Ertl sported an 'Imperial'-style moustache and full beard. He worked his way through the German Formula Vee and Super Vee, and then on to Formula Three, before a successful switch to Touring Cars. During this period, he gained sufficient sponsorship to enter Formula One, where he drove with various outfits between 1975 and 1980. Ertl was one of the four drivers who helped to get Niki Lauda out of his burning Ferrari in the 1976 German Grand Prix.