Louis Blériot was flying on a broken ankle. His monoplane — a fragile structure of spruce, ash, and rubberised canvas — had a 25-horsepower engine that overheated on long runs. He had no compass. No radio. No life jacket. As he climbed to 250 feet over the Pas-de-Calais and pointed his nose roughly north-west, the cliffs of Dover were not visible. He had, essentially, no idea where England was.

It was 4:41 AM when he lifted off from a field near Calais. He followed the French destroyer Escopette, which had been assigned as his escort vessel, for the first ten minutes. Then the destroyer fell behind. Then the mist closed in. For ten minutes — he would describe them as the longest of his life — Blériot flew alone over open water with no reference to the surface below and no landmarks ahead. His engine started to overheat. He watched the temperature gauge climbing and prayed for rain.

Rain came. A brief shower cooled the engine just enough. Then the white cliffs of Dover appeared through the mist, and Blériot steered toward them. He missed his intended landing spot — a meadow arranged by a French journalist named Charles Fontaine who was there to greet him — and instead crash-landed on a hillside near Dover Castle, snapping his propeller and one of his wheel struts. He climbed out, uninjured.

Why It Terrified Britain

The English Channel had been Britain’s greatest natural defence for a thousand years. No foreign army had successfully crossed it since 1066. Now a Frenchman with a 25-horsepower engine had done it in 37 minutes. British newspapers reacted with a mixture of jubilation and barely-concealed alarm. “England is no longer an island,” wrote one editorial. Lord Northcliffe, who had offered the £1,000 prize, immediately grasped the military implications: “The possibilities of the aeroplane as an instrument of warfare are in the minds of all thoughtful men.”

Blériot received the prize and instant global celebrity. Orders for his Blériot XI poured in from around the world. The aircraft he flew that morning would go on to be used in the early months of World War I — including by Harriet Quimby, who made her own historic Channel crossing three years later. The monoplane that changed history is still preserved at the Musée des Arts et Métiers in Paris, looking every bit as flimsy as it must have on that July morning in 1909.

Blériot went on to build aircraft for the French military and remained a central figure in aviation until the 1930s. He died in 1936, aged 64 — just as the aircraft he had done so much to inspire were being built into weapons for a second world war. The Channel he crossed in 37 minutes would soon be contested by the aircraft of the Battle of Britain, machines a thousand times more powerful than his little XI. But it all started with a broken ankle, an overheating engine, and ten minutes of fog over the Channel.

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