What does a test pilot actually do—and why would a decorated fighter pilot risk everything to become one?

After surviving more than fifty combat missions in the Falklands War, achieving three air-to-air victories and receiving the Distinguished Service Cross, Stephen Harrison-Thomas might have expected a secure future in the Royal Navy.

Instead, he found himself fighting to hold on to a career that was already beginning to disappear.

Testing Skies follows his selection for the Empire Test Pilots’ School and his move into the demanding, secretive and dangerous world of military flight testing at Boscombe Down. There, courage alone was not enough. Every flight had to be planned, measured, analysed and explained. A vague answer could mislead engineers. A confident mistake could remain hidden in an aircraft for years.

From spinning the Jet Provost, Hawk and Hunter to testing new systems on the Sea Harrier, Harrison-Thomas reveals what test pilots really do: explore the limits of aircraft, identify dangers before frontline crews encounter them and turn experimental technology into something that can be trusted in combat.

At the heart of the book is the transformation of the Sea Harrier. Drawing on his experience of the Falklands and the limitations of the Blue Fox radar, he became involved in the development of the next generation of the aircraft, including air-to-air refuelling, the powerful Blue Vixen radar and the AIM-120 AMRAAM missile. These systems promised to give future Sea Harrier pilots what had been missing in 1982: the ability to find enemy aircraft earlier, track them through clutter and destroy them before they reached the fleet.

But while the aircraft was being given a future, his own remained uncertain.

Still only in his twenties, surrounded by older and more experienced pilots and engineers, he battled self-doubt, professional rivalry and the fear of becoming a civilian before he was ready. Out of uniform, without rank, medals or a fighter aircraft beside him, who would know what he had achieved—or believe the stories he had to tell?

Dramatic, technically detailed and deeply personal, Testing Skies is a story of ambition, danger, loss and identity. It is for anyone fascinated by aviation, military history or the hidden world of flight testing—and for anyone who has ever tried to prove they belonged while the life they wanted was slipping away.