statement:
"Fix the problem, but do not change anything."

On a similar wavelength- I've been curious throughout the discussion how involved major airline personnel have been/are currently with Boeing's decisions through the development process.

Certainly Boeing is ultimately responsible for the quality and safety of engineering on their products, and programs such as the development of the 737 Max are aimed at growing market share- but the airlines are the ones who stand to gain the most from higher efficiency aircraft, and the most to lose should they be required to adopt expensive training programs to modernize their fleets... When you're Southwest or United or whomever and you're placing product orders in the tens of billions of dollars, I have to think there's a relatively high level of involvement. These aren't housewives buying toasters at Wal-mart.

I'm not attempting to place any blame on the airlines themselves- just curious if it is a realistic thought that a situation like this may not have been a surprise to people at Southwest or Lion Air et. al.

 

[itsmoked]

jgKRI; I can easily see the airlines as being in on this.

"We really like everything about the new MAX series and would probably sign up for 35 of them except the training cost of more than 3 hours is a real problem. Is there nothing you can do in this regard to help me secure this order for Boeing?"

Keith Cress
kcress -

http://www.flaminsystems.com

 

[BridgeSmith]

Given the pricetag of planes themselves, and the savings in fuel costs that they're anticipating, it seems odd that a purchaser would balk at cost of a few more hours of training for the pilots, but hey I don't buy the planes for an airline, maybe it's big deal to those who do.

 

[itsmoked]

Possibly the required updates to everyone's simulators too. I'm sure there was a lot of pressure everywhere to shoe-horn this function in. (I'm not saying it was smart not to!)

Keith Cress
kcress -

http://www.flaminsystems.com

 

[waross]

Lesson learned from the Pinto disaster;
Even if you know better, don't write a memo to upper management suggesting that this is a really bad idea.


Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[IRstuff]

I've written such Pearl Harbor memos and came within a hair's breadth away from getting fired over it; it depends on where you are in the hierarchy.

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[GregLocock]

Fact check: the Pinto memo wasn't about the Pinto. It was an analysis of a hypothetical case in response to a proposed new law.

Cheers

Greg Locock


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[Sparweb]

...it seems odd that a purchaser would balk at cost of a few more hours of training for the pilots...

Are we comparing Boeing's 737NG-to-737MAX transition training (known as "iPad training") against the detailed flight control re-training, which would require hours of simulator time?
Yeah, that's a big bucks issue for airlines. It goes from 100's of dollars per hour to 1000's of dollars per hour training, and take much longer too.

It would also require a whole new subject in the "Abnormal Procedures" of the aircraft flight manual. That becomes a subject for both introductory and re-current training, so the increased costs don't end when the crews are all trained up; the extra procedure is re-tested periodically, again in the simulator.


No one believes the theory except the one who developed it. Everyone believes the experiment except the one who ran it.
STF

 

[waross]

How much would an 8% saving in fuel consumption save in a flight from Calgary to Toronto (1750 miles) or, alternatively, one day in service for 12 hours compared to the cost of retraining the flight crew?

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[RVAmeche]

It would also require a whole new subject in the "Abnormal Procedures" of the aircraft flight manual. That becomes a subject for both introductory and re-current training, so the increased costs don't end when the crews are all trained up; the extra procedure is re-tested periodically, again in the simulator.

Which may have saved 300+ lives. No biggie...

 

[BridgeSmith]

If I read correctly, each plane is $27 Million. Compared to that, yes, even several thousand $ multiplied by half a dozen pilots per aircraft would have been a paltry investment. Of course, as RVAmeche noted, the 300+ lives needlessly lost is not insignificant either. Add to that, the loss of trust by both pilots and passengers, and indeed a Million $ or more for training would have been easily the cheaper option.

 

[Sparweb]

8% saving in fuel consumption save in a flight from Calgary to Toronto (1750 miles)

Wayyy bigger than the training cost. But the training cost is on a different line of the balance sheet. Fuel is paid for by operating revenue. Training is overhead. Doing your training in a simulator is awesome, but it costs 100X more than reading operations manuals. When the margin on your bottom line is as thin as the airlines have it, a few hours of time in the simulator is yet another cost hump to overcome.

Guys,
I'm not defending evil. I'm just analyzing where it comes from. Since you asked.

Step back, and don't look at the cost of simulator training any more: consider what it "mean" instead. If your pilot can read an operations manual to transition to another aircraft type, then that's one more piece of evidence that it's not a big change in the aircraft type design. If instead that pilot must spend hours in a simulator to adapt to new procedures in that aircraft, that speaks to a much larger scope of the change. Boeing's goal is to minimize the perceived scope of the change to the aircraft model with the new engines. If they let the scope creep, they will have to step up the certification basis to newer rules. Boeing's goal was clearly to avoid this at all cost - the certification basis of the 737 is from the 1960's!

The cost of training is therefore just a symptom of Boeing's desire to maintain the 737's in the same certification standards.

No one believes the theory except the one who developed it. Everyone believes the experiment except the one who ran it.
STF

 

[waross]

Thanks SparWeb.
"Wayyy bigger than the training cost."
I suspected that. It's nice to have it confirmed.

The cost of training is therefore just a symptom of Boeing's desire to maintain the 737's in the same certification standards.

Now that both Boeing and the FAA may have lost credibility internationally, FAA type certification may be the least of their worries.

Bill
--------------------
"Why not the best?"
Jimmy Carter