The number 13 was largely eliminated in motor racing, particularly in European Grand Prix and subsequently Formula One, starting in 1926. The decision was driven by intense superstition (triskaidekaphobia) following fatal accidents involving drivers assigned that number.
The first documented fatal accident in Europe involving a car with the number 13 occurred at the II Armangué Trophy on May 21, 1922. Disobeying the instructions of the race officials, the public surged onto the road to observe the wake of a competitor on lap 2, unaware of the arrival of the official Salmson car driven by André Lombard and his mechanic, Paul Honle. Despite efforts to avoid the crowd of spectators, the car crashed into the crowd, killing three people.
The superstition stems from two specific, fatal driver accidents in the 1920s. Paul Torchy was killed on September 19, 1925 while driving a Delage bearing the number 13 at the San Sebastian Grand Prix held at the Circuito Lasarte in Lasarte-Oria, Spain.
The following year, 1926, Italian Count Giulio Masetti suffered a fatal accident in Sclafani Bagni, Sicily during the XVII Targa Florio while also driving a Delage numbered 13.
After these incidents the Automobile Club de France stopped using the number. Since then it has been a tradition not to use the number in top level motor racing, though there have been two occasions when the number has been used in F1. The first was at the Mexican Grand Prix in 1963 when Moises Solana used the number on a BRM at his home event in Mexico City.
The second occasion was in 1976 when Divina Galica tried but failed to qualify for the British Grand Prix in a Surtees.
NASCAR is the one racing group where the number 13 seems not to be a superstitious issue. Among the 70-plus drivers who have driven the number 13 in NASCAR are; Bobby Unser, Mario Andretti, A.J. Foyt, Curtis Turner and Bobby Isaac. In 649 NASCAR races, a number 13 car had just one victory, in 1963, when Johnny Rutherford won a 100-mile Daytona 500 qualifying race in a Chevrolet owned and prepared by Smokey Yunick.
While the number has never been taken to victory lane, it has been around since the beginning when Pat Kirkwood drove it for one race in 1949 when at Langhorne Speedway in Pennsylvania.