777 crash at san Francisco airport

[iamwiz82]

I have seen on several sources that the engines responded normally when commanded and had reached 50% power when the plane hit the ground. Those are big engines and take time to rev up. To sum it up, by the time they applied power, it was too late.

This is what the current report is:

Request to throttle up : minus 7 seconds
Stickshaker : minus 4 seconds
Crew calls Go Around, throttle advanced to full : minus 1.5 seconds

 

[LTC8K6]

I guess the -7sec throttle up may not have been to full power, but just some added power to try to correct their situation?

Has anyone said how they got off center?

 

[Dari]

They were not amateurs at all.. learn to read. The co-pilot who crash landed had like 14k hours a few thousand of those were on a 747...

Who cares how many hours he has if he wasn't in control? Who was (supposed to be) running the show? The newish pilot or the newish trainer?

 

[DrunkenSano]

Part of the article quoted from http://news.yahoo.com/sf-probe-brings-questions-over-auto-speed-controls-084646467.html

Bob Coffman, an American Airlines captain who has flown 777s, said the only way he could think of for the Asiana plane to slow as quickly as the NTSB has described would be if the autothrottle had somehow shifted into the idle mode.
"There is no way to get from a normal airspeed and normal position at 500 feet to an abnormally slow airspeed at 300 feet unless there wasn't enough thrust either deliberately or inadvertently," he said.
Only moments before the crash did the training captain realize the autothrottle wasn't controlling the plane's speed, Hersman said.
"This is one of the two hallmarks of complexity and challenge in the industry right now," said Doug Moss, an Airbus A320 a pilot for a major U.S. airline and an aviation safety consultant in Torrance, Calif. "It's automation confusion because from what Deborah Hersman said, it appears very likely the pilots were confused as to what autothrottle and pitch mode the airplane was in. It's very likely they believed the autothrottles were on when in fact they were only armed."

 

[coxmaster]

Who cares how many hours he has if he wasn't in control? Who was (supposed to be) running the show? The newish pilot or the newish trainer?

How in the hell are either of them "newish"??

The captain has >10,000 hours and the co-pilot has >13,000 hours.. That is FAR from being a new pilot..

 

[LTC8K6]

Who cares how many hours he has if he wasn't in control? Who was (supposed to be) running the show? The newish pilot or the newish trainer?

The teacher is always in command. He will be the one at fault for any student errors.

The only way the student would be blamed is if you could somehow show that the student deliberately made the errors and I don't think that's going to apply here.

 

[Tsavo]

I see your username means something 😉.

Here is a 777 behind a 737. Even though the 777 engines are hundreds of feet behind the 737 they definitely show their size.

I want one of those engines on a Cessna 152.

 

[John Connor]

The damn 777 engine is as round as the 737! 😱

 

[Tommy2000GT]

The 777 is actually bigger than the 787

 

[Eug]

The Globe and Mail, a Canadian paper is reporting that there could have been a mechanical failure of the autothrottle system. That is far from proven.
Anyway, the pilots have to monitor airspeed, autothrottle on or not, everybodys life depends on it.

http://www.theglobeandmail.com/news...-involved-mechanical-failure/article13105900/

The pilots of the Asiana jet that crashed here Saturday believed that they had set the auto-throttles, devices that can control the engines to maintain safe airspeed, but speed fell to unsafe levels anyway, the chairwoman of the National Transportation Safety Board said Tuesday.

Investigators in the cockpit of the wreckage found the auto-throttle switches set to the “armed” position, meaning that the auto-throttle could have been engaged, depending on various other settings, she said. The disclosure is far from conclusive, but raises the clear possibility that there was a mechanical failure or that the crew misunderstood the automated system it was using.

The chairwoman, Deborah A.P. Hersman, also said that interviews of the three pilots who were in the cockpit at the time of impact showed that the speed indicator on the flat-panel displays in the cockpit had drifted down into a crosshatched area, meaning that the instruments were saying that the plane was moving too slowly.

At the dual controls, the pilot flying the plane was undergoing initial training as he upgraded from a smaller plane, and was supervised by a veteran pilot who was new as an instructor, Hersman said. The instructor told investigators that between 500 feet and 200 feet in altitude, the crew was also correcting from a “lateral deviation,” meaning that the plane was too far to the right or left (she did not specify which) and realized they were too low.

At 200 feet, the instructor pilot told investigators in an interview, he noticed they were too slow. “He recognized that the auto throttles were not maintaining speed,” and began preparing the airplane to go around for another try. But it was too late.

 

[Dari]

The teacher is always in command. He will be the one at fault for any student errors.

The only way the student would be blamed is if you could somehow show that the student deliberately made the errors and I don't think that's going to apply here.

Thanks. So, it appears that the focus of this investigation is whether the auto-throttle was not just armed but engaged, right? If they assumed that it was engaged when it was only armed then this is more likely the trainer's error, right?

 

[Number1]

Thanks. So, it appears that the focus of this investigation is whether the auto-throttle was not just armed but engaged, right? If they assumed that it was engaged when it was only armed then this is more likely the trainer's error, right?

The focus of the investigation is how and why this crash happened. The autothrottle issue is but one of the parameters they will be looking at.

How is your colleague's wife doing?

 

[LTC8K6]

Thanks. So, it appears that the focus of this investigation is whether the auto-throttle was not just armed but engaged, right? If they assumed that it was engaged when it was only armed then this is more likely the trainer's error, right?

Going by what is in the media so far, yes. I think the focus will be around the A/T and the crew's understanding / monitoring of it.

You have a nice big display in front of each pilot that clearly shows several parameters related to the speed of the plane.

I think we also have another big factor with the plane being off center and the crew trying to get back on center.

Being off center is a serious error as well, and from what I have read, the crew may have been preoccupied with that problem.

Looking at the photos of the impact point, they did not correct the off center problem.

 

[BUTCH1]

The 777 currently has the single most powerful turbofan in the world. I am more familiar with the GE90 series, but the same holds true for turbofans on the 777 from Pratt&Whitney and RollsRoyce.

The GE90-115B used on the longer 777-300ER series for example, can provide up to 115,000 pounds of thrust! Actually, it can provide more thrust at 127,900 pounds, but I am not sure if the GE-90 is certified to fly commercially at that configuration.

One of the coolest experiences I had aviation wise was standing maybe 100 yards from a brand new and empty 777-300ER about to take off on a pre-delivery test flight. The sound of so much air being sucked in while going up to T/O thrust is indescribable. Until you have stood before and touched one of these you cannot appreciate the sheer size of one.

To compare, the original 747-100, had four engines that provide a "mere" 43000 pounds of thrust.

Yea, GE has done a heck of a job with the 90 series. My first flight was on a DC-9, I sat in back (the smoking section) right next to the engine nacelle, when it went to takeoff power it was cool to watch raindrops being sucked into the engine from the cowling and that was a tiny engine compared a 90 series. Here's a clip from BBC "Top Gear" in which they pull some car's across the 747's engines at full power, I could imagine how much worse it would be doing it with a 90 series, FF to 2:50
http://www.youtube.com/watch?v=ZJ9uWsvR1l0

 

[Dari]

The focus of the investigation is how and why this crash happened. The autothrottle issue is but one of the parameters they will be looking at.

How is your colleague's wife doing?

She's stable. They're originally from San Francisco but were moving to Shanghai so he could head up our office there. She only went back to finalize some things regarding furnitures after.

 

[Atomic Playboy]

I was traveling over the weekend (honeymoon, coming back into the states), and this was all over the news. You'd think the people in charge would have the sense not to have air disasters being shown on all the monitors in the airport, but no. Everywhere you look, nervous passengers seeing recreations of the crash from every angle right before they board their flights. On our flight back to Oregon from JFK, some girl in front of me turned her in-chair TV to CNN and promptly passed out, so I spent the next 6 hours seeing recreations of the crash as we flew through turbulence and thunderstorms. Not the best way to enjoy a plane ride, I have to be honest.

Glad more people weren't hurt, and a speedy recovery to those who were.

 

[AmdEmAll]

I was traveling over the weekend (honeymoon, coming back into the states), and this was all over the news. You'd think the people in charge would have the sense not to have air disasters being shown on all the monitors in the airport, but no. Everywhere you look, nervous passengers seeing recreations of the crash from every angle right before they board their flights. On our flight back to Oregon from JFK, some girl in front of me turned her in-chair TV to CNN and promptly passed out, so I spent the next 6 hours seeing recreations of the crash as we flew through turbulence and thunderstorms. Not the best way to enjoy a plane ride, I have to be honest.

Glad more people weren't hurt, and a speedy recovery to those who were.

I thought CNN Airport Network filters out things like air disasters from its broadcast?

And why don't you watch your own tv instead of someone else?

 

[vshah]

i keep my cellphone, passport, and wallet in my pocket at all times on the plane. that's all I really care about if we go down.

 

[davmat787]

Yea, GE has done a heck of a job with the 90 series. My first flight was on a DC-9, I sat in back (the smoking section) right next to the engine nacelle, when it went to takeoff power it was cool to watch raindrops being sucked into the engine from the cowling and that was a tiny engine compared a 90 series. Here's a clip from BBC "Top Gear" in which they pull some car's across the 747's engines at full power, I could imagine how much worse it would be doing it with a 90 series, FF to 2:50
http://www.youtube.com/watch?v=ZJ9uWsvR1l0

That actually happened in real life. In Brazil IIRC, a taxi was flipped over when it drove behind the runway while an aircraft was just starting its takeoff roll. They are supposed to stop if an aircraft is there, I believe that has been automated now.

 

[fuzzybabybunny]

http://www.theglobeandmail.com/news...-involved-mechanical-failure/article13105900/

The pilots of the Asiana jet that crashed here Saturday believed that they had set the auto-throttles, devices that can control the engines to maintain safe airspeed, but speed fell to unsafe levels anyway, the chairwoman of the National Transportation Safety Board said Tuesday.

Investigators in the cockpit of the wreckage found the auto-throttle switches set to the “armed” position, meaning that the auto-throttle could have been engaged, depending on various other settings, she said. The disclosure is far from conclusive, but raises the clear possibility that there was a mechanical failure or that the crew misunderstood the automated system it was using.

The chairwoman, Deborah A.P. Hersman, also said that interviews of the three pilots who were in the cockpit at the time of impact showed that the speed indicator on the flat-panel displays in the cockpit had drifted down into a crosshatched area, meaning that the instruments were saying that the plane was moving too slowly.

At the dual controls, the pilot flying the plane was undergoing initial training as he upgraded from a smaller plane, and was supervised by a veteran pilot who was new as an instructor, Hersman said. The instructor told investigators that between 500 feet and 200 feet in altitude, the crew was also correcting from a “lateral deviation,” meaning that the plane was too far to the right or left (she did not specify which) and realized they were too low.

At 200 feet, the instructor pilot told investigators in an interview, he noticed they were too slow. “He recognized that the auto throttles were not maintaining speed,” and began preparing the airplane to go around for another try. But it was too late.

Why does it take someone to "realize" that the airspeed was too slow? Wouldn't there be kind of a blaring alarm if the airspeed gets too slow at a certain altitude?

 

[Rudee]

i keep my cellphone, passport, and wallet in my pocket at all times on the plane. that's all I really care about if we go down.

the stuff in your pockets will just act as kindling to fuel the fire, which will consume your body, as in many airliner crashes.

 

[davmat787]

Why does it take someone to "realize" that the airspeed was too slow? Wouldn't there be kind of a blaring alarm if the airspeed gets too slow at a certain altitude?

You may have heard the term "stick shaker" being used during the NTSB press briefings. The stick shaker, as its name implies, violently shakes the yoke (or in Airbus' case, the 'stick) which warns the pilots of an impending stall, which in itself implies very low speed, or more accurately, and acute shortage of airlift which can be achieved other ways than a mere lack of airspeed.

And as the NTSB confirmed, the stick shaker was activated.

 

[DrunkenSano]

It was activated right before the crash though before anything could be done. Before the crash, the plane was not near stalling speed yet.

 

[BUTCH1]

the stuff in your pockets will just act as kindling to fuel the fire, which will consume your body, as in many airliner crashes.

If the fire has already gotten that bad what's in your pocket's would be irrelevant. The fuel tanks being in probably a 90% empty state worked in favor for this crash, if this were a departure accident it probably would have been an inferno as a 777 fuel load can range from 31,000gl to 47,000gl depending on the model. I guess we'll see upon further investigation if the belly tank survived the impact without rupturing, my guess is it did and the fire was caused by what was left in the wing tanks and the engine dislodging and rolling up against the mostly intact fuselage.

 

[evident]

Size matters, I'm just repeating what I've been reading from pilot's forums, in cruise flight the bigger 777 will handle turbulence with less difficulty than a smaller plane and I'm not saying bigger planes are harder to land, there not really, it just naturally takes more time to recover, the laws of physics apply, a 707 weighs 122,533lbs(empty) a 777 weighs 297,300lbs(empty). Sure it has much more powerful engines but it takes more time to move almost 3X the mass in a different direction. You can add an extra 500HP to a station wagon but it still won't "handle" like a Mazda 3.

really cool picture. 737 looks so small next to the 747 and 777