JAL incident at Haneda Airport
It is a miracle that there was not a heavy loss of life in this case.
I've commented a number of times on the evacuation for a simple reason, any assumption that a fire condition is not time critical would be ill advised to develop. There is only one place to be when the aircraft is on fire, and that is outside and well away from the conflagration. Having a CFRP airframe should not give excessive comfort that additional time exists to evacuate. The reports annexes will be worthwhile reading. In this case, no one on board the A350 had any awareness that their aircraft was about to be consumed by fire, up to the moment of impact, so when the cabin crew provide the opportunity to watch to their safety presentations, read their safety cards and review your own expected exit strategy from the aircraft, it really only matters if there is a desire to live another day.
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RH engine, (#2) is continuing to run, The fan blades have been destroyed, the stairs and the station 2.1 inlet is visible. There is visible rotation of the spinner. The ejecta of debris is faster than the surrounding smoke flow, they are under an accelerated mass flow, so consider the engine remains running. The E&E bay has been damaged so a failure of interfaces from the fuel control switches and fire switches to the FCU and FWSOVs is not impossible, and is similar to the AF072 B744 issue, and the EY A340-600 at Toulouse as has been indicated previously. The World DC10 was a different issue but is one of the prior "unable to shutdown" engine cases along with QF031 A380 #1 engine case at WSSS after the turbine oil fire/disk failure of #2 engine. The A340 and B744 cases were from E&E bay damage, which this case has also had.
So everybody might have been doing their utmost to keep things moving as swiftly as possible...until.....
Last edited by DIBO; 5th Jan 2024 at 23:57. Reason: typo
Spare a thought for the on duty air traffic controllers. Likely handled hundreds of movements successfully and probably prevented many accidents and close calls with early intervention and correction of misheard or misread instructions in their careers. But miss one runway incursion. I can imagine how they must be feeling.
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The information that is starting to come out is suggesting that the original times that were given for evacuation were erroneous. At 7 minutes, the person behind the LH wing station has started to move to egress, and the video that they have taken shows that there is no mass of people in front at that time. More than half of the pax are already off the aircraft by that time. The aircraft comes to rest around 30 seconds into their video, so that is at around 6:30 since coming to a halt. The assertion of 8 minutes to start and 18 minutes to conclude is less than accurate. That the PIC re-entered the aircraft after egress (if correct) and then found pax in the otherwise empty aircraft is worthy of recognition. If that is part of the timing to conclude the complete evacuation then it is not a reasonable complaint on the time to execute the evacuation.
It is a miracle that there was not a heavy loss of life in this case.
I've commented a number of times on the evacuation for a simple reason, any assumption that a fire condition is not time critical would be ill advised to develop. There is only one place to be when the aircraft is on fire, and that is outside and well away from the conflagration. Having a CFRP airframe should not give excessive comfort that additional time exists to evacuate. The reports annexes will be worthwhile reading. In this case, no one on board the A350 had any awareness that their aircraft was about to be consumed by fire, up to the moment of impact, so when the cabin crew provide the opportunity to watch to their safety presentations, read their safety cards and review your own expected exit strategy from the aircraft, it really only matters if there is a desire to live another day.
It is a miracle that there was not a heavy loss of life in this case.
I've commented a number of times on the evacuation for a simple reason, any assumption that a fire condition is not time critical would be ill advised to develop. There is only one place to be when the aircraft is on fire, and that is outside and well away from the conflagration. Having a CFRP airframe should not give excessive comfort that additional time exists to evacuate. The reports annexes will be worthwhile reading. In this case, no one on board the A350 had any awareness that their aircraft was about to be consumed by fire, up to the moment of impact, so when the cabin crew provide the opportunity to watch to their safety presentations, read their safety cards and review your own expected exit strategy from the aircraft, it really only matters if there is a desire to live another day.
Last edited by ams6110; 6th Jan 2024 at 00:16. Reason: typo
One thing that crossed my mind early on, but haven't seen it passing by...
JCG isn't part of the JMSDF, but still, it will have a similar military grading/ranking system... did a steep authority/ranking gradient come into play (in either seat direction).
The captain was slightly younger than the co-pilot. In newspapers (caution!!) the co-pilot was referred to as XO, but was this a translation of 'second-in-command' in the cockpit, or was he really the XO of the local CG base (for example)?
CVR will undoubtedly clarify this aspect.
And other aspects, which can't be confirmed by 'simple' downloading/analyzing of recorders, will CG crew-fatigue, crew-rostering, sleep patterns, etc. be made available to investigators? Or was it, 'in a crisis (=earthquake relief) an officer has to go above and beyond' ?
JCG isn't part of the JMSDF, but still, it will have a similar military grading/ranking system... did a steep authority/ranking gradient come into play (in either seat direction).
The captain was slightly younger than the co-pilot. In newspapers (caution!!) the co-pilot was referred to as XO, but was this a translation of 'second-in-command' in the cockpit, or was he really the XO of the local CG base (for example)?
CVR will undoubtedly clarify this aspect.
And other aspects, which can't be confirmed by 'simple' downloading/analyzing of recorders, will CG crew-fatigue, crew-rostering, sleep patterns, etc. be made available to investigators? Or was it, 'in a crisis (=earthquake relief) an officer has to go above and beyond' ?
Now with my analysis of the Dash-8 taxi route, I became clear to me, that
1. It was a constant motion and also through C5 until the lineup on Rwy 34R
2. The strobes had come on early on C5 (I wonder if XPDR was brought from STBY to an active mode as well)
3. From entering C5 with strobes until turning into runway, the A350 was between ~3.6NM to ~2NM away
So first question, was it possible for the A350 crew to see the Dash-8 during these 30s? Was there hindering factors like the discussed assumption of HUD's usage? This question is now a question of contributing factors.
Second question, why did the Dash-8 Crew miss to see the incoming A350, which for sure was very illuminated? They had a chance to notice it a longer period of time, including their taxi portion on C.
Let me express my opinion that the A350 crew is the least one to have missed anything important to my knowledge so far.
1. It was a constant motion and also through C5 until the lineup on Rwy 34R
2. The strobes had come on early on C5 (I wonder if XPDR was brought from STBY to an active mode as well)
3. From entering C5 with strobes until turning into runway, the A350 was between ~3.6NM to ~2NM away
So first question, was it possible for the A350 crew to see the Dash-8 during these 30s? Was there hindering factors like the discussed assumption of HUD's usage? This question is now a question of contributing factors.
Second question, why did the Dash-8 Crew miss to see the incoming A350, which for sure was very illuminated? They had a chance to notice it a longer period of time, including their taxi portion on C.
Let me express my opinion that the A350 crew is the least one to have missed anything important to my knowledge so far.
I would argue that the A350 was actually 1.0-1.5nm out.
C5 is around where the blocks are in the TDZ. On the HUD, that very point on the runway would be covered by the FPV as that's where you're aiming to fly to.
I have that very same question too. People are saying that perhaps they thought that it was going to 34L. But for an aircraft to be so close to the runway, I would have thought that it would have been easy to discern between who is landing on 34L and 34R.
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The precedent to consider in regard to the Coastguard aircraft is the 1977 Tenerife Airport disaster where KLM's most senior pilot assumed he could take off without instructions to do so. The likelihood that the pilot of the Coastguard aircraft assumed he could enter the runway without instructions is very probable. It is unlikely to be a mistake. In both cases, the individual concerned convinced themselves that they had permission to do so (KLM captain - CVR transcript; Coastguard pilot - statements after the accident). It would be interesting to know who was the real group leader on the Coastguard flight.
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Here, what they did was consistent with an understanding that 722A would jump the line as a priority departure. And TWR was in a better position to determine at which intersection to bring 722A onto 34R, because it's his runway. It does not make sense for GND to specify to TWR where 722A should enter because that's for TWR to decide.
From the FR24 playback as at 08:45 UTC (when the C5 holding position instruction was given), you can see why. 722A (no ADS-B position) was probably sitting in the space behind DL276, NH627 and 6J97 on TWY C, and ahead of NH285 and JL545. C1, C2 and C3 were blocked. C4 is a fast exit for landing aircraft and would require a >90 deg left turn and an entry putting the final approach course over the right shoulder of the aircraft -- not the ideal option. TWR was hailed by 722A, saw that C5 was the nearest and most expedient 34R access available to 722A due traffic, and directed 722A accordingly.
[Edit: Sizziano pointed out this is not a requirement.]
Last edited by Jasonbay; 7th Jan 2024 at 04:30. Reason: Corrected by Sizziano #901; add playback picture
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The information that is starting to come out is suggesting that the original times that were given for evacuation were erroneous. At 7 minutes, the person behind the LH wing station has started to move to egress, and the video that they have taken shows that there is no mass of people in front at that time. More than half of the pax are already off the aircraft by that time. The aircraft comes to rest around 30 seconds into their video, so that is at around 6:30 since coming to a halt. The assertion of 8 minutes to start and 18 minutes to conclude is less than accurate. That the PIC re-entered the aircraft after egress (if correct) and then found pax in the otherwise empty aircraft is worthy of recognition. If that is part of the timing to conclude the complete evacuation then it is not a reasonable complaint on the time to execute the evacuation.
It is a miracle that there was not a heavy loss of life in this case.
I've commented a number of times on the evacuation for a simple reason, any assumption that a fire condition is not time critical would be ill advised to develop.
It is a miracle that there was not a heavy loss of life in this case.
I've commented a number of times on the evacuation for a simple reason, any assumption that a fire condition is not time critical would be ill advised to develop.
Absolutely! Fire does not evolve in a linear fashion, and the main cause of death from fire is smoke inhalation..
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Incidentally, and now this is speculative (because aliasing effects make precise position determination beyond ~2-5m resolution measurement hard), at the distance and angle of approach that seems apparent, to move a light source over by a discernible amount -- let's say it's only 1m -- in a single frame of video... That's not a "small move". It would mean an instantaneous velocity of >100kmh.
In other words, coming from rest, we cannot really corroborate any "small move forward" from the video, or link it to any "start of the takeoff roll" either. What we see instead is that the detectable movement of 722A occurs within 1/4 second of when the first contact occurred between radome and stabiliser.
Allowing for some deformation of structures between the tail and the nose of 722A, the fact of a detectable movement of this magnitude on these timescales, even if we are unable to measure with any precision what that movement it, is much more consistent with propagation of a translation force through the length of the fuselage.
Atmospheric variables are also not really an issue. I don't see any other light sources on the airfield moving/blinking.
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Safety first, gents. Regards
.
I just hope to god it was all business on the flight deck that day on the CG aircraft.
If so a great opportunity for Japan to push just culture and human error acceptance.
If there was any non essential chit chat going on it will be basically, rightly or wrongly, pinpointed as the root cause IMO. JCAB will be moist.
If there was a cockpit gradient issue it will become a major factor.
Hopefully it doesn't become a 'deficiency of training and checking' or the floggings shall continue until performance improves. Every sim for the next 5 years will have a runway incursion. Orals will include the requirement to know the luminosity of a stop bar. Job done.
If so a great opportunity for Japan to push just culture and human error acceptance.
If there was any non essential chit chat going on it will be basically, rightly or wrongly, pinpointed as the root cause IMO. JCAB will be moist.
If there was a cockpit gradient issue it will become a major factor.
Hopefully it doesn't become a 'deficiency of training and checking' or the floggings shall continue until performance improves. Every sim for the next 5 years will have a runway incursion. Orals will include the requirement to know the luminosity of a stop bar. Job done.
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The information that is starting to come out is suggesting that the original times that were given for evacuation were erroneous. At 7 minutes, the person behind the LH wing station has started to move to egress, and the video that they have taken shows that there is no mass of people in front at that time. More than half of the pax are already off the aircraft by that time. The aircraft comes to rest around 30 seconds into their video, so that is at around 6:30 since coming to a halt. The assertion of 8 minutes to start and 18 minutes to conclude is less than accurate. That the PIC re-entered the aircraft after egress (if correct) and then found pax in the otherwise empty aircraft is worthy of recognition. If that is part of the timing to conclude the complete evacuation then it is not a reasonable complaint on the time to execute the evacuation.
It is a miracle that there was not a heavy loss of life in this case.
I've commented a number of times on the evacuation for a simple reason, any assumption that a fire condition is not time critical would be ill advised to develop. There is only one place to be when the aircraft is on fire, and that is outside and well away from the conflagration. Having a CFRP airframe should not give excessive comfort that additional time exists to evacuate. The reports annexes will be worthwhile reading. In this case, no one on board the A350 had any awareness that their aircraft was about to be consumed by fire, up to the moment of impact, so when the cabin crew provide the opportunity to watch to their safety presentations, read their safety cards and review your own expected exit strategy from the aircraft, it really only matters if there is a desire to live another day.
It is a miracle that there was not a heavy loss of life in this case.
I've commented a number of times on the evacuation for a simple reason, any assumption that a fire condition is not time critical would be ill advised to develop. There is only one place to be when the aircraft is on fire, and that is outside and well away from the conflagration. Having a CFRP airframe should not give excessive comfort that additional time exists to evacuate. The reports annexes will be worthwhile reading. In this case, no one on board the A350 had any awareness that their aircraft was about to be consumed by fire, up to the moment of impact, so when the cabin crew provide the opportunity to watch to their safety presentations, read their safety cards and review your own expected exit strategy from the aircraft, it really only matters if there is a desire to live another day.
And yes we can be very thankful that greater loss of life didnt occur.
Like Bud, my main concern was the critical comments directed at CC based purely on an arbitary figure without all the facts. If it appeared, I was suggesting that time was not critical, nothing could be further from the truth, fire/smoke is a grave emergency and probably the most time critical event someone can face on an aircraft, however crew still need to assess and make the best decisions available to them at the time. On the evidence I have seen I still think the crew did a great job, and i'm sure another few doors would have helped, but this will be analysed with all the facts. It appears that the majority were indeed out before 8mins and certainly not commencing at 8mins but watching the video it's easy to understand the gravity of the situation.
Another interesting point, emergency commands are primarily given in local language, reports today where non Japanese speakers had no idea what commands the CC were saying, so it highlights the importance of listening to the safety demo's which are usually given in in dual language.
Lastly, sorry to those that I called 'monday morning quarterbacks', I could have used better langauge, I have sat through countless hours of EP's over the years and Cabin Crew generally mention a common theme in an emergency, they start an unplanned emergency on the backfoot and often communication difficulties magnify this and the pressure on the crew in this sitaution was extreme.
We dial the wrong number, We don't catch what was meant by a statement clearly as we are distracted, we have excessive task demand and forget a step, We call Down for a gear call before it has been selected down. We confuse our own callsigns. These are errors, and everyone makes them. The system we have for air transport is supposed to recognise the potential for error, and train and design to catch errors at all opportunities. Most of the time that works, and the unintended consequence of success happens to be a lowering of the perception of risk that exists. Aviation is a relatively safe transportation system, but it is only while we, the human factors in the system, continue to understand our role in the system. [We are also our own worst enemies, when a crew does a credible job, following training and their experience, we apparently assign a status of heroic actions. That presumes that the average pilot would not have done exactly the same thing at the same time. If the report of the PIC of the A350 entering the aircraft and finding pax after exiting is correct, I for one would suggest that is a heroic action]
In this case, it appears a pretty normal evening went bad, and few of the anomalies were particularly surprising. Given the near routine state of runway transgressions in the USA of late, it is hardly reasonable to state that an SA error by the JCG crew was that exceptional that it was unable to be envisaged. What is unfortunate is that all of the other safeguards to having 2 cockpits at the same point in space and time were not functioning in a manner that could recover the SA error.
Looking out the window before lining up is only important if you want to live longer. Looking out the window before you land is also desirable. Same on take off. My personal experience on doing a GA on 24R at KLAX with the FO who was flying saying, "but... I was stable..." and then TWR asking why we went around, my response "due noise abatement..." was followed up with "the noise of hitting the plane that was parked on the runway was going to be too loud..." 28R, cleared to land, following JAL B744, who misses the only available exit and remains on the runway, so we do a GA, and again ATC asks why. "we need the practice at circuits..., and we wanted to avoid JAL.." Doing an audit, we saw the rear end of another B773ER way too close out of Pudong, from our own B7773ER, so apparently even when you line up after a landing speed bump we can forget to look out the window. (that one had me out of my seat, not a happy camper. The last time I ever gave up the center seat to another crew member. The PIC, FO, and guy in the middle seat tracked perfectly down the CL of the runway, with a B777 APU coming up fast towards them, the other aircraft having stopped on the airside of the gables. The RH observer seat is well positioned to hide everything out to the front and left of the drivers) Just because you have a clearance doesn't mean that there be no dragons.
Humans are both the strength and the weakness of our systems. The day they remove pilots from the aircraft, I'm driving and sailing everywhere, as the only thing that is more certain to fail is a computer program operating under conditions of uncertainty. AI is not an answer in the near future, if it is, then we have bigger problems to deal with.
Mandating a further pilot initiated call to TWR, with TWR read back acknowledgement, at the moment an aircraft is entering a runway, even for crossings (similar to the “entering runway” call at untowered aerodromes), would surely add an additional layer of protection against runway incursions., particularly where some time has elapsed since the prior clearance. In this instance, TWR may have picked up the runway incursion at that time. Also may have assisted in the Jan 2023 JFK DAL runway crossing incursion.
Yes, indeed!
In case the wrong impression of ADS-B capabilities might have been gathered from earlier posts, the inset in the accompanying screenshot, clearly shows that the Estimated Position Uncertainty (EPU) for the final ADSB position of the A350 (as downloaded from the ADSB Exchange website), is in the second-highest accuracy band (i.e. EPU <10m). Since the highest accuracy band for ADS-B is defined as EPU <3m... then the correct answer to Maninthebar's query about ADS-B derived position accuracy (at post #597) should effectively be: "only between 3m and 10m".
As the span of the horizontal stabiliser on a Dash 8 (at approximately 10m) is comparable to this error limit, then this also supports EXDAC's rejection of using the ADSB-derived position as reliable information to determine the lateral relative alignment at the time of collision (post #631).
I will speculate that physicus's response of: "A few centimetres" (post #601) is merely the result of confusing the available precision implied by the standard data string format (in which latitude and longitude values are each resolved to ±0.000001° - see the red-underlined figures in the accompanying image), and the actual accuracy of the position derived by the receiver from the GNSS signals.
At Tokyo's latitude, a change of 0.000001° in latitude equates to a displacement of approximately 12cm... while in longitude, (which is more relevant to lateral position on a northerly runway), the same angular change represents a displacement of just under 8cm. These geographic coordinate resolution values are therefore both equivalent to only "a few centimetres" of displacement. However, as is typical of digital systems, the ADS-B data output format appears to retain its 6-decimal-place resolution throughout, regardless of any variation in the accuracy of the GNSS-derived position which is being parsed into it. It should be noted that the error can (and often does) vary significantly, and that the FAA guidance for approving ADS-B equipment (see document link provided in EXDAC's post #631), only requires that the horizontal position error should remain below 0.05nm (or approximately 90m, i.e. wider than most runways!), for a unit to be acceptable for use within controlled airspace.
Despite the (perhaps comforting?) "digital" nature of the signal processing, it is emphasised that a position solution from any GNSS equipment is not an "exact science"... and is only an "estimation" of the true position... based on being the "best fit" to the available satellite signal data. When speed of computation is set as a priority over accuracy of result (as is generally the requirement in a moving vehicle), then the lower accuracy of the resulting position is unlikely to provide much forensic insight.
In special circumstances. GNSS technology is potentially capable of sub-millimetre relative measurement over short ranges (e.g. <100m)... albeit when assisted by differential techniques to post-process long-duration, static observation data acquired in wide open spaces (i.e. away from spurious reflected signals), using dual-frequency, survey-grade antennae (with the Phase Centres calibrated to sub-millimetre level). Unfortunately, in the real-world, the effective accuracy of most GNSS equipment in routine civilian use, will be somewhat more disappointing... possibly by 3 or 4 orders of magnitude, at times!
Not to discourage the computer-modelling community from their valuable contributions... but I well remember the rather sarcastic cry of old (from engineers looking out of the window as the reality of events diverged from the model... mostly due to a poor appreciation of the error sources): "Well the numbers are displayed on the screen and they're in colour... so they must be right! (... and remind me again, just how much we're paying for this equipment?)"
In case the wrong impression of ADS-B capabilities might have been gathered from earlier posts, the inset in the accompanying screenshot, clearly shows that the Estimated Position Uncertainty (EPU) for the final ADSB position of the A350 (as downloaded from the ADSB Exchange website), is in the second-highest accuracy band (i.e. EPU <10m). Since the highest accuracy band for ADS-B is defined as EPU <3m... then the correct answer to Maninthebar's query about ADS-B derived position accuracy (at post #597) should effectively be: "only between 3m and 10m".
As the span of the horizontal stabiliser on a Dash 8 (at approximately 10m) is comparable to this error limit, then this also supports EXDAC's rejection of using the ADSB-derived position as reliable information to determine the lateral relative alignment at the time of collision (post #631).
I will speculate that physicus's response of: "A few centimetres" (post #601) is merely the result of confusing the available precision implied by the standard data string format (in which latitude and longitude values are each resolved to ±0.000001° - see the red-underlined figures in the accompanying image), and the actual accuracy of the position derived by the receiver from the GNSS signals.
At Tokyo's latitude, a change of 0.000001° in latitude equates to a displacement of approximately 12cm... while in longitude, (which is more relevant to lateral position on a northerly runway), the same angular change represents a displacement of just under 8cm. These geographic coordinate resolution values are therefore both equivalent to only "a few centimetres" of displacement. However, as is typical of digital systems, the ADS-B data output format appears to retain its 6-decimal-place resolution throughout, regardless of any variation in the accuracy of the GNSS-derived position which is being parsed into it. It should be noted that the error can (and often does) vary significantly, and that the FAA guidance for approving ADS-B equipment (see document link provided in EXDAC's post #631), only requires that the horizontal position error should remain below 0.05nm (or approximately 90m, i.e. wider than most runways!), for a unit to be acceptable for use within controlled airspace.
Despite the (perhaps comforting?) "digital" nature of the signal processing, it is emphasised that a position solution from any GNSS equipment is not an "exact science"... and is only an "estimation" of the true position... based on being the "best fit" to the available satellite signal data. When speed of computation is set as a priority over accuracy of result (as is generally the requirement in a moving vehicle), then the lower accuracy of the resulting position is unlikely to provide much forensic insight.
In special circumstances. GNSS technology is potentially capable of sub-millimetre relative measurement over short ranges (e.g. <100m)... albeit when assisted by differential techniques to post-process long-duration, static observation data acquired in wide open spaces (i.e. away from spurious reflected signals), using dual-frequency, survey-grade antennae (with the Phase Centres calibrated to sub-millimetre level). Unfortunately, in the real-world, the effective accuracy of most GNSS equipment in routine civilian use, will be somewhat more disappointing... possibly by 3 or 4 orders of magnitude, at times!
Not to discourage the computer-modelling community from their valuable contributions... but I well remember the rather sarcastic cry of old (from engineers looking out of the window as the reality of events diverged from the model... mostly due to a poor appreciation of the error sources): "Well the numbers are displayed on the screen and they're in colour... so they must be right! (... and remind me again, just how much we're paying for this equipment?)"
The precedent to consider in regard to the Coastguard aircraft is the 1977 Tenerife Airport disaster where KLM's most senior pilot assumed he could take off without instructions to do so. The likelihood that the pilot of the Coastguard aircraft assumed he could enter the runway without instructions is very probable. It is unlikely to be a mistake. In both cases, the individual concerned convinced themselves that they had permission to do so (KLM captain - CVR transcript; Coastguard pilot - statements after the accident). It would be interesting to know who was the real group leader on the Coastguard flight.
Hanlon's razor: "Never attribute to malice that which is adequately explained by stupidity". That is also not likely to be the case, no one was being stupid on this night, they were being human. Humans err, it is our weakness and also that knowledge is often our strength. Computers also err, and give the BSOD.
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Incidentally, the movements involved are also not small, which is why it is difficult to use this footage to corroborate the captain's claim of having commenced the takeoff roll. (Anyway, who starts a night take-off roll without turning on the LDG/APP lights? The darkness would be fairly evident, even if it is not checklist/instinct to turn on the lights upon receipt of takeoff clearance.)
We are stretching the analysis into measurement of individual "pixel" distances, which I will indulge in to make a point about "small movements", even if I have refrained from doing so in the earlier analysis (which uses fixed and known references on the aircraft). If we use the horizontal distance between the two A350 anti-collision lights as a very rough gauge, the "small short movement" we are talking about is on the order of 1-2m. To advance an object 1-2m in a single frame of video, implies an instantaneous acceleration to about 100kmh. I don't think anybody can reasonably believe that the DH3 is capable of such acceleration on its own power. Even if we further discount the distance travelled 2 or 4 times, the acceleration involved is better than an F1 car's. The only object capable of exerting the impulse required is the A350.
GND's responsibility is to get departing aircraft safely across the aerodrome to or near the assigned runway. Most GND will switch you over to TWR as you approach the beginning of the runway or the queue of departing aircraft lined up.
TWR's responsibility is to manage the departure (and arrival, where applicable) flow of traffic. The runway is TWR's responsibility.
Normally, departures are handed over and cleared in FIFO sequence. However, given the nature of 722A's mission, it had priority, and it was likely understood that they would jump the line of waiting aircraft. From FR24's playback at 0845 UTC (when the C5 holding instruction was given), 722A was probably behind DL276, NH627, 6J97 which were occupying TWY C and blocking intersections C1, C2, and C3. C4 might have been accessible but it is a fast exit meant for aircraft landing on 16L, and would have required a >90 degree left turn anyway, putting arriving traffic over the right shoulder of the aircraft/crew -- not the best option. Figuring out where 722A could slot in and access the runway would have been dynamic depending on where the other aircraft were. Therefore, it is something TWR is in a much better position to do than GND.
Put another way, at an airport that has multiple parallel run-up spots just short of the runway entrance, it is not GND but TWR that tells departures their sequence and who gets to move up to the runway first. You can think of the southern portion of TWY C as a large run-up area, and TWR is plucking aircraft (usually from the head of the line) to clear onto the runway for departure.
This explains why GND simply instructed 722A to taxi down C and then instructed the frequency change.
It is certainly a contributory factor, albeit minor, however, that C5 was chosen, given its distance away from the runway threshold. It may conceivably have played a part in preventing/delaying recognition of the DH3 by the JAL pilots, since by short final they would have been focused on the threshold, followed by the TDZ -- i.e. where they want to land -- and could easily have missed an aircraft among the lights at the far end of the TDZ. Even if they saw DH3 prior to touchdown, the difference between spotting an obstacle at the threshold and at the end of the TDZ is not a matter of time, but also of altitude. At the lower altitude, and near idle power, there really isn't much that can be done to avoid a collision.