Plank or skid block


Plank or skid block
Plank or skid block
Ralf Schumacher showing his 10mm thick wooden plank (Toyota 2006)


A wooden or any other homogeneous material strip that was fitted front-to-back down the middle of the underside of all cars in the mid-1990s to check that cars were not being run too close to the track surface, something that was indicated if the wood was worn away. It must be made out of a material with a specific gravity of between 1.3 and 1.45 (to prevent excessively heavy or hard planks producing a performance benefits and lowering the car center of gravity). Typically the plank is wood based, eiterh jabroc a laminate of beechwood, although more exotic blends of woods and resins not unlike MDF have been used. Plank must measure 300mm in width, with a tolerance of 2mm. It must run from the frontmost point of the reference plane at 330mm behind the front wheels centerline to the rear wheels centerline. Skid block may comprise of no more than three pieces, the forward one of which may not be any less than 1000mm in length. Plank must be fixed symmetrically on the car centre line in such a way that no air may pass between it and the surface formed by the parts lying on the reference plane. The lower edge (facing ground) of the front end of the skid block may be chamfered at an angle of 30° to a depth of 8mm, and trailing, rear edge may be chamfered over a distance of 200mm to a depth of 8mm.

When measured through six pre-cut 5cm diameter holes, plank has to have a tolerance of just 1mm on its 10mm thickness. Seven precisely placed holes in the plank allow the cars reference plane to sit directly and exactly on right place on the FIA scrutineering platform, for legality checks over the course of a GP weekend. Any holes made into it must conform to a FIA template (see picture below). Four further 10mm diameter holes are permitted provided their sole purpose is to allow access to the bolts which secure the Accident Data Recorder to the survival cell.

If plank is consumed too much, car can be disqualified. Skid block or 'plank' must run along the reference plane. It is not considered part of the floor for measurement purposes, and is there only to enforce a minimum ride height.
Plank was introduced with intention of FIA to reduce aerodynamic capabilities and bottoming of the cars, following Austrian Roland Ratzenberger death in qualifying for the San Marino Grand Prix in 1994 driving his Simtec, and Ayrton Senna in a Williams car at the San Marino Grand Prix same year during the race.


FIA regulation about plank or skid block


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R.I.P John SurtesMarch 10, 2017 John Surtees (London 11 February 1934 – London 10 March 2017), the only man to win the Formula One and motorcycle grand prix titles has died aged 83. He won four 500cc motorcycling titles - in 1956, 1958, 1959 and 1960 - and the F1 crown with Ferrari in 1964 by a single point. He won six F1 races in 111 starts between 1960 and 1972, and also drove for Honda, Lotus, Cooper, Lola and BRM. He later set up his own F1 team and managed two podium finishes but never won a race before folding in 1978. Today we lost one of the all time greats on two and four wheels. We will miss you John. R.I.P.

Some useful links:

- f1technical.net, a great site with a lot of technical information’s and explanations. Site is updated daily with news from F1 word.

 - autosport.com, This site is a legend. A bible for racing lovers. News from all around the word. Unfortunately, to get access to all news, interviews and to open the site completely you should be subscribed to Autosport magazine. Anyway, great read.

James Allen on F1
- JA.F1 site (or blog) ovned by ITV Sport’s lead commentator on Formula 1 James Allen

Joe Saward blog
- joesaward is the Joe Saward official blog about Formula 1 world. Joe is an journalist, who write primarily about politics in and around motorsport, specifically on the FIA Formula 1 World Championship

Vital F1
 - vitalf1.com/ is another great site for Motor Sports fan’s like me. Site is relatively new, but great fun, with great discussion forum, Formula 1 news and forum.

 GP update
- f1.gpupdate.net, Site with fresh news from Formula 1

Planet F1
 - planetf1, another site with many different articles, news and statistics. Biased toward British teams, but anyway good read.

Gurney flap
 - gurneyflap.com, Great history site. You can learn a lot from this site. Pictures, cars and many many more. Great.

4ormula1 is a database of Formula 1 history and statistics of drivers, teams, grand prix, and all results since 1950

Racecar engineering
-Racecar Engineering, an online magazine with a lot to learn from, a lot of technical information’s and explanations

 - fia.com, La Fédération Internationale de l'Automobile, representing the interests of motoring organisations and motor car users. Head organisation and ruler in auto sport.

 - wikipedia.org, I don’t believe that I have to tell you anything about this site. It’s not about Formula 1 technology, but you can learn a lot about that too.

Sutton Images

grandprix photo

 - carbibles.com, a great site for normal car users. Here you can find explanations of almost everything about your car and how it works. Technical reviews and explanations of some in-car gadgets.

Dare To Be Different
- Daretobedifferent.org Susie Wolff and UK governing body of UK motorsport have joined forces to launch Dare To Be Different, a high-profile new initiative which is about increasing female participation, not just on the track but in all aspects of the sport.