The Fitch Barrier was originally conceived for broad use in highway safety. In that application it has saved thousands of lives on roadways from Maine to California.
Due to its superior energy absorption and ease of replacement, it was natural that the barrier would find use on the more enlightened racing circuits. Of course the original barriers were tested at Lime Rock, where inventor John Fitch was the track manager. They were used on the pit wall end and many a driver was saved while they were there. Later, under a different manager, the Fitch Barriers were removed. After two drivers lost their lives, they were put back. The barriers were also used at Watkins Glen and Infineon Raceway (formerly Sears Point).
An example of how the Fitch Barriers work in racing was seen in 1996 when a Spec Racer Ford hit them in an SCCA club race. Driver Gary Marquart was coming out of turn 11, trying to pass another car and he ran out of racing room. Rather than hit the other car, he went to the pit wall end.
The pit wall at Infineon Raceway is steel and concrete, protected by a banded tire assembly 4 tires high, 2 tires wide and 3 tires deep, with Fitch Barriers behind them. The Fitch Barriers were the conventional highway units with approximately 300 pounds of sand in each (the top 1/3rd was full, the bottom 2/3rds empty).
The energy absorber was struck at between 80 and 90 mph. The tire assembly, free to move, went into the Fitch Barriers and the sand was dispersed in Newton’s momentum exchange, as they were intended to, and absorbed the energy of the impact. The tire bundle went up in the air and came down in the pit lane.
The pit wall absorber was hit off center so that the car spun violently (“like a helicopter blade” said some observers) and the force of the impact was also lessened by the spin. The car came to rest at the edge of the race course, about 30 feet beyond the end of the barrier.
The driver was not injured in any way. He leapt from his car after the accident. That night he went dancing. The nose of his car was knocked off and the total repair bill was only $1800. The Fitch Barrier once again performed as expected.