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Boeing 777 down...

CWOJackson said:
In this case there was no power available. They were reporting no problems, they were well below the proper landing speed, the engines were at idle and the stick shaker activated 1.5 seconds before the crash.
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Yeah, something's seriously amiss here regarding the FADEC or Manual Throttle Response. Whether this is another instance of FOHE icing (with the older FOHE still yet to be replaced with the newer flat element design in this particular aircraft) or some other issue with the FADEC remains to be seen. The pilots were obviously trying desperately to deal with whatever was going wrong but there was zero response from the throttles/engines. As demonstrated in the above video, had engine power been available, then they would have flown out of this easily(before impact). There's a lot of discussion amongst 777 crews about known anomalies with the FADEC system on the type.
 
StormILM said:
Yeah, something's seriously amiss here regarding the FADEC or Manual Throttle Response. Whether this is another instance of FOHE icing (with the older FOHE still yet to be replaced with the newer flat element design in this particular aircraft) or some other issue with the FADEC remains to be seen. The pilots were obviously trying desperately to deal with whatever was going wrong but there was zero response from the throttles/engines. As demonstrated in the above video, had engine power been available, then they would have flown out of this easily(before impact). There's a lot of discussion amongst 777 crews about known anomalies with the FADEC system on the type.
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And yet the flight crew reported no problems whatsoever?

I'm fairly confident that the airlines, and in particular the NTSB with access to both the flight recorders and flight crew, have a firm grasp of what happened.
 
There is no documentation to point to engine issues. Further, the airline itself has already publicly ruled that out.

On the other hand, the first officer is supposed to call out airspeed deviations on final approach to the captain performing the landing (or vise-versa if the FO is performing the landing).

The NTSB has already released a number of factual conclusions. If they already know from the flight data recorders that airspeed on final was well below the proper configured approach speed, then I am confident they would have reported if the jet was producing lower than expected power for the throttle settings. There would be no reason for the NTSB to publish the issue with the airspeed without associating it with a low power indication. It would be easy to index the settings of the throttles with power output and see a deviation from expected results.

The NTSB reports that not until seven seconds prior to impact did a member of the flight crew direct an increase in speed. At four seconds prior to impact, the jet approached onset of stall as indicated by the stick shaker activation. Worse of all, it was not until 1.5 seconds prior to impact that a member of the flight crew directed the all important go-around call. It was likely that full power was not activated until that point, at which there would be insufficient time for the jet to recover from the descent and achieve a positive rate of climb.

What I have not yet seen reported by the NTSB is for how long the jet was well below approach speed. It is straightforward to set a normal power setting to achieve approach speed, but regardless of power setting, the vital component is speed. If the engines were not putting out expected power, then the flight crew should have noticed lower than expected airspeed, immediately directly increase of power, and note refusal of the engines to output power as demanded. With this done, one must conclude that full power go-around should have been initiated well before 1.5 seconds prior to impact.

Ultimately, regardless of the causes, the jet stalled about four seconds before impact and at that point, the jet was too low to the ground for the go-around to achieve a positive rate of climb before impact.

I am very afraid that this was crew error. Even if there were engine issues, I would still conclude that the crew was late to identify the situation and take the appropriate action, and as it was, failure to maintain proper final approach airspeed means the crew failed to maintain aircraft control. Therefore, all three of the critical flight actions were violated.

Ken
 
After seeing the video I can see why the witnesses thought it cartwheeled. I'm even more amazed now that the airframe stayed together as well as it did. Boeing engineers really designed a robust airplane.
 
Now they are saying that the pilot was in training in the 777, that this was his first flight in the type. However he is not new, and that he previously flew the 747... so heavies are not new to him. Now this raises a question... was he flying the approach as if he was still in the 747? Was he used to a slower approach?
 
Skyhawk_310R said:
There is no documentation to point to engine issues. Further, the airline itself has already publicly ruled that out.

On the other hand, the first officer is supposed to call out airspeed deviations on final approach to the captain performing the landing (or vise-versa if the FO is performing the landing).

The NTSB has already released a number of factual conclusions. If they already know from the flight data recorders that airspeed on final was well below the proper configured approach speed, then I am confident they would have reported if the jet was producing lower than expected power for the throttle settings. There would be no reason for the NTSB to publish the issue with the airspeed without associating it with a low power indication. It would be easy to index the settings of the throttles with power output and see a deviation from expected results.

The NTSB reports that not until seven seconds prior to impact did a member of the flight crew direct an increase in speed. At four seconds prior to impact, the jet approached onset of stall as indicated by the stick shaker activation. Worse of all, it was not until 1.5 seconds prior to impact that a member of the flight crew directed the all important go-around call. It was likely that full power was not activated until that point, at which there would be insufficient time for the jet to recover from the descent and achieve a positive rate of climb.

What I have not yet seen reported by the NTSB is for how long the jet was well below approach speed. It is straightforward to set a normal power setting to achieve approach speed, but regardless of power setting, the vital component is speed. If the engines were not putting out expected power, then the flight crew should have noticed lower than expected airspeed, immediately directly increase of power, and note refusal of the engines to output power as demanded. With this done, one must conclude that full power go-around should have been initiated well before 1.5 seconds prior to impact.

Ultimately, regardless of the causes, the jet stalled about four seconds before impact and at that point, the jet was too low to the ground for the go-around to achieve a positive rate of climb before impact.

I am very afraid that this was crew error. Even if there were engine issues, I would still conclude that the crew was late to identify the situation and take the appropriate action, and as it was, failure to maintain proper final approach airspeed means the crew failed to maintain aircraft control. Therefore, all three of the critical flight actions were violated.

Ken
Click to expand...

Ken, are you aware of the cause of BA 38's crash? This accident is nearly identical in many of the parameters of the BA 38 accident(which the former was proven 100% a technical problem as previously mentioned and not human error). Also, the 777's built in speed (and angle) protections(called FBW flight envelope protection by Boeing)
will react to such things as a slow speeds/impending stall and automatically advance the throttles/power to TOGA much the same as Airbus protection systems. Clearly in this case the protection systems-engines did not respond as they should have nor did they respond to manual throttle movement. Something system wise failed but this isn't the first time. Here's a partial list from the NTSB of other 777 incidents indicating engine and systems issues:

• Aug 2 2005: A Malaysian-registered 777 suffered a loss of thrust while climbing half an hour after take off from Perth before returning and landing safety.

Australian investigators identified computer failings which led to the pilots being given inaccurate speed readings and the US Federal Aviation Administration in Washington ordered a computer upgrade, warning that faulty data could cause difficulties with the flight controls, autopilot, pilot displays, brakes and autothrottles.

• July 1, 1998: An Air France plane en route to Paris from Sao Paolo suffered an "uncommanded engine shutdown". Investigators identified oil pump contamination as the cause.

• Jan 30, 2001: A United Arab Emirates 777 suffered an engine failure as a result of a defective fan blade. Investigators identified fatigue cracking as the cause.

• June 6, 2001: A Thai Airways 777 suffered a ruptured fuel tube en route from Taipei to Bangkok.

• June 23, 2005: A Japan airlines 777 stalled after taking off from Tokyo. An inspection revealed a hole in the turbine casing.

• Sept 18, 2006: The right engine of another Malaysian 777 shut down 40 miles north-west of Brisbane but was restarted.
 
From where I sit based on what the black box has revealed so far like it or not the engines were doing exactly what the PIC told them to do. He just did it way too late.
 
N2056 said:
From where I sit based on what the black box has revealed so far like it or not the engines were doing exactly what the PIC told them to do. He just did it way too late.
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That's odd because if that's the case then why didn't it climb instead of continue to sink? If you manually pitch the nose up with the FADEC A/T set(even at approach speed), the engines will spool up to at least maintain the speed that is set. If the pitch is too steep/airspeed too slow, the protections would have kicked in whether the A/T was engaged or not. The 777's FADEC is pretty quick in response when working properly. A/T wake up IS available in V/S, as the A/T is in SPD mode. If FLCH were selected with a go-around altitude(which setting is normal procedure) or otherwise set in the MCP,the airplane will commence a climb to that level once initiated.
 
So in that situation how long is that spool up time on that engine? I'll bet it's a lot more than the few seconds he had left when he finally tried to go around.
 
Storm,

You are pursuing a single theory. You have every right to do that. But, one thing cannot be argued. Flight crew procedures are objective. All along final approach course, the flight crew has a fundamental obligation to maintain proper approach speed and if they get slow, to immediately call it out and take immediate corrective actions. This is simply not happening when the first instance on the cockpit voice recorder for application of power and recognition of too slow approach speeds takes place only seven second before impact with terrain.

Beyond that, I have yet to hear from any direct investigative agency anything to point to engine issues. At this point, at best it can only be determined that the mishap is a combination of mechanical failure and crew error and the mechanical failure remains at this point 100% speculation. Yet, the passengers reported that coincidentally with impact, they heard the engines spool up. That complies with the NTSB report that a member of the flight crew directed go-around only 1.5 seconds prior to impact. Normal human reaction to a verbal go-around call would take about a full second at least before throttles were advanced to the full power setting. That's isn't speculation. It is based upon NTSB reporting and that is based upon a scientific review of the flight data recorder and cockpit voice recorder.

I have no reason to believe that in their initial review of the FDR and CVR that the NTSB would withold any information that indicated a lower than expected engine power output during any phase of the final approach segment of flight.

That's a pretty objective review of the information revealed so far. I see no reason to add much else to it.

Ken
 
I counted a full 15 seconds of nose up(pre-stall) unarrested excessive sink rate. Two guys I know who are 777 Captains said by that point speed and GPWS would have been raising hell in plenty of time to power to TOGA(manually) and have avoided this. The spool up speed of the PW4090 from idle to TOGA is around 6-7 seconds. The effect of the thrust would have been pretty immediate from my understanding. Considering the built in safety protections and other factors, there's just a lot wrong with this that appears to be "possibly" outside pilot error. A lot of folks in the 777 community are leery of a company jumping right out and declaring "non-aircraft/systems" were at fault when there are a good number of documented faults that have occurred with all variants in the fleet. The latest TO going out from GE regarding possible defects on a limited run on GE90's that are currently flying on 777's.
 
I'm good with waiting for the facts to be known. Maybe we should all agree to do the same?
Anyway, I'm out of this one.
 
N2056 said:
I'm good with waiting for the facts to be known.
Click to expand...

So am I. Watching the news today we have this woman from the NTSB sprouting "facts" like the throttles were at idle. It will take months to find the real cause. I know there are 'ambulance chasing' lawyers lining up to take action against the company so details seem to be being rushed out to satisfy these ghouls and line their pockets.

Let's wait until the full investigation is complete and get the fact then. May see a totally different result.
 
No argument fellas, agreed, just a good discussion of possible factors whatever the cause ends up being. Good point Aussieman, NTSB members have been known to throw erroneous info out more than a few times but when the press gets a hold of info it often takes a deeper turn off actual facts.
 
One "fact" that seems to being lost is that both the airline and the NTSB have access to the flight crew.

A telling "fact" is that the airline admitted pilot error so quickly. Because of liability issues, an airline is not going to admit that it is pilot error (completely their fault and their liability) unless it is absolutely clear that is the case.
 
One more telling "fact" is that although the PIC is a senior captain with many logged hours, he currently has only 33 hours on the T7, and this was his very first manual landing of a T7.
 
Where's Flieger747 during this convo?/ he flies 747s and could perhaps give us his opinion on the handling differences between the t7 and the 747..
How different is the T7 from the 747? how many hours had the PIC been flying on this trip before manually trying to land this plane?? Where's the port engine?? What was the nature of any communications asiana had with its flight crew immediately after the crash?? Could the time that the nose was high have been a time when the PIC had returned the throttle to idle knowing about the FOHE issue?
I havent had the opportunity of exploring all the facts as others here have due to lack of knowledge and connections. All i can do is speculate till the NTSB says something, and even then, in my opinion, its a toss of the coin. I'd really like to know though, and the above questions keep popping into my mind..
 
It gets to me how the press and "TV Lawyers" are weighing in on things with such incredulous/uninformed fashion. Ratings sell, that's a fact. And now, the damn "ambulance chasers" are piling on as usual. Makes me sick!

Here in this forum at least everyone who's discussed the matter has done so very objectively(even if we differ or not on some points) and brought in very valid points. Whatever went wrong will come out and probably not a single cause but possibly a cascade of things both human and technical/mechanical.

I am awaiting some detailed technical information from 777 crews(not slanted laymen term garbage from the press that detail some of the areas of concern that have long been a root for concern/distrust in certain systems on the type.
 
warchild said:
Where's the port engine??
Click to expand...

Warchild, as I posted earlier about a similar question Boeing design their wing mounted engines to break off in the event of a landing similar to the one at SFO in order to reduce the risk of fire from fuel spilling on to a hot engine.

Having said that one glaring omission from the NTSB head in media interviews is when they speak about what is heard on the CVR. All they are saying is that they hear one of the pilots ask for a go around. Nothing has been said about cockpit alarms being heard. As flight sim pilots know when we find ourselves in a similar position we are bombarded with all kinds of alarms and voice calls.

So until the full audio recording of the CVR is released we are all flying blind as to what has happened. At the moment I get the feeling that the NTSB is trying to pin the blame on 'pilot error' instead of indicating it there was some other problem.


 
I wondered about the missing engine too. Where did it end up? It could be under some other big part. There is a giant hole on the port side fuselage...

I'll bet the people on that United 747 taxiing up to that runway will not soon forget that morning either.
 
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