Upon arriving in Europe on his own in early 1955, Brabham based himself in the UK, where he bought another Cooper to race in national events.
His crowd-pleasing driving style initially betrayed his dirt track origins: as he put it, he took corners "by using full [steering] lock and lots of throttle".
Visits to the Cooper factory for parts led to a friendship with Charlie and John Cooper, who told the story that after many requests for a drive with the factory team, Brabham was given the keys to the transporter taking the cars to a race.
Brabham soon "seemed to merge into Cooper Cars": he was not an employee, but he started working at Cooper daily from the midpoint of the 1955 season building a Bobtail mid-engined sports car, intended for Formula One, the top category of single seater racing.
He made his Grand Prix debut at the age of 29 driving the car at the 1955 British Grand Prix.
It had a 2-litre engine, half a litre less than permitted, and ran slowly with a broken clutch before retiring.
Later in the year Brabham, again driving the Bobtail, tussled with Stirling Moss for third place in a non-championship Formula One race at Snetterton.
Although Moss finished ahead, Brabham saw the race as a turning point, proving that he could compete at this level.
He shipped the Bobtail back to Australia, where he used it to win the 1955 Australian Grand Prix before selling it to help fund a permanent move to the UK the following year with his wife Betty and their son Geoff.

Brabham briefly and unsuccessfully campaigned his own second hand Formula One Maserati 250F during 1956, but his season was saved by drives for Cooper in sports cars and Formula Two, the junior category to Formula One.
At that time, almost all racing cars had their engines mounted at the front but Coopers were different, having the engine placed behind the driver, which improved their handling.
In 1957, Brabham drove another mid-engined Cooper, again only fitted with a 2-litre engine, at the Monaco Grand Prix.
He avoided a large crash at the first corner and was running third towards the end of the race when the fuel pump mount failed.
After more than three hours of racing, the exhausted Brabham, who "hated to be beaten", pushed the car to the line to finish sixth.
The following year, he was Autocar Formula Two champion in a Cooper, while continuing to score minor points-scoring positions with the small-engined Coopers in the World Drivers' Championship and driving for Aston Martin in Sportscars.
His schedule necessitated a considerable amount of travel on the roads of Europe.
Brabham's driving on public roads was described as "safe as houses", unlike many of his contemporaries—on the way back from the 1957 Pescara Grand Prix, passenger Tony Brooks took over driving after Brabham refused to overtake a long line of lorries.
In late 1958, Brabham rekindled his interest in flying and began taking lessons.
He bought his own plane and on gaining his licence began to make heavy use of it piloting himself, his family, and members of his team around Europe to races.

In 1959, Cooper obtained 2.5-litre engines for the first time and Brabham put the extra power to good use by winning his first world championship race at the season-opening Monaco Grand Prix after Jean Behra's Ferrari and Stirling Moss's Cooper failed.
More podium places were followed by a win in the British Grand Prix at Aintree after Brabham preserved his tyres to the end of the race, enabling him to finish ahead of Moss who had to pit to replace worn tyres.
This gave him a 13-point championship lead with four races to go.
At the Portuguese Grand Prix at Monsanto Park, Brabham was chasing race leader Moss when a backmarker moved over on him and launched the Cooper into the air.
The airborne car hit a telegraph pole, throwing Brabham onto the track, where he narrowly avoided being hit by one of his teammates but escaped with no serious injury.
With two wins each, Brabham, Moss, and Ferrari's Tony Brooks were all capable of winning the championship at the final event of the season, the United States Grand
Upon arriving in Europe on his own in early 1955, Brabham based himself in the UK, where he bought another Cooper to race in national events. His crowd-pleasing driving style initially betrayed his dirt track origins: as he put it, he took corners "by using full [steering] lock and lots of throttle". Visits to the Cooper factory for parts led to a friendship with Charlie and John Cooper, who told the story that after many requests for a drive with the factory team, Brabham was given the keys to the transporter taking the cars to a race. Brabham soon "seemed to merge into Cooper Cars": he was not an employee, but he started working at Cooper daily from the midpoint of the 1955 season building a Bobtail mid-engined sports car, intended for Formula One, the top category of single seater racing. He made his Grand Prix debut at the age of 29 driving the car at the 1955 British Grand Prix. It had a 2-litre engine, half a litre less than permitted, and ran slowly with a broken clutch before retiring. Later in the year Brabham, again driving the Bobtail, tussled with Stirling Moss for third place in a non-championship Formula One race at Snetterton. Although Moss finished ahead, Brabham saw the race as a turning point, proving that he could compete at this level. He shipped the Bobtail back to Australia, where he used it to win the 1955 Australian Grand Prix before selling it to help fund a permanent move to the UK the following year with his wife Betty and their son Geoff.
Brabham briefly and unsuccessfully campaigned his own second hand Formula One Maserati 250F during 1956, but his season was saved by drives for Cooper in sports cars and Formula Two, the junior category to Formula One. At that time, almost all racing cars had their engines mounted at the front but Coopers were different, having the engine placed behind the driver, which improved their handling. In 1957, Brabham drove another mid-engined Cooper, again only fitted with a 2-litre engine, at the Monaco Grand Prix. He avoided a large crash at the first corner and was running third towards the end of the race when the fuel pump mount failed. After more than three hours of racing, the exhausted Brabham, who "hated to be beaten", pushed the car to the line to finish sixth. The following year, he was Autocar Formula Two champion in a Cooper, while continuing to score minor points-scoring positions with the small-engined Coopers in the World Drivers' Championship and driving for Aston Martin in Sportscars. His schedule necessitated a considerable amount of travel on the roads of Europe. Brabham's driving on public roads was described as "safe as houses", unlike many of his contemporaries—on the way back from the 1957 Pescara Grand Prix, passenger Tony Brooks took over driving after Brabham refused to overtake a long line of lorries. In late 1958, Brabham rekindled his interest in flying and began taking lessons. He bought his own plane and on gaining his licence began to make heavy use of it piloting himself, his family, and members of his team around Europe to races.
In 1959, Cooper obtained 2.5-litre engines for the first time and Brabham put the extra power to good use by winning his first world championship race at the season-opening Monaco Grand Prix after Jean Behra's Ferrari and Stirling Moss's Cooper failed. More podium places were followed by a win in the British Grand Prix at Aintree after Brabham preserved his tyres to the end of the race, enabling him to finish ahead of Moss who had to pit to replace worn tyres. This gave him a 13-point championship lead with four races to go. At the Portuguese Grand Prix at Monsanto Park, Brabham was chasing race leader Moss when a backmarker moved over on him and launched the Cooper into the air. The airborne car hit a telegraph pole, throwing Brabham onto the track, where he narrowly avoided being hit by one of his teammates but escaped with no serious injury. With two wins each, Brabham, Moss, and Ferrari's Tony Brooks were all capable of winning the championship at the final event of the season, the United States Grand
Jack Brabham