The price of progress

READERS of the article on the Comet jet airliner under the general heading of ‘Britain’s greatest masterpieces’

(May 4) might have wondered if the accolade was merited, noting the fatal crashes that led to its grounding. Investigations revealed that there were metal-fatigue failures due to poor window design and inadequate riveting of the structure, which was repeatedly pressurised and depressurised. But the designs were improved: oval windows replaced square ones and the skin thickness was increased. Comet 4 flew successfully until 1981, but was overtaken by Boeing’s 707. After a major modification, it entered service as Hawker Siddeley Nimrod, as an RAF sea- and land-search plane, as a long-haul carrier and in the Falklands campaign. The last Nimrod was taken out of service in 2011 —so the aeroplane had a service life of more than 60 years. The Comet moved aviation into a new era, but it came at a price. Dr David A. Harris, East Sussex