Erebus 25 years on

[Graybeard]

700 Feet Statement in Error

OK, guys, I apologize for writing that the plane was ever at 700 feet. I was working from memory, and never had access to the accident report. I don't believe I ever wrote or implied that they hit at anything below 1465 feet, however.

"No change in altitude is recorded as a result of this pitch up although the NSU memory module recorded a plus 10 fps acceleration at impact."

What is an NSU, Brian?

GB

[Desert Dingo]

Graybeard:
Thanks for making that correction. I appreciate your honesty.

Just shows how careful we should all be when making any claim of anything to be a fact in this discussion. (It is not good enough to use the appeal to authority - like "Sir Someone Hyphened-Name and others said.... " that is so prevalent here. I will only be convinced that a correct conclusion has been reached if I can verify that the source data used for the premise is accurate).

Your NSU query;
Looks like Brian had a bit of fat finger trouble there.
The original Chippindale reference (Annex D p6) is to the NCU.
This is defined in the report at 1.18.1 as a Navigation Computer Unit.
Chippindale writes about "new investigation techniques" where the manufacturer was able to extract data not normally available.
Seems to be exactly what you were referring to in your post, although no actual retrieved speeds or altitudes are mentioned.

[ampan]

back to my hobby-horse

What did Mahon actually say about Capt. Wilson's evidence? It's at pp55,60 of the Mahon Report:

"The evidence given by Captain Wilson and Captain Johnson as to the verbal content of the RCU briefing was not accepted by the majority of pilots who attended the briefing. Indeed, there was one pilot who said that upon listening to the evidence given before the Commission in relation to the briefing which he attended, he was led to wonder whether he had been at the same briefing."

Mahon’s first sentence, insofar as it refers to the evidence of Capt. Wilson, is not accurate. Capt. Wilson said “… it was made plain that the track was a direct track from Cape Hallett to McMurdo.” (MacFarlane p212). None of the three surviving pilots disputed that evidence. Capt. Wilson went to say that he indicated that the nav track was over Erebus (p213). This is the evidence that was disputed

As regards Mahon’s second sentence, who was this pilot, and what did he actually say? The following extract is from the cross-examination of Capt S. (MacFarlane p687):

And you would accept no doubt there are areas where your recollection diverges from that of Captains Johnson and Wilson?

Yes.

Would you accept that they and your’s could be at fault in certain areas of personal recollection?

I make no claim to having an impeccable memory. I heard and saw the briefing once so I have had no other experience of a briefing to confuse my general recollection. There may be some fine points that are a little beyond my personal recollection. But I think, in fairness to Captains Johnson and Wilson, as they have stated in their evidence they have been called upon to demonstrate their aspect of the briefing several times. And it is my opinion only that possibly unconsciously each time they demonstrated they inadvertently improved it somewhat. Captain Wilson’s evidence in general I have no great conflict with. It’s just the extreme fine detail that he appears to have included for the commission that I don’t recall. In Captain Johnson’s case however, the description I heard in this court was so different to my recollection, that I wondered if in fact I had attended the same briefing.

It is obvious that Capt. S. was not referring to Capt. Wilson’s evidence about the briefing. So Mahon’s second sentence, insofar as it refers to the evidence of Capt. Wilson, is, again, not accurate.

The quoted passage from Mahon’s report suggests that he lumped Captains Johnson and Wilson together and treated them as one witness – and that he made a mistake as a result. But if you read on a little further (Mahon Reprt, p60, para 164), Mahon sums up his findings about the briefing, and says this:

“The pictorial representations showed the observers that the flight path was down McMurdo Sound and these displays would, not unnaturally, take precedence over the spoken words indicating a direct track from Cape Hallett to McMurdo Station and indicating the NDB co-ordinates as the destination waypoint.”

So the judge did not make the mistake of lumping Captains Johnson and Wilson together. It appears that he recognised that no-one disputed Capt. Wilson’s evidence that he told the crew that the nav track went to the NDB at McMurdo Station.

Where does this leave us? It leaves us with the Mahon Report containing a clear finding that Captain Collins and F/O Cassin were told at the briefing that the nav track went to the NDB at McMurdo Station. It leaves us with Capt. Collins, 18 days later, plotting the nav track and discovering that it did not go to the NDB at McMurdo Station. The issue then is this: Would the average commercial pilot, exercising a reasonable degree of care and attention, have been alerted to a potential issue concerning the final waypoint? In my opinion, the answer to that question is a definite ‘yes’. Therefore, the failure to check the waypoint was an error.

So the captain and the F/O were not insane, or suicidal. They were simply careless. They should have checked, and they didn’t. 999 times out of a 1000, their error would have been of no consequence. In this particular case, however, as result of significantly greater carelessness by other employees of AirNZ, a disaster occurred. But the fact that the crew were killed and that most of the fault lay with AirNZ does not give the crew some sort of immunity from criticism. They were paid, and very well paid, to do a job, and part of that job was to be alert to the very type of situation that led to this accident.

25%.

[Brian Abraham]

Yes, sorry Greybeard, as DD says should be NCU, in my haste (lesson there) wrote NSU in my long hand notes.

[prospector]

"No, just interested in why it was OK for some flights to tool about at 1,000 feet AGL."

If indeed there were flights that "tooled around at 1,000ft AGL", they were all in crystal clear CAVOK conditions, after they had been identified and position confirmed by McMurdo radar.

[Brian Abraham]

Folks, I find the attempts to apportion “blame” a fruitless exercise. We all adjudge different nuances as having greater importance than others in leading to the accident. Who is to say which of those nuances has a greater role to play. The crew are not available to explain why they thought any particular action they made on the day seemed like a good idea at the time. The crew were professional aviators in every sense of the word, and as I’ve said previously it was only a matter of time before an incident/accident occurred. To that end, I’d like to put a scenario to you and see who you would adjudge as having erred.

The DC-10 is tracking inbound to McMurdo from Hallett and has descended to the LSALT of FL160 in preparation for a VMC descent to 6,000 feet in accordance with company procedures when overhead McMurdo. On passing overhead Mount Erebus the aircraft is impacted by a lava bomb thrown up by the vulcano. The aircraft is rendered uncontrollable and impacts the southern slopes of Mount Erebus in a vertical dive. This is a non-survivable accident.

Some will say it’s the pilots fault and point to various regulations to back their claims, such as Australian CAR regulation

224 Pilot in command
(1) For each flight the operator shall designate one pilot to act as pilot in command.
Penalty: 5 penalty units.
(1A) An offence against subregulation (1) is an offence of strict liability.
Note For strict liability, see section 6.1 of the Criminal Code.
(2) A pilot in command of an aircraft is responsible for:
(a) the start, continuation, diversion and end of a flight by the aircraft; and
(b) the operation and safety of the aircraft during flight time; and
(c) the safety of persons and cargo carried on the aircraft; and

239 Planning of flight by pilot in command
(1) Before beginning a flight, the pilot in command shall study all available information appropriate to the intended operation, and, in the cases of flights away from the vicinity of an aerodrome and all I.F.R. flights, shall make a careful study of:
(a) current weather reports and forecasts for the route to be followed and at aerodromes to be used;
(b) the airways facilities available on the route to be followed and the condition of those facilities;
(c) the condition of aerodromes to be used and their suitability for the aircraft to be used; and
(d) the air traffic control rules and procedures appertaining to the particular flight; and the pilot shall plan the flight in relation to the information obtained.

Would it have been the pilots “fault”? Or rather a systems failure?

[ampan]

Lava bomb analogy

The lava bomb is much the same as a sector whiteout, isn't it? If the crew has no reason to be alerted to the risk of a lava bomb, then it's definitely a systems failure, ie, crew has 0% of the blame. (The word "blame" is not a particularly pleasant one, but it's a word that cannot be avoided, in my opinion.)

But what if the crew, 19 days earlier, had been told of the possible risk of a lava bomb? And what if they disregarded what they had been told? In that situation, why shouldn't the crew get a share of the blame?

[prospector]

Brian Abraham,
" Folks, I find the attempts to apportion “blame” a fruitless exercise."

That is why the official accident report compiled by the Chief Accident Inspector states "Probable Cause".

It is only Mahon who states, in his opinion, who was to blame.

[ampan]

The Blame Game

Correct, Prospector. Mahon started it.

[Brian Abraham]

I'm sorry. To me Chippendale's probable cause lays all the "blame" at the feet of the Captain, and that is what caused the dissension (Mahon etc). In his conclusions he covers the ground extremely well as to the systemic failures and I would give him 9.5 out of 10 for his report. In fact, given the comments he makes in his conclusions it is somewhat difficult, I find, to reconcile his probable cause. Perhaps it's just me. All the brouhaha would have been avoided with the modern day method of reporting in which the conclusions chapter lists the latent failures, along with the active failures, and ends with safety recommendations. Nobody is placed in the position of being "blamed" (negligence aside) because the question asked with regard to latent and active failures is always "why", and the necessary recommendations are made to put measures in place to avoid a repeat. The Qantas Bangkok over run report is absolutely outstanding in how the investigators address the latent and active failures, highly recommended reading.

they were all in crystal clear CAVOK conditions

prospector, it would seem you have little understanding or appreciation of the hazards revolving around operations in the polar regions, else you would not be making that statement. You're not to be faulted for that of course. And it's the reason I keep saying that an incident/accident had the writing on the wall while ever ANZ operated the flights in the manner that they were. If it wasn't Captain Collins and crew and passengers, it would have been another unfortunate flight.

[Graybeard]

NCU

The NCU received attitude and position data on serial busses from the three LTN-58 ISU, Inertial Sensor Units, which, of course, had very sensitive accelerometers. It was undoubtedly an Arinc 561 word format, but I don't recall the data rate. Eight times per second is reasonable.

Time and distractions confused my memory on the altitude. As Brian wrote, 700 feet radio altitude was the trigger for the GPWS.

GB

[Graybeard]

"prospector, it would seem you have little understanding or appreciation of the hazards revolving around operations in the polar regions, else you would not be making that statement. You're not to be faulted for that of course. And it's the reason I keep saying that an incident/accident had the writing on the wall while ever ANZ operated the flights in the manner that they were. If it wasn't Captain Collins and crew and passengers, it would have been another unfortunate flight."

If this flight had not crashed, the pilots would have surely reported the error in their position vs. where they believed they were. That would have caused a major stir at HQ.

For examples:

If they had continued on course from Hallett a few seconds longer, they would have made radar contact with McMurdo Station, and been told they were just north of Erebus.

If they had turned on their Wx radar upon making their descent below 16,000, they would have seen the position error.
-------

As I pointed out in one of my first posts here, using the word McMurdo without attaching Station or Sound was a deadly confuser.

GB

[prospector]

" prospector, it would seem you have little understanding or appreciation of the hazards revolving around operations in the polar regions"

Not first hand, but I have seen numerous photo's, especially of Erebus,from many miles away, I have heard it stated it can be seen from 100 miles away. This is in CAVOK conditions with the atmosphere gin clear.

If the mountain was never sighted at any time, as on this flight, when even if they were on the track they thought they were on they would have been no more than 20 miles from Ross Island, then surely alarm bells must have sounded.

This also from the crew that had never been to the Antarctic, apart from the Flight Engineer

"He levelled out at that height and a few minutes later, knowing from McMurdo that the weather was well below the minima required for the company approved letdown procedure and so he would have to improvise his own, he saw a break in the clouds which extended to sea level. Collins stated his intention to circle to get below cloud".


Once again go back to the purpose of the flight, sightseeing, what is the purpose of going down to 1500ft when you had been advised that the weather was no good for sightseeing??? in the McMurdo, Ross Island area???

Then come back to the apportioning of blame, that the aircraft impacted Erebus was totally the fault of the Nav Section in Auckland, and the crew were completely blameless, this according to Mahon's findings?? no way will I and many others accept this reasoning of Justice Mahon's.

[ampan]

Retraction - Captain Wilson

At #223, #266 and #403 I said that Mahon labelled Captain Wilson as a perjurer. I was completely wrong about that. No such finding was made by Mahon – which explains why Captain Wilson was not involved in the Court of Appeal and Privy Council cases.

I’d like to carry on with this briefing business a bit longer, because I’m convinced that Captain Wilson told the crew that the nav track was to the NDB at McMurdo Station. What he didn’t tell the crew, or, more likely, didn’t make clear, was that the nav track was over Erebus.

If you accept that the pilots at the briefing were told that the final waypoint was at the NDB at McMurdo Station, what about the evidence of two of the surviving pilots concerning this rough “eye-balling” exercise they both allegedly carried out, where they estimated, they said, that the final waypoint was somewhere other than at the NBD at McMurdo Station? That could not have happened: If the briefing officer is saying that the waypoint is at X, and you think it might somewhere else, you would definitely say something.

The “eye-balling” evidence never made much sense in any event. It’s not the sort of thing you would expect a pilot to do during the briefing. You might do it home afterwards, while flicking through the briefing documents. Or you might do it on the flightdeck. But during the briefing, you would be listening to the briefing.

But let’s do a cross-check: Assume that the eye-balling occurred. We know that none of the five pilots at the briefing raised an issue concerning the final waypoint. So these two pilots, having formed the impression that the final waypoint was not at the NDB at McMurdo Station, sat there and said nothing. There are only two ways that this could have happened. The first possibility is that Captain Wilson never made any reference to the nav track and completely avoided the subject – which possibility can be discounted. The second possibility is that Captain Wilson did refer to the nav track and indicated that it went somewhere other than the NDB at McMurdo Station, to a position that roughly accorded with the position that was estimated by the two pilots. But if this is what happened, you would expect the two pilots to say so in their evidence. They don’t. Instead, the subject is avoided.

So all five pilots walked out of the briefing room believing that the nav track was to the NDB at McMurdo Station – and one of them, Captain Collins, was holding a print-out of the flightplan, which he believed was to the NDB at McMurdo Station.

Capts. S and G. meet on the morning of their flight, collect the flightplan, and manually enter the waypoints, believing that the track they are entering will take them to the NDB at McMurdo Station. On reaching Cape Hallett, they find blue skies, and fly heading select, right of track, closer to Victoria Land. Once at the end of the sound, by the Dry Valleys, they turn left and head for McMurdo Station, which they can see. As they pass the Dailey Islands, Capt. S. notices that they are going left of track. This is unusual, because he didn’t expect to be going left of track until passing McMurdo Station – because he believes that the track goes to McMurdo Station. This concerns him, because there might be a problem with the AINS, which he has to rely on to get back to NZ. So he performs an update once over the TACAN. This is the point in time, I think, when the charts came out and when the eye-balling occurred.

[werbil]

Correct me if I'm wrong, but isn't a "cloud break procedure" a procedure designed to allow a descent through cloud to get visual beneath a layer? After completing the cloud break procedure terrain avoidance would still be visual, and impact at 6,000' in sector whiteout is just as possible, especially if you are not where you think you are. VFR procedures require the pilot to use visual observations to ensure separation from the terrain. Even just one minute after you have made a positive visual fix you are navigating using dead reckoning procedures, and if you're below the lowest safe the only source of positive terrain clearance information is by visual observation.

Prospector, the conditions you describe (sky clear) are far, far greater than CAVOK. It is my understanding that under a solid ceiling at 20,000' even with 100km visibility (also well in excess of CAVOK conditions in this location) "sector whiteout" could still occur with the same results. Unlike reduced visibility or cloud, you can't see sector whiteout coming - you can only recognize it when you are in it AND you are expecting it AND you know what signs (or lack of) that you are looking for.

Whilst the conditions may have been unsuitable for scenic viewing in the McMurdo area, the weather could well have been quite suitable a few miles away. Whilst I don't have any Antarctic nor Arctic experience, I do have a lot of experience in VFR tourism operations, and I would be very surprised if localized weather did not occur in these regions like it does everywhere else that I've flown. To condemn the crew based on the weather in another location (even if it was their eventual destination) is irrelevant.

Ultimately, there are numerous things that if the flight crew had done differently the accident would not have occurred on this particular flight. However, the same can also be said for Air New Zealand, the New Zealand Civil Aviation Authority (what ever it was called) and even the US military. Even the open door policy could well have distracted the crew at a critical time.

It is the company's responsibility to ensure that the flight crew are route qualified - and it is the company's performance is this regard that lined up many of the holes (the lack of detailed information on whiteout, the lack of information on the use and limitations of weather radar for ground mapping of surfaces covered by dry snow, the alteration of the waypoints combined with the ambiguity [polite way to put it] of the route in relation to Mt Erebus).

I still have some trouble with the concept that the crew should be completely exonerated for their contributions to the accident. At the end of the day a perfectly serviceable aircraft crashed into the side of a mountain, and if the crew's job is not to prevent that, what is it? However, given what I have read I am not comfortable to condemn the crew to being any of 'reckless', 'careless' or 'negligent' - the outcome proves that some of their decisions were wrong, but given the same training, briefings and company procedures without the benefit of hindsight would other professional pilots have done the same thing? I'm damn sure some would have.

W

[ampan]

Catagories of pilot conduct

I’ve got five categories of pilot conduct. First, there’s Silk Air deliberate. Second, it’s Cali Columbia reckless. Third, which is where we are at, is negligence. This is the “pilot error” zone. The issue is the conduct of the crew, measured against the objective standard of an average crew exercising a reasonable amount of care and attention.

Fourth is “Could have done better”. Fifth is “Couldn’t have done anything”.




If we look at the conduct of the flight from Cape Hallett onwards, there are three matters that can be classified as “Could have done better”. The first is the failure to appreciate the reason for the lack of VHF communications. The second is the failure to identify Beaufort Island. The third, which is connected to the first and the second, is the failure to check the current co-ordinates displayed on the AINS against the chart. But none of those failures, in my opinion, was pilot error. (Whether a finding of pilot error can be based upon an accumulation of “could have done better” factros is is an issue that will have to wait for another day.)

This leaves us with the decision to descend below the height of a known hazard without verifying the position. There would be no argument if the descent was through cloud. But it wasn’t. Prospector and the other aviation experts he cites say that it makes no difference. But I can’t get past the logic of Brian Abraham’s “VMC bubble”. In other words, your own eyes give you a spherical zone of protection against hitting the high ground. As it turned out, the VMC bubble was an illusion. Although the captain, who was obviously an aviation buff, was aware of the phenomena of sector whiteout (“bit hard to tell the difference between the ice and the cloud”), that does not mean he would know it when he saw it. All he had done was read about it. So I can’t call the decision to descend an error.

Then we have the alleged breach of an alleged rule re minimum altitude. But to establish an error based on the alleged breach of a rule, you first have to establish the rule. That can’t be done in this case – see the various Desert Dingo postings.

So I come back to the night before the flight, when the captain plots the nav track, after being told, 18 days beforehand, that the nav track was to the NDB at McMurdo Station. He would have noted that a track to the NDB at McMurdo Station would go over Erebus. He would have noted that the copy of the flightplan gave a track going to the Dailey Islands, which would not go over Erebus. He would have noted the conflict between what was said at the briefing and what was recorded in the briefing documents. What occurred, I think, was that he disregarded this potential issue concerning the final waypoint and went to bed that night completely confident that his nav track was well to the left of Erebus. That was an error, in my opinion. It was perpetuated the following morning, when the captain confidently advised F/O Cassin that the track did not go to the NDB at McMurdo Sound. Although the F/O has the most difficult job on the flightdeck, F/O Cassin should have questioned the captain, given that F/O Cassin would have remembered Captain Wilson’s comments re the nav track. Instead, he went along with the skip, so no-one checked.

[prospector]

werbil,

"To condemn the crew based on the weather in another location (even if it was their eventual destination) is irrelevant."

Considering Mt Erebus was hiding amongst this weather your statement of irrelevance is to say the least puzzling.



" It is the company's responsibility to ensure that the flight crew are route qualified"

If you have been following this thread you will no doubt have noticed that it was demanded, requested , or at any rate required from NZALPA that their members all be given a turn on this perk flight to the Antarctic. This in complete disregard of the experience in Antarctic operations demanded by all other operators going down there, RNZAF, USAF, USN, etc. While this may be seen as a fault of the company surely it must also be considered when blame is apportioned for this event.

It was not, as has been described by NZ's most experienced Antarctic operator, a Sunday drive, with up to 11 people believed to be in the cockpit at the critical time.

"limitations of weather radar for ground mapping of surfaces covered by dry snow, the alteration of the waypoints combined with the ambiguity [polite way to put it] of the route in relation to Mt Erebus)."

That is a theory of Mahons, it is not held by everybody, and there was certainly plenty of rock faces to give a good return from Beaufort Island, and as has been said many times Beaufort Island, if they were on the track they thought they were on, was on the wrong side.

By going VMC descent they took responsiblity for their own terrain clearance, they impacted terrain, how can that impact then be seen as anybody elses failing??? They were well aware of their lack of Antarctic experience, surely one would be ultra careful, and not do such things as design own descent procedure in marginal weather in that location.

[ampan]

"We Are Going To Get It Right"

I can see where you're coming from, Prospector, but that VMC argument is a bit like the "PIC" argument: the captain must be at fault because the aircraft hit the ground. That's like saying that the captain in the O'Hare accident has to cop a share of the blame.

Am wondering if Gary Parate might still be lurking out there. In any event, on 16 February 2008 he said this, at #248:

Quote:
"Incidentally, if ALPA are going to do are proper job on the proposed website, why don't they dig up everything, scan it, and put it on the site so that everyone has all the information? "

As one of the webmasters for the new site, I can confirm that this is exactly what is going to be happening. The site will be short on opinion, and long on information, although ultimately the judges of that will be you. Many of the questions on this thread will be answerable by researching the site. I don't yet have a date for when the site will go live, possibly April/May but I can tell you that this thread is having an influence on its ongoing development because it is serving as a useful barometer as to the necessity of having such a site.

The PC judgment has been scanned and will be available, as well as the Mahon and Chippindale Reports.

Other features will include a media kit, an area that will facilitate research, school projects, and a commemoration section.

It will not be a tool for venting one's spleen, nor should there be cause for anyone to vent at it(!), provided we have done our jobs correctly. Once again, that will be for you to decide.

A panel of experts will be available to answer questions by e-mail. All attempts will be made to ensure the impartiality of answers and I will be personally ensuring that this is the case. Whether I succeed in your estimation is another matter.

I have no opinion on some of the opinions I have read here, preferring to value them as a valid contribution to a robust debate. However I have to say that some of the statements of 'fact' I have read on here are nothing of the kind, and only serve to perpetuate myths that result in a debate that waste's everyone's time. Several claims that generate false thoughts in readers' minds that the Privy Council and the Court of Appeal "overturned" the Mahon Report are good examples.

It is hoped that the site will minimise pointless debate, but that may be wishful thinking. At least debate is better than no debate, and I, for one, have enjoyed reading every contribution on this thread. So keep it up, PPRuNers.

Gary Parata

All well and good, Gary, but I it is sometimes a little difficult to be assured of these things, especially when the following appeared in the President’s Message in the Dec 06 edition of ‘N’Formation’ (p10):

"The Jim Collins Memorial Award was presented to Capt.Paul McCarthy at the 2006 Conference held in Rotorua.While I (President) was away for the Conference, I did have the pleasure of informing Paul of his award. Paul was overcome and felt privileged to be considered worthy of such an award. Part of the process of determining a worthy recipient for this award is working with Maria Collins, Captain Jim Collins’ widow. What a pleasure this is, and what a vibrant lady Maria remains. Maria is passionate about this award initiated in recognition of her husband Jim Collins, Captain of TE901, tragically flying into the slopes of Mt Erebus in1979. Every day Maria still has issues she deals with concerning this tragic time for her family and New Zealand. Maria is determined that her grandchildren and their grandchildren, when researching this flight and Mt Erebus, will read that the Mahon Report is the accepted account of the flight in New Zealand’s records, at ICAO, and anywhere on the Web. We have been working with Maria to help this happen. Work on a comprehensive Erebus page on the NZALPA Website has been underway for sometime. We are going to get it right before we go live. You will see this page available next year and will be advised when it is available."

This is, obviously, a sensitive issue. But the question has to be asked: Are we going to get it right? The fundamental issue is whether Mahon’s exoneration of the crew was correct. Captain Collins, as pilot in command, was a key member of the crew. His conduct, therefore, has to be scrutinised and, if necessary, criticised. This criticism will be extremely distressing to his wife and children, and to his grandchildren. So I think NZALPA should make up its mind, one way or another. Either do it right, or don’t do it at all.

If NZALPA are to proceed, then these are the items that I would like to see on the website:

(1) A complete transcript of the evidence of Capt. Wilson, Capt. Simpson, F/O Gabriel and F/O Irvine.

(2) Any document containing any previous statement made by any of the above witnesses.

(3) The photocopy of the topographical map used at the briefing.

(4) The topographical chart provided in the despatch documents.

(5) The passenger photographs of Beaufort Island.

[prospector]

Ampan,

" I can see where you're coming from, Prospector, but that VMC argument is a bit like the "PIC" argument: the captain must be at fault because the aircraft hit the ground. That's like saying that the captain in the O'Hare accident has to cop a share of the blame."

Who made the decision to descend VMC?? they were in receipt of the local weather conditions.

Cant see any similarity with the O'Hare incident, that captain was faced with a problem of great magnitude and very little time to suss it, also nothing in the manual to cover such an event. How do you relate that to a decision taken with no time stress and in a perfectly functioning aircraft?

[ampan]

They knew the weather conditions, but they didn't know the effect that those conditions would have on their visibility.

If that descent had been made in a tropical or temperate zone, it would have been been a safe manouvre, wouldn't it?