Talk:De Havilland Comet

Comet fiction?

The story of the Comet is obviously foretold by the book No Highway by Nevil Shute and subsequent movie No Highway in the Sky (the movie stars Jimmy Stewart), much the way that the story of the RMS Titanic was foretold by the novel Futility. Is there any place for this in this article, since this is obviously speculative, but nonetheless fascinating?

Rlquall 18:06, 14 Oct 2004 (UTC)

C.102

Boeing's 707 was abetted by stupid decisions by TransCanada Airways (now Air Canada) not to buy the Canadair C.102 Jetliner (a term coined for her), which followed the DH.106 in August 1949, and by the Canadian Government's Ministry of Supply ordering the company to concentrate on building CF-100s for the Korean War. (Or so C.102 partisans argue...) Trekphiler 19:42, 2 December 2005 (UTC)

The internal link "De Havilland DH-108 Comet" is in error as the DH-108 is the Swallow high speed test aircraft.

Mistake

Hi, 'm a French wikipedian and I work on the translation of this article. I wanted to add some informations, so I searched on the web to find precise dates about the 3 DH-106 crash. And I found these 3 dates on the BBC website :

Comet crashes in the 1950s 3 March 1953: Canadian Pacific Airline Comet crashes on take-off from Calcutta airport killing 11 people on board due to pilot error 10 January 1954: BOAC jet crashes off the Mediterranean island of Elba killing 35 people on board 8 April 1954: South African Airways Comet crashes en route from Rome to Johannesburg - all 14 passengers and seven crew die.

http://news.bbc.co.uk/onthisday/hi/dates/stories/january/10/newsid_2709000/2709957.stm

I also found this

http://aviation-safety.net/database/record.php?id=19530502-0

So, how many crash were they and what are the real dates? If somebody has got an answer, you can reply here

http://fr.wikipedia.org/wiki/Discussion_Utilisateur:Tatane

Cracks at the ADF Aerial hatches as well?

I thought that the Elba accident were caused by cracks in the ADF aerial hatches at the top of the aircraft, and that the windows only cracked at the pressurisation tests??

--60.234.137.41 00:10, 18 April 2006 (UTC)

This is the finding of the report. Incidentally, the ADF hatches for the aircraft still exist, and are in the Science Museum collection, having been moved from Farnborough's museum some years ago. Bearing in mind the theories being espoused below, I am sure they could be tested, even today, for evidence of the decompression being caused by an explosion. Brucewgordon 17:01, 14 February 2007 (UTC)

Start class rating

You're having a laugh; from my reading of the quality scale it's B-class.GraemeLeggett 11:30, 10 August 2006 (UTC)

• B it is then. - Mailer Diablo 12:33, 10 August 2006 (UTC)

Comet Sabotage

I agreee that further citations are needed, and now I've worked out how the footnotes work they will be added, during the course of this week. Some additional tidying is also needed.

I am a trial lawyer (that's my day job!), former immigration and political asylum judge and intelligence specialist, teaching Intelligence Studies at Masters level to inter alia serving intelligence officers. I have also acted as intelligence consultant to the BBC TV program Spooks, broadcast as MI5 in the USA, ie I inhabit the twilight world between the spook shops and the media. I knew Markus Wolf, who was DVD (he was only paid by the HVA!).

With Ray Baxter's help (he is a sad loss) I have been researching what I hope will be a major new book on the Comet, although of course I have not referred to that in the article. I have a number of citations to add in during this week.

There is no doubt these airliners were blown up by the DVD, and equally no doubt that Boeing and CIA were completely innocent of any complicity.

The Germans have privately admitted responsibility to us (it was they who gave us the name of Hertzog, who is now dead) and there is a bit of a panic on about it in Berlin, and at Pullach, since it was an Act of War on Great Britain by West Germany.

Realising they had been blown up wasn't difficult :

(1) only Comets flying out of one airport suffered metal fatigue (huh?)

(2) this airport had lousy security, in the charge of a bunch of ex-fascit left-overs from the Mussolini era

(3) the first Comet, flying north, blew up over water thought to be too deep for recovery.

(4) when new technology permitted substantial recovery, despite interference from the Italian Navy, the next Comet was blown up going south, over water 3,000' deep. Mighty odd co-incidence that.

(5) only British Comets suffered metal fatigue (the SAA pane was leased from BOAC).

(6) there wasn't a crack on the whole fleet

(7) wings would have gone first - greater stress, same skin thickness - and did go first on Yoke Uncle

(8) RAE couldn't replicate the fatigue failures at 2,750 hours, or anywhere near it

(9) RAE report is dodgy, hours don't add up - turns out YU was in the tank for the quivalent of about 24,000 hours.

(10) an RAE scientist involved in the report was offered a colossal sum of money (1.5 m DM) by the standards of the day to rig the report, he left RAE shortly after it was published

(11) the DH water tank test fuselage section was tested to 40,000 cycles, at a big overpressure

(12) we now know Farnborough cranked the pressure up to get a break earlier - they were actually frustrated by how long YU was lasting! The RAE report is worthless.

(13) we now know the French allowed Hertzog access to their Comets at Beirut, to help plan thr attacks.

(14) we also now know the Germans paid for the Air France Comets, I think thru Banque du Liban.

(15) the Italians rigged the YP autopsies, which is why the Navy was ordered to shoot up the Italian navy if need be to keep them away from any bodies found from YY, things got pretty tense off Stromboli, the Italians saw a big task group coming and stayed away.

(16) HMS Eagle only used her Avenger AEWs in the search, and they were only looking for bodies, seems the rest of her air group wa sheld back in readiness for attacks on the Italian Navy if need be, with the hope that a show of force would be sufficient. Many of the passengers on YP were kids going back to school, DH, BOAC, MCA & Intelligence were livid with the Italians for letting the bombs on, but we didn't have the details on Hertzog.

(17) The Americans got the blame and Anglo-American relations went quite cool for a while, DH however knew Boeing not involved, major figures inckuding George Edwards knew it was sabotage, knew the government knew and knew that DH were offered a deal they couldn't refuse to keep quiet.

(18) So far as I can tell the first Caravelle front sections were unmodified Comet 1!! The production Caravelle front fuselage and Comet 4 weren't that different, although they had a thicker skin. DH knew there wasn't really a problem, except the window radii were too tight and might have failed around 24,000 hours (as did YU, albeit only at an overpressure), although there was never any prospect of a Comet 1 going above 15,000 hours, and most were only expected to do about 10,000 hours, if that. They actually had a big margin of safety, particularly at 36,000'. They were designed for FL400, but rarely went above 360. There was a careful program of wing inspection, as the type was so radical, and any cracking would have shown up on inspection long before it got critical.

Michael Shrimpton

This information is quite interesting, but until it is published we should leave it out of the article. Otherwise anyone could come in claiming to have a book ready to publish and change the article to what they want to see. Also, even when you do publish, it probably wouldn't be a good idea to put this info in the article yourself, otherwise some accusations may get tossed around.--LWF 01:58, 5 February 2007 (UTC)

Some accusations? The above -- as well as all the implications in the article already -- reads like an X-Files episode. Without citations of reliable sources, NONE of this is remotely appropriate for the article.--chris.lawson 02:25, 6 February 2007 (UTC)

I would agree that the above theory should be mentioned, but a large part of the article is now taken up by this point which sould be a one-liner under trivia!. The statement about the Carvelle doesnt ring true as far as I know only the comet cockpit section was used on the caravelle, a lot smaller than the "forward fuselage". Only British comets suffered - probably because they were more of them - Air France only had three. The point about Boeing not making any money on the 707 is also doubtful as the program was underwritten by the KC-135 tanker program. I could go on. But I would suggest that the theory should be reduced to one line unless plausible citations can be given. I would support User:Bzuk statement below. MilborneOne 22:33, 11 February 2007 (UTC)

As I have noted above, the ADF windows from the Elba aircraft still survive. I am sure that even at this distance, any evidence of explosions would still be evident.... Brucewgordon 17:03, 14 February 2007 (UTC)

References needed

In order for the de Havilland Comet article to be treated as a serious piece of research, there has to be some check on the constant reversions and revisions that have occurred in the recent history of the article. There are many reputable sources of information available and editors should qualify their commentary with appropriate references, otherwise the work comes off as a flawed, less than neutral observation. I can appreciate that the Comet represents an iconic aviation programme that has been the subject of ongoing interest, however, scholarly, balanced research should be the watchword. Bzuk 22:23 11 February 2007 (UTC).

This article should be considered as seriously flawed with some of the recent additions to it. Sadly, the de Havilland Comet has become the target for a number of spurious conspiracy theories, which have been included in the current revision. There are plenty of good accurate sources for information on the aircraft, including numerous books, de Havilland Gazette articles published by the company, and the original RAE report which is available online. I have yet to see any evidence that disproves this. In my opinion, the entire article requires re-writing. Brucewgordon 16:31, 14 February 2007 (UTC)

In reviewing the latest submissions to the de Havilland Comet article, other editors may wish to address areas of uncited or unproven theories that are being proposed. As earlier editors have noted, the introduction of controversial elements of research should be brought out in discussion pages first and not in wholesale entries into the original article. If there is a series of entries that can be fully documented, the truly historic and influential aircraft project that the Comet represents, will receive its proper recognition. Bzuk 17:23 15 February 2007 (UTC).

Entire accident section should be removed

I have been drawn into this article through a roundabout series of jumps from my watchlist. I can't believe the state of this article. The history of this incredibly important aircraft is far far too short, the technical description was rambling, and the accident section is far too long, rambling and filled with the personal musings in an extended conspiracy theory. The author in question has not responded to any of these charges, and has instead involved himself in an edit war with Bill in which he made several insulting personal attacks.

This entire section needs to be either removed, or heavily edited. Immediately.

And once that's done, someone really has to write a history for this aircraft. I find it somewhat sad that the Trident has a much longer and more detailed history than the Comet. Don't get me wrong, the Trident is a fine aircraft, but the Comet is the first and thus very important historically. I can do this, but it won't be until the weekend, if not later.

Maury 13:18, 16 February 2007 (UTC)

Glad you did it. I was "stunned" and about to do something similar. Gwen Gale 14:07, 16 February 2007 (UTC)

There's definitely something very wrong with the sections regarding the accidents; it dismisses the "official version" out of hand and then waffles on about all kinds of unsourced conspiracy theories ("There is also said to be", "Some may think it curious", "It is believed in some quarters that". "believed by some within the intelligence community"? I mean come on...). I'm reducing the class assessment to "Start" until this is addressed. FiggyBee 06:32, 17 February 2007 (UTC)

Ok, I've taken a stab at it. Some comments:

1) There is no indication that the Canadian pilots were "inexperienced" as the article stated. Reading between the lines, it appears the Comet had a real flaw with the wing design, likely spanwise flow due to the swept wing -- a common problem that caused a series of aircraft design throughout the 1950s and was so common on one design it became known as the "Sabre Dance". I can't help but feel that the editor in question is attempting to whitewash the aircraft as being the problem. BTW, this problem with the Comet was actually commented on in my commercial pilot course, along with other early-jet problems like the extended takeoff runs on the Me 262 (very similar in fact) and the "coffin corner".

2) The article then spent no small amount of time talking about fatigue of the wing root, just before going on to state that no fatigue was found at the wing root. I could understand mentioning this if it was a major area of investigation during the post-crash research, but I couldn't find any statement to that effect. I simply removed it all.

3) Any comment that required knowledge the editor could not possibly know was removed outright. This included speculations about what Lord Cohen did or did not fail to think about, unpublished comments by BAC, an unstated "some" that appears to refer to the editor himself, top secret reports that may or may not exist, references to shady characters known only by nom de plume.

4) Other speculations, like the Caravelle being the "same" are likewise removed.

Maury 14:43, 17 February 2007 (UTC)

I've removed another paragraph, which had no sources and seemed to be begging some kind of conspiracy theory (who says the missing centre sections were "critical"? Who was preventing the RAE conducting "independent autopsy" on supposedly burnt bodies?). FiggyBee 17:06, 17 February 2007 (UTC)

I should also take the time to explain to Michael what's happened here, and why. The wiki has strict rules about what is and is not suitable material for inclusion. It basically comes down to "third-hand information only". That means that original data should not normally be presented, nor should second-hand information. The wiki is expected to be an overview of the generally accepted state of the art. Your material, while interesting, is new. Not wrong, not unwanted, just new. And new data is not supposed to be here. You are not the first person who's joined the wiki to find their contributions being reverted by people who they don't believe are experts, but it's very important you understand that its not being removed because we disagree with the material, but because the material simply doesn't belong here. All too often when someone has their edits reverted they believe it is because of the other editors are unfamiliar with the content, not understanding the sometimes labyrinthine rules over the content itself. Invariably this ends up on Slashdot as a complaint about the wiki rejecting experts. *sigh* I welcome you to write all of this, including material from this page as long as it's mentioned somewhere, on your own web site. It seems to be looking for some content, so this seems appropriate. Maury 19:27, 17 February 2007 (UTC)

You know who (as in Harry Potter speak, the one we shall not speak of) is at it again. Sigh... Bzuk 20:35 17 February 2007 (UTC).

The standard is more or less a citation from a reliable published secondary source (that would be "third hand"). Anything else can be removed outright if such a reference is requested an none is provided. Gwen Gale 00:28, 18 February 2007 (UTC)

More stuff removed

I explained all of my edits in more depth that I thought they deserved, but here's all the same stuff back again, without a single comment on the talk page. Way to go Michael!

1) The testing of overpressure on the window clearly has no bearing on whether or not the window frame would fail. Yet this is precisely the claim you make in the article. I have removed this misleading claim for obvious reasons.

2) I'm still not exactly sure what your point is about the wing sections, but whatever it is, it's not obvious. It is true that the wings were discovered to suffer fatigue problems during the Abell Committee, but that doesn't change anything that I can see. It's just one more reason to the believe the aircraft failed for fatigue reasons.

4) You claim that the wing failed on G-ALYU, but the wing was not included in the test, something you even mention. You also claim that the RAE's report should be ignored for this reason, but in fact the RAE report mentioned that the wings were quite susceptible to fatigue, and this was mentioned in the report.

5) The French Comets did not suffer from fatigue because they were removed from service. One was re-skinned. Far from suggesting fatigue was not the problem, it suggests it was.

6) (generally unrelated) it is a well known fact that podded engines are in fact far more aerodynamically useful than embedded ones. That's because the pylons act as "free" wing fences, and thereby stop the spanwise flow that I'm assuming is the cause for the problems during overrotation (which is otherwise a non-problem). They also make the engines harder to service, which I'm guessing has something to do with the poor serviceability of the Comet (5 hours per 1? Geez, I thought our 30 year old 185 was bad...).

Let's be clear:

Both "mysterious" losses failed at about the same number of flight hours, and the recovered and re-constructed airframe obviously failed from metal fatigue. The damage clearly shows "ripping" along the rivet lines along the body panels and between the windows. I've seen these reconstructions of bombed aircraft, and bomb damage is painfully obvious, if it exists. It did not in this case.

The test airframe failed from metal fatigue at about 3000 flight cycles, and failed in a manner essentially identical to the damage seen on YY. The official report notes that it failed at 10.4 psi, about 8000 ft effective. These facts are both the opposite of what you claim. Actually, pretty much every claim you make is directly contradicted in the official report.

Modifications were carried out given this result, and no Comets disappeared mysteriously again.

For those that care, the official report can be read here [1]

Maury 01:23, 18 February 2007 (UTC)

Rewrite

Now that these needed revisions have been carried out, I've rewritten the whole article for flow and narrative. With no content removed it's about a third shorter. Gwen Gale 08:01, 18 February 2007 (UTC)

Thanks for the rewrite Gwen Gale, I had started last night tweaking a bit of the history, but couldnt face the technical data. Article is looking a lot better and more balanced. MilborneOne 09:15, 18 February 2007 (UTC)

'Twas a slog, but it reads like an article about an airplane now :) Gwen Gale 09:22, 18 February 2007 (UTC)

Nice work Gwen and Maury. The Comet can have its B back. ^-^ FiggyBee 14:12, 18 February 2007 (UTC)

Sabotage of Comets Yoke Yoke and Yoke Peter

I was new to Wikipedia, having been referred to the Comet site by an executive at Lockheed Martin. It was in a terrible state, full of inaccuracies, and a silly conspiracy theory about de Havilland chosing their own engines (which were the only ones available) and deliberately putting an unsafe plane in the air with too thin a skin.

This theory has no place in Wikipedia, nor should the article make a controversial assertion about the hotly disputed causes of an airline disaster, although of course the deeply flawed RAE report should be referred to. Milborne 1 with respect seems to think that Wikipedia should recite the findings of the RAE report as though they were uncontested and accurate - that seems to me to be rewriting Wikipedia's rules, or failing to apply them because he or she does not like the alternative, which is that the aircraft were destroyed by an IED, which indeed they were.

The article should be neutral, balanced, and sourced, and that is what I aiming for. I have added an additional source today and there are more to come, in particular the major text on the Comet airliners, by Martin Painter. To assert as fact a particular cause for an airline disaster on Wikiepdia, as Milborne 1 wants to do in respect of Comet Yoke Yoke, before the wreckage has even been examined, has nothing to do with neutrality. Please also note that Lord Cohen conducted his inquiry unlawfully, in breach of the rules of natural justice, in that he deprived de Havilland's counsel (Sir Hartley Shawcross QC, Roger Winn as he then was and H A P Fisher) of the oppprtunity to cross-examine the report's authors. The report was bounced on DH at the end of the inquiry. Given Lord Cohen's unfairness towards de Havilland, and the vitiation in law of his conclusions as a result (breach of the audi alteram partem rule renders his report a nullity) the last thing Wikipedia should be doing is giving it credibility. The report is in fact largely rubbish, and the assessors (Sir William Farren CB FRAeS, Professor W J Duncan CBE FRAes and Air Commodore A H Wheeler), who unlike Cohen knew one end of an airplane from another, were careful to distance themselves from Cohen's intemperate and ill-informed attack on the de Havilland company.

To illustrate what rubbish this report is, and how unworthy of serious treatment on Wikipedia, one only has to look at its feeble explanation for the major discrepancy between the tests on Yoke Uncle and the lost aircraft, which included "structural differences." Yoke Uncle was an unmodified BOAC Comet 1 pulled off the line. No wonder Cohen would not let a barrister anywhere near the RAE report - experienced counsel would have torn the authors to shreds in the witness box, given that level of asinine stupidity.

If de Havilland's legal team had been made aware of the offer of 1,500,000 DM to one of the report's authors by a bank in New York, linked to the Nazi money-launderer Jean Monnet, who was on the DVD payroll in 1954-5, counsel might well have asked for one or more members of the RAE team to be arrested.

Certainly the police should have been called in, and the RAE team interrogated by Special Branch, except for Arnold Hall, who was simply an ambitious government scientist on the make, and not too particular about who he trod on on his way up the greasy bureaucratic pole, there is no evidence he took cash from the Germans, he was simply not bright enough to spot what was going on under his nose (he didn't even have some-one check the pressures, Yoke Uncle was supervised by one man at times, at night, it is very probable the pressures on Yoke Uncle were yanked way up beyond 10 psi, given the 16,000 cycle test DH did, ie the RAE methodology was a fatally flawed.)

I was careful to underplay the criminal aspects of the RAE investigation in the article, although I agree some of the references to intelligence reports should have have been removed, given what I am told about Wikipedia's rules. (forget your snide, and offensive, X-files references, Bill Colby was a friend of a friend who flew U-2s and A-12s for the CIA, there was a CIA report, and it blamed the disasters on IEDs, the DVD's Hertzog is I believe named in the CIA report, but it's still classified, the DVD is not referred to by name, although Bill Colby was smart, and knew there was a shadowy German intelligence organisation operating in Rome in 1954, Mossad knew about the DVD, by name, indeed I have discussed the DVD with Mossad officers, any major player in Israel who reads this might like to talk to a guy named Rafi Eitan, who did that great snatch job on Adolf Eichmann, Eichmann was DVD Head of Station Buenos Aires and very active post-war, he was close to von Lahosuen, DVD Deputy Director, and probably in the loop on the decision to attack the Comets, but he was not in Rome in January or April 1954).

Unlike BZuk, with respect, I am only interested in fact (this I assume is the same BZuk who cannot distinguish between pre-production and operational aircraft and thinks the Me262 was the world's first operational jet fighter, although it only entered operational service in October 1944, more than two months after the Meteor). I go where the facts go, and unlike some on this page, I am not frightened if they lead to me a conclusion that an airplane was sabotaged, even if that requires more intellectual effort than tamely accepting a government whitewash.

I note that no one has seriously tried to get to grips with the detailed points I make above. Yes, there were signs of burning on the bodies, put down to post-mortem sunburn, utterly ludicrous, not least because there was 8/8 cloud, but post-mortem sunburn is a tricky area anyway - dead bodies can burn just from sunlight, but live bodies burn quicker.

No the center section was not recovered. Look at Darling, p 71, where there is a breakdown of what RAE were able to look at, there's a big chunk if the plane missing in the center-section area, right near the lower cargo hold, which is where the IED was placed.

Rome had lousy security, run mostly by 'ex'-fascists, Hertzog was given overalls and got close to the plane, pretending to be part of the refuelling team, they needed to get under the wing, very easy to get the IED onboard.

Don't forget Chester Wilmot was on the flight, he was a bonus for the Germans, they were upset by his fair war-time reporting and had a score to settle. The school children on Yoke Peter were another added bonus for the DVD, as they made the disaster more shocking, and ensured newsreel piccies of weeping parents, a similar tactic to the U-Boat attack on the RMS Athenia on September 3rd 1939 (pro-Germans in the government had made sure she sailed with lots of kiddies to Canada, the idea was to tell the Abwehr the course, drown the kiddies and try and shcok the British into not going to war, it backfired on the Germans, I daresay some of the lads on the Exeter remembered the murdered children of the Athenia a they rammed the 8" shells home to smack the Graf Spee).

Yes Air France had 3 Comets, F-BGNX, F-BGNY & F-BGNZ. The airline was thick with Vichyists, and they co-operated fully with the Germans, in fact that's why they bought the planes. They ran them on a bogus schedule to Beirut, where they were hangared, DVD Beirut Station (still pretty big, liaises with Hezbollah) were given access to the planes, which allowed them to work out the amount of explosive they required.

Interestingly the DVD's man at Farnborough (yes, one of the authors was working for them, as he had worked for the Nazis before and during the war, Hall thought he had been 'de-Nazified') under-estimated the strength of the new alloys DH selected for the Comet. They underdid the plastic on Yoke Peter, and also got the recovery depths wrong (they didn't know about the underwater telly), nearly getting themselves caught (just as well for them the Minister of Civil Aviation, the notorious appeaser and protege of Neville Chamberlain, Lennox Boyd, was on hand to help with the cover-up, he reported to Admiral Canaris thru World War Two, the Germans also had an asset in the Lord Chancellor's Department, to help with the selection of the judge, (he later became Permanent Secretary, and promoted pro-German judges, or judges who had been compromised in the DVD/GO2's honey-trap operations - one their people (GO2) was Stephen Ward - who were prepared to defy Parliament and insist on supremacy of European Community law, he also elbowed out Lord Devlin, who was concerned about the constitutional aspects of the Treaty of Rome).

The DVD upped the explosive for Yoke Yoke, and made sure they bombed a plane going South, so she would blow up over deep water.

They used barometric fuses, set for 3,000 meters, with chemical timers, technology the Abwehr had developed in World War Two. The chem fuses could be set for 20-40 minutes, but were a bit tricky. Rome was a good choice to blow the Comets up from, as the approach and departure was largely over water. The fuses were basically a plus or minus 5 minute affair. They were set for the same time for both YY and YP.

Yes there was spanwise flow, and it was picked up late, but the Canadian Pacific crew had absolutely minimal time on jets, less than 10 hours as I recall, (look it up), sadly they killed themselves trying to take-off DC-6B style. Had they not yanked the stick up they would have got off alright. In contrast, the RCAF boys really knew how to fly Comets and chucked them round the sky. All civil operators of the Comet 1 were slow to get to grips with the jet age, and the planes undoubtedtly suffered at the hands of piston-engined pilots who kept trying to fly them like a DC or a Connie, shut the radiator flaps etc etc. Remember the only operational jets in North America in 53 were military. These guys were on their first extended trip in a jet plane. It's no wonder they didn't make it, sadly. Of course it wasn't just the pilots' fault - the lack of a wing fence was a contributory factor, and whoever dreamt up the crazy schedule played a big part.

Finally, just to show how fraudulent the Farnborough report was, the famous window failure (there was an earlier failure at 3,057 cycles, this is the '9,000' hr failure, actually 8,740 hours, a massive 6,000 hours above Yoke Yoke's airframe time of 2,704 hours, and it was at the escape hatch, at 10.4 psi, nowhere near the Yoke Peter break-up, which occurred at approx 5 psi) allegedly occurred at 13,850 hours, 11,146 hours (try 6.5 years of airline service, say October 1960, way beyond the airplane's expected service life). BUT, (Painter, p. 103) the Yoke Uncle tank test started on May 19th 1954 and the window (pof course I am referring to the frame) crack did not occur until 36 days later (June 24). That is a whopping 15,552 equivalent hours, plus the 3,539 hours YU already had on the airframe, which takes us to over 19,000 hours, subject to the amount of time (not long surely) needed to repair the escape hatch damage, the RAE seem to have cooked the books and deducted an extra 1750 hours or so. Unlike some of the people who have been vandalising this site ovr the weekend to push the metal fatigue theory I can count!

We need to know whether these hours were deducted before or after the "8,740" hour failure - probably before, because there is the 'spread argument' (a fatigue failure at 9,000 hours could mean a failure at either 3,000, on a 3:1 ratio, but the argument is intellectually dishonest - the spread could be up or down, ie the true range could be 9,000 to 27,000, please bear in mind Uncle already had 800 more hours on her than Yoke when she went down before she even started the test).

And this takes no account of the overpressures - RAE lied to a judicial inquiry (they may well have suspected Cohen was tame before they took the risk, at any rate no one was allowed to cross-examine them) and if they did that, just what pressures were they loading onto YU? no one actually knows, although we do know the pressure she failed at was a whopping 2.9 psi overpressure compared to service ceiling and about 5.4 psi above the actual pressure at the loss of hull inegrity. I make that about 52,000' equivalent. All these pressures are cabin pressures - 8.25 psi at 40,000', 7.5 psi approx at the service ceilig of 36,000.' The cabin pressure ws set to 10,000.'

So, RAE got a Comet 1 to fail at about twice the altitude it actually failed at, at about 7 times the service life of the second plane which went down, in a different place to where the first plane 'started' to break up (about exactly where we would expect upper fuselage breakup to start for a powerful IED in the lower cargo hold - of course it's all nonsense, because the plane started to break up near the IED, a part of the plane the RAE unsurprisingly never saw), only it was a lot more than 7, because RAE were loading the pressures, especially at night. Big deal.

All the RAE report tells us, apart from the fact that the report was a fraud on the public and Lord Cohen (but since he kept barristers away from it he might not have been fooled the same way BZuk and the media were!) is that the Comet 1 should not have been flown for more than 10 years at over 50,000 ft. Since the 1 was an interim type, whose successor was already flying before 1954, not expected to stay in service beyond say 1955, and didn't go much above 35,000 feet in airline service, and couldn't go with a payload beyond 40,000, it follows as night follows days that de Havilland got their number right.

Since they were about the most experienced builder of aircraft in the world at the time and had built the most versatile plane of WW2 (the immortal Mosquito), this was as we would expect. Oh and by the way, the Germans have admitted blowing up the Comets (we went to them with my research and it was 'hande hoche' time, it was they who gave us the name of their agent who blew up both planes, Hertzog, they knew we knew and we were trying to mitigate the diplomatic fall-out.) They blamed Konrad Adenauer, who gave the all-clear to von Lahousen to destroy the Comets.

Subject/headline: —The preceding unsigned comment was added by Michael Shrimpton (talk • contribs) 14:31, 18 February 2007 (UTC).

Michael,

Until you can provide some evidence that the causes of the YP and YY crashes are "hotly disputed" by anyone but yourself, it is original research and has no place in Wikipedia. I would be interested to read your theories about what happened to the Comets - if only to pick holes in them - but not here. FiggyBee 15:29, 18 February 2007 (UTC)