Everybody knows that nowadays we have helmets with anti-fog visors, pinlock systems, lock systems that keeps the visor slighty opened and even "heat systems" to keep the visor "hot".. But in the past, there wasn´t air ducts or this kind of technology to prevent the fog, so the drivers needed to do some improvisations, here are some of them:
James Hunt put a white tape to hold his visor a little bit opened, in this 1975 picture:
As we saw in the "Rush" movie, in the 1976 Japanese Grand Prix. Alastair Caldwell did four holes, two in each side of James helmet, to avoid fogging. James complained about the water entering in the holes, but Alastair said "the water will not enter if you stay in the lead, far from the water spray of the other cars".
Some years ago I saw an original Emerson Fittipaldi helmet, from his last Indycar season, 1996, and I saw the small holes in the both sides of the visor.
Nigel Mansell used to put an amount of tape inside the lower part of the visor, to keep it slightly opened:
I would like to know a little more curiosities about old techiniques to prevent the visor from fog in the rainy or cold days