Chain Bear's latest video takes a look at the latest details we've seen from Formula 1 about the plans for its 2021 rules revolution - specifically the return of ground effect aerodynamics. The approach developed by Lotus towards the end of the 1970s proved so effective that it was banned after just a few years on safety grounds. Chain Bear explains how the concept works, why it was so dangerous in the past, and how its reintroduction will be managed differently to prevent a repeat of the frightening breed of cars that were produced last time around