The last hangar, Hangar 1. It’s a vast, open space with several large airplanes, including this, the world’s first jet airliner. The Comet was ahead of its time. It also had square windows, which turned out to be a bad idea. This particular aircraft was originally sold to Air France, but after conversion to a Comet 1XB (round windows, a few other changes), it was given to Britain’s Ministry of Supply and converted to a flying laboratory.

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From propeller biplanes to jet bombers: the incredible planes of the Royal Air Force Museum Cosford – CNET