Asiana Boeing 777 Crashes at San Fran

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Postby deeknow » Mon Jul 08, 2013 11:15 am

(two topics merged)
Deans repaints: http://www.deeknow.com/
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Postby cowpatz » Mon Jul 08, 2013 12:51 pm

Looking and listening to reports it reinforces just how unreliable eye witness reports can be. One eye witness stated that the aircraft was too fast yet the officials are now saying that the aircraft was too slow to the point of the stickshaker being activated (this is not necessarily a stall just an approach to a pending one). Another stated that the aircraft was nose up at 20 degrees and another saying 3 degrees. To be as slow as suggested by officials would imply a nose up attitude closer to 12 to 15 degrees and this is consistent with what can be observed on the video. Some carriers require that the AP and auto throttles are disengaged upon reaching non precision approach minima if not before. This is the only logical reason that I can see for the airspeed to get so low. I just can't see how an incorrect VREF speed could be set in the FMC unless a Vref30 speed was selected but the final landing flap selected was 25 or even 20 [EDIT] Reports confirm Flap 30 selected and Vref of 137 kts. [End EDIT] This could have been missed by the crew (omitted the Before landing checklist) if they were preoccupied in trying to re-establish the aircraft back on Glidepath after initially being too high.
Thanks to advanced flight recording parameters the sequence of events will already be known. What will remain unclear at this stage is the human factors that were at play.
Last edited by cowpatz on Mon Jul 08, 2013 1:18 pm, edited 1 time in total.
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Postby Ian Warren » Mon Jul 08, 2013 1:25 pm

Not being gaudy , old days pre NZ scenery building i got so good coming into most the primary US airports , this runway was a regular , so with my 777 , d/loaded the Asiana scheme and had a look .. dang its been a long long time i've simmed outside New Zealand and it took a crash to do it , mentioned the runway is very long , how is it one dose not allow themselves that extra space further down a runway .. is this due to traffic movements , specific to the question since the runway is at tho small elevation ... enough to break a tail off .
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Postby jastheace » Mon Jul 08, 2013 2:25 pm

watching that video there was a whole lotta luck that that bird didn't roll, if that had happened there would have been a lot more deaths, amazing how tore up the interior is, given the fact that the fuselage stayed largely intact. but then the tail did absorb a massive hit.

Jason
In the ongoing battle between objects made of aluminum going hundreds of miles per hour and the ground going zero miles per hour, the ground has yet to lose.

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Postby cowpatz » Mon Jul 08, 2013 5:06 pm

Unofficial ADS-B data for those interested.

Speed is 4th from the right, altitude 2nd from right and vertical speed on the far right.





Vref was apparently 137 kts. Rate of Descent after passing 1400ft increased to 1380 fpm down until 600 ft.
Idle power to 400 ft. Late "SPEED" callout and then TOGA applied. Ideally the aircraft should have been onslope at 142 kts (137 + 5) at around 650 to 700 fpm ROD.
It would all appear consistent with an unstabilised approach. With a heavy aircraft, a high ROD and speed well below VRef the aircraft would be well on the backside of the drag curve with a significant delay in a transition from descent to climb.
Last edited by cowpatz on Mon Jul 08, 2013 5:08 pm, edited 1 time in total.
Remember the 50-50-90 rule. Anytime you have a 50-50 chance of getting something right, there's a 90% probability you'll get it wrong!

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Postby Ian Warren » Mon Jul 08, 2013 5:28 pm

Almost should have got the passengers out to push in the last few minutes , interesting to see the final reading obviously the flip/cartwheel
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Postby cowpatz » Mon Jul 08, 2013 7:01 pm

I would suggest there might be a little inaccuracy or lag in the readings.
Remember the 50-50-90 rule. Anytime you have a 50-50 chance of getting something right, there's a 90% probability you'll get it wrong!

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Postby Charl » Thu Jul 11, 2013 10:14 am

Quite coincidentally, this one popped up at the end of another Youtube clip I was watching.
Clear day, manual landing... this is what it looks like.

http://www.youtube.com/watch?feature=playe...KN-FWNq0#at=736

What in the name of all that's reasonable was going on in the Asiana flight's cockpit that day???
Luckily we can choose which airline we fly or do not fly on, I have a list which ends like this:
Garuda
Asiana
Last edited by Charl on Thu Jul 11, 2013 10:20 am, edited 1 time in total.
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Postby Ian Warren » Thu Jul 11, 2013 10:46 am

Clear as a Bell ... exactly how i did it in my CS777 cool.gif , ..... for those interested after watching that very clear and precise short film , flying in pointing out specific locations - one there was Moffet NAS airbase , a large base for the P3 , those two very large hangers very visually standing out were the Airship hangers for the USS Akron and Macon off the 1930s.

One thing that really got me also with this video was on the last final seconds ... the aircraft call-out go Retard - Retard , they then flick back to the aircraft and sound Retard Retard again , i understand - yes indeed it looks like a Retard laugh.gif

GARUDA ... that airline is one you should never fly on ...
Last edited by Ian Warren on Thu Jul 11, 2013 10:47 am, edited 1 time in total.
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Postby KiwiElf » Thu Jul 11, 2013 10:58 am

Charl wrote:
QUOTE (Charl @ Jul 11 2013,10:14 AM) <{POST_SNAPBACK}>
Quite coincidentally, this one popped up at the end of another Youtube clip I was watching.
Clear day, manual landing... this is what it looks like.

http://www.youtube.com/watch?feature=playe...KN-FWNq0#at=736

What in the name of all that's reasonable was going on in the Asiana flight's cockpit that day???
Luckily we can choose which airline we fly or do not fly on, I have a list which ends like this:
Garuda
Asiana


Too much reliance on autopilots and technology! (and not enough "real" flying).

Same with cars. Airbags and electronics may have made cars safer but statistics show they have made drivers more unsafe.

FLYING mag have recently written several articles and surveys on modern (new) pilots versus pilots of pre-glass cockpits, both for GA and all the way up to heavy transports... the verdict re steam gauge vs glass? Pilots trained on steam gauge technology generally flew better (with fewer accidents) than pilots trained in glass cockpits when the "power" goes off. The Cirrus pilots rated quite badly when having to hand fly without all the fancy technology available (and their accident statistics are far over what they should be compared to similar performance aircraft - no fault of the aircraft).

Personally, I'd blame the training (or lack thereof). Not enough good old fashioned "pilotage" skills.

The Asiana incident is case in point - hard to believe the PIC had 6,000 plus hours under his belt, (43 hrs on 777's) and even more difficult to believe, his instructor co-pilot didn't correct the mistakes earlier?
Last edited by KiwiElf on Thu Jul 11, 2013 4:16 pm, edited 1 time in total.
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Postby Charl » Wed Jul 17, 2013 1:15 pm

Came across this comparative clip, showing what happened, vs what should have happened.
http://www.youtube.com/watch?v=eXCwI6a1DqI...eature=youtu.be

Somebody uploaded an Asiana repaint on a B777 so I gave in and did the Rwy 28L approach at KSFO.
I managed the normal approach easily enough, and the tail-strike mush only after repeated tries.
(Eventually, by leaving the throttle levers right back, and then disarming the autothrottle on finals)

Looking at the animation, the 777 airframe must be pretty robust.
Mind you, I could've told you that after NZ124's landing at Auckland on Monday, gave us a right old test of maingear suspension limits...
Last edited by Charl on Wed Jul 17, 2013 1:25 pm, edited 1 time in total.
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Postby Splitpin » Wed Jul 17, 2013 1:43 pm

Great find , thanks Charl.
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Postby gojozoom » Wed Jul 17, 2013 3:35 pm

Well, this is interesting. Victims initiated a lawsuit against Boeing:

http://www.latimes.com/local/lanow/la-me-l...0,7439648.story

But why them?:

"Hersman (NTSB Chief) said analysis of the cockpit voice recorder indicated that until only shortly before impact, the pilots were unaware that the jet was flying far below the target speed and altitude for a safe landing. She added that there was no malfunction of the autopilot, auto-throttle or flight director systems. "

So why are they trying to blame Boeing based on a speculation that was proven to be wrong?

Dan
Last edited by gojozoom on Wed Jul 17, 2013 3:36 pm, edited 1 time in total.
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Postby cowpatz » Wed Jul 17, 2013 5:24 pm

This is one of the problems in the "piece meal" approach to releasing accident investigation "findings". Everything needs to be investigated and then looked at as a whole and released as such. Remember this is America and lawyers will be circling around the victims like sharks.
How do they know the Autothrottle was at fault when the NTSB said it had functioned normally? It is clutching at straws and the only reason that Boeing is being targeted is that they have the ability to pay....and pay big.
I am sure the human factors side of this accident would fill a telephone book, however, with respect to the aircraft I suggest that the survivors should actually thank Boeing for producing an aircraft that stayed together after such a huge impact and a complete 360 orbit. I am amazed that the fuselage and wings stayed intact. You can clearly see the aft pressure bulkhead in the photos.
Without delving into the human factors side of this saga it is possible to deduce what most likely happened and most Boeing pilots will be aware of one trap when using the FLCH (Flight level change) mode with the Autopilot disengaged.
The aircraft was initially high and fast and on a visual approach (Not VFR as there is a difference). In order to regain an appropriate glide path FLCH would most likely have been selected and at some stage the AP disconnected. Also some operators disconnect the autothrottles when on a visual approach but this has not been confirmed. So the aircraft would have been descending with the thrust levers closed and the PFD thrust annunciation would go from IDLE to HOLD. When in HOLD it is the pilots responsibility to control thrust when manually flying. There is no speed protection. Eventually they would have regained the correct slope and once established the speed reduced back towards normal. In attempting to stay on slope the pitch would be progressively raised with the thrust still in HOLD mode. If the AP were engaged the thrust would change from HOLD to SPD to maintain the MCP set speed. This is the Boeing trap with FLCH use and hand flying. I have seen it myself when positioning on a visual approach when on a close-in base turn. The focus is outside getting the turn and descent rate right and if not monitored correctly the speed can go below bug speed. I am not sure why Boeing chose to have it this way and I can only suggest that it probably has something to do with the thrust/pitch coupling that could cause a pilot induced oscillation (PIO) when the two get out of sync.
Now consider all the above and the fact the pilot flying had spent many hours flying AIRBUS aircraft that have thrust levers that do not move. In his mind he is used to not seeing the thrust levers move and that the AT's always control speed when in similar situations.
In a moment of increased stress he may have reverted to what he is most familiar with........
This is one reason why we only fly one heavy piece of tin at a time and don't mix types. How many times have you jumped into a European car from a Jap one and ended up turning the wipers on instead of the indicators or vice versa?
Just my 02c worth.
Remember the 50-50-90 rule. Anytime you have a 50-50 chance of getting something right, there's a 90% probability you'll get it wrong!

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Postby cowpatz » Wed Jul 17, 2013 5:36 pm

Remember the 50-50-90 rule. Anytime you have a 50-50 chance of getting something right, there's a 90% probability you'll get it wrong!

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Postby Charl » Wed Jul 17, 2013 6:38 pm

Whew. Amazing pics, thanks CP.
"The contents of the overhead bins may have shifted during flight..."
It's a jolly good thing that thing did not go inverted, I suspect.

cowpatz wrote:
QUOTE (cowpatz @ Jul 17 2013,5:24 PM) <{POST_SNAPBACK}>
...How many times have you jumped into a European car from a Jap one and ended up turning the wipers on instead of the indicators or vice versa?

Every time.

There is interesting research ongoing about man/machine interface, and human-in-the-loop.
The pilots that are saying
"Too much reliance on autopilots and technology! (and not enough "real" flying)."
are shooting themselves in the foot because the issues arise with the "real" part.
The trend will be to remove the human - as being too unreliable to monitor and interpret the machine full-time.

I'm for it actually, humans do other things better; and pilots will become people who manage the machines without getting into the operations loop.
Last edited by Charl on Wed Jul 17, 2013 6:41 pm, edited 1 time in total.
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Postby Splitpin » Wed Jul 17, 2013 8:19 pm

CP ....fascinating posts , thanks very much for taking the time.
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Postby Yob » Wed Jul 17, 2013 8:35 pm

Sad it happen, and they are targeting Boeing which is a bit annoying. Wait until the investigation is done then lawyer up and attack Boeing with evidence. Same goes for any company their attacking. although the airline should pay money to the two deceased females families. Sorry if that last sentence sounded wired could not think of another way to say it.
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Postby Ian Warren » Thu Jul 18, 2013 10:53 am

Interest shots especially the engine fan blades , the cost of each off those , you can see why a well over a quarter to cost of the entire aircraft .
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Postby Ian Warren » Tue Jul 23, 2013 1:27 pm

Well what do you no ... just found our pilot in training ... unsure.gif
http://www.youtube.com/watch?v=LkOT3fbc1O4
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