Eva Peron, the legendary Evita, kissed him after he won the 1951 Grand Prix of Argentina. His friend George Barker, the poet, described him as “a tall Jack with the sun on his wrist and a sky stuffed up his sleeve.”
Mr. Fitch, a lanky, graceful man who died on Monday at 95, put it more simply: “I’ve always needed to go fast.”
Sometimes it seemed Mr. Fitch was trying to outdistance time itself. At 70, he set a speed record — for driving backward, reaching 60 miles per hour at Lime Rock Park, the track he helped build in Connecticut.
As a race driver Mr. Fitch lived with his wife, the former Elizabeth Huntley, in an apartment in Paris, a villa in northern Italy and a house in Switzerland. After the war he settled in Palm Beach, Fla., and hobnobbed with Orville Wright, Noël Coward and lots of Kennedys. He and his wife later settled in his family’s 19-room ancestral 18th-century house in Salisbury, Conn.
As glamorous as his racing life was — Mr. Fitch led Corvette’s first racing team and was the only American to join Mercedes’s fabled stable of drivers — his greatest achievement can be found on public highways. He invented the Fitch Inertial Barrier, a cluster of plastic barrels filled with varying amounts of sand that progressively slow and cushion a car in a crash. Devised in the 1960s and commonly positioned at exit ramps and abutments along interstates, the barrier is believed to have saved more than 17,000 lives.
His patent for that invention is one of 15 he owned, most of them for safety improvements for motor racing and driving on highways. A notable exception is his patent for a system for steering hot-air balloons.
A college dropout, Mr. Fitch said he had learned just enough engineering to accomplish what he wanted to accomplish. His genes could not have hurt: an ancestor invented the first plow on wheels during the Revolutionary War, and his great-great-grandfather John Fitch invented the steamboat.
A grandfather, Asa Fitch, made a fortune from Fitch’s Chewing Gum, which he invented in his kitchen. His father, Robert, was an early builder of horseless carriages in Indiana.
John Cooper Fitch was born in Indianapolis on Aug. 4, 1917. His parents divorced when he was 6, and his mother married George Spindler, president of the Stutz Motor Car Company. An amateur racecar driver, Mr. Spindler took young John for spins on the Indianapolis Motor Speedway.
He attended military school and studied civil engineering at Lehigh University in Pennsylvania for a year. Answering the call of the open road, he bought an Indian motorcycle and rode it to New Orleans, where he traded it for a Fiat 500 automobile and drove it to New York, stopping only for gas.
In 1939, he used a small inheritance to hop a freighter for Europe and found his way to London, where he fell in love with a ballet dancer and lived with Communist intellectuals in grain barges on the Thames.
Enlisting in the Army Air Forces in 1941, he went on to fly a P-51 Mustang and shot down a German Messerschmitt Me 262, the first operational jet fighter, as it was taking off. He was later shot down himself and spent three months in P.O.W. camps.
After the war, as a member of Palm Beach society, he started racing yachts. He liked to tell the story of how he met the Duke of Windsor at one soiree: they were relieving themselves on a bush at the time. The duke became a friend.
Mr. Fitch had fallen in love with sports cars when he saw a race in England, and after briefly selling them at a Mercedes-Benz dealership he opened in White Plains, he began racing an MG roadster on Long Island. In 1951 he won the Argentina race in an Allard sports car powered by a Cadillac V-8 engine and went on to win 12 of 13 races in the United States. The Sports Car Club of America anointed him its first national champion.