Complete the following sentence: Rolt competed in three Formula One World Championship races, the British Grands Prix of 1950, 1953, &amp; 1955, but all three outings ended in retirement. <unk> <unk> <unk>
1950 British Grand Prix, the first-ever round of the F1 World Championship, he started 10th on the grid in an ERA that had been qualified by Peter Walker, but the gearbox failed after four laps. 1953 race, once again he started from 10th, but a half shaft on his Connaught failed after 70 laps.<unk> 1953 race, once again he started from 10th, but a half shaft on his Connaught failed after 70 laps. ️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️ In what was to be the last F1 outing for both drivers: their Connaught started 14th and retired with transmission problem after 18 laps. Stirling Moss asserts that Rolt would have been among the top GP drivers, if he raced regularly.