Claim: The Hawker Tempest, one of the most powerful fighters of World War II, was a brand new design, completely separate from the Typhoon aircraft that came before it.
Evidence: The Tempest emerged as one of the most powerful fighters of World War II and was the fastest single-engine propeller-driven aircraft of the war at low altitude. The Tempest, originally known as the Typhoon II, was an improved derivative of the Hawker Typhoon, intended to address the Typhoon's unexpected deterioration in performance at high altitude by replacing its wing with a thinner laminar flow design.