Boeing Boeing 777 Crash Lands in San Francisco

[jim hardy]

interesting discussion of the approach here:

http://flyingprofessors.net/what-happened-to-asiana-airlines-flight-214-2/

He compares this landing to one by another 777 ten minutes earlier from an energy perspective..

On the other hand, AAR214 was never on a stabilized approach. Until about 30 sec before touchdown, it was high and fast. Only 3 miles out, it's 20 or 25 knots too fast, and 500 feet high. As a result, the pilot no doubt reduced power to intercept the glideslope from above. 1.5 nm out (nominally less than 40 sec from touchdown), he's finally on glideslope and at V ref , but with a high sink rate on low engine power. If he applied power at that point, the engines would take some time (a few seconds) to spool up, and he would further sink below glide slope, slow down, or both.

The situation can be appreciated more precisely (but more technically) by looking at the total energy of the aircraft, that is, the sum of the potential energy due to altitude plus the kinetic energy due to velocity. The total energy is given by


E=mgh+1 2 mv 2

where m is the mass of the aircraft, g is the acceleration due to gravity, h is the height of the aircraft, and v is the velocity. Because we don't know the weight of the aircraft, it's convenient to normalize the energy by mg , yielding the energy height

h E =h+v 2 2g

The plot below compares the energy height for the two aircraft:

Note that the energy of UAL852 decreases at a steady rate until about 6 nm out, where the rate of energy dissipation increases, because the aircraft is slowing. At about 3.5 nm out, the rate decreases, because the aircraft has hit its target approach speed and stops slowing down.

AAR214 has a much different trajectory. At about 3 nm out, the rate of energy dissipation increases a lot, because the aircraft is both too high and too fast. As a result, the power is reduced significantly, perhaps even to near idle, in order to simultaneously slow the aircraft and get it down to the glideslope. At about 1.5 nm out, it has about the right airspeed and altitude (and therefore energy), but the energy continues to decrease precipitously. If the pilot added enough power at this point, a safe landing might have been possible. But it takes several seconds for the engines to spool up, and the pilot may not have added enough power or done so early enough, so both the altitude and airspeed continue to decrease below their desired values. Indeed, at the last radar return, AAR214 would have been near its stall speed, and unable to pull up.

disclaimer - it's not an official report. But it looked apropos for a physics forum...

old jim

 

[AlephZero]

Where was the supervision? How is it that an inexperience pilot is given the responsibility of landing such an aircraft. He apparently had never landed a 777 at SFO.

Apparently he had plenty of hours experience on other aircraft types, though only 40-50 hours on the 777. Most of the other experience should be direct read-across, right back to his first solo flight.

Looking at the amateur video of the crash, it would be hard to think of a simpler situation for a first visual approach landing. Perfect weather, no wind, approach over water so no thermal turbulence, no obstructions like a mountain in an inconvenient place, etc...

The landing speeds etc for all commercial jet aircraft are very similar - basically because air traffic control have a much easier job if everybody is flying at the same speed and keeping the same distance apart. So even if he couldn't remember the exact design landing speed for a 777, he should have known the right ballpark figure.

The other pilot should have been checking the basics, of course, but asssuming this guy knew how to fly at all, what he did doesn't make much sense to me yet...

...the pilots took the plane completely off autopilot at 82 seconds before landing...

...and that makes no sense at all to me, unless the pilot in command (i.e. the "trainiee") decided to go around (a prefectly sensible decision IMO), but the "instructor" said "no, you can do it kid, just go for it..."

(Pure speculation, but there have been studies of the problems caused in cultures which naturally defer to authority rather than assertively challenge it when necessary)

 

[AlephZero]

It seems the "trainee pilot" was half way through his 777-specific training (i.e. about 50 hours of 100)

However the "instructor pilot" was flying in that role for the first time . That might explain a lot. The fact that you can do something doesn't mean you know how to teach, or supervise others!

http://www.bbc.co.uk/news/world-us-canada-23249012

 

[nsaspook]

http://www.aviationweek.com/Article.aspx?id=/article-xml/awx_07_09_2013_p0-595503.xml

The instructor pilot in command of Asiana Airlines Flight 214 arriving into San Francisco on July 6 said he had assumed the aircraft’s autothrottle system would keep the aircraft flying at 137 kt. as he and the “pilot-flying” in the left seat guided the 777-200ER to Runway 28L in visual conditions.

Too low and slow on the approach, the aircraft clipped the sea wall leading to the runway threshold with its main landing gear and tail as the pilots attempted to abort the landing. The left-seat pilot was in the process of getting qualified to fly the 777 for the Seoul, South Korea-based airline.
...
The 777 continued to slow as the pilots attempted to “correct a lateral deviation” as it descended from 500 ft. to 200 ft. “At 200 ft., the four PAPIs were red and the airspeed was in the hatched area,” says Hersman. The “hatched” markings on an airspeed tape warn pilots of an impending stall. The instructor pilot at that point recognized that the autothrottle was not maintaining speed and established a nose-high go-around attitude. He attempted to push the throttles forward for more power, but says the pilot-flying had already done so.

Information from the flight data recorder showed that the pilots first increased engine power from flight idle at 125 ft. altitude, reaching 50% thrust 3 sec. before impact.

Not knowing your true air speed while landing when the indicator is right in front of your eyes is inexcusable.

 

[OmCheeto]

http://www.aviationweek.com/Article.aspx?id=/article-xml/awx_07_09_2013_p0-595503.xml

Not knowing your true air speed while landing when the indicator is right in front of your eyes is inexcusable.

It depends on how many indicators are in front of your eyes.

A well trained operator would know which one to focus on. An operator with too little experience would be overwhelmed, IMHO.

I believe this may be why they replaced gauges in automobiles with idiot lights. The average person simply can't process that much information, in an emergency situation.

I use the above image, only as an example, as I manned all three of those stations, many, many years ago, and kept the reactor from melting down one day, during a very unexpected "event".

hmmm... Strange to think I could be that competent, being only 22 years old.
Yesterday, I refused to cross the street. (There were cars!)

 

[jim hardy]

esp minutes 22 thru 25

 

[nsaspook]

It depends on how many indicators are in front of your eyes.

A well trained operator would know which one to focus on. An operator with too little experience would be overwhelmed, IMHO.

I have very limited flight experience but that big indicator in center focus of each pilot in front of each wheel is hard to miss. All of the data so far from this crash points to a lack of energy to stabilize the flight path that should have been detected and corrected with plenty of time to spare.

777 flight console:
http://farm4.staticflickr.com/3202/3046863641_563cd759c8_o.jpg

 

[nsaspook]

(flight path information starts at about 10:00 in the video)
http://www.youtube.com/watch?v=I1GopE_siVY&feature=youtu.be
Now that we have the final NTSB onsite media update on the crash it's almost certain that pilot error will be the cause of this accident. It's a good thing Boeing makes one hell of a airplane with a wing that seems to have stopped a rollover and possible massive loss of life.

Boeing 777 wing test:

 

[Borek]

Another, slightly (un)related crash landing:

 

[Borg]

Another, slightly (un)related crash landing:

NTSB: Intern confirmed bogus crew names in San Francisco crash
Just too many interesting questions there. Who came up with the list? How did it get distributed to the media? Did the intern know it was a joke or was the intern just cluelessly confirming the names from the same press release? Can't wait for the congressional investigation for this one.

 

[nsaspook]

I'm going to hell for laughing at that.

 

[Borg]

I'm going to hell for laughing at that.

I'll save you a seat.

 

[Borg]

NTSB: Intern confirmed bogus crew names in San Francisco crash
Just too many interesting questions there. Who came up with the list? How did it get distributed to the media? Did the intern know it was a joke or was the intern just cluelessly confirming the names from the same press release? Can't wait for the congressional investigation for this one.

Yup. Just a matter of time...

http://news.yahoo.com/asiana-says-tv-station-damaged-reputation-083102599.html

An Asiana statement said it's mulling legal measures against both KTVU-TV and the NTSB because the report "badly damaged" the reputation of the airline and its pilots.

 

[TurtleMeister]

I've never flown a real aircraft, but I have a lot of experience with MS Flight Sim. So fyi, that is what I'm basing my analysis on. The jumbo jets are much more difficult to land manually (I understand the ILS was not operational for this runway?) than are the lighter aircraft. I have most of my experience with the 737, but I have flown the 777 occasionally. One thing I've noticed about the 777 is that it's more difficult to slow down (in flight) than the 737. Many times when attempting to land the 777 I will have to use the spoilers, which I do not normally have to do with 737.

From the flight tracking log linked to by Jim it looks to me like the flight 214 was initially coming in hot (too fast). He also had to make a 180 degree turn about five minutes out. Given the initial airspeed, I do not think I could make this landing in the 777. With some luck I might be able to do it with 737, but not the 777. I'm wondering if the pilot tried to reduce airspeed but over compensated? Easy to do in the 777 because the response time is sluggish.

I enjoyed the video "Children of Magenta" linked to by Jim. I've always wondered just how realistic MS flight sim really is. And there was one part in that video, at around 21, that helped to answer that question. The speaker asked "What's the most often asked question in the cockpits"? And the answer was "What's it doing now?". I had to laugh because I don't know how many times I've asked that same question (with a few other choice words) while flying with the autopilot.

 

[nsaspook]

http://english.yonhapnews.co.kr/national/2013/07/14/34/0302000000AEN20130714001800320F.HTML

SEOUL, July 14 (Yonhap) -- South Korea has sent a letter to the U.S. National Transportation Safety Board (NTSB) in protest to what it views as excessive disclosure of information linked to the ongoing investigation of the crash of Asiana Airlines Flight 214 in San Francisco, government sources said Sunday.
...
South Korea and the U.S. have been holding their own press conferences several hours apart, giving different impressions on their approach to the crash investigation. The U.S. investigators have made remarks hinting that the pilots might be responsible for the accident, while South Korea has countered the claims just hours later.

 

[wukunlin]

Why am I not surprised

 

[nsaspook]

http://www.aviationweek.com/Article.aspx?id=/article-xml/AW_07_15_2013_p22-596107.xml

While the NTSB's final analysis will likely take a year or more to complete, preliminary information from the cockpit voice and flight data recorders and pilot interviews indicate that distractions and automation surprises appeared to cause the pilots to lose altitude and airspeed awareness.

“I don't know how the whole crew could take their eyes off the speed,” a 777 fleet captain for a major carrier tells Aviation Week. “One of the basic tenets of a stabilized approach is speed.”

 

[nsaspook]

A bad story just got worse, The poor girl, I'm sorry but somebody should have checked her body for signs of life and moved her if she was dead before they foamed the plane and she was run over twice. The fact that she was still alive is heart breaking.

http://www.cnn.com/video/?/video/us...a-airlines-crash-fire-fighters-helmet-cam.cnn

 

[lisab]

A bad story just got worse, The poor girl, I'm sorry but somebody should have checked her body for signs of life and moved her if she was dead before they foamed the plane and she was run over twice. The fact that she was still alive is heart breaking.

http://www.cnn.com/video/?/video/us...a-airlines-crash-fire-fighters-helmet-cam.cnn

I can't bring myself to watch that video, which is widely available on US news sites. Erm, I mean "news" sites, because is it really news? Watching a tragic accident that took a 16-year-old's life does not make me a more informed citizen.

 

[nsaspook]

I can't bring myself to watch that video, which is widely available on US news sites. Erm, I mean "news" sites, because is it really news? Watching a tragic accident that took a 16-year-old's life does not make me a more informed citizen.

Yes, it is news because if it happens in the future at SFO we might not have the evidence of it happening. To call it an accident IMO is much too nice term for the lack of following basic ERT procedures.

http://bigstory.ap.org/article/after-airliner-crash-sf-chief-bans-helmet-cams

 

[dlgoff]

Erm, I mean "news" sites, because is it really news? Watching a tragic accident that took a 16-year-old's life does not make me a more informed citizen.

Using this kind of "news" now day's gives them a chance to debate who's at fault. Go figure.

 

[lisab]

Yes, it is news because if it happens in the future at SFO we might not have the evidence of it happening. To call it an accident IMO is much too nice term for the lack of following basic ERT procedures.

http://bigstory.ap.org/article/after-airliner-crash-sf-chief-bans-helmet-cams

I agree, I should not have called it an "accident". Not just the breaking of ERT procedures but the crash in the first place - calling any of this an accident implies it was inevitable, when in fact it was preventable.

But is the video news? I don't think so. I have no issue with making such videos and using them to improve emergency response procedures. What I disagree with is releasing them as some kind of sensational entertainment for the masses. If that girl was my daughter, I'd be devastated all over again.

Btw regarding that link you just posted - I hope all hell breaks loose over the decision to ban helmet cameras!

 

[nsaspook]

Using this kind of "news" now day's gives them a chance to debate who's at fault. Go figure.

We should debate who's at 'fault' in this accident response case. The NTSB is doing it with the crew of the plane. Criminal charges are not on the table, proper training and actions should be examined and there is very little incentive for the city to look very deeply into it.

 

[dlgoff]

I'm talking about TV news debates that goes on for ever with "experts" giving opinions not facts. This isn't news IMO. Of course we don't want something like this happening again.

 

[nsaspook]

http://news.msn.com/us/asiana-jet-partly-to-blame-in-california-crash

However, Asiana argued that the pilots and co-pilot believed the automatic throttle would keep the plane going fast enough to reach the runway — when in fact the auto throttle was effectively disengaged after the pilot idled it to correct an unexplained climb earlier in the landing.

How about a sign in the windshield of each pilot that says
"Plane does not fly by its self, always monitor airspeed"

 

[AlephZero]

How about a sign in the windshield of each pilot that says
"Plane does not fly by its self, always monitor airspeed"

I can't give you a reference, but counter-intuitively, monitoring airspeed on final approach is usually NOT done, because (as in this incident) you don't have time to take any meaningful action if the airspeed is wrong. So diverting your attention away from monitoring other things to check the airspeed is counter productive.

If everything else about the approach is correct, the laws of physics mean the airspeed will also be correct. The problem here seems to be that nobody on the flight deck decided the entire approach was sufficiently FUBAR that the best decision would have been to go round and try again.

 

[nsaspook]

Maybe for the big boys who depend on aids like auto-throttle to fly the plane but 'monitoring airspeed' is in most student landing training tasks. I agree that if you can see fish in the water, it's too late.

By midfield downwind, complete pre-landing checklist.
For Commercial, establish proper landing configuration.

- Gear down.

- Cowl flaps closed.

- Prop full forward (when manifold pressure below 15 in.)

Abeam touchdown point, add carb heat and reduce power.
Maintain altitude and level pitch attitude momentarily to dissipate airspeed.
Retrim aircraft to establish airspeed within flap operating range (white arc).
Lower flaps to 10 degrees.
Establish initial approach airspeed (1.4 Vso); retrim if necessary.

- Explain how airspeeds are arrived at (mfr.’s recommended airspeed, minimum airspeeds, and Vfe).

At 45-degree point from the landing threshold, clear for traffic and turn base.
Extend flaps and retrim if necessary to maintain approach airspeed; apply wind drift correction.
Lead turn to final to roll out on runway extended centerline.
Once the field is assured, extend final flaps.
Adjust pitch for desired airspeed and power for rate of descent.
Emphasize importance of monitoring airspeed.

http://webcache.googleusercontent.com/search?q=cache:fBXKA9sN424J:philip.greenspun.com/flying/tasks/normal-approach-and-landing.doc+&cd=4&hl=en&ct=clnk&gl=us&client=iceweasel-a

NTSB updates. (The Boeing Submission CVR/FDR timeline is great )
http://dms.ntsb.gov/pubdms/search/h...w=180&StartRow=166&order=1&sort=0&TXTSEARCHT=

76 Mar 31, 2014 Air Cruisers Submission
177 Mar 31, 2014 Asiana Airlines Accident Investigation Submissions
178 Mar 31, 2014 Asiana Airlines Submission Appendix A
179 Mar 31, 2014 Asiana Airlines Submission Appendix B
180 Mar 31, 2014 Asiana Airlines Submission Appendix C
181 Mar 31, 2014 Asiana Pilots Union Submission
182 Mar 31, 2014 Boeing Submission
183 Mar 31, 2014 Letter from KARAIB

 

[russ_watters]

I can't give you a reference, but counter-intuitively, monitoring airspeed on final approach is usually NOT done, because (as in this incident) you don't have time to take any meaningful action if the airspeed is wrong. So diverting your attention away from monitoring other things to check the airspeed is counter productive.

Oh well, just let it crash? That really makes no sense. And no, the approach is not so fast that you don't have time to correct if something is wrong. That's kinda the whole point of a missed-approach procedure.

If everything else about the approach is correct, the laws of physics mean the airspeed will also be correct. The problem here seems to be that nobody on the flight deck decided the entire approach was sufficiently FUBAR that the best decision would have been to go round and try again.

What is "everything else"? There are really only three main issues to deal with continuously:
1. Pitch controls airspeed.
2. Power controls descent rate.
3. Lineup.

Everything else is individual events (drop landing gear, drop flaps, change speed, etc.). The idea of a pilot not watching his airspeed while landing is just about as idiotic as a pilot reacting to a stall by holding the stick/yoke back full while his perfectly airworthy plane falls out of the sky like a brick...
http://en.wikipedia.org/wiki/Air_France_Flight_447

Or not knowing that you can overstress your airframe by applying full rudder (or any other control surface) deflection and ripping the tail off your plane:
http://en.wikipedia.org/wiki/American_Airlines_Flight_587

Airline safety has reached a tipping point. The airplanes are so safe and so automated (for safety's sake) that pilots are starting to develop glaring blind-spots in their skills.

 

[nsaspook]

http://www.sfgate.com/bayarea/article/Asiana-crash-No-reprimand-for-S-F-firefighter-5427996.php

'Bad message'

Reprimanding Johnson "sent a bad message throughout the department that getting to the bottom of something, getting to the truth, may not always be to your benefit," Smith said.

Randle said Johnson was being disciplined for doing the right thing.

"The goal appeared to have been to punish him for bringing the video to the attention of the department, which would never have disclosed what had occurred had it not been for the video," Randle said. "This amounted to punishing Mark for being honest in turning in the video."

 

[nsaspook]

http://www.ntsb.gov/news/events/2014/asiana214/abstract.html

PROBABLE CAUSE
The National Transportation Safety Board determines that the probable cause of this accident was the flight crew’s mismanagement of the airplane’s descent during the visual approach, the pilot flying’s unintended deactivation of automatic airspeed control, the flight crew’s inadequate monitoring of airspeed, and the flight crew’s delayed execution of a go-around after they became aware that the airplane was below acceptable glidepath and airspeed tolerances. Contributing to the accident were; (1) the complexities of the autothrottle and autopilot flight director systems that were inadequately described in Boeing’s documentation and Asiana’s pilot training, which increased the likelihood of mode error; (2) the flight crew’s nonstandard communication and coordination regarding the use of the autothrottle and autopilot flight director systems; (3) the pilot flying’s inadequate training on the planning and executing of visual approaches; (4) the pilot monitoring/instructor pilot’s inadequate supervision of the pilot flying; and (5) flight crew fatigue which likely degraded their performance.