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OldB747Driver
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Tue Feb 16, 2021 3:31 pm

Zeke wrote:
Someone needs to defend those who are not here to defend themselves.

Having arrived at that conclusion, I assume it wouldn't do any good to ask you to review my posts on the topic.

I suspect I understand which nerve I hit to make you respond in this manner, so I won't prolong it further, but suffice it to say I hold the "system" itself responsible as much as actions of the crew.
 
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zeke
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Tue Feb 16, 2021 3:49 pm

OldB747Driver wrote:
Zeke wrote:
Someone needs to defend those who are not here to defend themselves.

Having arrived at that conclusion, I assume it wouldn't do any good to ask you to review my posts on the topic.

I suspect I understand which nerve I hit to make you respond in this manner, so I won't prolong it further, but suffice it to say I hold the "system" itself responsible as much as actions of the crew.


No, you have brought the reputations of those who,lost their lives into disrepute without having the facts at hand. I have followed this accident very closely performing a lot of background analysis and have shared that with others privately before this report was published. The data has a forensic fingerprint, I was right on the money. I fail to see how any competent crew would have walked away from this as low as they were.

Between the two pilots they had something like 23,000 hrs on 737s, their longest sectors would probably be 2-3 hrs, with many shorter sectors. They would normally be doing 4 plus sectors a day.

These pilots were not a slave to automation, they didn’t even engage the autopilot until around 2000 ft according to the report.

They are flying in a part of the world that sees significant fires, significant storms, significant volcanic activity, crap ATC, they survive years of that and don’t survive an autopilot tripping off.

As an academic exercise, have a look how many days the 737 classics have been flying in Indonesia since the accident. What does that information tend to indicate.
“Don't be a show-off. Never be too proud to turn back. There are old pilots and bold pilots, but no old, bold pilots.” E. Hamilton Lee, 1949
 
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par13del
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Tue Feb 16, 2021 4:21 pm

zeke wrote:
As an academic exercise, have a look how many days the 737 classics have been flying in Indonesia since the accident. What does that information tend to indicate.

...could be somewhat confusing, on one hand we can say that an old jurrasic 737 with little to no automation 2 axis autopilot has been flying safely in the region, on the other hand we can say the lack of automation no 3 axis autopilot in the jurrasic 737 is what caused this crash...so a da*** if you do dam*** if you don't type situation.
 
bennett123
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Tue Feb 16, 2021 4:26 pm

zeke wrote:
CrewBunk wrote:
And that brings up another point, if you let the asymmetry get so bad that the autopilot is about to kick off, it does give you a very obvious warning. The yoke will be at its full deflection as the autopilot is trying to use roll to counteract yaw. You’d have to be blind to miss that. In fact, I used that yoke deflection as a way of seeing how well I was doing at keeping things trimmed.


I linked a report earlier of a 737 report in Japan where a pilot inadvertently moved the rudder trim instead of the door open and caused an upset. They looked at the human factors of the control column displacement as you have described and didn’t conclude it was particularly obvious.

Exeiowa wrote:
Can someone who understands the reading between the lines part of the report explain what was going on with the thrust asymmetry problem. As I know nothing about the mechanics of the system, what information the pilots are presented with and what information can we infer that it not spelled out. I feel like I am watching a scene through a peep hole where I cannot see everything at once but the rest of the people observing have a less obstructed view.


My guess would be one servo driving the right throttle had failed. I think the left throttle was reducing in response to the level off at 11,000 ft. The left side had to overcompensate in its reduction so the total thrust would stop the airspeed acceleration.

My guess also due to the destination conditions the captain was the PF on this sector.

Hi Zeke,

Perhaps you can explain the section from 245.652 in layman's terms.

What is the plane doing/being told to do?.


pugman211 wrote:
If the above is true, then when the autopilot disconnected wouldn't the aircraft enter a sharp left turn? But the final seconds show a sharp right turn, which to me looks like pilot intervention, right?


The image below is my own work based off the last 41 seconds of the ADSB data, in that I saw turning rates of greater than 5 degrees per second. My personal opinion is the rolled inverted and the left turn (anticlockwise when viewed from above then becomes a right turn (clockwise). Heading in the FR24 data is off the earths reference frame, not the aircrafts.

Image

airtechy wrote:
The engineer in me would sure like to see a block diagram of the autothrottle system to see how it is implemented. The thrust change required ( I assume based on airspeed error) has to be the split between the two engines, but how is that value acquired and how is it split between the two engines? You would think (?) that there would be a safeguard against such a large difference in commanded thrust from the two engines (such as maybe a look at the N1 gauges). :scratchchin:


I think the thrust was supposed to come back on both sides for the level off at 11000 ft. There is technically no reason you cannot fly with one engine at high thrust and one at idle, this maybe necessary for example if vibration was being experienced on one side. The autopilot however on the 737 cannot gable this automatically, it requires the crew to trim the rudder manually. The undesirable state the autopilot and auto thrust left the aircraft in gave the crew very little time to recover.

The same style of accident would not occur on the newer FBW Boeing’s, their autopilots would use rudder automatically and would not permit a 45 degree AoB.
 
OldB747Driver
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Tue Feb 16, 2021 5:37 pm

It is easy to forget that "Jurassic 737's" were once state of the art and certainly not considered a compromise to safety.

Because we tend to view history in the context of the present (old technology compared to new tech) it is instructive to ask ourselves "What changed?" We went from crashing airplanes due to lack of awareness of our operating environment to crashing airplanes due to lack of awareness of the automated systems.
 
FLYBY72
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Tue Feb 16, 2021 5:47 pm

zeke wrote:
OldB747Driver wrote:
Zeke wrote:
Someone needs to defend those who are not here to defend themselves.

I fail to see how any competent crew would have walked away from this as low as they were..


Because you are only looking at the data the way you want to see it.

They were very vague on certain information and completely left some out.

At 14:40:05 LT, the FDR data recorded the aircraft altitude was about 10,900 feet,
which was the highest altitude recorded in the FDR before the aircraft started its
descent. The AP system then disengaged at that point with a heading of 016, the
pitch angle was about 4.5° nose up, and the aircraft rolled to the left to more than
45°. The thrust lever position of the left engine continued decreasing while the right
engine thrust lever remained.


On several occasions they mention both the left throttle position and N1 decreasing but the right "remained!"

The FDR data also recorded the left engine N1 was
decreasing whereas the right engine N1 remained.

Notice they never say where it remained. It was still at climb thrust, but they leave that out.

When the AP disengaged the plane did not "flick roll" as you put it. They say the "aircraft rolled to 45 degrees" That would easily have been caused by having 1 throttle at climb power and the other at idle.

They also do not say when the crew eventually brought the right throttle to idle. Why not? They have that data, but they didn't release it.

At 14:40:10 LT, the FDR data recorded the autothrottle (A/T) system disengaged and
the pitch angle was more than 10° nose down. [b]About 20 seconds later the FDR
stopped recording.
The last aircraft coordinate recorded was 5°57'56.21" S
106°34'24.86"

What happened in those last 20 seconds?
Last edited by FLYBY72 on Tue Feb 16, 2021 5:53 pm, edited 1 time in total.
 
WIederling
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Tue Feb 16, 2021 6:10 pm

OldB747Driver wrote:
It is easy to forget that "Jurassic 737's" were once state of the art and certainly not considered a compromise to safety.
addition by me wrote:
...for the late 1960ties environment.


Because we tend to view history in the context of the present (old technology compared to new tech) it is instructive to ask ourselves "What changed?" We went from crashing airplanes due to lack of awareness of our operating environment to crashing airplanes due to lack of awareness of the automated systems.


You omit that the number of crashes has contracted strongly with time gone by.

The number of "automated" crashes is microscopic to the number of crashes
produced by those allegedly super proficient, better than 2020 pilots ever can be "iron ass" flyers back when.
Murphy is an optimist
 
OldB747Driver
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Tue Feb 16, 2021 6:35 pm

WIederling wrote:
You omit that the number of crashes has contracted strongly with time gone by.

I wrote:
Without a doubt automation has made the industry safer. It is, indeed, difficult to ascertain to what degree mechanical reliability, regulation, training (a rather broad grouping) and so on have contributed to that, but automation certainly has it place among the major factors. But from my perspective, the trend in much of the industry is to allow automation to supplant the development of essential skills so airlines can reduce the pilot to a basic commodity just like fuel and oil. Pilot shortage? Solution: Dog and a pilot: pilot engages the autopilot, dog bites pilot if s/he tries to disengage autopilot.

WIederling wrote:
The number of "automated" crashes is microscopic to the number of crashes
produced by those allegedly super proficient, better than 2020 pilots ever can be "iron ass" flyers back when.

I do not disagree, but the trend we are seeing are events occurring in physically sound airplanes and the automation has an adverse role in those events.

The 'blowback' to my statements seems to be centering around those who believe automation makes up for inexperience, which I think the trend is proving to be incorrect. It's not that us old pilots are intrinsically better than either of the two pilots of SJ182 (we are human too) - only that we have "been there, done that" and the culmination of those experiences would have more likely made an "old iron ass" disconnect that autopilot when it no longer was turning toward the desired heading well before things came unglued. Speculation, yes, but not a stretch at all.

This old iron ass avoided god only knows how many potential issues by disconnecting the autopilot FIRST and asking questions LATER. That mindset ("experience") is apparently going the way of the dodo as we become more automation dependent.
 
Exeiowa
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Tue Feb 16, 2021 6:38 pm

I think it is less productive looking to find blame and better to help people succeed. The recent crashes have highlighted the problem of automation/human interface. Where situations that were solvable or avoidable by the pilots were not because that interface broke down, be it insufficient information about a system, being dumped into an unstable position without knowing what it occurring. Looking for individual extenuating circumstances is not as useful as improving this. Adding more alarms is not useful providing better alarms is what would help.
 
OldB747Driver
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Tue Feb 16, 2021 7:03 pm

Exeiowa wrote:
I think it is less productive looking to find blame and better to help people succeed. The recent crashes have highlighted the problem of automation/human interface. Where situations that were solvable or avoidable by the pilots were not because that interface broke down, be it insufficient information about a system, being dumped into an unstable position without knowing what it occurring. Looking for individual extenuating circumstances is not as useful as improving this. Adding more alarms is not useful providing better alarms is what would help.


Amen. But for now, there still is no replacement for an experienced pilot.
Last edited by OldB747Driver on Tue Feb 16, 2021 7:06 pm, edited 1 time in total.
 
WIederling
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Tue Feb 16, 2021 7:05 pm

OldB747Driver wrote:
This old iron ass avoided god only knows how many potential issues by disconnecting the autopilot FIRST and asking questions LATER. That mindset ("experience") is apparently going the way of the dodo as we become more automation dependent.


I probably was a bit "pointy" with my post.

Blowback:
IMU the chances of getting in contact with the "learning innoculations" you talk about is going down fast.
( I do see and understand "your" mechanism and how it works! )

In the final end the pilot may well sit with the paxes :-)

100k hours of experience with no chance to get that experience ( we only let you fly after you've done those 100k hours of flying .. :-)
is a chicken and egg problem that gets solved by removing both chicken and egg.

Another run off is learning by watching/replicating vs learning by getting schooled inside a well designed program.
Murphy is an optimist
 
OldB747Driver
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Tue Feb 16, 2021 7:12 pm

WIederling wrote:
I probably was a bit "pointy" with my post.

No offense taken, honestly. Appreciate the debate and food for thought.
 
airtechy
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Wed Feb 17, 2021 1:11 am

wjcandee wrote:
GalaxyFlyer wrote:
BEFORE any of those cues, your back should tell you there’s a lot of yaw be applied to the plane. Yes, you can tell some thing wrong by the feel of the plane, the sounds or in the seat of your pants.


Especially with a lot of hours in-type, as this captain had.

Compare to that Ameristar MD80 captain with a zabillion DC9 hours who aborted the takeoff after V1 because when he pulled back on the yoke and the nose didn't rise and he pulled further and it still didn't rise, he "knew it wasn't gonna fly". The aircraft, with a college basketball team aboard, overran the runway and it was a miracle nobody was killed. The captain took massive abuse in the press and from "experts" consulted by the press for aborting after V1, until nearly a year later when the NTSB not only cleared him, but in their report complimented him on quickly taking the correct action even though it was contrary to the norms. His experience told him it wasn't gonna fly, and the NTSB concluded that there was no way it was ever gonna fly, and likely if he had continued to try to take off for even another couple of seconds, the accident would likely have been Very Bad. That's kind of the way it's supposed to work. Sadly for the Sriwijaya Air crew, this time it didn't.

More info: https://www.ntsb.gov/news/press-release ... 90307.aspx
https://www.planeandpilotmag.com/articl ... 116-lives/


That's an extremely interesting report. Thanks for posting. An accident that at first had an obvious "cause" which turned out not to be so obvious after all. The pilot aborted past V1 what seemed by all instrument indications to be a normal takeoff and the check airman was smart enough not to counter his abort. The investigation showed that the plane was incapable of flying and under a normal preflight the failure could not be detected prior to rotation on takeoff.

Re: training. You will never be able to train for every possible automation failure that may be encountered as machinery and electronics either singly or in combination can and will fail in ways that were not anticipated. Maybe we should divert a bigger part of the training regiment away from how to use the automation and into how to recognize when it has failed and turn it off. I don't think there is any civilian airplane that "requires" the automation to stay aloft.
 
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zeke
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Wed Feb 17, 2021 2:35 am

FLYBY72 wrote:
Because you are only looking at the data the way you want to see it.

They were very vague on certain information and completely left some out.


I have posted additional data on this thread from the raw ADS-B data.

FLYBY72 wrote:
When the AP disengaged the plane did not "flick roll" as you put it.


That is what the ADS-B data shows, the initial upset started with a 8 degree heading change in 0.156 seconds, (which is a rate of 52 degrees per second). The change in headings and altitudes and rate of change can and were calculated by me between ADS-B data points.

FLYBY72 wrote:
They say the "aircraft rolled to 45 degrees" That would easily have been caused by having 1 throttle at climb power and the other at idle.


That is partially the cause, the main cause is the autopilot would have been making significant roll input to counter the yaw and to turn onto the requested heading of 075, and that roll input is neutralised when the autopilot disconnected. So the sudden removal of the aileron input is equivalent to a sudden roll input at 270 kts., the ADB-B data shows corresponding high turn rates.

FLYBY72 wrote:
They also do not say when the crew eventually brought the right throttle to idle. Why not? They have that data, but they didn't release it.


They have that data and it was in the draft of the preliminary report, and subsequently removed before publication.

FLYBY72 wrote:
The last aircraft coordinate recorded was 5°57'56.21" S 106°34'24.86"


That wasn’t the last point transmitted, the last ASD-B point transmitted is just 78 meters from the main underwater debris field.

FLYBY72 wrote:
What happened in those last 20 seconds?


I have posted the ADS-B data for the last 40 seconds on this thread, you can see for yourself, look at the headings and the elapsed time between points.

Image
“Don't be a show-off. Never be too proud to turn back. There are old pilots and bold pilots, but no old, bold pilots.” E. Hamilton Lee, 1949
 
wjcandee
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Wed Feb 17, 2021 3:23 am

airtechy wrote:
That's an extremely interesting report. Thanks for posting. An accident that at first had an obvious "cause" which turned out not to be so obvious after all. The pilot aborted past V1 what seemed by all instrument indications to be a normal takeoff and the check airman was smart enough not to counter his abort. The investigation showed that the plane was incapable of flying and under a normal preflight the failure could not be detected prior to rotation on takeoff.


I went back and reread pages 53 and 54 of the actual report, which discuss the propriety of the aborted takeoff. The wording is remarkable, I think, in that it shows extraordinary empathy for the Captain by the NTSB. Doubtless they were aware of the drubbing that he received after the accident. The NTSB also addresses the "they took off in high winds when they shouldn't have" allegation in other parts of the report, and clears the crew on that as well. The CVR transcript shows that the crew was keenly-aware of the unusual situation of there being no power or weather report at the airport, and that they made sure that they could legally-rely on the weather that the FAA provided from other locations. They seemed to be a very rules-and-safety-focused crew. I think the NTSB makes clear elsewhere that the check airman actually started to reach for the controls, but checked himself, perhaps because he was following the SOP, but by his statement at least in part because he saw that this highly-experienced-in-DC9s captain had already disconnected all the automation and had the reversers deploying the time the check pilot had started to react. Lucky. The check pilot does let off a number of expletives about not aborting after V1 as they're mashing on the brakes. What is always remarkable to me about the CVRs in runway overruns is how much time the crew has to contemplate and remark upon an impending sequence of events over which they now have limited control, like the Southwest captain who was telling his FO, "My fault, my fault, my fault" as they were going off the end of the runway, through the fence, and into the gas station. Those few seconds are the stuff of nightmares.

Anyway, when that report came out, I thought it was a memorable one, and it's always nice to see the good guys get the accolades they deserve.
 
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SomebodyInTLS
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Wed Feb 17, 2021 9:55 am

WIederling wrote:
OldB747Driver wrote:
It is easy to forget that "Jurassic 737's" were once state of the art and certainly not considered a compromise to safety.
addition by me wrote:
...for the late 1960ties environment.


Because we tend to view history in the context of the present (old technology compared to new tech) it is instructive to ask ourselves "What changed?" We went from crashing airplanes due to lack of awareness of our operating environment to crashing airplanes due to lack of awareness of the automated systems.


You omit that the number of crashes has contracted strongly with time gone by.

The number of "automated" crashes is microscopic to the number of crashes
produced by those allegedly super proficient, better than 2020 pilots ever can be "iron ass" flyers back when.


This is something which always seems forgotten whenever this pilot versus automation argument pops up on here (basically every accident with unusual or initially unclear cause).

It's actually because the automation is so good that the very rare failures of it and/or its man-machine interface make headlines and start the argument again. It's ironic that those arguing against automation never see that its very success is what they are discussing.

The more automation improves safety, the more glaring the exceptional failures will seem...
"As with most things related to aircraft design, it's all about the trade-offs and much more nuanced than A.net likes to make out."
 
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par13del
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Wed Feb 17, 2021 2:28 pm

SomebodyInTLS wrote:
It's ironic that those arguing against automation never see that its very success is what they are discussing.
.

Unfortunately, the extremes still dominate the discussion, the positions usually taken is that one is either for 100% full automation or 100% no automation, hence the reason why we have accidents, the engineer mindset is to completely remove the pilot and the pilot mindset is to retain control.
The funny thing in all this is that the poor pilot is still held 100% accountable for signing the release sheet because he / she is the captain in charge.
 
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SomebodyInTLS
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Wed Feb 17, 2021 5:25 pm

par13del wrote:
SomebodyInTLS wrote:
It's ironic that those arguing against automation never see that its very success is what they are discussing.
.

Unfortunately, the extremes still dominate the discussion, the positions usually taken is that one is either for 100% full automation or 100% no automation, hence the reason why we have accidents, the engineer mindset is to completely remove the pilot and the pilot mindset is to retain control.
The funny thing in all this is that the poor pilot is still held 100% accountable for signing the release sheet because he / she is the captain in charge.


Hmm... not totally convinced. I think real engineers are aware it's about minimising risk given a set of circumstances - at the moment those circumstances include keeping pilots in the loop and ultimately responsible... but that's actually a requirement demanded by society!

In this case everything is engineered to make the pilot as in control as they want/need to be while ensuring as far as possible that they are presented clear and relevant information and at the same time preventing any avoidable errors, with some additional safety to help keep things under control when things go wrong.

I think the people likely to believe engineers are 100% anti-pilot are probably those who are fervently pro-pilot... :)

I do believe there will come a time when well-designed pilotless aircraft will in principle prove to be safer than those which are piloted. It does depend on the best fail-safe systems design, of course, which (for now) will still be an opening for human error to creep in. There will come a tipping-point when driverless cars etc. will have proved themselves and society will no longer demand a bum in the front seat.
"As with most things related to aircraft design, it's all about the trade-offs and much more nuanced than A.net likes to make out."
 
WIederling
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Wed Feb 17, 2021 5:39 pm

par13del wrote:
The funny thing in all this is that the poor pilot is still held 100% accountable for signing the release sheet because he / she is the captain in charge.


There is no captain with a fully automatic airplane.
( compare : fully automatic local transit systems.)

in the automobile domain the manufacturers have taken up the liability ( well their promise at the moment).
Murphy is an optimist
 
OldB747Driver
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Wed Feb 17, 2021 8:01 pm

The imperfect humans that make errors in flight operations are the same humans that design (and implement) automation. The main advantage the automation has is that its design is based on MANY human minds but the disadvantage that they ultimately have to base that design upon their best predictions.

The chaotic and unpredictable nature of failure modes are exactly the reason why an intellectually "dynamic" (versatile) human being will always be essential in the functionality of human-designed automation. To the ends of achieving that level of functionality, the ability of a pilot to completely and safely take full control when needed is necessary; combining this requirement with an understanding of human performance results in the requirement for both knowledge and practice, aka "experience", wherewith the greater the experience, the higher the degree of safety.
 
Chemist
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Wed Feb 17, 2021 9:21 pm

It's interesting because the automation has helped improve safety, but when the automation goes south, we have accidents that wouldn't have happened without the automation.
In this accident (as it appears), an autothrottle malfunction went unnoticed by the pilots and caused a crash. But if they had been hand flying at that point this would not have happened. If they had even been hand flying with autothrottles engaged, they probably would have noticed the changing control inputs required to maintain heading and still the accident would not have occurred. The fact that less attention is required due to the automation is precisely why they didn't notice the problem. Yet if every pilot always hand flew, we would probably have more total accidents.
I see this situation as similar to cars that can manage steering and speed on the road. You could let go of the steering wheel and pay no attention, but the car won't let you do that, as when you remove your hands from the steering wheel for more than a few seconds, the car alerts you. So what, really, is the function of auto-steering if you have to keep your hands on the wheel? Imagine if the aircraft required your hands on the yoke/stick, or the throttles, when you were on autopilot and autothrottles. You would notice things immediately (on aircraft with backdriven controls a la Boeing), but the convenience would be greatly reduced.
 
Spetsnaz55
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Wed Feb 17, 2021 9:42 pm

 
wjcandee
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Thu Feb 18, 2021 12:22 am

Spetsnaz55 wrote:


A lot of words to say, "You need to fly the plane." Or as Van VanderBurgh said, "If your aircraft is departing from its intended lateral or vertical path, the pilot flying will go 'Click, click. Click, click.' Autopilot and autothrottles OFF is always the first step. And I cannot overemphasize this point. As we look at the accident history out there, we see automation-dependent pilots with an airplane departing its intended lateral or vertical path [trying to control it with the automation] ... Don't let that happen. Get ahold of it. ... Find out what's going on here [by taking hold of the controls with automation off]. Not to mention, you should see how interesting it is to try to recover from one of these with the autopilot on. Or even worse the autothrottles: you should see what they can do to you."

https://www.youtube.com/watch?v=35Zy_rl8WuM at 10:55.

Prescient words from the 1990s.
 
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par13del
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Thu Feb 18, 2021 4:46 am

wjcandee wrote:
A lot of words to say, "You need to fly the plane." Or as Van VanderBurgh said, "If your aircraft is departing from its intended lateral or vertical path, the pilot flying will go 'Click, click. Click, click.' Autopilot and autothrottles OFF is always the first step. And I cannot overemphasize this point. As we look at the accident history out there, we see automation-dependent pilots with an airplane departing its intended lateral or vertical path [trying to control it with the automation] ... Don't let that happen. Get ahold of it. ... Find out what's going on here [by taking hold of the controls with automation off].

If you are in a FBW a/c what is there to feel via the controls, do they provide tactile feedback?
 
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saleya22r
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Thu Feb 18, 2021 9:39 am

I remember having read years ago that hand flying the -600 required more attention (I think it was a SAS pilot), notably in turbulence. True or tale? The -500 has the same fuselage length, both have bigger fins but even so, could these short 737 variants be trickier to recover when something unexpected happens, in this case a chain of events starting apparently with asymmetric thrust?
 
Chaostheory
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Thu Feb 18, 2021 1:01 pm

wjcandee wrote:
Spetsnaz55 wrote:


A lot of words to say, "You need to fly the plane." Or as Van VanderBurgh said, "If your aircraft is departing from its intended lateral or vertical path, the pilot flying will go 'Click, click. Click, click.' Autopilot and autothrottles OFF is always the first step. And I cannot overemphasize this point. As we look at the accident history out there, we see automation-dependent pilots with an airplane departing its intended lateral or vertical path [trying to control it with the automation] ... Don't let that happen. Get ahold of it. ... Find out what's going on here [by taking hold of the controls with automation off]. Not to mention, you should see how interesting it is to try to recover from one of these with the autopilot on. Or even worse the autothrottles: you should see what they can do to you."

https://www.youtube.com/watch?v=35Zy_rl8WuM at 10:55.

Prescient words from the 1990s.


Be wary of promoting VanderBurgh's Advance Manoevering Program (or whatever he called it). He was a massive proponent of using the rudder and that general advice instilled the poor flying techniques which proved ill-fated at Queens.
 
wjcandee
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Thu Feb 18, 2021 6:06 pm

Chaostheory wrote:
Be wary of promoting VanderBurgh's Advance Manoevering Program (or whatever he called it). He was a massive proponent of using the rudder and that general advice instilled the poor flying techniques which proved ill-fated at Queens.


Just wondering: are you a pilot who took his class, or did you read that somewhere?

The complete-misinterpretation of what VanderBurgh said by the poor pilot in the Queens event is what proved ill-fated at Queens. VanderBurgh repeatedly says in this course that the rudders on the AA fleet aircraft are very-powerful and you only need a slight touch of coordinated rudder in an upset recovery. He says you do NOT use opposing rudder in these techniques. And this guy was stomping on the rudder full-travel in both directions back and forth during light chop, not even an upset recovery. It was asinine, and it wasn't anything any reasonable person who took this course could have thought that VanderBurgh said.

It's like saying VanderBurgh was a massive proponent of using the yoke or sidestick, but now those are the Emergency Flight Controls only, because it turns out that if you misuse those, bad things can happen.

The real point of trying to discredit VanderBurgh is to move away from pilots with flying skills to cheap automation monitors who don't know how to fly, and to do so in the name of "safety". It was also for various parties to have an excuse for the idiotic conduct of that very-poor pilot, and an explanation by the manufacturer for why the rudder could detach from a transport category aircraft with inputs permitted by the travel of the control.
 
Exeiowa
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Thu Feb 18, 2021 6:31 pm

Automation reduces workload or activities, the problem with this is that when people are now not actively participating something else comes to fill up their time either by dictate or self boredom relief. Which then takes away from what they should be doing but is actually quite hard passively monitoring an automated system.

I have lane keeping assist on my car its main benefit to me has been driving long distance is less tiring as you do need to use any mental capacity for the task of staying between two lines so what you become is the system monitor because it sometimes makes odd decisions when exit ramps or lane splits appear etc
 
GalaxyFlyer
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Thu Feb 18, 2021 7:01 pm

The crew didn’t lack for experience or currency, but IF your only experience is flying an airliner under very controlled conditions, if it never has malfunctions, if the environment is always benign, being thrust into something entirely out of the normal means a lot of that experience is near worthless. Having students try to kill you or having serious engine failures is worth more than 8,000 hours of watching an autopilot. I probably had 1,000 hours of actual, hand flown on the steam gauges, IFR before I touched an autopilot control, some in a fast jet.
 
Sachmet
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Thu Feb 18, 2021 7:37 pm

As we are replaced in many sectors by machines our jobs are those of supervisors. Carbon being replaced by silicon. Two very different forms of pilots and when the artificial comes to its limits it just drops the controls: "Here pal your job now". Recipe for a catastrophe - not only in aviation.

Flying has long lost its charm. From the most desired dream of man's freedom to a boring routine job of a "glorified bus-driver". The obvious answer is to take the men of the loop - auto-everything. In fact we should replace the passengers too - they become a risk of contamination and more.

I feel for the "statistical irrelevant victims of automation" may they rest in peace. I fear we will see more of them in the future without any true change of direction. Some software patches here and there. Its really the software coders that fly the plane not the pilot - with the small difference that they will not be dead if they missed some condition that would fly the aircraft into a almost irrecoverable state like this one.

Lets hope the CVR will be found.

Question for the more experienced here: how many seconds had the crew to regain control after the Autopilot went off? In what position would the controls be in?
 
OldB747Driver
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Thu Feb 18, 2021 7:47 pm

GalaxyFlyer wrote:
The crew didn’t lack for experience or currency, but IF your only experience is flying an airliner under very controlled conditions, if it never has malfunctions, if the environment is always benign, being thrust into something entirely out of the normal means a lot of that experience is near worthless.

This is the best summary of the experience I've been trying to describe so far. This does not speak ill of the crew or their experience, but while folks generally see a 5000 hour F/O (which is not an insignificant amount of time), I saw that all but 150 hours of that person's time was on the 737 - a red flag in my [dare I say] experience.

At one point in my career I was an instructor at an ab initio flight training program and I was impressed with the ability of the 250 hour graduates in terms of flying through the various test scenarios. To be honest, I don't think I was that polished when I took my ATP at 1500+ hrs. As a Captain, having one of these graduates in the right seat I knew I could count on them to fly the airplane well but had no functional sense of the numerous ways you might set yourself up for heartache in the real world because they had no reference for it. Not their fault, but a shortcoming nevertheless.
 
FLYBY72
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Thu Feb 18, 2021 10:02 pm

zeke wrote:
FLYBY72 wrote:
Because you are only looking at the data the way you want to see it.

They were very vague on certain information and completely left some out.


I have posted additional data on this thread from the raw ADS-B data.

FLYBY72 wrote:
When the AP disengaged the plane did not "flick roll" as you put it.


That is what the ADS-B data shows, the initial upset started with a 8 degree heading change in 0.156 seconds, (which is a rate of 52 degrees per second). The change in headings and altitudes and rate of change can and were calculated by me between ADS-B data points.

FLYBY72 wrote:
They say the "aircraft rolled to 45 degrees" That would easily have been caused by having 1 throttle at climb power and the other at idle.


That is partially the cause, the main cause is the autopilot would have been making significant roll input to counter the yaw and to turn onto the requested heading of 075, and that roll input is neutralised when the autopilot disconnected. So the sudden removal of the aileron input is equivalent to a sudden roll input at 270 kts., the ADB-B data shows corresponding high turn rates.

FLYBY72 wrote:
They also do not say when the crew eventually brought the right throttle to idle. Why not? They have that data, but they didn't release it.


They have that data and it was in the draft of the preliminary report, and subsequently removed before publication.

FLYBY72 wrote:
The last aircraft coordinate recorded was 5°57'56.21" S 106°34'24.86"


That wasn’t the last point transmitted, the last ASD-B point transmitted is just 78 meters from the main underwater debris field.

FLYBY72 wrote:
What happened in those last 20 seconds?


I have posted the ADS-B data for the last 40 seconds on this thread, you can see for yourself, look at the headings and the elapsed time between points.

Image


ADS-B data, while relatively accurate does is not FDR data. ADS-B will say what the aircraft did, but not why.

I know what happened in the last 40 seconds. ADS-B does not say when, or IF, the pilots ever brought the right throttle back to idle. They sure talk a lot about recover training, but not if the FDR indicated they followed that training. They left that out!
 
OldB747Driver
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Thu Feb 18, 2021 10:52 pm

FLYBY72 wrote:
They sure talk a lot about recover training, but not if the FDR indicated they followed that training. They left that out!

I hate to say it but the likely reason accident investigators quickly release reports like this is because it serves one or more "not accidental" purposes, and I don't believe that purpose is to disclose all the pertinent facts, but more likely to either float the idea that the origin of the problem may rest with, say, the manufacturer ( thus reassuring those who invest and/or fly with the airline, keep the politicians who exercise oversight at bay) as well as disavowing the company's liability (the aircraft was maintained properly as well as we taught the crew correctly but they may not have done what we taught them...) in the short term while the investigation continues.
Last edited by OldB747Driver on Thu Feb 18, 2021 10:57 pm, edited 1 time in total.
 
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zeke
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Thu Feb 18, 2021 10:54 pm

FLYBY72 wrote:

ADS-B data, while relatively accurate does is not FDR data. ADS-B will say what the aircraft did, but not why.

I know what happened in the last 40 seconds. ADS-B does not say when, or IF, the pilots ever brought the right throttle back to idle. They sure talk a lot about recover training, but not if the FDR indicated they followed that training. They left that out!


Without giving too much away, it is possible to generate FDR like data from ADS-B data, the physics is well understood, the problem is non trivial as it involves non-linear equations of motion. It takes certain control inputs etc to generate the resulting trajectory. Likewise I can also work in the other direction and generate trajectory data from FDR data. FDR data like ADS-B does not say why either, just how.

The NTSC normally does release the FDR data with the preliminary report (eg the Lion Air Max crash), I don’t know which party objected to it being released with the preliminary report this time.

While they have included aspects of the recovery procedures, they haven’t included the mechanism how the loss of control precipitated. That information is known, what is unknown is why, and only the CVR will help there.
“Don't be a show-off. Never be too proud to turn back. There are old pilots and bold pilots, but no old, bold pilots.” E. Hamilton Lee, 1949
 
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SomebodyInTLS
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Fri Feb 19, 2021 2:42 pm

Sachmet wrote:
As we are replaced in many sectors by machines our jobs are those of supervisors. Carbon being replaced by silicon. Two very different forms of pilots and when the artificial comes to its limits it just drops the controls: "Here pal your job now". Recipe for a catastrophe - not only in aviation.


As I said before, this is actually a result of the legal cerification rules!

If society *wants* the pilots to ultimately be responsible then this is what the engineers have to do (the alternative is things like myths about A320s overriding the pilots and landing into forests...)
"As with most things related to aircraft design, it's all about the trade-offs and much more nuanced than A.net likes to make out."
 
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kwidenka
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Re: Breaking: 737 Crashed Indonesia

Fri Feb 19, 2021 3:47 pm

zeke wrote:
I just hope this is not a max. The last position is near where lion air went down.


Discussion title states 737-500
time to ride the sky
 
cat3appr50
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Fri Feb 19, 2021 4:14 pm

par13del wrote:
SomebodyInTLS wrote:
It's ironic that those arguing against automation never see that its very success is what they are discussing.
.

Unfortunately, the extremes still dominate the discussion, the positions usually taken is that one is either for 100% full automation or 100% no automation, hence the reason why we have accidents, the engineer mindset is to completely remove the pilot and the pilot mindset is to retain control.
The funny thing in all this is that the poor pilot is still held 100% accountable for signing the release sheet because he / she is the captain in charge.


IMO there's probably not many who believe in the one or the other 100% automation or 100% no automation. Current automation in commercial aircraft is generally great. Most pilots, even the older more experienced ones, appreciate the current level of automation. But it is unquestionable that automation (not just in aviation, but industry, etc.) can fail, even with leading edge technology. And when it fails (or not fails and is directing an aircraft into a situation that is not good, which IMO seems to fit this particular accident) assertive and proactive quick action must occur.

In aviation, that means that the pilots must resort to the manual flying skills that they learned in years of training leading up to their ATP license...best described by the saying..."click/click"...disconnect the A/P and A/T and hand fly the aircraft. The first priority of the aviation triad "aviate, navigate, communicate" is "Aviate." And one (by training, experience, etc.) needs to discern when the automation is leading one down a rabbit hole of which they may not be able to recover from, and act quickly..."click/click." All just my opinion.
 
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zeke
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Re: Breaking: 737 Crashed Indonesia

Fri Feb 19, 2021 4:36 pm

kwidenka wrote:
zeke wrote:
I just hope this is not a max. The last position is near where lion air went down.


Discussion title states 737-500


The title of the thread has changed a number of times, it did not say 737-500 when I made that post.
“Don't be a show-off. Never be too proud to turn back. There are old pilots and bold pilots, but no old, bold pilots.” E. Hamilton Lee, 1949
 
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par13del
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Fri Feb 19, 2021 4:58 pm

cat3appr50 wrote:
In aviation, that means that the pilots must resort to the manual flying skills that they learned in years of training leading up to their ATP license...best described by the saying..."click/click"...disconnect the A/P and A/T and hand fly the aircraft. The first priority of the aviation triad "aviate, navigate, communicate" is "Aviate." And one (by training, experience, etc.) needs to discern when the automation is leading one down a rabbit hole of which they may not be able to recover from, and act quickly..."click/click." All just my opinion.

I would expect that as more automation takes over even the training a/c will be automated, so in time the first item will be monitor the computer to see what it says as actual piloting skills will not be required and or taught to become a pilot.
Definitely future stuff..
 
bennett123
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Fri Feb 19, 2021 5:02 pm

5Two points occur to me;

1. Would it help if a fixed proportion of flights were flown by hand, particularly the take off and landing which is when most accidents happen.

2. People have referred to the situation when on autopilot that the system reaches a situation when it can't cope and hands the plane back to the pilot. Presumably, this is based on pre set combinations of factors. Is it possible for the system to give a warning to the pilots if it is x% away from the trigger point. The pilots would then be forewarned and could switch of the automation before it reached that stage. If the warning could indicate the issues at the same time, so much the better.
 
Chemist
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Fri Feb 19, 2021 8:45 pm

bennett123 wrote:
5Two points occur to me;

1. Would it help if a fixed proportion of flights were flown by hand, particularly the take off and landing which is when most accidents happen.

2. People have referred to the situation when on autopilot that the system reaches a situation when it can't cope and hands the plane back to the pilot. Presumably, this is based on pre set combinations of factors. Is it possible for the system to give a warning to the pilots if it is x% away from the trigger point. The pilots would then be forewarned and could switch of the automation before it reached that stage. If the warning could indicate the issues at the same time, so much the better.


This is somewhat consistent with something I suggested a ways back.
If all pilots flew all flights by hand 100%, you would undoubtedly see many more accidents.
Yet if no pilots were off autopilot above 1000 feet, you would see more pilot incompetency.
It seems that somewhere in between is the sweet spot where you have enough hand flying to maintain some competency yet not so much that lots of mistakes are happening.
I've read in these threads that some airlines mandate autopilot except at takeoff and short final. To me that's a recipe for pilot incompetency.
I'd suggest that some percentage of a pilot's flights ought to be hand flown up to cruise and down from cruise. I wouldn't be able to guess what that percentage would be. We ought to encourage some level of hand flying to maintain skills. This of course in addition to the simulator time where more serious situations can be exercised.
 
iamtom
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Fri Feb 19, 2021 11:31 pm

Let’s remember that when talking about automation being a contributing factor here, we make it clear it’s the 737-500’s outdated automation. If what we know turns out to be the cause of the crash, then it wouldn’t have happened in a more modern plane.

Perhaps an ageing fleet utilising outdated technology is an issue and type ratings for 737’s need to be looked at.
 
pugman211
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Sat Feb 20, 2021 1:02 am

bennett123 wrote:
5Two points occur to me;

1. Would it help if a fixed proportion of flights were flown by hand, particularly the take off and landing which is when most accidents happen.

2. People have referred to the situation when on autopilot that the system reaches a situation when it can't cope and hands the plane back to the pilot. Presumably, this is based on pre set combinations of factors. Is it possible for the system to give a warning to the pilots if it is x% away from the trigger point. The pilots would then be forewarned and could switch of the automation before it reached that stage. If the warning could indicate the issues at the same time, so much the better.


I think point 1 could work if it used an aural autocue system (like in a sat nav in a car) I.e. climb to FLxx, right turn at way point xx to heading xx etc,maintain speed xx etc etc

On point 2, there is 2 aspects. Would a modern system like a 787/A350 command what this 737 did? I doubt it as it uses 3 axis system. But if it did, then again, an autocue system notifying pilots of upcoming issues would help I.e. throttle split x%
 
MrBretz
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Sat Feb 20, 2021 1:55 am

Regarding Chemist's post about a "sweet spot" for flying with and without automation, it reminds me of a conversation I had a few years ago with a DL captain. I asked how long the AP is on. The response was the company would like it to be on as soon as the nose in the air. But they said they generally flew the airplane to about 18,000 ft to maintain their skills. Maybe that's the spot? I got the impression DL did not like that.
 
TTailedTiger
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Sat Feb 20, 2021 2:04 am

iamtom wrote:
Let’s remember that when talking about automation being a contributing factor here, we make it clear it’s the 737-500’s outdated automation. If what we know turns out to be the cause of the crash, then it wouldn’t have happened in a more modern plane.

Perhaps an ageing fleet utilising outdated technology is an issue and type ratings for 737’s need to be looked at.


That is no excuse. The crew is supposed to be monitoring the aircraft systems. It is incredibly unlikely this is the first time this issue has come up. Just the first time a crew ignored it and allowed it to run away from them.
 
sealevel
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Sat Feb 20, 2021 2:47 am

Find the d$%m cvr mem module, telemetry+audio to help put the puzzle together
 
hivue
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Sat Feb 20, 2021 4:46 am

MrBretz wrote:
Regarding Chemist's post about a "sweet spot" for flying with and without automation, it reminds me of a conversation I had a few years ago with a DL captain. I asked how long the AP is on. The response was the company would like it to be on as soon as the nose in the air. But they said they generally flew the airplane to about 18,000 ft to maintain their skills. Maybe that's the spot? I got the impression DL did not like that.


I posted a link upthread to a Blancolirio YT video where Juan and Scott Perdue/Flywire were reminiscing about AA wanting the AP on at 500 ft and off at 500 ft and how it was hard to keep up landing proficiency with that small an amount of stick time. My question is what's in it for the airline? They're still paying the crew's salaries even if the AP is doing the flying. I assume it's money somehow. Maybe the AP flies with sufficiently more efficiency than a human to save the airline a few dollars in operating costs? (But then again maybe it's safety related?)
"You're sitting. In a chair. In the SKY!!" ~ Louis C.K.
 
ryanov
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Sat Feb 20, 2021 7:21 am

It theoretically reduces pilot error accidents. I have to assume that’s what it is.
 
Sachmet
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Sat Feb 20, 2021 3:18 pm

hivue wrote:
I posted a link upthread to a Blancolirio YT video where Juan and Scott Perdue/Flywire were reminiscing about AA wanting the AP on at 500 ft and off at 500 ft and how it was hard to keep up landing proficiency with that small an amount of stick time. My question is what's in it for the airline? They're still paying the crew's salaries even if the AP is doing the flying. I assume it's money somehow. Maybe the AP flies with sufficiently more efficiency than a human to save the airline a few dollars in operating costs? (But then again maybe it's safety related?)

Safety? Ask yourself why there is no three man crew in the cockpit, no engineer any more? Silicon is cheaper than carbon. Those few dollar add up in the balance sheet. Pilots that are not busy flying can do other management stuff. Also if its easier to shift the blame away from the airline if its not human error responsible in an accident. You can add more stress to the carbon pilots and limit the time that things can get out of hand to +-500 feet. Machines are just so much easier to control. Drones everywhere. Teaching and training also have limits. You simply can't grow talent like fruits on a tree. With more and more planes in the air less talented crew you will get. Just keep them of the stick and pray that the autopilot will do the work...

Its a short step from telling the 737-500 autopilot design is outdated (30+ years) to that human pilots are much more outdated (100 000+years). Its easy to see where this is going and that yet another crew will take the blame without being able to defend themself.
 
OldB747Driver
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Re: Sriwijaya Air 737-500 (SJ182 CGK-PNK) crashes shortly after takeoff

Sat Feb 20, 2021 4:14 pm

Like most things in modern life, we've arrived at the point where "persistent problems" (like automation issues) are persistent because they are complex. Digging yet deeper, things are complex because while humans may be a single species, they are extremely varied in their psychology, or maybe I should say, in our attempt to 'make a living', we are easily convinced of positions that support those attempts.

Thus pilots think automation is to increase their capability to fly the airplane safely. Manufacturers think of automation in terms of justifying higher profits while insulating themselves from the liability of imperfect human pilots operating their product and airline managements think of automation as a way to keep their investors and passengers happy.

So pilots may think that an additional warning system will solve the problem, but then have yet another nuisance alarm/distraction while trying to coax the automation to do what they want it to do that ultimately gets ignored as much as monitored. Or add more automation for the rudder so we can remain blissfully unaware that the part of the automation that's failed is being compensated for by other automation... until it "hands it back" to the pilot unceremoniously as the autopilot algorithms hit their own logical dead end which it predictably will (oh the irony...)

From a manufacturer's position, we just got front row seats to how Boeing dealt with its automation in response to the -MAX; they created a compromise in design to minimize regulatory compliance (recertification) which resulted in automation that destroyed two loaded airplanes full of lives, pilots attempts to override the automation be damned. Hmmm... can't quite take the pilot out of the equation yet.

From the airline management's view, they've "managed" things to the point where retaining experience was not only NOT a priority but they figured they could do it cheaper without the experience... and they have relatively inexperienced crews doing weird things making them wish for even less pilot participation but without too many options for that to happen. In the mean time, they'll write ANOTHER volume of Procedures of what do when A, B, C, followed by C,A,B. Also B,A,C and occasionally C,B,C,A... i.e. the only decision we want pilots to make is which checklist to run, NOT what would I do if my entire family was on board? It all comes down to $$$ of course, but pilots, airline managers and manufacturers make their money from differing aspects...

Ultimately, there can can be no denying that while there are a lot of hands in the making, marketing and maintaining of an airliner, there are only a couple of folks at the pointy end when the crap hits the fan and that's why there is no replacement for experience - or development of that experience through direct transfer between crew members in actual operation. Once that transfer breaks down, the solutions get more expensive in both lives and $$$.

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