Paul Holmes and Erebus
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Sorry - I should have been more accurate. I meant "pre-computerised flight plan". Prior to this computerisation which took place in 1978, the flight plans were manually entered, waypoints printed from a computer and weather/fuel details manually added. Change of waypoints, such as the move from Williams Field to the McMurdo NDB which happened in 1977 would therefore have been relatively easy to pick up on. At the time of computerisation, Chief Navigator Hewitt's first error was to enter the Williams Field co-ordinates rather than those of the NDB. His second error was to mis-key those co-ordinates, which had the effect of subsitituting a 4 for a 6 and situating the waypoint 25 miles away over the Dailey Islands.
That may have been the idea in 1977 and early 1978, but in practice this is not what happened after then. If the pilots handed the post-computerisation flight plan at the briefing followed that track, then they'd know it never went anywhere near the NDB, and I firmly believe that they either thought the NDB required them to go off-track in bad conditions, if indeed this procedure was described and trained as you say (I've certainly never read anything about Collins and Simpson flying the NDB on a simulator post-briefing), or that the NDB was simply a holdover from before the computerised flight plans.
What I get a sense of when revisiting this stuff is a kind of organisational entropy that I didn't really experience first-hand until I went into industry myself. New projects start with the best intentions and everyone sticks to the script initially, but as things become more commonplace mistakes start to slip in, changes are made but not communicated between different departments and what started as a co-ordinated and coherent execution plan slowly falls apart. You've got two changes of waypoint - one intentional, the other not - within two years. You've got some briefing materials that are relevant to the flight concerned as well as some that are out of date. You have a briefing itself that is gradually - in your own words - becoming less and less relevant to the actual conduct of the flight being briefed. As a result, you have crews mostly believing that the INS track they are following does not reference the NDB at all and instead goes down McMurdo Sound.
I believe that Collins and his crew thought the same. If, as you suggest, he left the briefing thinking that the NDB might play a part in his flight and that the NDB was the waypoint, then why did he not flag the discrepancy after he had plotted the waypoints the previous night (logically the most trustworthy document he was given) and found a track that went well west of the NDB? The track from Hallett to the NDB does not involve McMurdo Sound by the way, but skims the eastern edge of the Sound, passing direct over Cape Bird and the western slopes of Erebus. If that was the nav track he thought he was following, then 1,500ft was too low for an approach from the north and there's no way he'd have re-engaged NAV mode at that altitude.
There's just too much discrepancy between what Capt. Wilson claimed he was saying at the briefings regarding the track and the NDB, and what a majority of pilots left the briefing thinking that they had been told - enough to suggest that Wilson didn't make McMurdo *Station* clear in his description of the track, or if he did then he certainly did not communicate his intent effectively.
I note in an earlier thread that you considered yourself "anti-Mahon", and I've been racking my brains trying to think why that could be. I know there's a resistance from some in the piloting fraternity to allowing non-pilots to make judgements on the operation of flights, but that attitude seems a little "knee-jerk" from someone who has thought about it to the extent you clearly have. I could understand it if he had simply taken the submissions of NZALPA and the dead crew's family counsel as read before writing his report and dismissing out of hand the ANZ/NZCA submissions due to their evasive and occasionally truculent behaviour at the inquiry - but he did not. He went to extraordinary lengths to put himself in the mindset of a line pilot facing a situation like that faced by the ill-fated crew in terms of technical understanding, and the "grey areas" that crop up when the black-and-white diktats of regulations are contradicted by the realities on the ground, and indeed in the sky. What he found was that the crew was given at best conflicting - if not misleading - information to start with due to the organisational entropy I referred to earlier regarding the briefing, that a protocol-breaching unannounced co-ordinate change altered the flight path from the one the crew were expecting to that of a collision course with a mountain, that the crew were dispatched without proper training on the whiteout conditions which they could experience and that given this state of affairs the crew did everything they reasonably could with the information they were given to conduct the flight safely. This is before we get on to the more controversial actions of ANZ in the wake of the accident.
In that situation, the idea was to stay on the track until past the summit and then do an out-and-back cloud-break using the NDB.
What I get a sense of when revisiting this stuff is a kind of organisational entropy that I didn't really experience first-hand until I went into industry myself. New projects start with the best intentions and everyone sticks to the script initially, but as things become more commonplace mistakes start to slip in, changes are made but not communicated between different departments and what started as a co-ordinated and coherent execution plan slowly falls apart. You've got two changes of waypoint - one intentional, the other not - within two years. You've got some briefing materials that are relevant to the flight concerned as well as some that are out of date. You have a briefing itself that is gradually - in your own words - becoming less and less relevant to the actual conduct of the flight being briefed. As a result, you have crews mostly believing that the INS track they are following does not reference the NDB at all and instead goes down McMurdo Sound.
I believe that Collins and his crew thought the same. If, as you suggest, he left the briefing thinking that the NDB might play a part in his flight and that the NDB was the waypoint, then why did he not flag the discrepancy after he had plotted the waypoints the previous night (logically the most trustworthy document he was given) and found a track that went well west of the NDB? The track from Hallett to the NDB does not involve McMurdo Sound by the way, but skims the eastern edge of the Sound, passing direct over Cape Bird and the western slopes of Erebus. If that was the nav track he thought he was following, then 1,500ft was too low for an approach from the north and there's no way he'd have re-engaged NAV mode at that altitude.
There's just too much discrepancy between what Capt. Wilson claimed he was saying at the briefings regarding the track and the NDB, and what a majority of pilots left the briefing thinking that they had been told - enough to suggest that Wilson didn't make McMurdo *Station* clear in his description of the track, or if he did then he certainly did not communicate his intent effectively.
I note in an earlier thread that you considered yourself "anti-Mahon", and I've been racking my brains trying to think why that could be. I know there's a resistance from some in the piloting fraternity to allowing non-pilots to make judgements on the operation of flights, but that attitude seems a little "knee-jerk" from someone who has thought about it to the extent you clearly have. I could understand it if he had simply taken the submissions of NZALPA and the dead crew's family counsel as read before writing his report and dismissing out of hand the ANZ/NZCA submissions due to their evasive and occasionally truculent behaviour at the inquiry - but he did not. He went to extraordinary lengths to put himself in the mindset of a line pilot facing a situation like that faced by the ill-fated crew in terms of technical understanding, and the "grey areas" that crop up when the black-and-white diktats of regulations are contradicted by the realities on the ground, and indeed in the sky. What he found was that the crew was given at best conflicting - if not misleading - information to start with due to the organisational entropy I referred to earlier regarding the briefing, that a protocol-breaching unannounced co-ordinate change altered the flight path from the one the crew were expecting to that of a collision course with a mountain, that the crew were dispatched without proper training on the whiteout conditions which they could experience and that given this state of affairs the crew did everything they reasonably could with the information they were given to conduct the flight safely. This is before we get on to the more controversial actions of ANZ in the wake of the accident.
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Gawd, hasn't this topic been done-to-death by now, some 30+ years down the track??? Many contributors to this and other threads on Erebus are well known for their contentious and entrenched views... there's nothing new to add!!!
As for Paul Holmes, starve the idiot of oxygen, he'll go away.
As for Paul Holmes, starve the idiot of oxygen, he'll go away.
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DozyWannabe, a well written post that was a pleasure to read - and containing a few hints that we are getting near the end of your contributions! (for the moment).
I sense this thread is getting near its end, but I'm sure there will be more threads on this accident in the future. I would like to thank DozyWannabe, prospector, Ampan, framer and all the others for a civilised and thoughtful discussion. For students of air safety, such as myself, these discussions are invaluable.
Hopefully, all of you will still be with us when this topic comes up again in 2019!
Dozy, you touched on a point that I was about to bring up. You described it - very articulately - as "organisational entropy", and described how this effect would have made for a briefing that was far less useful than could have been.
I was about to direct a post at Ampan about the "quality" of that briefing.
Ampan, I believe your views re the effectiveness of that briefing are seriously misplaced.
From what I have read, that briefing was full of little inaccuracies and contradictions.
We have all attended briefings like that. At first, you are tempted to ask questions to resolve the confusions, but after a short while, you realise there is almost no value in questioning. Instead, you just sit back and take *everything* with a pinch of salt.
Could this have been the reason Collins felt compelled to plot the route for himself?
Everybody says he did it because he was "meticulous". If it had been me, I would have been plotting it purely because the briefing was a dogs breakfast - but probably would not have if I felt the briefing was respectable.
I have been saying for a week now that there was nothing the pilots could reasonably have been expected to do differently.
The same could not be said for Air New Zealand or the CAA.
I sense this thread is getting near its end, but I'm sure there will be more threads on this accident in the future. I would like to thank DozyWannabe, prospector, Ampan, framer and all the others for a civilised and thoughtful discussion. For students of air safety, such as myself, these discussions are invaluable.
Hopefully, all of you will still be with us when this topic comes up again in 2019!
Dozy, you touched on a point that I was about to bring up. You described it - very articulately - as "organisational entropy", and described how this effect would have made for a briefing that was far less useful than could have been.
I was about to direct a post at Ampan about the "quality" of that briefing.
Ampan, I believe your views re the effectiveness of that briefing are seriously misplaced.
From what I have read, that briefing was full of little inaccuracies and contradictions.
We have all attended briefings like that. At first, you are tempted to ask questions to resolve the confusions, but after a short while, you realise there is almost no value in questioning. Instead, you just sit back and take *everything* with a pinch of salt.
Could this have been the reason Collins felt compelled to plot the route for himself?
Everybody says he did it because he was "meticulous". If it had been me, I would have been plotting it purely because the briefing was a dogs breakfast - but probably would not have if I felt the briefing was respectable.
I have been saying for a week now that there was nothing the pilots could reasonably have been expected to do differently.
The same could not be said for Air New Zealand or the CAA.
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Prospector,
I shouldn't have to spell it out to such a knowledgeable chap as you, surely, should I?. See #103
Now, I suspect that you meant to say that you dial in a VOR frequency to get a paired TACAN in a VORTAC arrangement, but that's not what you actually said.
If you want to present as an expert, please give correct information! And please don't lower yourself to learned lectures, particularly about VHF DME. Do you recall where DME was invented?
I shouldn't have to spell it out to such a knowledgeable chap as you, surely, should I?. See #103
The DME is paired with the TACAN and uses VHF frequencies,
If you want to present as an expert, please give correct information! And please don't lower yourself to learned lectures, particularly about VHF DME. Do you recall where DME was invented?
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FGD,
Thank you for the summary.
Do you have any general thoughts why, after so many years, the two "sides" can't seem to agree?
One sticking point for me: is that AINS really to be trusted to the same degree as either A) one's eyes; B) ground based instruments? Neither of these alone could be relied on at the time the let-down commenced. I find the argument they had justification in treating AINS as a substitute for an instrument let-down (effectively the case) contradicted by precisely the type of confusion that led to the accident. Isn't that enough to declare reliance on AINS dangerous in any analogous situation? What would you suppose most commercial pilots would say?
Finally, isn't there something intuitive that before descending below clouds, and in VMC, that you positively identify the location of the mountain first? Isn't that just basic, even while acknowledging the validity of the many cruel coincidences working against the crew?
I, for one, will be here again in 2019 as long as the answers to these basic questions are not explained to my full satisfaction.
Thank you for the summary.
Do you have any general thoughts why, after so many years, the two "sides" can't seem to agree?
One sticking point for me: is that AINS really to be trusted to the same degree as either A) one's eyes; B) ground based instruments? Neither of these alone could be relied on at the time the let-down commenced. I find the argument they had justification in treating AINS as a substitute for an instrument let-down (effectively the case) contradicted by precisely the type of confusion that led to the accident. Isn't that enough to declare reliance on AINS dangerous in any analogous situation? What would you suppose most commercial pilots would say?
Finally, isn't there something intuitive that before descending below clouds, and in VMC, that you positively identify the location of the mountain first? Isn't that just basic, even while acknowledging the validity of the many cruel coincidences working against the crew?
I, for one, will be here again in 2019 as long as the answers to these basic questions are not explained to my full satisfaction.
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The two sides can't agree because one says the crew was blameless.
Captain Collins would say that he was using his eyes (Visual Meteorological Conditions), with the AINS to assist, rather than the other way around. Putting the rules to one side, and assuming it was night, could you use the AINS to fly a DC10 down McMurdo Sound below MSA? It was about 40 miles wide, so maybe you could (although the last update was at Christchurch). But if you were going to do that, the location of the waypoint at the end of the Sound would be a matter of critical importance, because that is the only thing that will keep the aircraft between the high ground on either side. This is why I don't buy FGD135's argument re the briefing. Of course it was a bad briefing, but there would have been plenty of those. The captain would have left the briefing thinking that the track would be down the Sound to Mac Station. When, the night before the flight, the captain plotted the track using an old flightplan he got at the briefing, there would have been an issue raised in his mind re the final waypoint, which was not at Mac Station. He obviously assumed that the flightplan he would be given the next morning would be the same as the one he plotted, but he had to check that one particular waypoint - or else stay above 16000 feet.
Captain Collins would say that he was using his eyes (Visual Meteorological Conditions), with the AINS to assist, rather than the other way around. Putting the rules to one side, and assuming it was night, could you use the AINS to fly a DC10 down McMurdo Sound below MSA? It was about 40 miles wide, so maybe you could (although the last update was at Christchurch). But if you were going to do that, the location of the waypoint at the end of the Sound would be a matter of critical importance, because that is the only thing that will keep the aircraft between the high ground on either side. This is why I don't buy FGD135's argument re the briefing. Of course it was a bad briefing, but there would have been plenty of those. The captain would have left the briefing thinking that the track would be down the Sound to Mac Station. When, the night before the flight, the captain plotted the track using an old flightplan he got at the briefing, there would have been an issue raised in his mind re the final waypoint, which was not at Mac Station. He obviously assumed that the flightplan he would be given the next morning would be the same as the one he plotted, but he had to check that one particular waypoint - or else stay above 16000 feet.
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I never once needed an AINS, VOR or anything else to fly tours in the Grand Canyon on the way to the South rim, that's because it was a VMC mission, if I couldn't see the canyon, I didn't do the tour.
Do you have any general thoughts why, after so many years, the two "sides" can't seem to agree?
The two sides can't agree because one says the crew was blameless.
-I think most people would agree that a cultural precedent had been set of going below 6000ft.
-I think most would agree there was ambiguity regarding the flight path.
-Everyone agrees that Air NZ behaved badly after the event.
Where we can't agree is whether or not the crew could have/should have performed the flight differently and thus avoided the crash.
I sense this thread is getting near its end, but I'm sure there will be more threads on this accident in the future. I would like to thank DozyWannabe, prospector, Ampan, framer and all the others for a civilised and thoughtful discussion. For students of air safety, such as myself, these discussions are invaluable.
As I've looked more and more into this over the years, for me, one lesson keeps appearing as obvious. I would be interested in hearing the No. 1 lesson you folk have dragged from Erebus.
Mine is Minimum Safe Altitudes are your last safety net that will protect you from mistakes and errors that yourself and others make.Respect it.
When I say Minimum Safe Altitudes I am not just talking about those on a chart, I am also talking about recommended heights. Anytime someone sees fit to suggest a minimum safe height, it is to keep you from hitting the ground. There are other accidents since Erebus where these heights were not respected, and like Erebus, they ended in disaster because of errors ground personnel had made.
See you in 2019, Framer....... out.
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[EDIT - A more visual description of the three tracks (TACAN, NDB, Dailey Islands) can be seen here : ]
At least Wilson was honest about verbally overriding the MSAs at the inquiry - though I don't think Morrie Davis would have thanked him for it.*
At the end of the day there are always going to be differences of opinion, especially where pilots are concerned - because generally being conscientious, professional types - the tendency is to hope that they would pick up on the kind of insidious lowering of safety margins that occurred in this case and would find the right combination of actions to get around it - unfortunately history shows that's not always the case.
Framer makes a good point about MSAs, but in this case they had been specifically briefed that the MSAs didn't apply if a certain set of conditions were met, and in this case - even though the weather wasn't the best it had been in the past - those conditions were met. One could argue that the memo regarding the NDB withdrawal should have immediately caused that verbal dispensation to be struck from the briefing, but it was not.
My opinion that the flight crew should not hold any blame for what happened is formed not because I exclusively agree with Mahon or Vette over everything, nor do I think that Chippindale's technical investigative work was particularly flawed (other than the CVR/FDR transcription methodology - but to be fair he'd never done it before and should be given the benefit of the doubt) - it's simply based on the idea of how much could reasonably be expected of line pilots in an organisation which had such severe communications problems bubbling under the surface. As far as they were aware, the nav section had prepared a flight plan which, while not strictly adhering to the briefing materials, had nevertheless worked flawlessly for 14 months. Collins (and possibly Cassin too) had gone a step further and manually cross-checked and re-checked that flight plan, stuck to what they were told in the briefing in terms of MSA and trusted that it would keep them out of trouble. Did they do everything they were physically or mentally capable of? Possibly not. Did they do everything that could reasonably be expected of them? I think so.
[* -There's an interview with Vette where he describes being summoned to Davis's office following his testimony - he asked if Davis had brought his sword because he presumed he was goingto cut his stripes off, Davis's response being "I'm going to cut your f*****g b******s off!".]
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Gidday Chris!
Several times you have asked the following question. Apologies that I have not answered it sooner.
and
There was nothing unsafe about how they used the AINS. They used it exactly the same way as I or anybody else would have. In fact, it could be said that to have NOT used it that way would have been poor piloting (in the sense that the humans on the flight deck would have then had to work a little harder).
INS was not then, and has never been, considered a navigational aid upon whose sole use the aircraft may be navigated below the MSA/LSALT. It has only ever been approved for enroute navigation (where the aircraft is safely above minimum altitudes).
It may appear that they were using it for sole means navigation below the minimum altitudes in this case, but in reality it was the pilots that had assumed navigation responsibility visually. In other words, the pilots were navigating the aircraft - not the INS. The INS was just "helping out", so as to speak.
This is a like your car GPS telling you were to turn. You are the one who is taking responsibility for where the car is actually going. If you don't like where the GPS wants to take you, you choose something different. The GPS is just helping out and is not responsible for where the car goes.
Several times you have asked the following question. Apologies that I have not answered it sooner.
... is that AINS really to be trusted to the same degree as either ...
... why using AINS in the manner the crew of 901 did was unsafe?
INS was not then, and has never been, considered a navigational aid upon whose sole use the aircraft may be navigated below the MSA/LSALT. It has only ever been approved for enroute navigation (where the aircraft is safely above minimum altitudes).
It may appear that they were using it for sole means navigation below the minimum altitudes in this case, but in reality it was the pilots that had assumed navigation responsibility visually. In other words, the pilots were navigating the aircraft - not the INS. The INS was just "helping out", so as to speak.
This is a like your car GPS telling you were to turn. You are the one who is taking responsibility for where the car is actually going. If you don't like where the GPS wants to take you, you choose something different. The GPS is just helping out and is not responsible for where the car goes.
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However that answer is inadequate, not to mention facetious. Aside from the co-ordinates programmed, I don't think there was actually anything "unsafe" about the crew's use of AINS. The mitigating factors are:
- That they didn't know they were programming a course over Erebus
- That the ground aids in the area were spartan to start with, and became even more so
- That we don't know exactly what the radar situation was in the four minutes or so immediately prior to impact
We've covered these points several times over in the last week or two, so I'm not going to revisit them here.
The deal with AINS is that while it looks like stone-age technology by modern standards, it was completely state-of-the-art at the time and was orders of magnitude more accurate than any previous auto-navigation tool. At worst, it clocked about 2 miles of deviation at the point they were at - in an area notoriously difficult to navigate, but there's nothing to say it was even off by that much (as proven by the impact point and wreckage being almost bang-on the programmed track). The reason it took so long to find initially was because the searches were being carried out on the expected Dailey Islands track - in itself because Mac Central never received the updated co-ordinates, although early press reports stated (incorrectly) that the aircraft was found significantly off-track in the rush to get the morning headlines (and thus the first myth about the crash gained traction).
The crew would have checked and cross-checked the data as they entered it at the gate, there was no mis-keying on their part, and on the system's part it followed the entered nav track extremely faithfully.
Now, if you were to ask how the *company* used AINS in an unsafe manner, my answer would be different. Even if we take Hewitt's late-night and unannounced correction to be an aberration, the switch to computerised flight plans required more care to be taken when communicating additions or changes to the flight plans to the rest of the company. This is one of the earliest occasions where the danger of increased automation breeding complacency reared it's head (and whatever else you may think about them, without Vette and Mahon it would not have been understood as early as it was without them). With a manual calculation step before leaving ops, an implicit redundant check was created as a side-effect.
If a change was made and the waypoints handed over before notification reached ops, then the manual calculations would serve as an extra level of redundancy - i.e. if the maths didn't make sense compared to the crew's expectations, then this would have to be investigated. By computerising the flight plans completely, those calculations became opaque to the crew, and so the only way to notice a discrepancy would be to manually compare the briefing co-ordinates they were given with those on the flight plan - which I understand was not normal practice at the time.
By computerising the flight plans, and with the knowledge that the AINS was a technological marvel which rarely got things wrong, it became possible for a mistake or change made by nav section to make it all the way into the aircraft's computers without the knowledge of the crew - as demonstrated by the supposedly "false" Dailey Islands track being flown for 14 months with no-one picking up on it. To be fair to ANZ, the need for absolute adherence to communication protocols between different departments when a process is automated was not well-understood at the time - but on the other hand, given their willingness to point the finger at the crew for breaking a protocol that they were in fact instructed they could break at the briefing, Hewitt's non-communication of the flight plan change to either ops or the crew hoists ANZ by their own petard.
Secondary to this was the practice regarding Antarctic flights whereby the next two crews to make the journey were briefed together. This led to a situation where a period of 3 to 4 weeks would elapse between the second crew being briefed on the flight and the flight itself. With the manual system this was fine, as I described above - but with the computerised flight plans communication between nav section and ops becomes a single point of failure, which anyone involved in systems analysis and design will tell you is a Very Bad Thing. Mitigating this, again, is the fact that systems analysis as a science was in it's infancy in the late '70s and these problems were not common knowledge - but to my mind a company that was as proud of it's safety record as ANZ was should have known better.
[EDIT : In addition to the excellent post above from FGD135, I'd like to add that the switch from INS navigation to visual navigation began at the start of the let-down, with the intent that visual be the primary navigation method, with INS and radar as a back-stop. What you hear in the last couple of minutes of the CVR is the crew confirming (i.e. re-checking) their position visually, in the belief that the INS will keep the aircraft pegged in the middle of McMurdo Sound should they lose visual contact with their fixes. As the level of whiteout increases, they make a sensible decision to err on the side of caution and climb - not because they are unsure of their position but because the whiteout has made it impossible to confirm if they were to proceed any further. Unfortunately by then it is too late. ]
Last edited by DozyWannabe; 11th Dec 2011 at 05:17.
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Originally Posted by FGD135
It may appear that they were using it for sole means navigation below the minimum altitudes in this case, but in reality it was the pilots that had assumed navigation responsibility visually.
(PS I know I've been re-iterating these questions in various wordings repeatedly, but I'm doing this because I still don't feel I have the argument down definitively just yet.)
I'd like to know the lessons you guys think are most important from Erebus so I can consider them.
Short and sharp, one sentence type answers is what I'm after if thats possible, cheers folks.
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Thanks again Dozy for your detailed thoughts. Yes, we have gone over this before. But. . . .
Let's forget Erebus for a moment and speak in general terms. Could we agree that because AINS (in 1979) relies on humans typing in numbers into a program, and requires coordinates to be re-entered continuosly to match the route being flown, that this introduces a specific "error mode" that presumably does not apply to a stationary ground instrument?
Originally Posted by DozyWannabe
That they didn't know they were programming a course over Erebus
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What makes you say that? The let-down was performed in the patchy cloud north of Ross Island, where it was possible to make out visual landmarks. The overcast affected only Ross Island itself. Regarding your post #196 - the manual keying in of the data was covered by a redundancy check. One pilot read the values, the other keyed them in and read them back for cross-check purposes. This was enough to ensure that mis-keying at the gate should not be a problem. AFAIK the only accident relating to mis-keying a nav computer (AA965) was in part caused because this protocol was not followed.
@framer - The myriad circumstances and lessons to learn surrounding this landmark accident in aviation unfortunately don't lend themselves to quick or easy summary. The best I can do is:
"Any safety-critical system is inevitably more complicated than the human brain will initially think it is - always assume that your best may not be good enough and make sure every contingency is covered".
@framer - The myriad circumstances and lessons to learn surrounding this landmark accident in aviation unfortunately don't lend themselves to quick or easy summary. The best I can do is:
"Any safety-critical system is inevitably more complicated than the human brain will initially think it is - always assume that your best may not be good enough and make sure every contingency is covered".
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What makes you say that? The let-down was performed in the patchy cloud north of Ross Island, where it was possible to make out visual landmarks
That means to me that they needed certainty of position before they started down. But clearly they did not have this certainty yet
And there you have it, the landmarks were interpreted wrongly, and there was no certainty, the crew made these mistakes, therefor how can they be held blameless??
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Because it was proven scientifically that any crew in the same situation would probably have mistaken one for the other due to the visual illusions in that location in those conditions at that time - it was rotten luck, not something they should be blamed for. Changing the co-ordinates, overruling the MSA, letting the briefing deteriorate, not communicating effectively - these were all things ANZ could and should have done something about.
No matter how you try to argue it, this isn't the same as a military flight or a Piper Cub, because in a professional line operation this crew had a right to expect that their colleagues would do right by them - instead they let them down, and continued to do so even after they were dead.
No matter how you try to argue it, this isn't the same as a military flight or a Piper Cub, because in a professional line operation this crew had a right to expect that their colleagues would do right by them - instead they let them down, and continued to do so even after they were dead.
Last edited by DozyWannabe; 11th Dec 2011 at 16:16.
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"We're 26 miles north. We'll have to climb out of here."
If you're 26 miles north on a track to a waypoint 20nm west of Mac Station, you don't have to climb out of anything.
If you're 26 miles north on a track to Mac Station, then you have Erebus dead ahead and definitely do have to climb out.
If you're 26 miles north on a track to Mac Station, then you have Erebus dead ahead and definitely do have to climb out.
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The radar situation is perfectly obvious, there is no way the flight was showing on radar, there is no terrain piercing radar yet invented.
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That we don't know exactly what the radar situation was in the four minutes or so immediately prior to impact