Pillar (car)

Typical pillar configurations of a sedan (three box), station wagon (two box) and hatchback (two box) from the same model range.

Typical pillar configurations of a sedan (three box) and station wagon (two box) from the same model range.

Diagram of a five-door hatchback (two-box) superimposed over the station wagon (two-box) from the same model range — in this case, both with a D-pillar.

Pillars are the vertical supports of the greenhouse of an automobile — known respectively as the A, B, C or D-pillar moving in profile view from the front to rear.

In American and British English, the pillars are sometimes referred to as posts (A-post, B-post etc.).

Applications

Consistently denoting a roof's successive structural member provides a reference point for discussion. As an example, rescue teams employ pillar nomenclature to facilitate communication when cutting vehicles, for example with the jaws of life.

Pillars are implied, whether they exist or not; where a design's greenhouse features a break between windows or doors without vertical support at that position, the non-existent pillar is "skipped" when naming the other pillars. Thus a 2-door coupé or a three box designed sedan could have its rearmost pillar called the C-pillar even in the absence of a B-pillar.

Vehicles omitting the B-pillar were once widely called pillarless hardtops or hardtops. In the early 1970s, General Motors broadened their definition of "hardtop" to include models with a B-pillar: "up to then, everybody thought a hardtop was a car without a center pillar."^[1]

Pillars are implied, whether they exist or not; the non-existent pillar is "skipped" when naming the other pillars.

In addition to the pillar nomenclature derived from viewing an automobile in profile, some older cars have a two-part windshield or split rear window, with the two halves separated by a pillar.

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  A photographic typology illustrating variations of the design of the C-pillar

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  From left to right: C, B2, B1, and A-pillars, with small quarter glass in both doors (AMC Ambassador)

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  A stretch limo with five pillars (Lincoln Town Car)

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  A-pillar blind-spot accident

See also

• Automobile design
• Blind spot (automobile)
• Driver visibility

References

1. ^ Lund, Robert (June 1974). "Detroit Listening Post — same cars, different label". Popular Mechanics 141 (6): 42. http://books.google.com/books?id=YdQDAAAAMBAJ&pg=PA42&dq=definition:+Automobile+pillar&lr=&ei=AxZXS5fxJ4y4NvWN9e8M&client=safari&cd=22#v=onepage&q=&f=false. Retrieved 2010-01-20. 

External links

• Slimmer Commodore windscreen pillars coming - design process into the 'A' pillar
• flickr photo group - "Art of Automotive C Pillars" group created 2005-07-26; webpage accessed 2008-02-10