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http://www.cnn.com/2013/07/06/us/california-plane-incident/index.html?hpt=hp_t1
I hope everyone got out safely. Scary photos!
I hope everyone got out safely. Scary photos!
Evo said:One picture that says "the beginning of the debris" shows debris on the rocks at the water's edge, did the plane first hit the rocks? It looks that way. (picture #11 in lisab's link)
Stefanie Turner was walking to her hotel on the waterfront across from the runway at San Francisco International Airport when she saw a landing plane coming in at a bad angle, its tail very low.
"As we were watching, we saw the Asiana flight approaching, and we saw that the angle was wrong," she said. "The tail was too low as it was approaching.”
"The tail kind of clipped the runway. I think that’s when the tail broke off,” Turner said.
lisab said:Officials say two are confirmed dead, and "upwards of 60" passengers are still unaccounted for. Yikes, that's a lot!
http://www.cnn.com/2013/07/06/us/california-plane-incident/index.html?hpt=hp_t1
Weather at the time of the accident was good with light winds of 6 to 7 knots from the southwest and visibility of 10 nautical miles or more. Investigators will focus on several areas including the performance of the aircraft’s equipment, engines, systems and flight crew, as well as other factors concerning the dynamics of the approach. One item of particular focus for investigators is expected to be the status of runway approach guidance facilities. An FAA Notam (notice to airmen) for San Francisco indicates that, at the time of the accident, the instrument landing system glideslope for runway 28L was declared out of service from June 1 to Aug 22.
An FAA Notam (notice to airmen) for San Francisco indicates that, at the time of the accident, the instrument landing system glideslope for runway 28L was declared out of service from June 1 to Aug 22.
jtbell said:A video of the crash has surfaced. It was shot from about a mile away. You can see the plane doing a cartwheel-like reversal towards the end of its trip down the runway.
http://www.cnn.com/video/data/2.0/v...f-plane-crash-on-cam.courtesy-fred-hayes.html
jim hardy said:Anyone know how to interpret this site ?
http://flightaware.com/live/flight/AAR214/history/20130706/0730Z/RKSI/KSFO/tracklog
Looks like a quick descent with last minute attempt to pull up at only 85 knots, consistent with tail down attitude stall,
but I'm no expert.
thanks spook that's a link from your AW link...
Nwafflyer
I've been reading all these threads on short flights, and it makes me curious - what is the slowest possible flight speed (without stalling) for a dc-9, a 737, and airbus 319/320 and a 757 ?
RoseFlyer said:The landing speed is about 140 knots. [for a 777]
Too early to know for sure of course, but using a sort of anthropic principle, logic tells us that in order for there to be an accident these days without bad weather or a major mechanical failure, it requires a spectacular level of incompetence. Remember Air France a couple of years ago? Bad weather and a minor mechanical failure, but still the primary cause of the accident was a spectacular level of incompetence. Very sad.Office_Shredder said:Did they just not look at their airspeed meter or whatever it's called when stating they were going 137 knots? Because I feel like that goes beyond situational awareness to full blown incompetence
russ_watters said:...a spectacular level of incompetence. Very sad.
OmCheeto said:Happened to me at work one day. (Hospital, 25 years ago)
I worked in an office just 100 feet from the "Life Flight" landing pad on the top of the building.
Life Flight was coming in, so I peeked my head out the door, and watched the two ER guys waiting for the copter to land.
At one point, they both stopped looking out the tiny 10"x10" windows, and [STRIKE]ran[/STRIKE] bolted in my direction.
I slammed the doors shut, and heard a crash.
The copter pilot had come in too fast, and his tail rotor shredded on the edge of the rooftop.
The patient, and everyone else survived, thank god.
They brought in a crane the next day, and carried the copter away.
lisab said:Seems like medical helicopters crash quite a lot! Or, maybe they just make the news more...?
As a result of flying ill-equipped into risky conditions, medical helicopters crash at twice the rate of other air taxis
The first images from inside the stricken Asiana Airlines Flight 214 that crashed at San Francisco's airport on Saturday have been released - as it emerged the pilot was on his maiden training flight and had only 43 hours experience at the controls of a Boeing 777.
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.The South Korean jetliner ... was flying far too slowly to reach the runway and began to stall just before the pilot gunned his engines in a futile effort to abort the landing, the National Transportation Safety Board said. ... [NTSB Chairman Deborah A.P.] Hersman said the cockpit recorder revealed that seven seconds before impact there was a call to increase the plane’s speed. Three seconds later a “stick shaker” — a violent vibration of the control yoke intended to be a warning to the pilot — indicated the plane was about to stall. Just 1 1/2 seconds before impact, a crew member called out to abort the landing?
Hersman said her agency was a long way — perhaps months — from reaching a conclusion on what caused the crash. But with Asiana insisting there was no mechanical failure, the data from the flight recorders showing the plane far below appropriate speed and the fact that the pilots were controlling the plane in what is called a “visual approach,” the available evidence Sunday suggested the crew was at fault.
http://www.slate.com/blogs/the_slat...f_san_fran.html?wpisrc=newsletter_jcr:contentPerhaps adding to the pilot's difficulties was the fact that he had little experience landing at the San Fran airport. Hyo Min Lee told the Times that Lee Gang-guk had previously landed there but "not much" with the Boeing 777. She wouldn't specify exactly what that meant. Lee Hyomin, meanwhile, told the AP that Lee Gang-guk had never landed a 777 at SFO before.
http://www.washingtonpost.com/local...705-11e2-aa9f-c03a72e2d342_story.html?hpid=z1“We’re not talking about a few knots here or there. It was significantly below the 137 knots” required for the approach, NTSB Chairman Deborah A.P. Hersman said in describing data taken from the cockpit and flight data recorders. “We do hope to interview the crew members within the next few days.”
. . .
russ_watters said:I'm having Air France flashbacks.
“Ultimately, it’s the trainer pilot who is responsible for the flight,” Mr. Yoon, the Asiana president, said, referring to Lee Jeong-min, 49, the more experienced pilot who sat in the co-pilot’s seat when Lee Kang-guk was landing the plane. He had 3,220 hours of flying time with 777s.
“Familiarization flights” are part of the routine for pilots learning to fly a new kind of plane, officials at both the Transportation Ministry and Asiana said. At Asiana, the pilots are required to go through manual and simulator training — Asiana has run its own simulator training center since 1998 — and make 20 familiarization flights in the presence of more experienced “mentor” or “trainer” pilots.
It seems to me like we may have reached a critical mass or tipping point where automation is causing pilots to become less skilled. 10,000 of flight time doesn't mean a whole lot if 9,500 of it was spent watching the autopilot fly the plane! In addition to the stupid mistakes, you also have to wonder how pilots with little stick-and-rudder time would do in true emergencies, such as in The Miracle on the Hudson (captain Sully was a military pilot and therefore had a ton of stick-and-rudder time).Jim said:This could be one instance where the computer would have done a better job.
russ_watters said:For those who don't remember/didn't see it, here is the Air France thread:
https://www.physicsforums.com/showthread.php?t=317490&page=9
The basic cause of the Air France crash was the pilot at the time just plain did the opposite of what he needed to do to fly the plane - nearly constantly, for four minutes, while the plane dropped out of the sky from 35,000 feet. ...
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It seems to me like we may have reached a critical mass or tipping point where automation is causing pilots to become less skilled. 10,000 of flight time doesn't mean a whole lot if 9,500 of it was spent watching the autopilot fly the plane! In addition to the stupid mistakes, you also have to wonder how pilots with little stick-and-rudder time would do in true emergencies, such as in The Miracle on the Hudson (captain Sully was a military pilot and therefore had a ton of stick-and-rudder time).
However, Troadec also made it very clear that BEA was not blaming the pilots alone for the accident:
“If the BEA thought that this accident was only down to the crew, we would not have made recommendations about the systems, the training, etc.”
He went on to say:
“What appears in the crew behavior is that most probably, a different crew should have done the same action. So, we cannot blame this crew. What we can say is that most probably this crew and most crews were not prepared to face such an event.”
In fact, BEA made a total of 25 recommendations (pdf) covering everything from better training of aircrews to changes in display logic to improvements in search and rescue. Training pilots to fly aircraft manually at high altitudes is seen as a major need.
Many of the recommendations also deal with the so-called “automation paradox,” i.e., which as I wrote about for IEEE Spectrum concerns the situation where “the more reliable the automation, the less the human operator may be able to contribute to that success. Consequently, operators are increasingly left out of the loop, at least until something unexpected happens. Then the operators need to get involved quickly and flawlessly.”
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.
Astronuc said: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.
Borg said:...the pilots took the plane completely off autopilot at 82 seconds before landing...
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.
nsaspook said: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.