Crooks began his career as an apprentice aeronautical engineer when he was 17 at the Royal Aircraft Establishment based in Farnborough.
From there, he got a job with Toleman Group Motorsport (later Benetton Formula, then Renault F1) as a detail designer.
He worked under Rory Byrne for the next six years, before moving up to chief composite design engineer in 1983.
In 1993, Crooks became Ligier's chief designer under Frank Dernie, but with the arrest of team boss Cyril de Rouvre, which sent the team into decline, Crooks joined Simtek.
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