SQ006 Investigation Report Commentary

Singapore Airways B747-400 Wrong Runway Take-off in Taipei

You will see that Taiwan does not entirely escape blame in the ASC report.

The reports by ASC and MOT are very thorough and leave no stones unturned in the above areas; lots of lessons noted and actions have been taken by both CKS and SIA to rectify the shortcomings .


Both approaches in investigations are correct .

But what alarmed me was the formatting of the Final Analysis of ASC which classified the Causal Factors as:

"(1) “findings related to probable causes” which identify elements that have been shown to operate or almost certainly have operated in the accident; ( please note the operative word: operated.)

In short the investigation of the causal factors relating to the accident, will be entirely focused on the Pilot and the weather, and deficiencies of airport system and other contributing factors were relegated to Risks.

As a result, the concluding "Probable causes" will, for all intents and purposes, always be on the weather and the pilot even before the ASC started its analysis of the Probable causes "

Even though Dr Yong Kay (the chairman) has qualified subsequently that Risk Factors play an equal and critical role as causal factors in the accident, whether we like it or not, it is only natural for both sides to adopt a "self-protection" mode in this investigation.

Not sure how long 05R had been inactive as a runway. I had heard rumours it was as much as 12 years! Is there any record of when the last time 05R was actually used for takeoffs and/or landings? How long have the Taiwanese maintained this hazard to operations, a taxiway marked as an active runway? Might as well put VASI's on Mt. Fuji.
 

Discussion
1. The Pilots failed to determine that the runway condition should have been classified as ‘contaminated’ due to the inevitable buildup of standing water under cyclone conditions. This determination would have downgraded the cross-wind limit for takeoff from 45 knots (wet runway) to 15 knots (contaminated runway) and therefore prevented the scheduled departure.

2. The Pilots' low-visibility taxiing performance was deficient during the final stage of taxi, and their navigation procedure was inadequate and did not utilize runway charts, signage, markings or cockpit instruments to guide them to the correct runway. The attention of the co-pilot Latiff and the relief pilot Ng was ‘inside’ the cockpit focused on the pre-takeoff checklist and calculating the cross-wind component. Only Captain Foong’s attention was ‘outside’ the cockpit focused on taxiing slowly in the slippery conditions and following the green taxiway lights to the runway.

3. The reason Captain Foong made a premature turn onto runway 05R was because:

i) he had the false impression that ATC could see the aircraft. He was under that impression because ATC issued his takeoff clearance just as he reached the end of the taxiway and was beginning his turn onto the runway. Co-pilot Latiff also confirmed that the timing of the takeoff clearance gave him the impression that everything was in order.

ii) The captain did not use the runway chart or the compass to guide him to the correct runway. Instead he stated that he “followed the green taxiway lights” despite the fact that this technique is not as per Heathrow and could/should not be used at CKS (where visual navigation is required).

iii) He also failed to notice signs, markings and lights which indicated he was turning onto the wrong runway. These included the green taxiway lights to 05L (which were more widely spaced than normal), a clearly illuminated 05R sign as he turned into the runway, and the 05R marking painted on the runway in front of him as he lined up for take-off. But the first link in the chain was that the FIRST taxiway green centre-line light leading across 05R threshold to the 05L runway was unserviceable. And the second light (on from the u/s one) was DIM. The first serviceable centre-line light was distantly 116m away (further on and across the far side of the 05R threshold). Yellow taxi-way centre-line markings did not continue across the 05R threshold (between the 05R piano-keys) – as required by ICAO. Only 4/16 centre-line (lead-on to 05L) lights, as required by ICAO, were provided (and two of those were u/s). So what Cpt Foong had instead, in his clearly-lit foreground, was a very seductive set of 16 closely spaced Centre-line green lights leading him onto 05R.

4. As they held for takeoff, all 3 pilots thought they saw a ‘normal runway scene’ and failed to recognize crucial indicators that they were on the wrong runway, including:

i) that the center runway lights were green and not white (a printout record from calibration and maintenance equipment showed that the center runway lights were on 4 minutes before the crash)  

ii) that it did not have touch-down lights or high-intensity runway edge lights (lack of evidence from security and passenger video, together with eyewitness testimony from the pilot of a plane on the taxiway 110m from the 05R threshold indicated that the runway edge lights were almost certainly off).

iii) that the runway was 15m narrower than it should have been

iv) that the PVD instrument had not unshuttered.

5. Several factors were speculated to have led to these navigational deficiencies and observational failures including that:

i) the pilots were accustomed to using runway 06 and had not used 05L for 2-3 years and were therefore unfamiliar with it.

ii) Although having read a NOTAM concerning the construction on 05R, the pilots had not read the SIA INTAM that contained important information on the status of 05R’s center and edge lights

iii) Captain Foong had not been officially trained in low-visibility taxiing

iv) The pilots all had an incomplete understanding of why the PVD did not unshutter and incomplete training on the operational context of its usage.

v) The green taxiway lighting that led to 05L was abnormally spaced and instead of being 7.5m apart, each light was 23m apart

vi)  All 3 pilots were fixated on taking-off quickly before the weather conditions deteriorated further and prevented takeoff (although there was no evidence of ‘organizational pressure’ on the pilots to depart on schedule that night).

6. The CKS airport authority was derelict in their maintenance and safety responsibilities. By not placing mandatory construction warnings at the entrance of 05R, they failed to address the risk that aircraft might inadvertently attempt to take off from a partially closed runway. They also failed to adequately maintain taxiway lights and marking to accepted international standards.


Maybe I am missing something, but this seems a pretty unbiased statement of facts. If you look at the NTSB comments in the appendix, they seem to think so too. Don’t be fooled by the spin doctors.

i.e. I think the wrong turn into 05R is not the BIG issue here. One can make a wrong turn (and I think this not as uncommon as one would have thought?) without the same disastrous outcome. i.e.:

a.  realize the mistake and turn out again, or

 
b. don’t realize the mistake but still take off from the wrong but operational runway ..... (safely!?).

The really big issue is being able to attempt take-off from a CLOSED (and wholly obstructed) runway. Some would insist that it was a PARTIALLY closed runway and therefore not technically 'CLOSED'. How is one supposed to make that distinction if the difference is only 'apparent' as you are passing 'V1'? Some would counter that the centre lights were not white and there were no touch-down lights and that the edge lights "were almost certainly off" that this was not a runway but a taxiway. Some will say that the PVD "had not unshuttered" hence this was a wrong runway. Then how come "all 3 pilots thought they saw a ‘normal runway scene’ " and thought they were on the correct runway? Look at this explanation here.

"Co-pilot Latiff also confirmed that the timing of the takeoff clearance gave him the impression that everything was in order."

However, if you look at the report, the elapsed time between clearance and start of the roll is relatively considerable… in the order of 80 seconds. Partly explained by the 5 kts taxi speed, I know.... but if their "ready" call was premature (clearly debatable), then ATC’s natural response to offer clearance (no traffic-and they can’t see them anyway) whilst still on taxiway NP might have induced the pilot to more readily accept the "lead-on" picture he saw at N1/05R intersection, given the time elapsed between the two. The longer the time-elapse is, the more willing he becomes to accept the notion that he is indeed on the correct runway.
If the takeoff clearance had only just been issued (later, during the turn into N1), the pressure to accept those compelling green lights might have been less.

Turning onto the wrong runway was the cause of the accident and the main issue here!

But equally, because humans are naturally fallible and indulge in secretive wishful thinking, the why and how that led the pilots into turning onto the wrong runway is what needs to be scrutinized.

From where I sit, the following issues are the main areas/factors:

The inclement weather,

The night environment,

Signage, lightings, markings of the taxiway and failure to obstruct entry into the 05R Runway

Air Traffic control : Low Visibility Procedures (LVP) taxy monitoring and issue of takeoff clearance.

Take off procedures of SIA: for confirmation of correct runway.

The TW report avoids unveiling the "golden nugget" and instead opts for a mish-mash of comments and diatribe on several elements that make up the whole.  Yes, an accident is usually the result of a chain of events but the "probable cause" theory is still the best way to go, in my opinion. What was the last chain in the link that made the accident inevitable? Turning on to the wrong runway is about as clear an error as you can get. However this obviously wasn’t the last link in the chain, although if the NTSB had been at the helm, you can bet your bottom dollar that this would have been their conclusion. I see that their recommendations centre almost entirely on developing cockpit moving-map nav displays for ground operations.