Burt strut
Encyclopedia
A Burt strut or timing strut is a black, rectangular plate attached to the front of a competition vehicle, usually a racing car, to provide a standardised, repeatable method by which to break a timing light beam at the start and finish of events timed to high-degrees of accuracy. These events are commonly those in which competitors race against the clock, rather than physically against another vehicle, such as sprint or hillclimb
races. The strut was invented in 1967 by Ron Smith; manager, chief mechanic and future husband to 1970 British sprint champion Patsy Burt
. As the strut made its first appearance on the front of Burt's McLaren-Oldsmobile
her name was used as its official title. In recent years the generic term timing strut has also become common.
The Burt strut was introduced to replace previous timing mechanisms, whereby a chock with a sensor was placed behind the rear wheel of a car at the start. Due to the chock being related to the rear of the car at the start, and readings being taken from the front of the car at the finish, the degree of precision within which cars could be timed was limited. As most British hillclimb courses are somewhat less than 1500 yards (1372 m) long, it is not uncommon for competitors' times to be separated by only a few hundredths of a second. The introduction of theoretically more accurate light beam timing required that all cars provide a consistent surface with which to break the beam at both start and finish of the timed section. However, owing to the variable shape of vehicles and inconsistencies in the placing of the beam sensors, this was not a simple condition to meet before the introduction of the Burt strut.
The Burt strut has since been made compulsory in most national and international timed sprint events. Within the United Kingdom
the rules governing the size and position of the strut are determined by the Royal Automobile Club
Motor Sports Association
. The strut is currently defined in the MSA Competitors' Yearbook (the Blue Book) regulations document as being a single rectangular plate, painted matt black on both sides, no less than 254 mm in height and 51 mm in width, the lower edge of which should be mounted not more than 200 mm from the ground, with the upper edge being at least 454 mm from the ground. The strut must be the most forward part of the vehicle. There are no restrictions on the material used to make the strut, so long as the strut itself conforms to the regulations, and some designs can be very simple to construct.
Hillclimbing
Hillclimbing is a branch of motorsport in which drivers compete against the clock to complete an uphill course....
races. The strut was invented in 1967 by Ron Smith; manager, chief mechanic and future husband to 1970 British sprint champion Patsy Burt
Patsy Burt
Patricia Mary "Patsy" Burt was a British motor racing driver.During a long and varied career, Patsy Burt won many British national-level competitions, and was the first female driver ever to win both the Brighton Speed Trials and the RAC National Sprint Championship...
. As the strut made its first appearance on the front of Burt's McLaren-Oldsmobile
Oldsmobile
Oldsmobile was a brand of American automobile produced for most of its existence by General Motors. It was founded by Ransom E. Olds in 1897. In its 107-year history, it produced 35.2 million cars, including at least 14 million built at its Lansing, Michigan factory...
her name was used as its official title. In recent years the generic term timing strut has also become common.
The Burt strut was introduced to replace previous timing mechanisms, whereby a chock with a sensor was placed behind the rear wheel of a car at the start. Due to the chock being related to the rear of the car at the start, and readings being taken from the front of the car at the finish, the degree of precision within which cars could be timed was limited. As most British hillclimb courses are somewhat less than 1500 yards (1372 m) long, it is not uncommon for competitors' times to be separated by only a few hundredths of a second. The introduction of theoretically more accurate light beam timing required that all cars provide a consistent surface with which to break the beam at both start and finish of the timed section. However, owing to the variable shape of vehicles and inconsistencies in the placing of the beam sensors, this was not a simple condition to meet before the introduction of the Burt strut.
The Burt strut has since been made compulsory in most national and international timed sprint events. Within the United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
the rules governing the size and position of the strut are determined by the Royal Automobile Club
Royal Automobile Club
The Royal Automobile Club is a private club and is not to be confused with RAC plc, a motorists' organisation, which it formerly owned.It has two club houses, one in London at 89-91 Pall Mall, and the other in the countryside at Woodcote Park, Surrey, next to the City of London Freemen's School...
Motor Sports Association
Motor Sports Association
The Motor Sports Association , is the official governing body of motorsport in the United Kingdom.-Responsibilities:...
. The strut is currently defined in the MSA Competitors' Yearbook (the Blue Book) regulations document as being a single rectangular plate, painted matt black on both sides, no less than 254 mm in height and 51 mm in width, the lower edge of which should be mounted not more than 200 mm from the ground, with the upper edge being at least 454 mm from the ground. The strut must be the most forward part of the vehicle. There are no restrictions on the material used to make the strut, so long as the strut itself conforms to the regulations, and some designs can be very simple to construct.