Graduating to International competition, he entered the 1913 Daily Mail Circuit of Britain Air Race, setting out to win the £5,000 prize.
Hawker, along with mechanic and friend Harry Kauper, turned out to be the only contestants to start the race that year, flying a new Sopwith Circuit of Britain floatplane, fitted with a six-cylinder 100hp Green engine. Of the other entrants, Gordon England had damaged one of the floats on his radical 3-engine machine, designed by James Radley.
Meanwhile, the only other entrant, Samuel Cody (the first man to fly in the United Kingdom), had fatally crashed at Farnborough just a week before the start of the competition.
As it turned out (and despite being the absolute favourites) Hawker was taken ill from either sunstroke or the engine fumes (or both) during the early legs between Southampton and Great Yarmouth and so well-known cross-channel pilot Sydney Pickles was sent for to continue the flight whilst Hawker recovered.
Hawker had the opportunity to drive Louis Coatalens' 350hp V12 18.3-litre Sunbeam at the second of the post-war car race meeting at Brooklands on 19th June 1920. During the practice session however, a front tyre burst as he drove high-up on the famous Brooklands Banking. He wrestled with the big car just long enough to keep it on the track and managed to reach the railway straight where he subsequently crashed through the fence and down a 4ft drop towards the railway line. Thankfully, he stopped short of meeting a London to Portsmouth locomotive.
Hawker was unhurt, declaring himself 'impressed by the very nice car'.
Later that day, Harry also took part in the 4th race of the day, this time in a smaller, 6-cylinder Indianapolis Sunbeam where he beat his rival's Vauxhall at an average speed of 99.5mph.