The 3 August Emirates Boeing 777 crash at Dubai may have happened a while ago, but the man/machine interface implications are so complex it still has human factors experts’ heads spinning.
Following an uneventful final approach to runway 12L the aircraft hit the runway with its gear in the retraction cycle, slid to a halt on its belly and burst into flames. All on board got out alive before the fire destroyed the fuselage, but a firefighter was killed by a fuel tank explosion.
That’s a surprising outcome for a serviceable aeroplane carrying out a normal landing at its home base.
So what happened?
Flight EK521 was inbound from Thiruvananthapuram, India carrying 282 passengers and 18 crew. The ambient temperature was high, nearly 50degC, and there was a windshear warning on all runways, but this did not cite high winds or powerful gusts. Probably the wind was swinging around under the influence of vertical air currents generated by intense surface heating combined with the coastal effect.
When the 777 had about 5nm to go on approach to 12L ATC cleared it to land and told the crew the surface wind was 340deg/11kt. That’s a touchdown-zone tailwind.
As the aircraft descended through 1,100ft on final approach the aircraft was also registering an airborne tailwind. It persisted almost all the way down.
But apart from the tailwind on the aircraft’s approach, the descent was uneventful until just before touchdown. At that point the tailwind switched to a headwind, adding about 20kt to the 777’s airspeed.
Around 5sec after the flare the right gear touched down about 1,100m beyond the threshold, and 3sec after that both main gear touchdown switches were made and the RAAS (runway awareness advisory system) voiced the alert “long landing, long landing”.
Questions still remain about exactly what happened next on the flightdeck. Who did what, and why?
The United Arab Emirates General Civil Aviation Authority has released some factual information about weather and aircraft performance, but the investigators are expected to take another three months or so to ready their final report.
Meanwhile from what the GCAA has released, we know that the captain was the pilot flying. He disconnected the autopilot at about 900ft on approach but left the autothrottle in. When he began the flare at 35ft AGL the throttles retarded to idle, and within about 10sec both touchdown switches had been made.
What happened next, or at least why it happened, is difficult to work out.
Witnesses say the aircraft “bounced” from the first touchdown. But the crew was attempting a go-around – possibly prompted by the “long landing” alert mentioned earlier – so the “bounce” may have been the result of the crew pulling the nose up for a go-around.
Some 4sec after the warning the aircraft was airborne again, the crew reduced the flap setting to 20deg, and 2sec later selected the gear up, both acts part of a go-around drill.
But the throttle levers remained at idle.
About 5sec after the aircraft had become airborne the tower, noticing the apparent intention, cleared the aircraft straight ahead to 4,000ft, and the crew read that back. Then the first officer called “check speed”, the throttle levers were moved from idle to fully forward, and the autothrust transitioned from idle mode to thrust mode.
Unfortunately the increasing engine power arrived too late to prevent the aircraft sinking back onto the runway with its gear almost fully up. It slid on its belly for 800m before coming to rest with the right engine detached and a fire under that wing.
The GCAA interim report doesn’t mention whether or not the crew attempted to trigger go-around power by selecting the TO/GA (take-off/go-around) switches at the time of the go-around decision, but it appends a page from the flight crew operating manual about autothrust modes. It contains this sentence: “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.”
This situation raises questions galore. In a go-around situation the drill is to select power first, then set the appropriate flap, then register a positive rate of climb and pull the gear up. Maybe the crew thought activating TO/GA was enough, but they didn’t monitor engine power, throttle lever movement or rate of climb before retracting the gear.
This is basic stuff, so what’s going on here?
Are we witnessing the actions of a crew rendered insensitive by automation, or de-skilled by the same thing? Or is this an event involving mode-confusion because of the complexity of modern aircraft and their smart control systems?
The industry is going through a crisis of confidence in pilot training. The doubt arises from increasing numbers of accidents that began with a non-critical fault or distraction and result in the pilots becoming startled and not acting as they had been trained to do.
Behind it all is the fact that today’s aircraft and their systems are impressive and reliable, but ultra-complex. Meanwhile the basic approach to pilot training is the much the same at was in the pre-digital era.
Emirates is in the vanguard of modern attitudes toward evidence-based training, but maybe the fundamentals are set before pilots reach the line.
Finally, pilots are never really trained to operate the digital systems they use all the time at work. They just learn that on the job.
Let’s go back a bit to the quote from the Emirates 777 FCOM: “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.”
I bet the pilots never tried that in the simulator.
Modern aeroplanes now are rather like personal computers in the relationship pilots have with them: most people are skillful users of tablets or laptops for routine tasks, but never have a chance to try out their full capabilities, most of which would rarely be needed. But if things go wrong or something unusual happens, the user is often out of his depth.
The Royal Aeronautical Society is hosting its two-day International Flight Crew Training Conference in London next week. This is one of the subjects that will be examined there.
5 thoughts on “Lessons from Dubai”
I put my signature underneath. But as a Boeing instructor I swear both the TO/GA function fail and simulator touch and go training including reselection of TOGA when airborne is part of Boeing Training Standards (may vary IAW Carriers though)
1. SITAW tail wind on approach you do not leave 1100 m behind you.
2. EK company culture, not allowed to fly manually, no visuals allowed always autopilot on. EK gives extra Sim session to practice manual visual approaches not permitted on daily flights, Why not the freedom to do so on line when weather permits. Reports needed to be filed and explained for long landing registered call out, was it really a required GO/A with remaining RWY ahead. The fear of doing something not according EK strict standards & regulated flying drove them to do the GO/A.
3. Rushed GO/A, 5 sec airborne Thrust set and checked, Flaps set for GO/A, positive climb checked gear up and already listening to ATC then find it more important to read back ATC clearance than check the above has been done correctly, why the rush?
4. The bigger the plane the slower it is to react to inputs why the rush?
The rush is because the fear of doing it wrong, the fear of FDM and reporting explaining the lack of thous basic flying skills which companies like EK forbide pilots to do on line.
The confidence has gone from the pilots to take over, because they are not allowed to and the fear of explaining why the auto pilot was not used as according to SOP when something comes up on the FDM which registers so many aspects of the flight.
This is self induced by today’s airlines by over automating the whole flight not allowing or trusting pilots to fly manually and using flight safety FDM as a tool to punish strike fear into pilots for not following strict SOPS that forbide so much.
“The 3 August Emirates Boeing 777 crash at Dubai may have happened a while ago, but the man/machine interface implications are so complex it still has human factors experts’ heads spinning”.
A while ago ?, that’s our-last month’s- life’s ticking clock; “En attendant Godot”, as Samuel Beckett said. Head spinning ?, I haven’t done that since my CPL days in Norman, Oklahoma in 1995. Halcyon days then to a yawning, without yawing or spinning- day yesterday on B-773ER/B-2006 operating CCA933 from ZBAA’s RWY36R to LFPG’s RWY27R in 09HRS 39MINS; with a couple of pedestrian step-climbs. And with a Paris “Journée sans voitures”,so,TGV trip to Bruxelles thereafter; read your Dubai-take enroute.
And very well conveyed of the writing of Savas Uskent and Ivor Felton of Sept 24 2016 too. Never truer words written of the non-just culture of the Gulf convoy to Doha, Dubai and Abu Dhabi. In the UAE: rules rule by law of the ruled brand; not generally of law by prevailing particular statute. Officially denied of course. But never believe anything until officially denied.
There is a fair trial before the hanging of auto-resignation at least. Best previous examples were EK407, operated by an A-345 on March 20 2009, from Melbourne to Dubai. And QR778, operated by a B-773ER on Sept 15 2015, from Miami to Doha. Still, the UAE’s GCAA’s AAIS is to be objectively commended for such a valuable report -in a while’s month- against vested interests.
QR778 Narrative: September 15 2015
EK521’s transition from touchdown to slamdown was 21 seconds elapsed for a 13 year old B-777-300, non ER of RR powerplants. Thereafter 33 seconds to smoking rest and 9 minutes additionally to fatal CWT explosion migrating a 45FT inboard upper wing skin section. A jet aviation first; and on video too. And with Nitrogen Generation System/NGS shutdown at touchdown. The CWT explosive dynamics will have greater prominence in the final report.
To wit: UTC chronology of EK521.
08:36:22 @ 700FT RA: @154KTS IAS, it was subjected to a tailwind component which gradually increased to a maximum of 16KTS.
08:37:06 @ 35FT RA: @ 159KTS IAS, Flare Commenced by PF- PIC.
08:37:09 @ 25FT RA: A/T transitions to IDLE mode – A/T is interactive in SPD mode, dual or single engine. Had the PF pushed or pulled the levers, the A/T would disengage in the “IDLE” mode. Absent that, T/R is the normal A/T disengagement, apart from the throttle’s side thumb/pinkie disconnect switches. Unlike the A/T gaps on the B-744, the A/T is ALWAYS -SOP- ON in the B-777/748(3 engines)/787. In SPD interactive it will move as pushed or pulled -for a faster response. Very useful in transiting a Windshear, for example. A hand push/pull is lot quicker than dialing in a speed upon opening the MCP’s window. Thereafter it will assume its previous “non-HOLD” position in SPD mode; be it FMS managed or MCP open window, “speed intervene”. In THR REF/ THR mode it is HOLD transposable. If switch disconnected, it will “WAKE UP” to the Pitch mode’s A/T coupling of SPD or THR REF, when the speed on the PFD’s tape is 10KT into the amber band of dereliction. In short; human-concentric AUTO-MAN-ATION.
08:37:12 @ 5FT RA: Flare-Float (5 seconds) with previous 16KT TWC, changing to 9KT HWC.
08:37:17 RH MLG on Ground from Flare-Float.
08:37:19 EGPWS-RAAS annunciates: “LONG LANDING, LONG LANDING” (audible caution ADVISORY).
08:37:20 LH MLG on Ground @ 162KTS IAS from a Target of 152KTS IAS(VREF +5KTS). RWY Wind 315 @ 9KTS/Gust 29KTS.
08:37:21 TO/GA left paddle trigger, tapped -apparently- by PF with rotation (TO/GA inhibited from 2 seconds after 5FT RA to 5FT RA for 2 seconds).
08:37:23 G/A Airborne after touchdown – Speedbrake/Spoilers auto-retract and Autobrakes disarm; for bounced landing and G/A protection.
08:37:27 Flaps 20 selected-10 seconds transit.
08:37:30 Gear Up selected-10 seconds transit.
08:37:31 @ 85FT RA:TOD-Gear retraction drag with IDLE thrust. IAS @ 134KTS- F/O called out “Check speed”.
08:37:35 Thrust levers moved -by hand- fully forward to the quadrant’s stops.
08:37:37 Thrust responds and EGPWS annunciates: “DON’T SINK, DON’T SINK”.
08:37:38 Aft fuselage impact on Runway 12L, abeam N7 intersection @ +9.5 Degrees Pitch-up @ -900FPM V/S @ 125KTS IAS.
If the above happened to an A-333, it -the accident- most likely would not have happened, because to Airbus TO/GA, requires an arm stretch from A/THR 0 -CL- FLX/MCT – TO/GA. That’s a 3 click detent PBW arm stretch. A contrast from the FBW full-stop, full stab trim travel possible with an effortless wrist twitch of the sidestick in ALTN LAW. Best illustrated on AF447’s A-332 on June 1 2009 and Indonesia AirAsia Flight 8501/ A-322 (QZ8501/AWQ8501) of December 28 2014. Same movie, different cinema. Ironically with Airbus, the A/T forces one to hand move them after takeoff to the CL detent to activate the stationary A/T. And what look like TO/GA paddles on an Airbus, are in fact T/R triggers to be finger-pulled rather than tapped. Boeing and Airbus: “Never the twain shall meet”.
In a balked landing -de facto emergency or perceived emergency- evasive manoeuvre, at least stretch an arm to avoid a finger-tapping trip into the TO/GAp is prudent…It is only as foolproof as the better fool turning base leg to final. It is good not God; and makes the idiom of “Keeping one’s hand in”, never more apt.
This accident is nearly as invaluably instructive as the Asiana 214 B772ER crash-landing, ground loop pirouette of 330 degrees to the left (EK521 only managed a mere 120 degrees to the right) on Sat July 6 2013 @ 11:28PST…That was 18 years of uneventful man-machine interface of B-777 flight operations FLCH’d up A/T HOLD in 83 seconds. With the PM PIC Instructor in the right seat adjusting his seat to attain a better view of the PAPI and obvious impending crash at 130 FT RA with 12 seconds to impact as the plane’s pitch attitude rose to 7 degrees and increasing. No thought of pushing the nose forward to aid the wing’s respiration; rather the opposite, in exhibiting an AF447, with muscular effort. The deferential F/O’s calls from the supernumerary seat were ignored. The CRZ captain was sitting in business class. His -typical Korean- militant union mandated that for him to be a flightdeck-seated “safety pilot”, a salary increment was mandatory. For myself, CRM 101: “One should not need an increment to avoid excrement”. A total lack of basic airmanship from all 4 crew members CAVOK-Severe Clearly-exhibited, beyond parody. Park Tu-soon; Wei Tu-soon.
If the A/T could speak it would have said: “You FLCH’d me to go to 3000FT, I then transitioned from V/S-SPD to FLCH SPD-THR mode to meet this demand. You then hand-pulled me to the idle stop. I am Good, not God; so I transitioned into HOLD mode as registered and clearly advertised on the PFD’s FMA. So, until you make up your FLCHing mind as to what you want, I am HOLD(ing) my position and I suggest you HOLD me, where you held me, until you push me back to THR. That will take about 8 seconds to spool-up from Flight Idle; by the way”. The PM-PIC did so @12 degrees pitch-up @ 103KTS IAS, 8 seconds before hitting the sea wall @ 105KTS IAS, as the P&W’s spooled up fully in, er, 8 seconds, not to mention pulling-not pushing-into the stickshaker. Coincidently, the last production B-772ER was delivered to Asiana on July 26 2013. Performance-wise it is equivalent to a B-773, non-ER.
The NTSB Tragedy Narrative: July 6 2013
Fox Noise affiliate: KTVU of Fox Noise in Oakland, bears unwitting half-witted witness to the truism of time being the difference between tragedy and comedy: The KTVU comedy on Friday @ 12:00PST on July 12 2016.
KTVU, got the ethnicity wrong for an Asiana, sorry, Asian stereotype. It should of course have been “Park Tu-soon”. As I always state in CRM seminars: “Clearly CRM is non-applicable at “too good an exclusive to check”, Fox Noise’s KTVU of Oakland. If it was,Tori Campbell would have realized that there was Sum Ting Wong, long before she landed on Ho Lee Fuk!”
The end result of EK521 bears not just an uncanny external resemblance-letting aside an oil fire and fuel fire accelerated CWT fatal explosion.
Taking RAAS as a “warning”, rather than an “advisory”, leads to flights of fancy, like EK19 of Mar 26 2016. Quite incredible in itself of abrogating decision-making to the RAAS.
On Nov 16 2011 AF471 had a serious GA-LOC. It dovetails into the slot between Asiana and Emirates. And happened long before them. All the crew had to do was set the minima at CATIIIA minima of 50FT RA, rather than the CATIIIB minima of 20FT RA. So when the Autoland status reverted to >LAND 2LAND 2< was not broken; it did not need fixing.
This was a crash-landing in all except outcome. So, Air France does not confine its mishandling to Airbus at least; it is surprising that the SNPL did not stage a strike action for this with demanding a bonus for the crew for rescuing their self-stricken aircraft, if French ATC did not ground them first with their own strike. Actually, that might not be a mutually bad idea, as the world bypasses French airspace. That the BEA can produce such objective reports against vested interests -like the GCAA’s AAIS too- enhances confidence in the transparency of aviation as an industry.
Click to access f-pp111116.en.pdf
Taking Air France-2011, Asiana-2013 and Emirates-2016; there is one triple conclusion to conclude. That is: on a B-777 a crewmember has to make a serious hand-held effort to keep their hand in, to kill themselves or others in attendance of conflagration thereafter. Emirates in general and Asiana in particular illustrate blind-sided book stupidity of rule by law, of the brand.
On July 8 2016 at Boeing-London Gatwick’s B-777-300 sim PT, I did “bet” on such a scenario. To wit: Normal ILS approach-landing, then F/O suddenly Incapacitated, then a TO/GA tap to G/A-go around due to a simultaneous runway aircraft incursion. I never thought about the TO/GA tap, as I TO/GA tapped and “muscle-memory”, pushed the throttles forward with my right hand simultaneously. By nature, I am a biceps/triceps stretcher, rather than a “digital arrector pili” stretcher.
This is from my DNA automotive driving habit of one hand on the steering wheel and the other on the gear stick; rather than any aeromotive CRM training, per se.
My sim TO/GA tap failed, but I thought nothing of it until August 3 2016’s EK521’s TO/GA-fail, OMDB’s RWY12L slamdown. We don’t fully understand all that we know. On the line, I fly manually -all engines- to flaps up and from “Gear Down/Flaps 20” too generally. Keeping FDM within peripheral reason, therein, on or after. My “hand-in”, is primary, until the 3D weather is G/A; as in Global Automated. Airbus make a good attempt at this “Auto-Wx” with its ATC friendly; “Ground Speed mini” function.
Click to access AirbusSafetyLib_-FLT_OPS-ADV_WX-SEQ02.pdf
Looking forward to the RAS take on RAAS this week, as you mentioned. Here’s to Sir Tim Clark of Birmingham, UK. Aided and abetted by Sheikh Ahmed bin Saeed Al Maktoum. Or is that the other pirouette way around ?
“Some 4sec after the warning the aircraft was airborne again, the crew reduced the flap setting to 20deg, and 2sec later selected the gear up, both acts part of a go-around drill.”
No airline that I’m aware of as of the date of this accident trains in the B-777 or widebodies etc…AFTER the main gear have touched down to perform a go around. -It’s all done prior due to the high workload and hazardous conditions that may be associated with doing it that late. That is to say the WHEELS MAY TOUCH the runway after a go-around is commanded (this is normal due to the time it takes for engines to spool up and the time for aircraft’s momentum to change. Therefore, please note that in this case, this is not a drill that is practiced in training as you’ve implied.