Readers letters
Alec Collins features the Comet airliner as an engineering disaster, and so the problems with the Comet 1 must be so remembered.
But in a Journal such as ours, this should be echoed as the international disaster that it was. The Parliamentary Court of Inquiry Report C.A.P.127 of 1955 was and is a remarkable piece of work. Unchallenged, it remains on the shelves of national libraries as available to back serious comment.
Paragraph 17. conveys the essential fact that, "For the design of the basic structure of the cabin they adopted a multiple of the working pressure, P, in excess of current requirements in any country. The British Civil Airworthiness Requirements (B.C.A.R.) called for - - -. These requirements were the same as those of the International Civil Aviation Organisation (I.C.A.O.) and also for this country for military aircraft."
The Paragraph and those following through to 20, etc, talk dauntingly to modern, and non aerospace eyes, of proof pressures at 1.33 P, (under which the cabin must show no signs of permanent deformation), together with a design' pressure of 2P (at which the material may reach its ultimate strength). De Havillands used a design pressure of 2.5 P and tested the cabin to 2 P.
Subsequent to the accidents, in spring 1954 the world rethought its design parameters in following through the findings of the Court of Enquiry, much new thinking was published on the subject of fatigue, the material sciences advanced. The prime competitor in the Boeing 707 family having flown in July 1954 was developed in military service, and entered civilian service service with Pan American in October 1958, just pipped at the post by BOAC's Comet IV across the Atlantic. The Russian Tu 104 airliner, derived from the Tu16 bomber, entered service to London in March 1956 and was for two years the worlds only operational type.
With regard to reference to the 'clever bit' as the engines this is not contentious. The Ghost engines were sound in antecedents and performance. Their designer Frank Halford had surveyed the civil aviation field in his lecture to the Royal Society, 'Jet Propulsion' in May 1946, this under the chairmanship of Air Commodore Frank Whittle, C.B.E. who conveyed his warm support. This another text worth seeking out from the Library. The engine took the world altitude record in March 1948 at 59,446 ft as flown in a DH 'Vampire. It was the first to be Type approved for civil aviation, and powered both the Swedish J29 'Tunnen'and the R.A.F. 'Venom' fighters in first successful ventures into swept wing flighter operations.
Peter Stokes
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