De Haviland Comet variants?

Question

How come de Haviland built different variants of the Comet?

Apologies, don't really know anything about aircraft.

Was each variant to replace the previous one due to crashes?

Answer 1

There were a number of variants, square windows, changed to rounded, power plant changes etc, culminating in BAe overhauling the design with the Nimrod. The Nim has been used for two roles in the RAF, maritime and airborne intelligence (51 Sqn). The latest variant has a combination of the two, capable of maritime and aerial intell work. Although the Nim has been operated since the early 70's, the airframe does not lend itself easily to major changes such as the AEWA (the big nose and ar*e version!) variant which was superb when working (in fact better than the AEW currently used), but had serious overheating problems and very little space on board.

A superb ground breaking aircraft in its day, being the first jet airliner and work-horse of companies such as DanAir, now working well into its retirement period.

Answer 2

Yes -you're correct in your assumptions. The later marks of Comet had altered window design - the crashes were found to be caused by catastrophic depressurisation due to metal fatigue at the corners of the windows. They were redesigned with round windows instead and the later models also had more powerful engines. Of course the RAF are still flying variants as refuelling tankers and for submarine radar .

Answer 3

After the crashes that occured with the Comet 1 the aircraft was redisigned and was reintroduced as the Comet 2.  

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The Comet 3 was a lengthened Comet 2 with greater capacity and range. After the fatigue accidents, orders dwindled and only two Comet 3s were built. One flew and the other was used for structural and technology testing during development of the similarly sized Comet 4. Nine further airframes were not completed and their construction was abandoned at Hatfield.

Comet 4



Comet 4C showing the engines built into the wing, and the safer round windows of these later modelsThe Comet 4 was a further improvement on the stretched Comet 3 with even greater fuel capacity

It was somewhat sucessful but was totally eclipsed by the much larger American jets.  Military varients of the original planeform were built the Nimrod is one and I believe tanker versions.  The nose cone and front end and forward cockpit windows design was used for the twin engine Sud Aviation Caravelle as can be seen in these two pictures.

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http://www.airliners.net/photo/Dan-Air-L...

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http://www.airliners.net/photo/Finnair/S...

Answer 4

the early comet ( Comet 1) suffered catastrophic failure of the fuselage. it  was a new phenomena called metal fatigue. She had square corners to the windows, just like the old Dakota one, and these acted as stress risers and when the fuselage had been pressurised a few times she popped. The loss of lfe in the crashes was effectively the death of our transatlantic jet sales, and the comet went from golden balls to goat. The Yanks however with their 707 ordered straight off the f*g packet by the USAF never looked back. Not that there was any cross subsidy, heaven forbid, the Air Force just happened to buy enough ( several hundred) to let Boeing sell them cheaply

once the fuselage had been redesigned she went on to be Comet two and four if memory serves, she then become the Nimrod, still in service after 30 odd years, so its not been a bad ship. .

The Comet was used by the RAF as the Comet two and then the Four, then the various Nimrods. some of those wings are older than the combined ages of the crews

Answer 5

main variant was the Nimrod.

Answer 6

As far as I know one of the last variants was the Comet 4c, I flew on one some where around 1978/9 to Corfu, it was owned by "Dan Air" airways who bought it from the RAF who had used it as an executive jet, I ask to go onto the flight deck and was given a "tour" by the captain in mid flight to Corfu, he told me it was soon to be taken out of service due to very high running costs (4 tons of fuel an hour).

Here is a brief history.

The Comet was built at two different de Havilland factories: Hatfield and Hawarden. A total of 114 aircraft were completed and flown: 12 Comet 1s, ten Comet 1As, 15 Comet 2s, one Comet 3, 74 Comet 4, and two HS.801s.

Thirteen aircraft were lost in fatal accidents and of these, five were considered to have been brought about by aircraft design or fatigue problems. The last fatal accident involving the Comet was at Tripoli, Libya on 2 January 1971, caused by pilot error.

A total of 76 Comet 4 family aircraft were delivered from 1958 to 1964. BOAC retired its Comet 4s from revenue service in 1965 but other operators continued flying Comets in commercial passenger service until 1981. Dan-Air played a significant role in the fleet's later history and at one time owned all 49 remaining airworthy civil Comets. In 1997, a Comet 4C which had been owned by the British government made the last documented Comet flight.

Although the Comet was the first jet airliner in scheduled passenger service, the damage done to the aircraft's reputation by the Comet 1 disasters contributed to Boeing's domination of the jetliner market. The first prototype 707 was flown in 1954 and Douglas launched the DC-8 program in 1955.

Twenty-four airlines flew the Comet and it remained in passenger service for almost three decades, until 1981. Designed over 50 years earlier at the beginning of the jet age, a variant of the Comet, the Nimrod, flying with modern avionics, is still in service with the Royal Air Force.