Going around with no thrust. Emirates B773 accident at Dubai on August 3rd, 2016, interim report

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Photo (C) Wojtek Kmiecik. JetPhotos.net. Photo ID: 8178250

United Arab Emirates, General Civil Aviation Authority, Air Accident Investigation Sector. Accident Preliminary Report: Runway Impact During Attempted Go-Around. Dubai International Airport. 3 August 2016. Boeing 777-300 operator: Emirates. AAIS Case No: AIFN/0008/2016

Occurrence Brief

Occurrence Category: Accident. Name of the Operator: Emirates.Manufacturer: The Boeing Company. Aircraft Model: 777-31H. Flight Hours/Cycles: 58169/13620

Type of Flight: Scheduled Passenger. State of Occurrence: The United Arab Emirates. Place of Occurrence: Runway 12L, Dubai International Airport. Date and Time: 3 August 2016, 0837 UTC

Total Crewmembers: 18 (two flight crew and 16 cabin crew). Total Passengers: 282. Injuries to Passengers and Crew: 24 (one serious, 23 minor). Other Injuries: One firefighter (fatal)

Nature of Damage: The Aircraft was destroyed

Notes:

  • Unless otherwise mentioned, all times in this Report are UTC time. Local time of the United Arab Emirates is UTC plus 4 hours.
  • The times stated in this Report are referenced to the flight data recorder.

Factual Information

1. History of the Flight

On 3 August 2016, an Emirates Boeing 777-300 Aircraft, registration A6-EMW, operating a scheduled passenger flight EK521, departed Trivandrum International Airport (VOTV), India at 0506 for Dubai International Airport (OMDB), the United Arab Emirates. At approximately 0837, the Aircraft impacted the runway during an attempted go-around at Dubai.

There was a total of 300 people onboard the Aircraft, comprising 282 passengers, two flight crewmembers, and 16 cabin crewmembers.

The Commander, seated in the left hand (LH) seat, was the pilot flying (PF), and the Copilot was the pilot monitoring (PM).

As the flight neared Dubai, the crew received the automatic terminal information service (ATIS) Information Zulu, which included a windshear warning for all runways.

The Aircraft was configured for landing with the flaps set to 30, and approach speed selected of 152 knots (VREF + 5) indicated airspeed (IAS). The Aircraft was vectored for an area navigation (RNAV/GNSS) approach to runway 12L. Air traffic control cleared the flight to land, with the wind reported to be from 340 degrees at 11 knots, and to vacate the runway via taxiway Mike 9.

During the approach, at 0836:00, with the autothrottle system in SPEED mode, as the Aircraft descended through a radio altitude (RA) of 1,100 feet, at 152 knots IAS, the wind direction started to change from a headwind component of 8 knots to a tailwind component. The autopilot was disengaged at approximately 920 feet RA and the approach continued with the autothrottle connected. As the Aircraft descended through 700 feet RA at 0836:22, and at 154 knots IAS, it was subjected to a tailwind component which gradually increased to a maximum of 16 knots.

At 0837:07, 159 knots IAS, 35 feet RA, the PF started to flare the Aircraft. The autothrottle mode transitioned to IDLE and both thrust levers were moving towards the idle position. At 0837:12, 160 knots IAS, and 5 feet RA, five seconds before touchdown, the wind direction again started to change to a headwind.

As recorded by the Aircraft flight data recorder, the weight-on-wheels sensors indicated that the right main landing gear touched down at 0837:17, approximately 1,100 meters from the runway 12L threshold at 162 knots IAS, followed three seconds later by the left main landing gear. The nose landing gear remained in the air.

At 0837:19, the Aircraft runway awareness advisory system (RAAS) aural message “LONG LANDING, LONG LANDING” was annunciated.

At 0837:23, the Aircraft became airborne in an attempt to go-around and was subjected to a headwind component until impact. At 0837:27, the flap lever was moved to the 20 position. Two seconds later the landing gear lever was selected to the UP position. Subsequently, the landing gear unlocked and began to retract.

At 0837:28, the air traffic control tower issued a clearance to continue straight ahead and climb to 4,000 feet. The clearance was read back correctly.

The Aircraft reached a maximum height of approximately 85 feet RA at 134 knots IAS, with the landing gear in transit to the retracted position. The Aircraft then began to sink back onto the runway. Both crewmembers recalled seeing the IAS decreasing and the Copilot called out “Check speed.” At 0837:35, three seconds before impact with the runway, both thrust levers were moved from the idle position to full forward. The autothrottle transitioned from IDLE to THRUST mode. Approximately one second later, a ground proximity warning system (GPWS) aural warning of “DON’T SINK, DON’T SINK” was annunciated.

One second before impact, both engines started to respond to the thrust lever movement showing an increase in related parameters.

At 0837:38, the Aircraft aft fuselage impacted the runway abeam the November 7 intersection at 125 knots, with a nose-up pitch angle of 9.5 degrees, and at a rate of descent of 900 feet per minute. This was followed by the impact of the engines on the runway. The three landing gears were still in transit to the retracted position. As the Aircraft slid along the runway, the No.2 engine pylon assembly separated from the right hand (RH) wing. From a runway camera recording, an intense fuel-fed fire was observed to start in the area of the damaged No.2 engine-pylon wing attachment area. The Aircraft continued to slide along the runway on the lower fuselage, the outboard RH wing, and the No.1 engine. An incipient fire started on the underside of the No.1 engine.

The Aircraft came to rest adjacent to the Mike 13 taxiway on a magnetic heading of approximately 240 degrees. After the Aircraft came to rest, fire was emanating from the No. 2 engine, the damaged RH engine-pylon wing attachment area and from under the Aircraft fuselage. Approximately one minute after, the Commander transmitted a “MAYDAY” call and informed air traffic control that the Aircraft was being evacuated.

Together with the fire commander, the first vehicle of the airport rescue and firefighting service (ARFFS) arrived at the Accident site within one minute of the Aircraft coming to rest and immediately started to apply foam. Additional firefighting vehicles arrived shortly after.

Apart from the Commander and the senior cabin crew member, who both jumped from the L1 door onto the detached slide, crewmembers and passengers evacuated the Aircraft using the escape slides.

Twenty-one passengers, one flight crewmember, and one cabin crew member sustained minor injuries, and a second cabin crewmember sustained a serious injury. Approximately nine minutes after the Aircraft came to rest, a firefighter was fatally injured as a result of the explosion of the center fuel tank.

Appendix A (to the full Report) illustrates the final flight path from over the threshold until the Aircraft came to rest.

emirates-773-accidented

Photo (C) Szabó Gábor. JetPhotos.net. Photo ID: 8246103

2. Details of Injuries

Crew members

The Copilot suffered abrasions to his elbow.

The senior cabin crew member required medical treatment and was hospitalized for five days as a result of smoke inhalation.

A cabin crew member, who evacuated using the R2 door escape slide, sustained blisters to her feet that required medical treatment.

Passengers

Out of the 282 passengers, 21 suffered minor injuries and were transported to different medical facilities.

Others

A firefighter from the ARFFS sustained fatal injuries during firefighting activity, and eight firefighters required medical treatment for minor injuries.

3. Damage to Aircraft

The Aircraft was destroyed due to impact and subsequent fire.

4. Other Damage

Runway damage

The initial impact of the aft lower Aircraft fuselage caused surface damage to the runway at two areas abeam the November 7 taxiway. The runway surface was scored as the Aircraft and engine cowlings slid along it.

Aerodrome lighting and signage damage

As the Aircraft slowed and then began to turn to the right, it impacted several aerodrome lights and signs which required replacement as follows:

  • Seven taxiway guidance signs (TGS) boards
  • Four taxiway centerline lights
  • Three taxiway edge lights
  • Two runway centerline lights
  • Three touchdown zone lights

Effect on the environment 

The Accident site was contaminated by Aircraft structure decomposition, firefighting fluids, and spillage of Aircraft fuel.

5 Flight crew information

Flight crew data
Commander Copilot
Age 34 37
Gender Male Male
Type of license ATPL1 ATPL
Rating M/E LAND, A330 (P2), A340 (P2), B777/787 M/E LAND, B777/787 (P2)
Total flying time (hours) 7457.16 7957.56
Total on this type (hours) 5128.20 1296.55
Total last 90 days (hours) 194.4 233.22
Total on type last 90 days (hours) 194.4 233.22
Total last 7 days (hours) 13.56 19.30
Total on type last 7 days (hours) 13.56 19.30
Total last 24 hours (hours) 3.59 3.59

6. Aircraft systems

During the landing and attempted go-around, the Aircraft was in a rapidly changing and dynamic flight environment. The initial touchdown and transition of the Aircraft from air to ground mode, followed by the lift-off and the changes in the Aircraft configuration in the attempted go-around, involved operational modes, logics and inhibits of a number of systems, including the autothrottle, the air/ground system, the weather radar, and the GPWS.

The characteristics of these systems, and others will be examined during the course of the Investigation.

7. Meteorological Information

A windshear warning was issued by the National Center of Meteorology and Seismology issued at 0735 and valid for the period from 0740 to 0900 and for all runways. This warning was broadcasted in ‘Information Zulu’ of Dubai International Airport ATIS at 0800.

In addition, the meteorological terminal air report (METAR) issued by the Dubai International Airport Weather Office Aviation Meteorology Section of the National Center of Meteorology and Seismology, on 3 August 2016, shows the weather condition for 0830 as follows: wind was from 110 degrees, 15 knots, variable between 60 and 150 degrees, visibility 6,000 meters, no significant cloud, temperature 48 degrees centigrade, dew point 6 degrees centigrade, barometric pressure adjusted to sea level (QNH) 993 Hectopascals, windshear on all runways, temporary wind from 350 degrees at 15 knots, visibility 4,000 meters and widespread dust.

A special METAR was issued at 0839 and showed the weather condition as follows: wind was from 120 degrees at 17 knots, visibility was 4,000 meters with widespread dust and no significant cloud. The temperature was 48 degrees centigrade, dew point was 6 degrees centigrade, QNH 993 Hectopascals with windshear on all runways. Temporary wind from 350 degrees at 15 knots and visibility 3,000 meters.

The terminal aerodrome forecast weather (TAF) issued on 3 August 2016 at 0505, and valid from 0600 of 3 August to 1200 of 4 August, showed the following forecasted information:

TAF OMDB 030505Z 0306/0412 08008KT 7000 NSC BECMG 0308/0310 36012KT BECMG 0314/0316 09008KT PROB30 0404/0411 09016G26KT 3000 DU PROB30 0410/0412 01012KT

The report indicated that the wind would be from 080 degrees at 8 knots, visibility 7,000 meters, no significant cloud, a gradual change in wind conditions to 360 degrees 12 knots was expected, beginning 0800 and ending 1000. The gradual change was expected to occur at an unspecified time within this time period.

The TAF continued with a change, which was forecasted to commence on the 3 August at 1400 and be completed by 3 August at 1600. Wind direction was anticipated to be from 090 degrees at 8 knots with a probability of 30 percent during the period between 0400 and 1100 of 4 August, the wind direction to be from 090 degrees at a speed of 16 knots gusting up to 26 knots and prevailing visibility 3,000 meters in dust. Moreover, there was a probability of 30 percent during the period between 1000 and 1200 of 4 August, wind direction from 10 degrees at a speed of 12 knots.

Table 5 illustrates the winds recorded at various locations at the airport, at the time of the Accident.

emirates-table-5

8. ATC communication

During the period from 0800 to 0827 (10 minutes before the impact), 16 aircraft landed normally. At 0829 and 0831, two aircraft performed go-arounds. This was followed by another two aircraft that landed normally immediately before the Accident flight.

At 0831, the Dubai air traffic watch manager (WM) called the air traffic coordinator (COD) and informed him of the unusual wind conditions. The WM informed the COD that there had been two missed approaches and that a windshear warning had been issued on the ATIS.

At 0835 the approach controller and the WM discussed the current wind conditions in relation to the runway in use. At the time of the discussion, the surface wind displayed indicated a tailwind component on runways 12L and 30L (the alternative landing runway). The lowest indicated tailwind component was 8 knots on runway 12L (the landing runway). Both the Approach controller and the WM remarked on these wind conditions as being strange. Both agreed that runway 12L was the best option at that time.

At 0837:28, the air traffic control tower issued a clearance to EK521 “…continue straight ahead climb four thousand feet.” At the same time, the approach controller called the WM to inform him that air traffic control radar would start the process of changing runways. Ten seconds later, the Accident occurred.

9. Flight Recorders

The Aircraft was equipped with a digital flight data recorder (DFDR) and cockpit voice recorder (CVR).

During the Aircraft recovery, both flight recorders were found in the rear galley area but still attached to the original mounting trays, with signs of prolonged exposure to elevated temperatures. The damaged flight recorders were sent to the AAIB facility for data retrieval in the presence of AAIS investigators.

Both memory modules were removed from the recorders. Optical microscope examinations were performed on the memory modules including the recovery of the memory unit information cables, prior to performing the download and readout. After the serviceability of the memory modules had been established, they were attached to a new chassis allocated for each recorder in order to download the data. Data from the DFDR and CVR was successfully downloaded and read out.

The examination of the DFDR and the CVR data showed that the recorders continued to record for a short period after the runway impact. The Investigation found that this portion of the recorded data was either invalid or missing information.

10. The Wreckage and Impact Information

The point of impact of the Aircraft with the runway was approximately 2,530 meters from runway 12L threshold, adjacent to the November 7 taxiway. Marks on the runway indicated that the Aircraft slid for approximately 800 meters along the runway with the three landing gears not fully up. The Aircraft came to rest adjacent to the Mike 13 taxiway, having turned to the right onto a heading of approximately 240 degrees.

The Aircraft aft fuselage lower section impacted first, followed by the engines, the lower section of the aircraft belly fairing, and then the forward fuselage and nose landing gear doors. The No.2 engine separated, moved laterally on the right wing leading edge, and remained near the right wing tip until the Aircraft came to rest.

As it slid along the runway surface, various components detached from the Aircraft. These components included portions of the engine cowlings, secondary support structures and parts of the wing to body fairings, access panel doors, and systems components. (Figure 1).

When the Aircraft came to rest, the primary structure was intact with the exception of the No.2 engine pylon assembly which had separated from the RH wing attachment.

emirates-fig-1

Figure 1 Aircraft Initial impact and final position

11. Medical and Pathological Information

Post-accident blood tests did not reveal psychoactive materials that could have degraded the crew performance

12. Cabin safety and evacuation

All of the cabin crewmembers stated that the flight was normal with some turbulence during the final part of the landing. Cabin crewmembers seated towards the rear of the Aircraft indicated that they thought the main landing gear contacted the runway only for the Aircraft to become airborne again until it impacted the runway.

The cabin crewmember at the L1 door reported that during the impact, her seat base broke and folded downwards. The senior cabin crew member, sitting opposite her, confirmed that the cabin crew member was hanging in her seat harness after the impact. He also noticed that the cockpit door had swung open. The cabin crewmembers at positions L1A and R1A reported that their seats had moved forward during the impact, and the cabin crewmember at the R5 door reported that a cabin panel had detached and fell in front of the door exit. The window blinds in first class had moved to their closed position during the impact.

Several passenger oxygen masks deployed after the impact. Preliminary Accident

After the Aircraft came to rest, the Commander announced “Attention Crew at Stations” via the passenger announcement system. Shortly after, he commanded the evacuation of the Aircraft.

The cabin crewmember at the L1 door was unable to open the door and requested assistance from the senior cabin crew member and the cabin crewmember from the R1 door. Together they were able to open the door and the escape slide deployed but detached from the Aircraft. The cabin crewmember consequently blocked the L1 door.

A cabin crew member opened the R1 door and the escape slide deployed automatically. During the deployment, the slide was blown up by the wind and blocked the exit. As a result, the cabin crewmember blocked the door. At a later time during the evacuation, this slide settled on the ground and became available for some passengers and crew. The door was again blocked as the slide deflated.

The L2 door required two crew members to open. The slide deployed automatically but did not touch the ground. The cabin crewmember consequently blocked the door. The slide was blown up against the door afterward, preventing any evacuation attempt through this door. No passengers or crew evacuated via this exit.

The R2 door was opened by a cabin crew member and the escape slide deployed automatically. There was a lot of smoke in the area of that door and the cabin crewmember redirected passengers to another door. When the smoke cleared, passengers and crew evacuated through that exit.

The cabin crewmember at the L3 door did not attempt to open the door as there was smoke outside. She blocked the door and redirected passengers to the R2 door.

The R3 door was opened, but the cabin crewmember noticed fire outside and she blocked the door while two passengers assisted in closing the door. She redirected passengers to the aft of the Aircraft.

The cabin crewmember at the L4 door opened the door and the slide deployed automatically. The slide was immediately blown up against the Aircraft, which resulted in the cabin crewmember blocking the L4 door.

The cabin crew member at the R4 door did not hear the “evacuate” instruction because of the noise level in the cabin, but she opened the door after she observed the L4 cabin crewmember opening her door. Several passengers evacuated from the R4 door, but they became stuck on the slide because it was filled with firefighting water. As a consequence, the R4 cabin crewmember redirected the other passengers to the R5 door.

The L5 door cabin crewmember opened the door and the escape slide automatically deployed. Initially, some passengers evacuated using this slide, but towards the end of the evacuation, the slide was blown up against the door preventing further evacuation.

The R5 door cabin crew member opened the door and the escape slide automatically deployed. However, the slide was lifted off the ground by the wind. As a result, the cabin crew member redirected passengers to the L5 door. A firefighter noticed the problem and held the slide down allowing the cabin crewmember to redirect passengers to the R5 door for evacuation.

The Commander and senior cabin crew member were the last to exit the Aircraft. They stated that they were still searching the cabin for any remaining passengers. When the center fuel tank exploded, causing intense smoke to fill the cabin, they attempted to evacuate from the cockpit emergency windows. However, as the cockpit was filled with smoke, they were unable to locate the evacuation ropes. Consequently, both evacuated by jumping from the L1 door onto the slide laying on the ground.

Table 8 summarizes slide usability during the evacuation.

emirates-table-8

emirates-1

This photo was taken from Malaysian Wings Forum page.

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This photo was taken from The Aviation Herald

13. Go-around procedure

The current flight crew operating manual (FCOM) and the flight crew training manual (FCTM) used by the Operator contained go-around procedures and the applicable training guidance.

The FCOM systems description under the heading Automatic Flight – Go-Around, chapter 4.20.17, (appendix B to this Report), states that “Pushing either TO/GA switch activates a go-around. The mode remains active even if the airplane touches down while executing the go–around.” In addition, the FCOM states that “The TO/GA switches are inhibited when on the ground and enabled again when in the air for a go–around or touch and go.”

The FCOM normal Go-Around and Missed Approach procedure, chapter NP.21.56, (appendix C to this Report), describes the actions and call-outs required by the PF and the PM.

In the FCTM under the heading Rejected Landing, chapter 6.28, it is stated that the FCOM/QRH does not contain a procedure or maneuver titled ‘rejected landing’ and the requirements for maneuver can be accomplished by doing a go-around procedure if it is initiated before touchdown. The following is stated in the FCTM:

“Rejected Landing

A rejected landing maneuver is trained and evaluated by some operators and regulatory agencies. Although the FCOM/QRH does not contain a procedure or maneuver titled Rejected Landing, the requirements of this maneuver can be accomplished by doing the Go-Around Procedure if it is initiated before touchdown. Refer to Chapter 5, Go-Around after Touchdown, for more information on this subject.”

The FCTM under the heading Go-Around and Missed Approach – All Engines Operating, chapter 5.67, states that the go-around and missed approach shall be performed according to the Go-Around and Missed Approach procedure described in the FCOM. The FCTM also states that “During an automatic go-around initiated at 50 feet, approximately 30 feet of altitude is lost. If touchdown occurs after a go-around is initiated, the go-around continues. Observe that the autothrottle apply go-around thrust or manually apply go-around thrust as the airplane rotates to the go-around attitude.” Below this statement, there is a note which states that “An automatic go-around cannot be initiated after touchdown.”

The FCTM Go-Around after Touchdown, chapter 5.69, states that:

“If a go-around is initiated before touchdown and touchdown occurs, continue with normal go-around procedures. The F/D [flight director] go-around mode will continue to provide go-around guidance commands throughout the maneuver.

If a go-around is initiated after touchdown but before thrust reverser selection, continue with normal go-around procedures. As thrust levers are advanced auto speedbrakes retract and autobrakes disarm. The F/D go-around mode will not be available until go-around is selected after becoming airborne.”

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Photos from Bureau of Aircraft Accidents Archives B3A

Ongoing Investigation Activities

The Investigation is ongoing and will include further examination and analysis of:

  • Aircraft performance
  • Aircraft technical and engineering
  • Operator policy, procedure, management, and organization
  • Air navigation service provider policy, procedure, management, and organization
  • Airport airside operations, and rescue and firefighting services
  • Meteorology
  • Any other safety aspects that may arise during the course of this Investigation.

The Investigation will carry out in-depth analysis of:

  • Contextual factors
  • Human factors
  • Organizational factors.

Source

1. United Arab Emirates, General Civil Aviation Authority, Air Accident Investigation Sector. Accident Preliminary Report: Runway Impact During Attempted Go-Around. Dubai International Airport. 3 August 2016. Boeing 777-300 operator: Emirates. AAIS Case No: AIFN/0008/2016

************************************

What leads expert, conscientious pilots to go around not ensuring they have the proper thrust?

  • Unnoticed autothrust disengage?
  • Overreliance on automation?
  • Not fully understanding of complex automation?
  • Training deficiencies?
  • Fixation and distraction? (The wind speed and direction/the windshear alert)
  • Complacency?
  • Expectation bias?
  • All of the above?

… Human Factors at it best

On the other hand, it will be interesting to see the safety recommendations regarding de cabin safety and evacuation aspects.

*******************

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