desertdog71
Girthy Member
THIS....
Is the lower left corner of the big picture you can't see.
Is the lower left corner of the big picture you can't see.
NTSB Press Release Asiana 214
- Thread starter A Life Aloft
- Start date
PhilosopherPilot
Well-Known Member
The industry standard for 121 jet operators is 1000' now. Most everyone has adjusted their stabilized approach criteria to that. If they haven't, they probably will in the not too distant future.
ASA/XJT went to 1000 feet a few years ago. Technically, they must be configured by 1000, but on speed by 500. At JetBlue we must be stable at 1000 in all conditions.
gotWXdagain
Polished Member
Whatever happened to the idea that Stabilized doesn't happen at one point on an approach, but is a fluid, continuous condition that begins with the beginning of final descent to the runway and ends with the landing rollout? If you put up a single gate, you can go through it on nearly any direction, but if you make it a long, thin tube with spikes on the walls (giggity), to make it all the way through demands precision during the entire transit, not just an "aim for the gate" mentality that many flight schools/departments are going toward.
seagull
Well-Known Member
You ignore the point that as an A-320 experienced pilot, the Captain student would have expected the power to come up and maintain the speed. This highlighted a clear flaw in the FCC architecture.
seagull
Well-Known Member
Well, regardless of what ASA/XJT does, my carrier, which is a 121 operator, uses 500 feet. We actually have MORE issues when it was 1000. We CHANGED to 500' for VMC a couple of years ago. Why would you think it is "industry standard"?
I really don't think it is the issue, or not the RIGHT issue. Flying the aircraft "by the numbers" with certain settings and things on the way in like following a script is all well and good, but the script might get a wrench thrown in it. I'd rather fly with someone that was comfortable holding 250 until near the marker and having it stable at 1000 feet than someone that always flew it by rote. That is not to advocate the former, but just using it as an example so you can understand the more extreme case. The person that can fly it fast knows the airplane and is likely to be more aware of the energy state than the person that flies by script, and so when the former ends up in an unusual corner point (like a slam-dunk busy environment after a Pacific crossing), they would be more likely to handle or, or recognize when its not where it should be.
Bumblebee
Commodore
you can be
expect and monitor? or just expect? Do we just expect that our machines are going to work without checking them? IDK, I'm not an airline pilot any longer, and was never a jet pilot, maybe the airline guys don't monitor their equipment to be sure it's doing what you've commanded or "thought" you commanded. I guess that would be a flaw in the system.
Bumblebee
Commodore
I wonder if we are talking past each other here...to me this goes with the pilot being able to fly the plane and being sure it is properly stabilized...not passing through a number that is within the criteria of being stabilized at a coincidental time.
RDoug
Well-Known Member
I'm sorry, but from a controller's point of view, saying this guy was stabilized at 1,000 because he happened at that precise moment to be at the proper speed and altitude (as he was passing through both parameters . . . rapidly) is a bit like me saying after a late turn to the ILS, "But he was within a 30° intercept at point X, just before he blew through the final. Not my fault."
Ain't buyin' it. This aircraft was never on a stable approach.
And telling Boeing they need to fix the airplane to preclude this type accident? We have a saying in ATC: "You can't make anything foolproof because fools are so ingenious."
Okay, back to the sidelines for me.
Ain't buyin' it. This aircraft was never on a stable approach.
And telling Boeing they need to fix the airplane to preclude this type accident? We have a saying in ATC: "You can't make anything foolproof because fools are so ingenious."
Okay, back to the sidelines for me.
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z987k
Well-Known Member
This.
Three words.
"Lowest common denominator."
There are more than a few who can pass a check ride, and nothing more.
PhilosopherPilot
Well-Known Member
That's industry-standard because at the Industry Safety Info-Share meetings the airlines (and even military) get together and pretty much agree that what the best-practices are. Stabilized approaches are high on the list of things that need to be addressed as an industry.
Look, the point is that stabilized approaches continue to be a leading cause of accidents/ incidents in the 121 world. It's not about "Ergh, Imma pilot and I can fix it." It's about how much risk you are assuming by "fixing" a bad situation. It isn't about the individual, but rather the aggregate risk, and if E'rebody flew that way, the risk would be far outside the acceptable range.
gotWXdagain
Polished Member
Which is exactly why a "gated" stabilized approach can be an inherently an unsafe practice, that allows the "I can fix it" mentality to continue down an approach but if the stars magically align right at the gate, you get to go through, even if the approach comes off the rails later on. A continuously stabilized criteria forces a pilot to constantly evaluate their approach as is, rather than shoot for a target or continue based on the false blanket that the target was met so the approach must be safe.
typhoonpilot
Well-Known Member
I would disagree with that statement. Their is a significant difference in the philosophy of how Boeing and Airbus design aircraft.
There is no way in a B777 transition course that the captain of this flight had not seen demonstrated, and most likely practiced, the B777 envelope protection features. That would include when they work and when they don't work.
He would have been taught to turn off both flight directors when on a visual approach. He would have been taught not to use FLCH on approach.
That all happened in the simulator. If he reverted to Aibusisms while in line training it then becomes the instructor's job to correct those mistakes.
I like the saying that RDoug used, "You can't make anything foolproof because fools are so ingenious".
Airbus pilots have found great ways to crash their aircraft with regularity even with all the built in protections.
Typhoonpilot
typhoonpilot
Well-Known Member
Would love to see the data on stabilized approaches coming out of your company. I mean the raw data from the QAR or whatever equivalent the aircraft have. I bet it might be enlightening.
TP
seagull
Well-Known Member
Wow, what this really is is a "I'm too good, this would NEVER happen to me" lovefest! I call B.S.
Typhoon, no, the transition could very likely would NOT have covered it. In fact, if you read the NTSB report, you'll see that there is good reason to believe it was NOT covered. In fact, most U.S. 777 pilots were not aware of that cornerpoint, including some test pilots. As you well know, Asia flying is pretty scripted in general, and a much slower pace than SFO during the busy arrival windows. It is a different ballgame. The cornerpoint they found is rarely encountered in the non-linear U.S. environment, let alone flying around Asia.
However, and more to the point, I am quite sure I could get MOST pilots into this corner-point if they did not know it was coming. It is much like the AF447 deal in that respect.
Too much pilot bashing here with little understanding in HF issues and how automation traps set in.
Typhoon, no, the transition could very likely would NOT have covered it. In fact, if you read the NTSB report, you'll see that there is good reason to believe it was NOT covered. In fact, most U.S. 777 pilots were not aware of that cornerpoint, including some test pilots. As you well know, Asia flying is pretty scripted in general, and a much slower pace than SFO during the busy arrival windows. It is a different ballgame. The cornerpoint they found is rarely encountered in the non-linear U.S. environment, let alone flying around Asia.
However, and more to the point, I am quite sure I could get MOST pilots into this corner-point if they did not know it was coming. It is much like the AF447 deal in that respect.
Too much pilot bashing here with little understanding in HF issues and how automation traps set in.
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seagull
Well-Known Member
My company reps attend those and sometimes host them. I think the 500' guidance comes from the FSF ALAR toolkit. What documentation do you have that "industry standard" is 1,000 feet in VMC?
seagull
Well-Known Member
I've seen it, in fact, I have ran performance analysis of hundreds of flights personally. The rates of exceedances are no higher than for other carriers based on data I have seen via infoshare and ASIAS. In fact, our rates are somewhat lower than a lot of them. Not that any exceedance should be tolerated.
seagull
Well-Known Member
Fact remains that Airbus or MD do not have the cornerpoint that caught this crew.
Cherokee_Cruiser
Bronteroc
Not necessarily. In the A320 had he brought back the thrust levers to idle, autothrust would have turned off and the thrust would have stayed at idle. It seems Boeing does something similar in that 'Hold' mode except autothrottles are still armed (and ready for another use/mode). In that sense, the action of manually bringing back the thrust levers to idle should have set off a mental alarm that he was now in manual control of his own thrust.
typhoonpilot
Well-Known Member
The problem with internet communication is you may not understand my tone. I am disagreeing without being disagreeable, I would hope.
This isn't about me or you. It is about what is right and what is wrong. We may have different opinions on that and debate may help education to both. The B777 training manual has had, for at least the last decade, envelope protection demonstrations as part of the Full Flight Sim training. It includes autothrottle wake-up and in that training there is usually a discussion of when it will not work. Where I worked it was brought up that it would not work in FLCH, TOGA, or below certain altitudes. Asiana training should have copied Boeing's syllabus so I can be pretty certain this was taught. Now we all know there are instructors differences and perhaps this pilot's instructor did not highlight this area, but it is in the syllabus.
The airplane has been flying with this system for 20 years and there has not previously been a major accident as a result. So it is hard to believe that the system is at fault. This crew failed on so many levels that they blew through any and all built in protections. I tried to highlight that in the previous posts.
The one thing that is standard procedure in the B777 that was not well understood prior to this accident was to turn off both flight directors when doing a visual approach. One of the main reasons for doing so is to ensure the autothrottles are operating in a speed mode. If only one is turned off nothing changes. The procedure is to turn both off and then the PM's back to on. Once both FDs are turned off the Autothrottle goes to SPD.
FLCH is not meant to be used on an approach. VNAV is fine if there is a profile to follow, G/S of course if there is an ILS glideslope, V/S or FPA in the absence of those, or nothing with the F/Ds turned off. They all work fine. The use of FLCH for the final descent on an approach is wrong. Why the instructor did not correct that mis-selection is beyond me. Why the captain thought it was okay is also beyond me. He would never have been taught that, nor would it have been allowed in his sim training.
I'm all for improvement in aircraft safety. That is why I strongly advocate 1000 feet as a cut-off point for stabilized approaches. I have highlighted the reasons in a previous post. The human factors you speak of are exactly why. Another one of those safety improvements is the Honeywell Smart Landing system. It is customer programmable to highlight unstable approaches with various call outs, to include "Unstable, Unstable", which the Asiana crew would most certainly have triggered by 450 AAL. That would have given them time to go-around.
My previous airline had the 500 foot in VMC cutout that you speak of for stabilization criteria. We saw a lot of raw data on unstable approaches taken well below 500 feet. In every case, when interviewed, the pilots are shocked that they took an unstable approach below 500 feet. They honestly did not know when they hit 500 feet because of the aforementioned loss of senses when so task saturated. In some cases the crew went around eventually, but initiated well below 500 feet. In some cases they pressed on to a landing, only just becoming stable at 200 or even 100 feet.
There really is just no reason to not be stable by 1000 feet in a heavy jet. You can maintain 170 to 5 for ATC easily and still meet the stabilization criteria by 1000 feet, or have a cut-out for speed only if on G/S and all other parameters within tolerance.
In terms of getting pilots into "corner points", I can do that too. In fact, it was my job for most of the last year at my previous airline. The objective being to show pilots, and more importantly instructors, when they became task saturated and how to effectively manage events; recognize when becoming task saturated; and how to prevent it from happening.
Asiana training and management share a lot of blame for placing that instructor in that seat without adequate preparation. He clearly was not up to the task. That is not pilot bashing, it is just a statement of fact. One that should be acted on by Asiana in hopes that they better train their instructors in the future.
Typhoonpilot
