50 replies to this topic

[Alan Cox]

Knowing that a fair proportion of TNFers have an interest in British aviation matters, the following programme scheduled for this coming Sunday 24th February at 8pm may be worth a watch
http://www.channel4....sh-air-disaster
http://www.channel4....sh-air-disaster

(Reading the links I see that there appears to be an element of the dreaded 'docudrama' with some 'reconstructions', which always makes me fear the worst as they so rarely add anything to the story, but I shall live in hope..)

Edited by Alan Cox, 19 February 2013 - 16:01.

[Allan Lupton]

Knowing that a fair proportion of TNFers have an interest in British aviation matters, the following programme scheduled for this coming Sunday 24th February at 8pm may be worth a watch
http://www.channel4....sh-air-disaster
http://www.channel4....sh-air-disaster

(Reading the links I see that there appears to be an element of the dreaded 'docudrama' with some 'reconstructions', which always makes me fear the worst as they so rarely add anything to the story, but I shall live in hope..)

If this is in any way related to a previous Channel 4 "documentary" of 13 June 2002 called "Comet Cover-up" there was a lot of deliberate misrepresentation masquerading as revelation which means that I shall never ever take anything in a Channel 4 documentary seriously again.
Don't just take my word for it but read what the Broadcasting Standards Commission decided:
Summary on page 4 here

[Doug Nye]

Despite having been an instinctive, lifelong De Havilland fan, one must admit that the company's design engineering proved a serial offender over many years. The litany of in-flight structural failures involving DH airframes in fatalities over many years is difficult to condone. In period, however, a large proportion were simply typical of the emergent industry at large.

DCN

[Allan Lupton]

Despite having been an instinctive, lifelong De Havilland fan, one must admit that the company's design engineering proved a serial offender over many years. The litany of in-flight structural failures involving DH airframes in fatalities over many years is difficult to condone. In period, however, a large proportion were simply typical of the emergent industry at large.

DCN

I don't need to start an argument, but I'm baffled that you can refer to a litany of fatal in-flight structural failures. The Comet 1 certainly suffered that way, but what other examples are you including?

That Channel 4 "documentary" accused de Havilland of deliberately defying warnings and postponing recommended tests to the fuselage which would have saved passenger lives, and backed that up by using bits of interviews with many senior people edited to reverse the original meaning. Whether you are an old de Havilland man (I am) or not, the prejudice and simple unprofessionalism of the programme maker must be unacceptable.

[f1steveuk]

DH110?? Three Comets in the first year of service? 12 Comets crashing in total, eight of them in ten years?

Edited by f1steveuk, 19 February 2013 - 17:48.

[D-Type]

To keep a sense of perspective, how do these statistics compare with the Comet's [more or less] contemporaries: the Caravelle, Boeing 707, the DC8 and the TU 104? Taking into account the number of each that were flying of course.

[Doug Nye]

I don't need to start an argument, but I'm baffled that you can refer to a litany of fatal in-flight structural failures. The Comet 1 certainly suffered that way, but what other examples are you including?

I suppose one could argue that structural deficiencies in surviving adverse aerodynamic effects are due more to aerodynamic than structural shortcomings. However, wing collapses afflicted the DH52 in 1922, the DH75 Hawk Moths suffered several undercarriage collapses, 1928-30ish, and the DH80A Puss Moth featured in nine terrible accidents, one of which took the life of Bentley Boy Glen Kidston in 1931 and another killed Bruce Bossom and his two passengers - his Mum and a young German Prince on his first visit to England - when they "fell to earth" on Hankley Common, within sight from my window here, in 1932. These Puss Moth disasters were ascribed to wing flutter and wing collapse. The DH86 four-engined biplane airliner also had a luckless launch - Holyman Airways' first vanishing off the Australian coast in 1934 with Victor Holyman himself and 11 others, then a second DH86 crashing on its ferry flight to Australia...structural changes following, in particular to the tail fin. Holyman's second DH86 also fell fatally into the sea in 1935. The gorgeous DH91 Albatross second prototype broke its fuselage during overload tests on its third landing and structural mods were made to its sisters to prevent any recurrence, etc. Still this wonderful outfit produced some of the most beautiful, handleable and enduring aircraft the British industry ever conceived.

Born too late to be a genuine 'Hatfield Boy' the heir to my overdraft got an aerospace engineering Hons degree First at Hatfield which has stood him in good stead ever since. I am not at all anti-DH but their record pre-Comet was NOT without blemish.

DCN

Edited by Doug Nye, 19 February 2013 - 22:30.

[Allan Lupton]

Thanks Doug for your thoughts - I must say my knowledge of the light aeroplane accidents is slight. I did meet a man who was closely involved in the introduction of the DH 86 into QANTAS service and the concerns they had and changes they made were non-structural.
Glad to hear that the successor to Hatfield Tech. was still offering aerospace whenever it was your son needed it! A lot of us did the academic part of our training there, and there were some very clever things developed by some and pretty competant stuff by the rest. e.g. the aerodynamic design of every Airbus wing has its origins in the Hatfield design team.

The DH110 has to be accepted in that it did suffer in-flight structural failure, and very publically too.
Of the 12 Comets that Steve offers, without going through them in detail, I'd say only the three Comet 1s were attributable to in-flight structural failure.

I can't offer comparisons without doing the research, Duncan, but most of the fatal accidents to the other types mentioned were not caused by structural failure.

[f1steveuk]

A massively "in depth" subject if one was to go delving, and I accept that not all Comets crashed because of structural failings, and I left out the two Comet 1s that failed to take off (intake stall at high angle of attack), but it still doesn't make good reading, plus the public at large don't really care, their concern is, "is it safe?".

There was some talk that design errors had been carried over into the Comet based Nimrod?

I think it's pretty much accepted that the failings of the Comet 1 were at a time the knowledge and understanding of metal fatigue were pretty much in thier infancy, unless I have read the books wrong?

Edited by f1steveuk, 20 February 2013 - 16:51.

[Allan Lupton]

I think it's pretty much accepted that the failings of the Comet 1 were at a time the knowledge and understanding of metal fatigue were pretty much in thier infancy, unless I have read the books wrong?

Yes, now unfortunately textbook examples of fracture mechanics. Crack initiation and propagation on plane's square windows.

Yes that is the case, and those companies which were slightly behind were able to benefit before they built what they were making.

My concern, introduced above, was that this programme would be a version of Channel 4's previous hatchet job where journalists, 50+ years after the event, implied that the state of knowledge and understanding was greater than it was, and that knowledge had been deliberately and culpably ignored by the company and its staff for commercial gain.

[f1steveuk]

"where journalists, 50+ years after the event, implied that the state of knowledge and understanding was greater than it was, and that knowledge had been deliberately and culpably ignored by the company and its staff for commercial gain".

Never was a truer word spoken!

[Doug Nye]

Aah yes - Television. Latch on to incidents and controversies more than twenty years ago - make out that nobody else has ever heard of them - furthermore make out that the story has therefore been suppressed or hidden away - and then present it all re-heated and skewed to infer, or state, malice aforethought - often with the security of the prime personalities involved no longer being around to blow the whistle upon the programme makers. And should any subsequent enquiry be made into the programme making processes and decisions, why...then they just redact any critical passages. One might be forgiven for suspecting that one has trodden in better...

DCN

[Allan Lupton]

Well it was not as bad as I feared, but had to be padded out to make even the shortened hour that an advertising channel uses.
There was the obligatory frenetic young woman waving her hands around and offering unhelpful (and inaccurate) "social history" comments; the "re-enactment" conference table littered with files and surrounded by people including one who we were supposed to identify as Arnold Hall despite the lack of physical resemblance.
However there were good contributions by Roger Topp who flew the RAE tests, and John Farley who brought the test pilot's understanding and perspective to the programme.
A good touch was to have Phil Birtles showing us round the actual Comet I fuselage they have at the de Havilland Heritage Centre.

[kayemod]

There was the obligatory frenetic young woman waving her hands around and offering unhelpful (and inaccurate) "social history" comments...

Yes, wasn't she awful?

Apart from her, I quite enjoyed the programme, not over-dramatised, and not too much wise-after-the-event allocation of spurious blame against people long dead.

[AAGR]

When is the British TV community going to start making grown-up programmes for grown-up viewers ?

AAGR

[Vitesse2]

There was the obligatory frenetic young woman waving her hands around and offering unhelpful (and inaccurate) "social history" comments ...

Dr Kate Williams. An odd choice, I thought, given that her real specialist period is the nineteenth century - although her contribution was presumably solicited on the grounds she's recently written a book on the early years of the present Queen and was consequently all over TV during the jubilee. So she must know all about the 1950s, eh?

Or maybe Juliet Gardiner and David Kynaston just weren't available?

[john winfield]

When is the British TV community going to start making grown-up programmes for grown-up viewers ?

AAGR

The television world does seem obsessed sometimes by the need to entertain, terrified that we viewers might find a subject too challenging, boring even! BBC Radio is still prepared to take risks with intelligent programmes; I'm often impressed by the Melvyn Bragg / In Our Time series, where the bright and knowledgeable Melvyn prompts experts to tell us what they know about a given topic. In Living Memory can be good too.

Edited by john winfield, 25 February 2013 - 10:30.

[Nick Savage]

At least the programme gave due credit to Sir Arnold Hall who was an inspiring character and developed a relatively simple and unequivocal test rig to cycle the Comet airframe. Though I doubt he personally tried to fry pork in avtur - an odd bit of re-enactment.

Dr Kate Wotsit was just so wrong on practically every utterance, but at least listening to her gave a good cardiac workout as my blood pressure soared. The metallurgy Prof did not add a lot to the narrative. They could have used Mike Ramsden (ex-Editor of Flight) a bit more.

The mix of Comet 1 and Comet 4B film was a bit pathetic ('oh good - colour film ! let's use that') but no-one seems to be able to afford expensive picture researchers any longer.

I had another look at the AIB Accident Report. While the narrator was correct to say that pressurisation-induced fatigue was unknown territory at the time, it was also a fact that lack of inspection and poor placing of rivet holes around the windows was a De Havilland manufacturing error. I would echo a previous post that said that De Havilland could be rather slapdash at that period - and I am a signed-up member of the "Ah ! De Havilland ..." fraternity.
Nick

[JtP1]

It is very easy to be wise after the event. It must be remembered that common use all metal aircraft were less than 20 years old. De Havellind had just entrered metal aircraft construction, the Mosquito being made from wood basically because that is what De Havellind made aircraft from. The other side of that coin in the Luftwaffe asking Junkers for a wooden aircraft, Junkers being the first German aircraft manufacturer to build an all metal aircraft. Pressurised aircraft were less than 10 years old.

Metal fatigue is not that well understood at that time, less than 10 years since Liberty ships falling in two. That being a combination of poor steel and design with welding allowing the faults to show up. I found it interesting that it was the windows on the cabin roof that were the failure point and not the side windows, thus much harder to spot on the ground.

The other thing not allowed for at the time was the rapid ground cycling of jet aircraft over that of piston engines, thus many more pressure cycles. That still not being considered with the Hawian 737 until failure.

[Allan Lupton]

Whilst de Havilland did make most of their previous aeroplanes from wood and were rather good at it, the pre-war Flamingo was all-metal, albeit unpressurised. What was not touched on in the programme was that professional structural engineering opinion at the time was that fatigue strength could be demonstrated by "static" strength. They pumped up one test section to twice normal working pressure (P). If it had failed at less than 2P, which it didn't, it would have been back to the drawing board.
Arnold Hall's recognition that nothing but cyclic loading can simulate cyclic loading was the great step forward.

The failure area was not as well made as it should have been - when a complex metal structure like that is made mistakes happen and rather than scrap a large assembly for a small error a repair scheme would be devised. I cannot say categorically that that was the case with Comet Is, but when we were building Comet 4s such schemes were often devised by the fitters concerned with the assistance of an appropriate inspector and only major repairs were referred back to the drawing/stress office.

The B737 in Hawaii, like many aeroplanes of that time, had been in service long enough for corrosion to have been severe so it wasn't a simple fatigue problem.

[D-Type]

Metal fatigue was not totally unknown to the aircraft engineering fraternity. Didn't Neville Shute feature a metal fatigue failure in his 1948 novel No Highway? Was the lack of knowledge limited to how to effectively test for the phenomenon?

[Odseybod]

Metal fatigue was not totally unknown to the aircraft engineering fraternity. Didn't Neville Shute feature a metal fatigue failure in his 1948 novel No Highway? Was the lack of knowledge limited to how to effectively test for the phenomenon?

Thanks, Duncan. I was just about to leap in with a cry of "What about Professor Honey and the Reindeer?"

[Allan Lupton]

Metal fatigue was not totally unknown to the aircraft engineering fraternity. Didn't Neville Shute feature a metal fatigue failure in his 1948 novel No Highway? Was the lack of knowledge limited to how to effectively test for the phenomenon?

Pretty well that.
As I wrote just now, static tests to a large overload were the norm.
What I can't remember is what system, if any, NSN had Professor Honey using but what he certainly recognised was that the number of cycles was an important criterion as it all hinged round the aeroplane they were in having clocked up the critical number.

[Bloggsworth]

Metal fatigue was not totally unknown to the aircraft engineering fraternity. Didn't Neville Shute feature a metal fatigue failure in his 1948 novel No Highway? Was the lack of knowledge limited to how to effectively test for the phenomenon?

James Stewart and Marlene Dietrich IIRC, and in America, No Highway In The Sky... Shute, of course, did all the stress calculations for the R100 designed by Barnes Wallis, the story of which is told in Shute's autobiography "Slide Rule."

Edited by Bloggsworth, 25 February 2013 - 21:02.

[D-Type]

I missed the programme. Does anyone know if its possible to find it on line or on one of thr repeat channels?

[Doug Nye]

Metal fatigue was not totally unknown to the aircraft engineering fraternity. Didn't Neville Shute feature a metal fatigue failure in his 1948 novel No Highway? Was the lack of knowledge limited to how to effectively test for the phenomenon?

July 14, 1954 proved such failures were not confined to De Havilland. The prototype Handley-Page Victor B1 lost its tailplane during a low-level pass at Cranfield and ploughed-in. its three-bolt tailplane fixing had failed, due to metal fatigue...

DCN

[Vitesse2]

I missed the programme. Does anyone know if its possible to find it on line or on one of thr repeat channels?

It's on 4OD, Duncan.

http://www.channel4....ter/4od#3485113

[D-Type]

Thanks V-2. I've now watched it and concur with the views expressed above.

[elansprint72]

July 14, 1954 proved such failures were not confined to De Havilland. The prototype Handley-Page Victor B1 lost its tailplane during a low-level pass at Cranfield and ploughed-in. its three-bolt tailplane fixing had failed, due to metal fatigue...

DCN

From what I read (a lifetime ago) metal fatigue in airframes was something of a concern from about 1937 onwards (in other metallic structures possibly from a hundred years earlier than that). Rather than point you folks towards obscure learned volumes, for once, I find that the dreaded wiki is almost completely adequate (for the layman) wrt this subject.
Typhhon airframe failure.
The typo here is not mine... stick with it boys...
Roly Beamont wrote quite a bit (from the driver's point of view) on this particular subject, from which the techies learned a great deal and thereby saved a good many lives.

Edited by elansprint72, 25 February 2013 - 22:35.

[ensign14]

When is the British TV community going to start making grown-up programmes for grown-up viewers ?

AAGR

Didn't they have a two-parter on BBC4 on the same subject a few months back that fulfilled the description? There are still such programmes, but usually tucked away. BBC4 is what BBC2 used to be, BBC2 is what BBC1 used to be, BBC1 is what ITV used to be, and ITV is programming for levels of intelligence that are barely above that of slime mould.

[Tony Matthews]

Dr Kate Williams. An odd choice, I thought...

I feel a bit sorry for her. I'm sure she realises that the only reason she was used was because the commissioning editor wanted an attractive female on the show. When I saw her in the trailer for the programme I decided to give it a miss. She is good on her speciality, and I don't blame her for taking the job.

[fuzzi]

Dr Kate Williams "She is good on her speciality, and I don't blame her for taking the job."

If her speciality is supposed to be royal family history, then you should hear my wife on her level of expertise.

[Alan Baker]

My own view is that this programme made "Comet Cover Up" (which I viewed again recently) look like a masterpeice. We will probably never know the truth about the Comet disasters. The water tank test failure occured at the equivalent of over 9,000 flight hours and in any case was not in the same place as the Yoke Peter failure. The aircraft involved in the Rome accidents had flown around one third of the hours of the water tank specimen, so either water tank testing is not a reliable guide or some other factor was involved. I have read in the past that some people have never been convinced that sabotage was not involved. It would not take a genius to work out who stood to lose out if the Comet programme had continued (the US airliner industry). It has always amazed me that, after the Hall enquiry had reported it's findings, it took another FOUR YEARS to get the Comet 4 into service, conveniently just a couple of weeks before the Boeing 707. Maybe somebody with more imagination than me could work up a rattling good conspiracy theory!

[Tony Matthews]

Dr Kate Williams "She is good on her speciality, and I don't blame her for taking the job."

If her speciality is supposed to be royal family history, then you should hear my wife on her level of expertise.

I humbly beg your pardon, Your Majesty... Well, that just goes to prove once again that 'experts' on subjects that we no little of appear much more knowledgeable than they are.

[Allan Lupton]

My own view is that this programme made "Comet Cover Up" (which I viewed again recently) look like a masterpeice. We will probably never know the truth about the Comet disasters. The water tank test failure occured at the equivalent of over 9,000 flight hours and in any case was not in the same place as the Yoke Peter failure. The aircraft involved in the Rome accidents had flown around one third of the hours of the water tank specimen, so either water tank testing is not a reliable guide or some other factor was involved. I have read in the past that some people have never been convinced that sabotage was not involved. It would not take a genius to work out who stood to lose out if the Comet programme had continued (the US airliner industry). It has always amazed me that, after the Hall enquiry had reported it's findings, it took another FOUR YEARS to get the Comet 4 into service, conveniently just a couple of weeks before the Boeing 707. Maybe somebody with more imagination than me could work up a rattling good conspiracy theory!

I shall not bother to object to your assessment of Comet Coverup as the Broadcasting Standards Commission found against it (see post 2 in this thread).
I can however point out that fatigue is cycle-dependent rather than hour-dependent.
The accident failure was not where the tank specimen failed but the principle was similar - something is bound to fail first and once there is a failure, the test stops. The water tank test proved an effective way to monitor aeroplane pressure hulls and was made mandatory by the certification authorities.
I can also comment that the Comet 4 had very little in common structurally with the Comet I and had a significantly longer fuselage, higher design weights and power and much more, so how you could expect it to be put in service sooner I cannot understand. Even getting the Comet 4 into service when it did was helped by using the Comet 3 as an aerodynamic prototype in part of the the flight development programme.

[f1steveuk]

My guess would be that Dr Kate Williams was in the programme because, if she waved her hands around any more, she would be able to fly, and the programme was about aeroplane's, other than that, she was a waste of air time.

[Macca]

She was very annoying, anyway (and irrelevant).......I grabbed the remote and was able to mute her most of the time.

The thing early on in the programme that made it questionable whether I'd watch it far enough in to be annoyed by her was that, in the CGI re-enactments, seemingly because they'd used the word 'explosion' they kept showing the aeroplane dissolving into a puff of smoke like a firework. Once the great 'revelation' of metal fatigue had been made, the last depiction of the loss of the first BOAC Comet correctly showed it breaking up.

But at least it was better than almost anything by the Snows, pere et fils.

Paul M

[f1steveuk]

She was very annoying, anyway (and irrelevant).......I grabbed the remote and was able to mute her most of the time.

The thing early on in the programme that made it questionable whether I'd watch it far enough in to be annoyed by her was that, in the CGI re-enactments, seemingly because they'd used the word 'explosion' they kept showing the aeroplane dissolving into a puff of smoke like a firework. Once the great 'revelation' of metal fatigue had been made, the last depiction of the loss of the first BOAC Comet correctly showed it breaking up.

But at least it was better than almost anything by the Snows, pere et fils.

Paul M

That may have been because several of the Italian witnesses said they saw an explosion, plus that gave the production company the chance to show how they had got history right!

[RTH]

My guess would be that Dr Kate Williams was in the programme because, if she waved her hands around any more, she would be able to fly, and the programme was about aeroplane's, other than that, she was a waste of air time.

I thought she was quite the wrong choice, the arm waving , the shouting and distracting unruly barnet took away from the seriousness of the content.
Good programme spoilt by the endless long advert breaks and time wasting recaps all the time.
Pity it was not handled by BBC 4 I feel sure quality would have been in a different league.

[RS2000]

Pity it was not handled by BBC 4 I feel sure quality would have been in a different league.

Hopefully not the league of the Dakar programme the other night or the earlier appalling "Group B" programme.

[D-Type]

There have been loads of comments on the presentation of the programme (with which I wholeheartedly agree) but I don't think there's been a single comment on lack of factual accuracy.

Edited by D-Type, 26 February 2013 - 20:59.

[Sisyphus]

Can't be too hard on De Havillands as metal fatigue was not very well understood in those days.

Remember that Aloha Airlines 737 lost it's top in 1988 due to the same metal fatigue (and it was not the only fatigue failure in an aircraft post-Comet). At least it was able to land and only the poor flight attendant that got sucked out of the airframe died. That the airframe stayed together owed a great deal to what was learned from the Comet experience which allowed the cracks to be relatively isolated and not take the entire structure apart.

Gerry

[Tony Matthews]

"The Railway - Keeping Britain on Track", BBC2, #3 of 6. OK, not investigative, perhaps, but NO visually intrusive presenter, just Kevin Whatley's meliflous tones, and real people, real events. An engrossing hour. It can be done well...

[Alan Cox]

"The Railway - Keeping Britain on Track", BBC2, #3 of 6. OK, not investigative, perhaps, but NO visually intrusive presenter, just Kevin Whatley's meliflous tones, and real people, real events. An engrossing hour. It can be done well...

So far, all three programmes have been excellent

[Odseybod]

So far, all three programmes have been excellent

I'd also stick my nose over the parapet and recommend Channel 5's "Beat the Ancestors". on the strength of last night's episode about the multi-barrel medieval cannon (and also because I've enjoyed Dick Strawbridge since his debut in Scrapheap Challenge). If nothing else, it has an interesting display of facial hair variations.

[Mallory Dan]

So far, all three programmes have been excellent

Agreed Tony & Alan, they're very good. Don't they confirm the old cliche though, that the railways would run so much better without passengers. I feel for the railway staff having to deal with the Great British Public: drunks, cowardly suicide merchants, yobbish youths, rude middle-ageds and just the downright thickos. The Old Boy at Twyford, what a great character!

[kayemod]

I feel for the railway staff having to deal with the Great British Public: drunks, cowardly suicide merchants, yobbish youths, rude middle-ageds and just the downright thickos.

You have to admire their restraint certainly, but it made me wonder if there were a few less PR-worthy incidents that got edited out.

[Tony Matthews]

... it made me wonder if there were a few less PR-worthy incidents that got edited out.

You cynic, you!

[Collombin]

"The Railway - Keeping Britain on Track", BBC2, #3 of 6. OK, not investigative, perhaps, but NO visually intrusive presenter, just Kevin Whatley's meliflous tones, and real people, real events. An engrossing hour. It can be done well...

Agreed, though at first I did think the dead dog looked like a left over prop from A Fish Called Wanda.

[coupekarter]

I had another look at the AIB Accident Report. While the narrator was correct to say that pressurisation-induced fatigue was unknown territory at the time, it was also a fact that lack of inspection and poor placing of rivet holes around the windows was a De Havilland manufacturing error. I would echo a previous post that said that De Havilland could be rather slapdash at that period - and I am a signed-up member of the "Ah ! De Havilland ..." fraternity.
Nick

Interesting you should say that.........When I started working at BAe Hatfield I was working for an old boy who'd been there since the 30's. He said that there was a bit more to the Comet problems than just the metal fatigue and square window issues that were publicised......apparently after one of the crashes when they were looking for the cause, they went into the factory and removed the window frames from some of the aircraft in production, and found that the window apertures in the skin had been chain drilled out and it was just left like that, hidden by the window frame!