Instead he called for a special technical inquiry into track maintenance and metal fatigue.

BBC: Rail inquiry report due on Friday

The British-made Comet, the world's first passenger jet, flew in 1952, before designers at de Havilland Aircraft Ltd. fully understood metal fatigue.

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Over the past few weeks, aircraft engineers have found they do not know quite as much about metal fatigue as they thought.

ECONOMIST: Aircraft fatigue

Though it all but destroyed de Havilland, the disaster gave the industry crucial insights into how metal fatigue can rip an aircraft suddenly apart.

ECONOMIST: Aircraft fatigue

The Royal Navy's official inquiry concluded HMS Affray sank because the snort mast, the tube through which the diesel engine "breathed" while the submarine was at periscope depth, snapped because of metal fatigue.

BBC: HMS Affray submarine sinking remembered off Alderney

Even if corrosion, metal fatigue and parts obsolescence were not taking a toll on the planes, potential adversaries are buying better and better air defenses that will make it harder for the bombers to reach their targets in future wars.

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