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Boeing 777 down...

Looks like one of the two teenage girls who were killed may have been struck by an emergency response vehicle. That's just flat out horrible -- to survive such a mishap only to be struck and killed by an emergency response vehicle. There is an autopsy to be performed to determine her cause of death, but there has been statements from emergency response personnel that indicated this happened.

The NTSB is reporting today that the jet was being flown on final approach 40mph (35 KIAS) below the proper approach speed.

That's a lot folks! The approach speed is supposed to be 137 KIAS and the PIC flew the final approach at 102 KIAS. To put that into perspective, the final approach speed by my Cessna 310R is 106 KIAS! A final approach speed for a C-17 is between 110 KIAS and 125 KIAS depending upon weight.

I think the level of discussion in this thread has been very professional and cordial. I personally see nothing wrong with repeating what the NTSB has publicly reported. That's not speculation. That's establish fact. No one connected to this mishap, the airline, NTSB, emergency response, is saying anything other than this being pilot error. The NTSB speaks with authority and I trust what they say more than any other single source. I've not known them to release information without verification nor to release information prematurely and always without malice.

Ken
 
Saw some video on the news today of some of the passengers being treated by medics on the scene and what appears to be the port engine can be seen in the background. The video was highlighting the courage of one of the flight attendants who had a broken tail bone carrying people twice her size from the plane. With an injury of that kind one can only surmise that she was running on pure adrenalin.
 
Looks like the port side engine ended up in the dirt between 28L and 28R and burnt itself out. Probably got wrenched off when the jet did that spin-around move.
 
I do have of course a theory about why that happened (as soon as I've watched the ADS-B data replay) but I'd expect from any professional like Fliger747 that there will be no statement from these guys. It would be highly unprofessional to take part in such speculations in an official forum.
That one pax has been run over by an emergency vehicle is unfortunately not too uncommon and that's why crowd control training for the crew is so important.
Furthermore I'm 100% sure that the interpretation of 'the final approach was flown at 102kts' is incorrect....
 
If the aircraft really was allowed to get so slow one must ask how that could be allowed to happen. If the Storm's description of the flight protection system is even close to accurate one has to wonder why it didn't work as intended. Can it be over-ridden or disabled? If so, is that a common practice? Why did ANA's CEO come out with a statement so soon saying there was nothing wrong with the plane? Had the company already received statements from the crew indicating it was their fault? So many questions, so few answers.
 
pfflyers said:
If If the Storm's description of the flight protection system is even close to accurate one has to wonder why it didn't work as intended.
Click to expand...

It would have worked if it would have been needed....just check these brand new data:

The autopilot was disconnected at 1600 feet 82 seconds prior to impact, the aircraft descended through 1400 feet at 170 KIAS 73 seconds prior to impact, descended through 1000 feet at 149 KIAS 54 seconds, 500 feet at 134 KIAS 34 seconds, 200 feet at 118 KIAS 16 seconds prior to impact. At 125 feet and 112 KIAS the thrust levers were advanced and the engines began to spool up 8 seconds prior to impact, the aircraft reached a minimum speed of 103 KIAS 3 seconds prior to impact, the engines were accelerating through 50% engine power at that point, and accelerated to 106 knots
 
The data is interesting. The tail of the 777 began dragging the water at 7 seconds prior to impact with the rock wall below the runway threshold. The questions is, was the A/T in use or disconnected? They were about 33 kts fast at 1600ft(the approach angle/descent rate was stabilized but not the airspeed). I'm leaning more towards the A/T being disconnected and the throttles pulled to idle to stabilize the speed but not advanced to maintain 137 kts on final. When the Throttle of a 777 is pulled to idle, their is a brief but loud aural warning. Still the "barber poll" constraints on the PFD is 180/175(flaps 30) max spd and 113/117 impending stall/stall. The crew would have received GPWS and speed warnings when those parameters were exceeded(which did happen prior to water and land impact). Also, when the pilot pitched the nose up prior to the tail dragging the water, the speed barber poll on the PFD would have shifted up rapidly(moving the indicated impending stall/stall speed higher). So if all the indicators(the bleeding speed and the plane falling dangerously below the approach GP were displaying and giving warning normally, what was going on in the cockpit that would have distracted 3 sets of eyes and ears from catching all of this and initiating a go-around? Was all of it ignored or was there a glitch in the speed indications(brief or prolonged) that was sensor or software related? The latter had been reported a number of times by 777 crews and the FAA ordered an upgrade to a good bit of the main systems software.

I received an up to date digital copy of the 777 manual today(all variants included) and am soaking in more of the automation and safety systems. Whether PE or a combination of PE/Technical issues, a good bit of operating parameters were busted here. There is a saying about all this automation and relying on it too much. "Automation is always good enough, to kill you, fly the damn plane".


View attachment 89939
 
If you are high and fast or 'only' fast that close in, A/T is at idle as well already, so when you disconnect AP (and most probably) A/T as well (as the approach isn't really stabilized) the thrustlevers remain in idle.
It's quite difficult to judge when to add power in the high and fast case, especially in a heavy. If you apply power too soon that high mass is difficult to slow down again (within a reasonable distance).
Adding power too late on the other hand......
 
I agree but to pass along what a 777 Captain'Check Airman showed me in videos of their sim and actual approaches, in good meteorological conditions the 777 is very easy to maintain Speed and GPA/GS in making manual throttle/power adjustments and keeping the PFD rate of descent needle where it needs to be. The type has a lot of power and excellent throttle/power response so absent wind and turbulence, chasing the optimum rate of descent on the needle isn't an issue. But to go with Ken's assertion of the PE side of possibilities. it's possible the crew busted all normal parameters and warnings and reacted too late for whatever reason. As we well know, it wouldn't be the first time it has happened.
 
One possibility I heard that is as good as any right now is that each of the two pilots on duty at the time thought the other was watching airspeed. Neither wanted to say anything because in the Asian culture that would cause a loss of face. Eventually one of them spoke up but it was too late.

:isadizzy:
 
That's the keypoint: ' the 777 is very easy to maintain Speed and GPA/GS in making manual throttle/power adjustments and keeping the PFD rate of descent needle where it needs to be'
Once you are established it's easy but if you are at 1400ft still that much too fast, your target shifts entirely and you are much more heads up than in the cockpit to establish all the necessary visual cues and to check if your are able to 'salvage' the approach.
Most airlines have the rules that during a visual approach you have to be established at 500ft...at 500ft they were just 5kts below target wich is acceptable.

BTW in this famous video the test pilots where exactly on speed at their target altitude gate.....http://www.youtube.com/watch?v=SXVmsm_pmUo
 
Some data from the flight can be found here: http://nl.flightaware.com/live/flight/AAR214/history/20130706/0730Z/RKSI/KSFO/tracklog

Note how the speed drops from 141 knots to 109 kts in the last minute..

More info here: http://avherald.com/h?article=464ef64f&opt=0

Does this:

San Francisco CA [SFO]: June NOTAM #5: Navigation ILS runway 28L glide path out of service effective from June 01st, 2013 at 06:00 AM PST (1306011400) - August 22nd, 2013 at 03:59 PM PST (1308222359
Click to expand...

mean they had to do a manual landing? This was the pilots' first 777 landing there, but there was a training pilot with over 3,200 hours on the 777 in the cockpit. In total four pilots were in the cockpit during landing, and no one noticed the speed was too low?
 
Especiall during training you perform manual landings as much as possible regardless if the ILS is working or not as you want to learn to handle your new plane ASAP.
 
Bernt, do you think they deployed the speed brakes (@ the 1600/170 point) and forgot to retract them?

Good point Ferry_vO, 2 pilots in the seats and two in the jump seats(I had first heard there were 3 and then 4 pilots present from different sources). Again, if not a system failure that went unrecognized in time, what in the world was going on in that cockpit to make them miss the parameters so badly?
 
Speedbrakes is also a possibility. But IF they extend at full flaps they would auto-retract with thrust application.
Note that only 70sec prior to impact they still had the opposite problem, to get rid off the excess speed.
Just 35sec before impact they were suddenly facing the opposite problem and 25sec later thrust was applied.
 
luckydog said:
Good to see you back, Ken........that 310 doing OK ??
Click to expand...

It's doing great, thanks! The right engine overhaul is fully paid off several months ago and been getting the warchest back in normal order. Rehacked my AMEL night recency a few days ago in her.

Cheers,

Ken
 
The latest from the NTSB is that based upon further analysis and crew interviews, the PIC (the one doing his checkout in the 777) left the autothrottle in the armed position and it seems that it retained the previous setting which was for idle power to facilitate the faster descent to set up on the normal visual glidepath. Tragically, the flight crew failed to note this flawed setting and therefore failed to reset the autothrottle for normal approach speed!

It was not until the fateful timeline where at four seconds the first call for slow speed was made and 1.5 seconds for go-around that the first action was taken to take manual control of the throttles and initiate a full power go-around, which by that point was too late to prevent the impact on the sea wall.

I think we now know essentially all we need to know. This was pure pilot error. Terribly tragic, and disappointing. FWIW: the other pilot in the seat was a flight instructor doing the type conversion training for the PIC and he was a very new flight instructor.

Ken
 
bstolle,

The NTSB previously released what the target approach speed was supposed to be and then a day later released how many MPH the approach was flown below that target speed. What I wrote was simple math.

I posted the latest NTSB released information just above.

Nothing more I need to write on the issue.

Ken
 
The latest from the NTSB is that based upon further analysis and crew interviews, the PIC (the one doing his checkout in the 777) left the autothrottle in the armed position and it seems that it retained the previous setting which was for idle power to facilitate the faster descent to set up on the normal visual glidepath. Tragically, the flight crew failed to note this flawed setting and therefore failed to reset the autothrottle for normal approach speed!
Click to expand...

Here's the problem with that which there is a lot of missing information regarding actual status of the A/T and if the A/T button (IAS Speed Hold) was actually set on or not. From the manual: If the A/T Arm switches(L/R) were set on and the and the mode selector was set to the A/T button+ A/T button engaged, the FADEC will respond to what is set in the IAS display. As Bernt noted in the data, at and above 1600 ft they were @ 170 IAS which is 33 kts above where they needed to be but to facilitate the speed decrease, the Speed Control knob can simply be rolled to the Target Approach/Final Speed and the A/T-FADEC will reduce the power to Idle automatically and then respond with the appropriate amount of thrust when the Target Speed is reached. There's little to no lag when the TAS is reached as the sensors and FADEC react before the actual IAS falls below TAS. But as I mentioned to Bernt prior, I am wondering if they deployed the Speed Brakes to quickly bleed to speed down and left them deployed by mistake. Still the A/T would have responded before the speed approached and dropped below what was in the Speed Control window. I fall back to the actual status of the A/T versus what the crew thinks or says about it's status. I will concede that the crew erred and perhaps there's still possibly other mitigating technical factors but the missing pieces of information are far from being compiled in the proper manner to conclude the outcome.
 
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