Chinook - Still Hitting Back 3 (Merged)

[flipster]

It would be really confusing to read some posts without the others!

Omega V6 - I thought you were going to say that!!

Caz - OV6 is right about 'the get better soon' comment (at least some of my ramblings are alcohol induced)!
Sadly, however, I had no idea you were ill and I would never wish you or your family any harm nor ill-will, so condolences, old bean.
However, AA is also right - laughter is also the best medicine - so keep smiling, life is too short to be taken too seriously - I say that as a cat with only 4 lives left and my 'scrapes' have made me very aware how close to the edge we all live - which is why it is important to try to do the right things and not just do things right. Perhaps Wratten and Day should remember that?
Best of British Caz.

Now, back to thread........

VMC as defined by COCISOS (below 140kts for helos) is less limiting than COCISOS and 1nm horizontal viz which, as I say, I am sure are lims for mil VFR in the UKMLFS - it is these that the crew would have been working to as they coasted in. Now here is the difficulty - have any of you tried to measure the in-flight viz - how can you do so exactly? I know how to 'guesstimate' the viz but its pretty hard, especially over the sea, so lets cut the guys a bit of sensible slack and suggest they were using an element of experience and 'sphincter-tension'. However, I think that the yachtie's statement that he could see the ac at about 3-400ft is pretty clear evidence that, over the sea, the weather was VMC and so IFR was not required. Walter, I believe the waypoint change indicates that they were trying to avoid the Mull, not landing on it and perhaps any slowing down was because the weather was looking iffy? Nonetheless, you may well have a point - neither of us can say either way.

[Tuckunder]

Sorry to be a pain. I am an occasional pruner but have not read much over the last couple of years. I find it really sad that this thread seems to be plodding away without direction. Many of the recent threads are going over old ground of 2 years ago. Please don't get me wrong, John Tapper was a student of mine at Shawbury. He was very professional and a delight to teach and I have always been of the opinion that he and his crew have been the scapegoats for an accident that was possibly due to flying an aircraft that might not have been "fit for purpose". I doubt that we will ever know. I did all the recommended requests on PPrune years ago ergo writing to my MP, writing to that idiot defence secretary Hoon all to no avail. Is there anything practical we can do rather than just go over old ground repeatedly? John and his co-pilot deserve their names to be cleared.
Tuck.

[Boslandew]

VMC Limits

Thank you for your replies

However, the matter still remains unclear. Olive Oil quotes, with a reference, Helicopters below 140 knots, Clear of cloud, in sight of surface, (the other option, 1500 metres clear of cloud, 1000ft vertically and 5nm vis surely refers to flight above cloud and is not really relevant here)

Flipster, with a reference, quotes the same but with a requirement for 1nm visibility.

After posting my query, I had a brainstorm and found the MOD response to the Mull of Kintyre Groups report. (I'm not being a smartass, I had genuinely forgotten this source, happens when 65 kicks in.) There it states, a prescribed minima of 1 nm vis beneath a cloud base of 250', no reference given. Since the verdict must have been based upon this definition, how come no-one else seems to be aware of it?

There is a suggestion that SF crews may have had lower limits, presumably classified so I won't pursue it.

How can something so elementary as VMC have three different definitions?

[flipster]

Bos,

If you are looking for chapter and verse - JSP 318 (as was, now JSP 550) will probably reflect the civilian UK AIP (Civ Air Pilot) of 'COCISOS' for VFR. I don't have a current copy of either, so I can't confirm. Although I have re-read my CAA VFR Guide - which confirms that 'COCISOS' is the VFR limit for helos.

However, both JSPs, GASOs and the UKMLFS Handbook would, most likely, have added slight further restrictions to viz and/or cloudbase for military ops and trg (possibly both different!!). So one could be legally VMC/VFR (iaw AIP/JSPs) but not complying with mil limits/orders for low-level. As I say, it would take a bit digging to find out what all these were in 1994. I will re-check my notes but if someone knows, please speak up!


That said, I think it is reasonable to assess that the weather over the sea was better than '1nm viz and 250ft cloudbase' (which is the most limiting I have heard so far for helos) and so, the weather was suitable for continuing at low-level over the sea. Over the coast, near to the mull, I suggest that this was not so - but remember it is very hard to accurately measure in-flight viz from within the cockpit. The WP change indicates to me that the crew were 'visual' and intending to stay away from culmulo/strato-granite. Something interfered with this intention - but we don't know what, nor why and certainly 'with no doubt whatsoever'.



Tuckunder

I am sorry you feel that we are going round in circles but some posters have not been around this thread for that long. So, please bear with us if we catch up with you old stagers.

I think Tuc has pointed out that there were serious concerns with the Mk2's airworthiness (not addressed by the BOI) and that this case (among others) has parallels with the recent Hercules and the Nimrod cases - where the MoD have admitted liability. If you can see a link and feel that there may be the need for further investigation, then write to your MP and Mr Charles Haddon-Cave QC at the Nimrod Review to express your concerns. I have.

2 QUESTIONS that I don't think have come up before.

1. At the time of the crash, did the Mk2 sim fully replicate the aircraft?

2. When had either of the pilots attended Flying Authorisers' Cse (FLAC) or the Flying Supervisors' Course (FSC) at IFS, as it was?

[chinook240]

Flipster,

On the sim, yes it was converted to the Mk 2; 'faithfully' is always a subjective assessment.

On the weather limits HQ 1 Gp GASOs specified, if memory serves me, 100' cloudbase in exercise areas, 250' in the UKLFS and 500' outside those areas.

[Boslandew]

VMC

Olive Oyl

You've got me thinking again now

Am I right in thinking that the 1500 metres, 1000 ft and 5kms applies to aircraft above cloud and Clear of cloud/In Sight of the Ground to aircraft below cloud. If so, that is why I suggested that the former was not relevant in this case. I do take your point about flight above 140 knots (is that IAS or GS?)

The MOD reply to the MOKG report states that the limits for a helicopter above 140 knots is 1500 metres clear of cloud laterally, a 500' cloud-base as opposed to the 1000' vertically clear of cloud you mention(indicating below cloud) and 5kms vis,

Now Chinook240 mentions cloudbase figures of 100', 250' and 500' for various circumstances

I would be very hesitant to claim that I knew which figures were relevant in this case

As regards SF minima, again I'm way out of touch but I do know that, for example, the Westland Longbow Apache, is capable of flight in next to nothing and assumed that crews must be allowed to train in such conditions.

[Boslandew]

VMC

Flipster

Thank you for your detailed reply.

I have always been doubtful about COCISOS, would 100'/100 metres qualify??? I have vague recollections from my Air Corps service that there were additional limits imposed upon this and from more recent civilian service that the company I worked for imposed their own additional limits for overland and over sea flight. The need to stay more than 500' away from person/buildings etc meant that the practical minimum over land was 550'. A correspondent to this thread said that does not apply to the military.

Despite a lot of info over the past few days, I am still unsure which minima would have applied in the case in question

[chinook240]

Boslandrew,

The more restrictive of the rules would have applied to SH operating within the UKLFS ie 250' and 1km vis. When outside the UKLFS then it would have been 500'. COCISOS would not have applied as it was less restrictive.

[walter kennedy]

Olive Oil
<<I believe the BOI accepted that this helicopter was cruising at an IAS in excess of 140 knots>>
I suggest you read Boeing's "Analysis of Available Data" (author Mitchel) available on the web.
It is the only decent analysis done by any authority.
It has that over the bulk of the flight (say, up to the position of waypoint change) the average air speed was at the full cruise speed of 135 kts - from waypoint change to impact, the calculated actual air speed would have been 120-125 kts.
There has always been a spin to suggest that the pilots were pushing it - read the early transcripts of the early inquiries.
To understand this crash you have to do the chartwork and distance/time analysis strictly.
Further, the Boeing analysis fits with the AAIB's conclusion that the SuperTANS had retrospectively been accurate over the critical phase and so the position at which the waypoint was changed can be relied upon and so is an important reference and therefore we can look at this position on a detailed chart and realise that it was very close in.
I say so close in that they would not have relied upon SuperTANS or DR or (difficult) visual judgment to have got that close in at their speed - that is why I believe they were referring to something else that ultimately misled them.

[cazatou]

Olive oil

Using the forecast wind speeds on the first leg prior to waypoint change there would have been a tailwind component of 9.2 kts at the surface and 24.5 kts at 2000 ft. The average groundspeed between the ATC fix leaving the CTZ to impact was 158 kts with a groundspeed at impact of the order of 150 kts.

Boeing calculated from the SuperTANS data, evidence of tracks on the ground and wind speed that the aircraft groundspeed was 162.8 kts with a heading of 017 degrees True. Airspeed immediately prior to impact was approximately 135 kts.

[Boslandew]

VMC

Olive Oyl

With respect, I put the relevant sentence into my own words but have not changed any figures. I was merely quoting the figures given by the MOD response to the MOKG I quoted. Herewith:-

"The Board members concluded that the prevailing weather conditions were such as to demand flight in accordance with Instrument Flight Rules (IFR) in the vicinity of the Mull of Kintyre. The prescribed minima for flying visually, VFR, are horizontal visibility of 1 km beneath a cloud base of at least 250 feet, if flying below 140 knots; and a visibility of greater than 5kms, 500ft minimum cloud base, and 1500 metres horizontally from cloud, if above this speed.

I don't know what I have misinterpreted. The case I did quote where I could not remember the details, anno domini again, I asked you to confirm that I was correct.

[Chugalug2]

Olive, I find it interesting that having expressed your views about the general lack of understanding by professional pilots about what actually constitutes flight in accordance with Visual Meteorological Conditions, and thus their subsequent fall from grace at later BoIs etc, your rejection of Boslandew's offering was swiftly countermanded when it was pointed out that he was repeating an MOD statement. Are their words sacrosanct in your view? As you seem now to be satisfied as to the VMC rules pertaining at the time and of the IAS of the Chinook could we share your satisfaction? Do you think that the aircraft was maintaining VMC and a normal airspeed in transit, or was it IMC and also high speed due to Crew Duty Time limitations, or like most of us demented professional pilots, past and present, do you just not know? Also what do you understand by the BoI quote:

The Board members concluded that the prevailing weather conditions were such as to demand flight in accordance with Instrument Flight Rules (IFR) in the vicinity of the Mull of Kintyre.

No one to my knowledge challenges the view that the Wx at impact was very IMC, but the general consensus (I think) is that was restricted very much to the Mull land mass, not to its "vicinity"? What does the BoI mean by vicinity? Or was that a cleverly ambiguous use of words, you know like the MOD is fond of?

[Tandemrotor]

I appreciate the conjecture (based on 'back of a fag packet' circumstantial evidence) surrounding the weather, and of course the reasons some would wish it to be accepted as a 'factual' allegation, regarding the conduct of this specific flight.

Would some kind soul point me in the direction of the evidence that proves (conclusively) the crew 'broke' the weather limits for flight in accordance with VFR?

And particularly so prior to waypoint change, since some contend THIS is where negligence occurred.

I encourage you to state what 'standard' of proof your evidence satisfies: (you can choose 'balance of probability', 'beyond reasonable doubt', or the standard required in this case of 'absolutely no doubt whatsoever')

That way we can move on.

I'm obliged

[Boslandew]

Tandem

I think you're being a little harsh there. Nine or ten witnesses on the Mull, including two trained met observers and someone who estimates he was 100 yds from the crash site said that the Mull was in fog. I don't think its a question of anyone 'wishing' that to be accepted as factual evidence so much as seeing no reason not to accept it as factual.

As regards going below the weather limits for VFR, much though it pains me to have to mention it, the aircraft did crash into terrain which nine or ten witnesses stated was in fog.

As regards to prior to waypoint change, I don't know, which is really at the heart of the matter since the verdict was based upon just that.

As regards to standards of proof, unless you question the veracity of the witnesses, it seems to me that there was absolutely no doubt that the actual crash occurred in met conditions below those required for flight in VFR even if the aircraft was flying below 140 knots. However I have been following this thread for long enough to know that someone will suggest ( or try to ram down my throat) a flaw in that argument and if they do convincingly, I will accept that.

[Vertico]

Boslandew

Not trying to ram anything down your (or anyone else's) throat, but can you be sure (ie beyond any doubt whatsoever) that it was a CFIT? Is it not at least possible, to put it no more strongly, that for some reason unknown to anyone now alive it was a UFIT? (Uncontrolled Flight Into Terrain)

[pulse1]

And particularly so prior to waypoint change, since some contend THIS is where negligence occurred.

This is where Bill Wratten (Pilot magazine article)contends that "gross negligence" occurred and is, as Boslandew says, the heart of the matter.

In the last nine years that this thread has been running, no-one has been able to say, with absolutely no doubt whatsoever, what the flight conditions were at waypoint change.

But Bill Wratten's stated view is that they were approaching the bad weather at too high a speed. So what speed is too high? Is it the only speed mentioned in the rules i.e 140 kts? Or is it some arbitrary figure based on the conditions. And what was their speed at this point? If we take the lowest estimated airspeed, was that too high for the prevailing conditions?

So, the heart of the matter is based on two factors, flight conditions at waypoint change and speed. And these must be considered together because that is what Bill Wratten has done. (Remember his motorcycle in fog analogy?)

Nine years of debate on this thread, together with evidence from the BOI, FAI and HoL, have convinced me that there is considerable room for doubt on both of these factors.

[cazatou]

Pulse1

In his evidence to the HOL Committee Sir John Day stated the following:

"If they could see the cliffs at a range of 1km, I am convinced that no reasonable pilot would have then flown straight on towards the rapidly rising high ground before intending to turn left along the line of the cliffs whilst remaining below the cloud base.

If, on the other hand, they sighted the cliffs at 1km range and intentionally decided to proceed straight ahead and cruise climb on track over the mountain, the pilots actions would have amounted to recklessness, which is a more severe degree of negligence than Gross Negligence."

[Chugalug2]

Pulse 1:

Nine years of debate on this thread, together with evidence from the BOI, FAI and HoL, have convinced me that there is considerable room for doubt on both of these factors.

Nice bit of good old British understatement there, old boy, if I may commend you. For those who complain that this thread is going nowhere these days may I reiterate Pulse's point and add to it that there is also little room for doubt, thanks primarily to this thread, that the aircraft was unairworthy. Indeed it would appear that was the case for all of its short (barely 50 flight hours) life, in company with its sister Mk2's. So an unairworthy aircraft proceeds on a low level VFR transit flight across the North Channel, planning to turn left to parallel the west coast of Kintyre but instead crashes into its mist covered hillside despite its pilots being experienced SF trained ones. The subsequent BoI and senior RO's ignore or are ignorant of the airworthiness shortcomings (in the BoI's case primarily because the RAF Odiham Test Pilot who had much personal experience of them was ordered not to speak to the BoI) and instead bizarrely decide that the transit was high speed in IMC despite eye witness evidence to the contrary. As has been stated above the aircraft crashed in IMC, into the mist shrouded Mull hillside, but there is compelling evidence that such conditions existed purely on that land mass and did not extend into the "vicinity" of the Mull. The inference of the above scenario to my mind is that when the aircraft entered IMC it was under little or no control. Do I have evidence for that? No, other than the aircraft was unairworthy anyway but then there is no evidence to say that it was CFIT either. Room for doubt therefore. No Gross Negligence on the part of the deceased pilots therefore. As to Gross Negligence by others, elsewhere....

[pulse1]

caz,

What does the word "if" imply to you?

Olive Oil,

It was his article in the October 1999 Pilot Magazine. I don't think that there was ever a link to it.

[flipster]

pulse

You are bang on! As I have said a number of times, the best appreciation of the weather over sea - approximately where the ac was at WP change - was that assessed by the yachtsman (1-2 miles off shore). The ac was visible (ie below cloud) at about 3-400 ft (probably more) and the visibility was hazy about 1nm - very much VMC (by JSP/AIP definition ie COCISOS) but probably close to mil UKMLFS limits for Low-Level flight. Therefore, the crew were probably not negligent before the waypoint change.

The fact the ac crashed into the Mull in cloud is indesputable. The fact that the ac probably climbed into cloud is also almost certain. What no-one knows, is what happened between the WP change and the crash, nor why the ac climbed and, certainly, whatever did happen cannot be proven with the requiste burden of 'with no doubt whatsoever'.

What worries me about the RO's logic is that the BOI report 'cannot discount the possibility' of technical failure, control restriction, distraction, visual illusions yet then discounts these statements in their series of 'possible rates of climb scenarios'. Ultimately, they say there are a number of possibilities and uncertainties but then go on to postulate a 'probable' cause.
Flawed logic perhaps - cherry picking maybe?

Either way, the ROs had no basis on which to find 'gross negligence' with the required burden of proof.