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Post by almguy1 on Jul 9, 2011 9:15:52 GMT
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Post by Klaus Hullermann on Jul 9, 2011 9:56:25 GMT
Nice and smokey formation of three comets (looks like a Comet 4C, right?).
Klaus
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Post by Herman on Jul 10, 2011 0:34:48 GMT
Great pictures, great airmanship.
Now let me know how you accomplished this.
Herman
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Post by almguy1 on Jul 10, 2011 16:10:26 GMT
Great pictures, great airmanship. Now let me know how you accomplished this. Herman Thanks Herman, A little tweaking using FS RECORDER still not easy though you have to fly the flight a few times times and get the timing right. and switching aircraft. its time consuming. |
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Post by almguy1 on Jul 10, 2011 16:15:04 GMT
Nice and smokey formation of three comets (looks like a Comet 4C, right?). Klaus Yes good old Comet 4C Klaus,... those extra wing tanks made the comet a more sexy sleek, aircraft it looked kinda clunky in the first models. Dave |
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Post by almguy1 on Jul 10, 2011 16:23:18 GMT
If they had made a more attractive vertical stabilizer as well it might have helped its image Also the entry door forces passengers to bend down to enter. I have bumped my head a few times on the Mexicana comet door frame ,forgetting how low it was. also the floor was not flush with the door frame its a step under and step over as I can recall.
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Post by aerofoto - HJG Admin on Jul 11, 2011 1:19:12 GMT
The thing that really buggered up the COMET was those 2 major accidents of 1954 .... resulting in explosive decompression of 2 BOAC COMET 1 airframes. There were other accidents before this though which were both design and handling related .... The COMET 1 was known to require very precise/delicate handling at rotation, in particular, due to "airflow" issues and the size of it's engine intakes as well as the design/shape of its wing leading edge .... which resulted in a number of accidents occurring when aircraft attempted to get airborne (albeit unknown to their crews) in a semi-stalled condition .... as occurred with at least 2 BOAC aircraft at Rome, as well as the CPA aircraft (on it's delivery flight) at Karachi (I think it was) .... and there were other incidents too. That was the limit of technology back then .... and we've all learned and progressed from there. Some of the industry was also skeptical about the introduction of jet equipment at the time of the COMET 1's entry to service .... though this had nothing at all to do with doubts about the types structural integrity. That all happened later. The industry was, then, still learning a lot about flying jets .... hence the number of accidents prior to the 3 major BOAC disasters (one aircraft disintegrated in midair somewhere over India too on the 1st anniversary of COMET operations) that occurred and which eventually made some airlines dubious about the type .... but .... it was essentially those 2 major accidents, of 1954, which resulted in the COMET's CoA being withdrawn that really scared the industry and did almost irreparable harm to the entire project. Even after the cause of the 1954 accidents had been diagnosed .... there were still some whom thought the entire COMET project (which was already up to designing COMET 3 by this time) should be abandoned completely. By the time a firm decision was made by DH to advance the COMET project .... its development team had lost so much time, and with some of the industry was still dubious about the type, and with both the B707 and DC8 having already flown too .... or being about to fly .... the COMET simply couldn't compete (economically) though it did actually do so for a few years on some of thev worlds most prestigious air routes. Had the cause of the COMET disasters been diagnosed more quickly .... or better still hadn't occurred at all .... then the types success would have been far greater than what it actually became .... as evidenced by all of the COMET 1, 3, and 3 orders which were eventually lost due to the 2 major accidents. Garry might be able to elaborate more on this !  Mark C AKL/NZ |
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Post by almguy1 on Jul 11, 2011 2:30:36 GMT
Hi Mark Thanks for your input some I did not know,I am familiar with most of the early Comet history as a matter of fact I saw Couple pieces of that first one that disin over the Med at the Science Museum last year in London that were salvaged from the sea bed. forgot if it was first or second but I did take a photo. Im referring to the 4C model not sure if they ironed all the bugs out but somewhat, I was just throwing in my 2cents worth even though they maybe outdated currency  . Guess they would have a parts problem anyway with limited sales but were overwhemed by B707 having more capability and US airlines buying those instead. Well Im repeating what you already said so as a famous NZ WW2 pilot once said "I'll quietly bow out now" Dave |
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Post by aerofoto - HJG Admin on Jul 11, 2011 3:37:40 GMT
The COMET 2 (modified), and the COMET 3, 4, 4B, and 4C were all good aircraft .... once the reason why the COMET 1 failed was understood.
It's just that it wasn't understood prior to the COMET disdaters of 1954.
What happened to the COMET 1 .... and to DH AIRCRAFT COMPANY in particular .... is sometimes the high price paid when one trailblazes in respect of new technology. One is then the first to reap all of the benefits .... but then .... one is also first to discover (sometimes disaterously) all of the problems too.
The COMET 1 structural failures were actually caused a combination of factors .... ranging from the types square-ish window appetures to start with, to the then new super light-weight alloys used to skin the aircrafts fuselage, along with rows of rivets which were placed too closely together near where the origins of the failure/s occurred .... as I understand things.
The courts ruled that nobody could be held culpable for the COMET 1 disasters .... because of the pioneering nature of the project and the fact that all due care, by the standard of the time, had been takenh by DH designers.
The COMET disasters weren't in vain though .... despite the high cost of inocent life .... because they pathed the way towards the the better/safer aviation industry that we know and benefit from and mostly take for grantid today.
Hopefully not too much for grantid though
Mark C
AKL/NZ
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Post by walterleo on Jul 11, 2011 12:22:47 GMT
...Also the entry door forces passengers to bend down to enter. I have bumped my head a few times on the Mexicana comet door frame ,forgetting how low it was. also the floor was not flush with the door frame its a step under and step over as I can recall. Hi But you where happy to fly in one of these birds, I only saw one of them parked at Mexico City's Airport in 1972, and later taking off from LOWS (what a racket!) But praise to the pilots of MEXICANA, who did no harm to any of their Comets 4 C, which was a pilots airplane, which means it was not at all easy to handle. Various training accidents with other airlines (like Aerolineas Argentinas) demonstrated that fact. Besides the wings problems at take offs (which later was corrected) there was still the necessity to change the powered controls after rotation from coarse to fine, if not over-controlling the elevator was guaranteed. But besides that the T.O. and landing speeds were much lower than for 707 and DC8 (not to speak of CV 880,990) which made it ideal for hot and high airports like MMMX. And the 4 C was quite overbuilt, so its structure flew on till the end of last month as the submarine hunter NIMROD. Kind regards Walter |
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Post by garryrussell on Jul 11, 2011 13:07:11 GMT
Nice formation...pity it's not three different aircraft  The takeoff problem was helped by redesigning the wing LE. The structural failure was it seems DH induced and kept fairly quiet. It is said that the didn't appreciate the implications of pressure cycling, but they did, the reason the Viscount and Britannia had elliptical windows and the Comet had a fuse tested. This was all before the crashes. In fact so concerned were Vickers about the possibility the had elliptical doors on early Viscounts. On production instead of the bonding as designed they found it easier to punch the rivets into the window cut outs causing a small imperfection that lead to cracking far earlier than the design life. They might have got away with it but the miscalculated the stress concentration on the cut out corners. The later Comets although good, shared, along with the Viscount and Britannia, construction using an alloy that was prone to corrosion. This reason saw some Viscounts and Comets retired for scrapped at less than ten years of age. In my opinion though, the biggest problem with the Comet was it was ugly  Garry |
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Post by walterleo on Jul 11, 2011 14:41:35 GMT
In my opinion though, the biggest problem with the Comet was it was ugly Garry Hi "ugly is relative and a question of taste. The main problem was the redesign and therefore lost time after the structural failures of Comet I, the too Small cabin and the endurance not ideal for the Atlantic. Sometimes life punishes also those who come too early. And the British Aircraft Industry had always the problem, they had to ask their airlines first, BA, BEA, BOAC defined an airplane mostly too small for the future traffic and after-wards bought the US product, because it was more adapt to the "market". So wonderful pieces of technology with fancy advancements (first "blind-landing" etc.) went the the museums. Regarding to corrosion. At least the crash of the Vanguard (Super-Viscount) on the London-Salzburg flight was more a design flaw than the alloy: Seems nobody thought to put a drain-hole at the lowest point of the structure IN FLIGHT, not while at the apron. In that way water from the toilet destroyed the aft pressure-bulkhead and near Bruxelles's cruising at 18.000 feet the bulkhead together with the stabilizer parted from the plane. All aboard died, some friends of mine among them. www.aaib.gov.uk/sites/aaib/publications/formal_reports/15_1972_g_apec.cfmWalter |
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Post by garryrussell on Jul 11, 2011 16:04:38 GMT
Ah yes..beauty in the eye of the beholder I find the Comet 1 the ugliest of the lot...it's that nose that I don't like and the same reason I never cared for Caravelles either.  The Vanguard structually was nothing like a Viscount and used diffent materials pre treated during contruction, so I'm not sure where the comparison of the BEA crash and the materials used in Viscounts comes from  I don't know that the corrosion caused many accidents as such in the Viscount, it just made them un economic to keep corrosion free. EAA Comets were very short lived ( seven years or so) and the Viscount 812's bought by Channel Airways were being withdrawn as early as 1967 due to advanced corrosion and they were all built from 1958 onwards. |
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Post by aerofoto - HJG Admin on Jul 11, 2011 20:44:26 GMT
Lesser known facts about the COMET and the US operators ....
PAN AMERICAN WORLD AIRWAYS did order the type (the larger COMET 3 during 1952, but, that order was one of many lost after the 1954 COMET 1 disasters, the grounding and suspension of the types CoA and production, and essentially the types then "uncertain" future by this stage. Commentators have also speculated that the PAN AMERICAN order was simply a ploy, by Juan TRIPPE .... who was apparently always very good at playing "POLITICS" .... to motivate the US producers into committing to the production of a jetliner as the future of jet airliners was, during the early 1950's, still far from being a sure bet.
1 US airline .... CAPITAL AIRLINES .... did in fact commit to the COMET, after the type, now modified, went back into production. CAPITAL already operated a large fleet of VISCOUNT turboprops and ordered a new version of the COMET .... then designated COMET 4A. CAPITAL merged with UNITED AIR LINES during the early 1960's, and this order was promptly canceled. The COMET 4A never flew ..... but .... went on to become the -4B which eventually entered service with BRITISH EUROPEAN AIRWAYS.
Mark C
AKL/NZ
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Post by walterleo on Jul 13, 2011 9:05:13 GMT
Lesser known facts about the COMET and the US operators .... PAN AMERICAN WORLD AIRWAYS did order the type Mark C AKL/NZ And PANAM was parent of MEXICANA, when they ordered the Comet IV C. There were rumors, that Trippe was eager to see, how the Comet IV was in comparison to the B 707. (Always have a plan B!)  The IV C flew quite a long time on with DAN-Air as charter airplane. Think one or two of Mexicanas ones were flying with DAN-Air. Kind regrades Walter |
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