’Cage fighters

Fifty years have passed since the FIA mandated the installation of the ‘Safety Cage’ in closed-cockpit racecars, as set out in Appendix J to the International Sporting Code of 1971.

Since then, the regulations have evolved from a simple set of guidelines to a strict list of rules governing design, manufacture, installation and testing of the structures.

In 2004, the FIA introduced Technical List no. 35 (TL35), a list of testing houses permitted to test ’cage structures that do not abide completely to the regulations, but could still be accepted thanks to the homologation process. In this anniversary year, we take a close look at the safety cage homologation procedure, and compare the performance of some typical design alternatives.

Article 253 of Appendix J (J253) has, for decades, been the reference regulation for ’cages in motorsport. J253 has described the minimum requirements for one to be fabricated and installed without the need for separate testing and homologation – any ’cage made according to these rules would be accepted for competition without proof of strength.

Any design that deviated from J253 could be proposed to the FIA for homologation, upon which a new set of regulations would apply, namely the Homologation Regulations for Safety