At the 1981 season-opening grand prix in Long Beach, Team Lotus driver Elio de Angelis was black-flagged in the first practice session. While the scrutineers were happy that their Lotus 88 cars complied with the rulebook, FISA - the FIA's subcommittee responsible for governing Formula 1 - was less so.
The team's innovative twin-chassis concept, built into the 88 to push the limits of what ground-effect aerodynamics could achieve, was judged to be completely illegal - being barred from even leaving the pits in practice for that year's US Grand Prix West.
At the start of the '80s, the ground-effect revolution was already out of control. Like most tide-turning innovations in F1's history, it was up to one of the sport's greatest visionaries to light the touchpaper: Colin Chapman, a genius wrapped in a moustache and a sporadically-airborne black corduroy cap.