Asiana B772 at San Francisco on Jul 6th 2013, touched down short of the runway, broke up and burst into flames
An Asiana Boeing 777-200, registration HL7742 performing flight OZ-214 from Seoul (South Korea) to San Francisco,CA (USA) with 291 passengers and 16 crew, touched down short of runway 28L impacting the edge separating the runway from the San Francisco Bay 115 meters/375 feet ahead of the runway threshold while landing on San Francisco's runway 28L at 11:27L (18:27Z), the tail plane, gear and engines separated, the aircraft came to a rest left of the runway about 490 meters/1600 feet past the runway threshold. Following first impact at high angle of pitch the aircraft lost gear and tail section, skidded along the runway, the tail and right wing rose to about 45 degrees, the left wing entangled with ground sending the aircraft in a spin and separating the engines, the aircraft turned around counterclockwise by nearly 360 degrees with the tail coming down again and stopped, burst into flames and burned out, 305 occupants were able to evacuate the aircraft in time and are alive. 3 people are confirmed killed in the accident, 10 people are in critical condition, 38 more are in hospital care with injuries of lesser degrees, 82 occupants received minor injuries. The majority of survivors escaped without injuries.
Emergency services initially reported all occupants have been accounted for and are alive. Emergency services repeated ALL occupants have been accounted for in response to media reports that two people have been killed. A number of people were taken to hospitals with injuries of varying degrees. In a later press conference the fire chief of San Francisco said, not all people have been accounted for, two people were confirmed killed in the accident. In a second press conference Saturday evening (Jul 6th San Francisco local time) the fire chief reported, all passengers and crew have been accounted for, final numbers were 2 occupants killed, 10 in critical condition, 38 with serious injuries, 82 with minor injuries, 175 uninjured. The confusion about people being not accounted for was the result of survivors being taken to two different locations at the airport. The two fatalities were 16 year old Chinese girls travelling as part of a school outing.
Asiana confirmed their aircraft suffered an accident while landing in San Francisco, there were 291 passengers and 16 crew on board.
The General Hospital in San Francisco reported they received 10 passengers from the flight OZ-214, 8 adults and 2 children, all in critical condition. In the evening of Jul 7th PDT the hospital reported 6 passengers were still in critical condition. On Jul 12th the hospital reported a third girl has succumbed to injuries received in the accident, 2 passengers remain in critical condition.
The city of San Francisco and emergency services in a joint press conference reported that emergency services responded post landing, 48 people were transported to hospitals, 190 passengers were collected and taken to the terminal, 82 of which are probably going to be tranferred to hospitals, there are some people unaccounted for. The aircraft carried 291 passengers and 16 crew, total 307 people on board. There were two fatalities. In a second press conference Saturday evening the fire chief corrected the earlier statement now stating that all passengers and crew have been accounted for, the earlier confusion in Saturday afternoon's press conference was caused by two locations at the airport used to take survivors to. There were 305 survivors, 2 fatalities, of the 305 survivors there are 10 in critical condition, 38 received serious injuries, 82 minor injuries.
The airport was completely closed for about 5 hours, then runways 01L/19R and 01R/19L reopened, both runways 10/28 remain closed.
The NTSB reported the Boeing 777 of Asiana, flight 214, approached runway 28L when it suffered an accident, three investigators from the West Coast as well as a response team from Washington have been dispatched on scene. Korea's ARAIB have been invited to join the investigation.
ATC recordings show, the aircraft was on a normal approach and was cleared to land on runway 28L, no emergency services were lined up, all traffic was running normally. During a transmission of tower shouting in the back of the tower is heard, emergency services began to respond, all aircraft on approach were instructed to go around. The airport was closed. United flight 885, waiting for departure at the hold short line threshold 28L, reported people were walking around both runways, there were a number of people near the numbers of runway 28R, obviously survivors.
An observer on the ground reported that the approach of the aircraft looked normal at first, about 5 seconds prior to impact the aircraft began to look low and then impacted the sea wall ahead of the runway.
On Jul 7th the NTSB reported in a press conference at San Francisco Airport, the crew was cleared for a visual approach to runway 28L, the crew acknowledged, flaps were set at 30 degrees, gear was down, Vapp was 137 knots, a normal approach commenced, no anomalies or concerns were raised within the cockpit, 7 seconds prior to impact a crew member called for speed, 4 seconds prior to impact the stick shaker activated, a call to go-around happened 1.5 seconds prior to impact, this data based on a first read out of the cockpit voice recorder. According to flight data recorder the throttles were at idle, the speed significantly decayed below target of 137 knots - the exact value not yet determined -, the thrust levers were advanced and the engines appeared to respond normally. The NTSB confirmed the PAPIs runway 28L were available to the approaching aircraft before the accident, however were damaged in the accident and thus went out of service again. The localizer was available, the glideslope was out of service, according NOTAMs were in effect. There were no reports of windshear and no adverse weather conditions. The air traffic controller was operating normal, no anomaly was effective, until the controller noticed the aircraft had hit the sea wall. The controller declared emergency for the aircraft and initiated emergency response. ARAIB and Asiana personnel have arrived on scene and have joined the investigation. The Mayor of San Francisco reported runway 10L/28R was cleared for service.
On Jul 8th 2013 the NTSB reported the pilots' flight bags and charts were located, the proper (approach) charts for San Francisco Airport were in place at the cockpit. There were 4 pilots on board of the aircraft, they are being interviewed on Jul 8th, which will be determine who was pilot flying and who was in command at the time of the approach. The cockpit was documented and the switch positions identified. Both engines were delivering power at time of impact consistent with the flight data recordings, the right hand engine found adjacent to the fuselage showed evidence of high rotation at impact, the left hand engine liberated from the aircraft also showed high rotation at impact. The aircraft joined a 17nm final, the crew reported the runway in sight before being handed off to tower. 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 vertical profile needs to be assessed first. There was debris from the sea wall thrown several hundred feet towards the runway, part of the tailcone is in the sea wall, a significant portion of the tail is ahead of the sea wall in the water.
On Jul 9th 2013 the NTSB reported in their third press conference based on pilot interviews, that they were requested to maintain 180 KIAS until 5nm out, then extended the flaps to landing configuration of 30 degrees (160 KIAS max speed), they were high descending through 4000 feet, set vertical speed mode at -1500fpm, at 500 feet AGL the PAPIs were showing three red one white and the pilot began to pull back on the yoke to reduce rate of descent assuming the autothrottles would maintain the speed set to 137 knots. A lateral deviation developed taking the attention of the crew. Descending through 200 feet all PAPIs were red and the speed had decayed into the red/black marked range, the training captain realised the autothrottles were not maintaining the target speed, at that point the pilot flying had already started to move the levers forward. There were three pilots in the cockpit, the captain under supervision was pilot flying occupying the left hand seat, the training captain was pilot monitoring occupying the right hand seat, the relief first officer was occupying the observer seat, the relief captain was in the cabin at the time of the landing. The captain under supervision, 9700 hours total flying experience with 5000 hours in command, type ratings for B737, B747 and A320 having been ground instructor and sim instructor as well captain on A320s from 2005 to 2013, had flown 10 legs for a total of 35 hours on the Boeing 777-200 so far and was about half way through his supervision. The training captain, about 3000 hours on B777 and about 10k hours in command, was on his first flight as training captain, he was pilot in command, the two pilots had never flown together before. The relief first officer had 4600 hours of total experience, about 900 hours on B772 and about 5-6 landings into SFO as pilot monitoring on B772. The autothrottle switches were found in the armed position post accident, it is not yet clear in what mode the autothrottles were and whether autothrottles were engaged or not. Two flight attendants in the aft cabin were ejected from the aircraft during the accident sequence and were later found up and aside of the runway with injuries. At least one of the escape slides inflated inside the cabin. There was a post accident fire at the inboard section of the #2 engine, an oil tank had ruptured leaking oil onto the hot engine. The thrust reversers were found stowed, the speedbrakes were retracted. Both engine fire handles were pulled and agents discharged, the APU fire handle was pulled and agent discharged as well. Traces at the sea wall reveal that the main landing gear struck the sea wall first, then the tail of the aircraft.
On Jul 10th 2013 the NTSB reported in their fourth press conference, that the captain under supervision and training captain had flown the takeoff from Seoul, had taken about 5 hours of rest enroute and took their seats again about 90 minutes prior to landing. During the last 2.5 minutes of flight there were multiple autopilot and multiple autothrust modes. The various modes needs to be assessed to see whether they were result of single pilot actions or result of interconnected system responses. The aircraft received landing clearance about 1.5nm before touchdown. Six of twelve flight attendants are still in hospital care and were not interviewed so far. The flight attendants at doors 1R and 2R were pinned by evacuation slides deploying into the cabin. 3 of four flight attendants at the rear doors were ejected from the aircraft together with their seats. None of the passenger seats were ejected from the aircraft. The six uninjured flight attendants were interviewed and reported that after the aircraft came to a stop, one of the flight attendants at 1L went to the cockpit and checked with flight crew whether an evacuation should be initiated, the flight crew instructed to not initiate the evacuation. The flight attendants at 2L saw fire outside the aircraft near seat row 10, consistent with the position of the right hand engine's position adjacent to the fuselage, and initiated the evacuation. 90 seconds after the aircraft came to a stop door 2L closely followed by 1L opened and the evacuation began. 120 seconds after the aircraft came to a stop the first emergency responders arrived on scene, about 150 seconds after the aircraft came to a stop the first fire agent was applied to the right hand side by emergency services. Emergency services entered the aircraft with a hose and attempted to fight the fire from the inside of the aircraft as well as assisted in the passenger evacuation. While trying to liberate the pinned flight attendants emergency services observed fire coming in from the window/fuselage. The NTSB is probably going to release runway 28L to the airport within the next 24 hours. In an interview with Korean Authorities the pilot flying reported that a flash of light occurred at 500 feet which temporarily blinded him, the NTSB confirmed that this was mentioned in their interview as a temporary event, too.
On Jul 11th 2013 the NTSB reported in their final press conference, that the pilot flying described the bright source of light at 500 feet as a probable reflection from the sun straight ahead of the aircraft but not on the runway. Based on CVR: During the approach there were remarks in the cockpit about being high on the approach, then on the glide path and some time later being below glidepath. 35 seconds prior to impact the automated 500 feet call sounded, shortly afterwards the landing checklist was completed. 18 seconds prior to impact the automated 200 feet call out sounded, 9 seconds prior to impact the automated 100 feet call out sounded, immediately afterwards the first comment for speed was heard. There was no mention of speed between 500 and 100 feet. About 3 seconds before impact the call for go-around occurred. A second call for go-around was heard 1.5 seconds before impact, this call came from a different crew member. Flight control surfaces and engines appeared to respond normal to control inputs, there was no anomaly with autopilot or autothrust systems based on FDR data. The runway was released to the airport on Jul 10th, the airport began cleaning the runway. All passenger seats were inside the aircraft cabin, only 3 flight attendant seats were ejected from the aircraft with the flight attendants seated in them. A firefighter entering the aircraft via door 2L before the fire reached the cabin reported, that when he looked right the cabin and seats looked "pristine" as if the aircraft could just turn around and depart again, very little if any damage. The escape lighting was on during the evacuation and the PA system was available. All occupants had left the aircraft prior to the fire reaching the cabin. The floor of the aircraft from cockpit to main wing spar was sound, the support structure of the fuselage floor past the main wing spar was compromised at the right hand side, the left hand side was still sound. Between doors 3 and 4 the damage gets progressively worse, there is no floor aft of doors 4.
On Jul 8th 2013 South Korea's Ministry of Transport reported the captain (43, ATPL, 9,793 hours total) of the ill-fated flight was still under supervision doing his first landing into San Francisco on a Boeing 777, although he had 29 landings into San Francisco on other aircraft types before. He was supervised by a training captain with 3,220 hours on the Boeing 777, all responsibilities are with the training captain.
The NTSB opened their investigation docket containing several 1000 pages of documentations of the work of the various investigation groups, however did not release a preliminary, factual or final report as claimed by media and other aviation media, in particular there is no NTSB preliminary report taking any conclusions to autothrust system or pilot performance as claimed.
On Mar 31st 2014 Asiana submitted a 46 page document, looking like and easily confused with an official final investigation report, stating that the crew was conducting a high energy approach (from a high and fast posture). At 1600 feet AGL the flight director/autopilot changed to FLCH, however, none of the pilots recalled pressing that or related button, the automation went into go-around mode accelerating the engines for the go around and the autopilot going to acquire the go-around altitude. The pilot flying disconnected the autopilot, called "manual flight". As the aircraft was still high and fast, he pulled the thrust levers to idle, which changed the autothrust function from thrust to hold disabling airspeed protection and automatic wake up function. At 500 feet AGL the aircraft was on glide (PAPI two red, two white) at 135 KIAS 2 knots below VREF still within stabilized approach criteria. During the next 17 seconds the airspeed decreased to 118 KIAS and the aircraft descended to 200 feet AGL, the PAPI now showed 4 reds (below glide). 7 seconds later a quadruple chime sounded, the pilot flying advanced the thrust levers to go around and called "go-around", pitched the aircraft up by about 10 degrees, the engines however were still at idle and the aircraft continued to lose altitude - the stick shaker activated 4 seconds prior to impact - and impacted the sea wall about 11 seconds later.
Asiana complained: "In almost all situations, the B777’s autothrottle system supports stall protection and ensures that the aircraft maintains a safe airspeed. However, if a plane is in FLCH mode, the autothrottle will enter HOLD mode if: (1) the throttles are at the aft stop (i.e., engine is in idle); or (2) the throttles are manually overridden. In HOLD mode, the autothrottle is engaged (on), but it does not provide any input to the throttle levers or engines. The servos are disengaged from the throttle levers. Therefore, while the autothrottle is technically on, it is providing no service to the flight crew. ... Boeing makes clear that the autothrottle is an essential tool, stating that “[a]utothrottle use is recommended during all phases of flight,” including “[w]hen in manual flight.” ... In contrast to the repeated references to the comprehensive airspeed protection provided by the autothrottle system, the Boeing 777 FCOM contains only a single, one-sentence note which can be read to suggest that autothrottle will not support speed protection when in FLCH mode. The note reads: “When the pitch mode is FLCH or TOGA, or the airplane is below 400 feet above the airport on takeoff, or below 100 feet radio altitude on approach, the autothrottle will not automatically activate."
Asiana claimed that Europe's EASA identified the same autothrottle safety issue during certification of Boeing's Dreamliner 787.
Asiana proposed following conclusions to the final report:
The probable cause of this accident was the flight crew’s failure to monitor and maintain a minimum safe airspeed during a final approach, resulting in a deviation below the intended glide path and an impact with terrain. Contributing to this failure were (1) inconsistencies in the aircraft’s automation logic, which led the crew to believe that the autothrottle was maintaining the airspeed set by the crew; and (2) autothrottle logic that unexpectedly disabled the aircraft’s minimum airspeed protection.
Significant contributing factors to the accident were (1) inadequate warning systems to alert the flight crew that the autothrottle had (i) stopped maintaining the set airspeed and (ii) stopped providing stall protection support; (2) a low speed alerting system that did not provide adequate time for recovery in an approach-to-landing configuration; (3) the flight crew’s failure to execute a timely go-around when the conditions required it by the company’s procedures and, instead, to continue an unstabilized approach; and (4) air traffic control instructions and procedures that led to an excessive pilot workload during a high-energy final approach.
Boeing stated in their submission published on Mar 31st 2014 that at 130 feet AGL:
At this point, airplane pitch attitude was over 7 degrees and increasing. An electric seat motor is recorded on the CVR. Only the two pilot seats are electrically controlled, both fore/aft and up/down, the observer seat is not electric. Therefore, either the PF or PM had to adjust his seat at 130 feet on short final, likely because he was finding it difficult to see the PAPI due to the pitch attitude of the airplane.
The CVR recorded the sound of a quadruple chime eleven seconds before impact.
Reconstruction analysis performed by the NTSB and Boeing confirmed that the time the beeper sound was recorded on the CVR is consistent with the time the Engine Indicating and Crew Alerting System (EICAS) should have provided an AIRSPEED LOW alert.
No other caution alert is consistent with the data. The PF, in a post-accident interview, stated that he saw a text alert appear on the EICAS display, which may have read “AIRSPEED LOW.” The evidence thus shows that the chime recorded on the CVR was the aural alert for the AIRSPEED LOWalert. Three seconds after the AIRSPEED LOWalert, the throttle levers were advanced to full power and the PM called out “speed”. Based on the AFDS and autothrottle modes recorded on the FDR data, it is apparent that the thrust levers were manually pushed to full power, rather than by pushing the Take Off Go-around (TOGA) button. The engines began spooling-up immediately, but the normal engine spool-up time from approach idle to full power is seven to eight seconds.
The PF was applying several degrees of aft column to pitch the airplane up as the airspeed decayed (see Plot 5). Aft column input is usually not needed until commencement of the flare maneuver, which is typically commenced below 50 feet.
The FDR data also shows that no stabilizer trim was applied by the PF to relieve the force needed to pull the column. It is unusual for the pilot to have to pull back on the column in this manner, as pilots typically trim the aircraft. But no trim had been applied since the point the autopilot was disconnected more than a minute prior at 1,500 feet.
Also, since the airspeed had decayed below the minimum maneuvering speed, the pilots couldn’t trim the aircraft and the force required to pull the column aft was progressively increasing. The inhibition of the trim function and increased column forces, both of which occur below minimum maneuvering speed, are designed as tactile clues that the airplane is below the minimum maneuvering speed.
About five seconds before impact, the PF pulls the column to nearly full aft travel and the stick shaker activated.
Boeing continued their submission: "Asiana’s go-around policy states that the PF may initiate a go-around regardless of whether the PF is the captain or a copilot. But during a post-accident interview, the Trainee Captain (PF) stated that only the IP had the authority to decide to go-around. This confusion regarding who was responsible for calling for a go-around may have delayed initiation of a go-around."
Boeing stated with respect to the fatal injuries: "The three fatalities were assigned to seats 41B, 41E and 42A. A traveling companion seated in 41G confirmed that the passenger assigned to seat 41B was actually seated in 41D at the time of the landing. The companion also confirmed that, prior to impact, the passenger in 41E was not wearing a seatbelt, and the passenger in 41D was covered by a blanket, so seat belt status was not witnessed. The passenger seated in 41E was found on the ground forward of the left wing. The passenger seated in 41D was found fatally injured on the runway near the threshold and near the three flight attendants who departed the airplane. The passenger seated in 42A died six days after the accident. The injuries sustained by the passenger in 42A are consistent with the injuries sustained by the other two passengers who departed the airplane during the crash sequence, and it is likely this passenger was the second “critically injured” passenger found by the first responders near the runway threshold. The seatbelts in the seats occupied by the fatally injured passengers during the landing (41D, 41E, 42A) were all found unbuckled and were otherwise not damaged. Additionally, the seats remained in the last two seat rows of the airplane and were in the area where the most significant structural damage was sustained to the aircraft fuselage and cabin. Therefore, the three fatally injured passengers separated from the airplane during the crash sequence because they were likely not wearing seatbelts."
Boeing proposed following final conclusions to the investigation:
This accident occurred due to the flight crew’s failure to monitor and control airspeed, thrust level and glide path on short final approach. This accident would have been avoided had the flight crew followed procedures and initiated a timely go-around as the approach became increasingly unstable in relation to the stabilized approach criteria.
Relevant NOTAMS:
07/051 (A1331/13) - NAV ILS RWY 28L LLZ/DME U/S. 07 JUL 17:00 2013 UNTIL UFN. CREATED: 07 JUL 03:08 2013
07/048 - RWY 10L/28R CLSD. 06 JUL 23:10 2013 UNTIL UFN. CREATED: 06 JUL 23:10 2013
07/047 - RWY 10R/28L CLSD. 06 JUL 23:09 2013 UNTIL UFN. CREATED: 06 JUL 23:09 2013
07/046 (A1326/13) - RWY 28L PAPI U/S. 06 JUL 22:19 2013 UNTIL UFN. CREATED: 06 JUL 22:19 2013
07/045 (A1324/13) - AD AIRPORT CLSD. 06 JUL 20:10 2013 UNTIL UFN. CREATED: 06 JUL 20:10 2013 (cancelled at 23:09Z)
06/005 (A1056/13) - NAV ILS RWY 28L GP U/S. 01 JUN 14:00 2013 UNTIL 22 AUG 23:59 2013. CREATED: 01 JUN 13:40 2013
Metars:
KSFO 061956Z 23004KT 10SM FEW016 19/10 A2981 RMK AO2 SLP095 T01890100
KSFO 061856Z 21007KT 170V240 10SM FEW016 18/10 A2982 RMK AO2 SLP098 T01830100
KSFO 061756Z 21006KT 10SM FEW016 18/10 A2982 RMK AO2 SLP097 T01780100 10183 20128 51005
KSFO 061656Z VRB06KT 10SM FEW013 SCT018 17/10 A2982 RMK AO2 SLP096 T01670100
KSFO 061556Z 02003KT 10SM FEW012 SCT018 16/11 A2982 RMK AO2 SLP096 T01610106
KSFO 061456Z VRB03KT 10SM FEW010 SCT015 14/10 A2980 RMK AO2 SLP092 T01440100 51006
Video by ground observer Fred Hayes filming the entire landing sequence at:
Video of the aftermath by a ground observer (Video: SecretStoryExclu):
Scenes inside the wreckage (Photo: NTSB):
The flight data recorders arrived at the NTSB Lab in Washington (Photo: NTSB):
One of the engines (Photo: Reuters):
Detail of area ahead of threshold (Photo: Reuters):
Detail of sea wall (Photo: Reuters):
Aerial Overview of sea wall to final position (Photo: Reuters):
Aerial Overview of accident site (Photo: DPA/AP):
Debris ahead of the runway (Photo: AFP):
Aerial View of the wreckage (Photo: AFP):
The wreckage (Photo: AFP):
Passenger Photo (Photo: David Eun):
Map (Graphics: AVH/Google Earth):
http://avherald.com/h?article=464ef64f
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