The family name on the signature approving the sale of a complex jet engine part might perhaps have rung alarm bells: Chirac.

It accompanied the sale of a key component called a low-pressure turbine blade by a British distributor to a Florida firm in 2019 and aimed to show that the part, designed for the world¡¯s most widely used jet engine, the CFM56, was authentic.

Four years later, engine maker CFM International, which supplies Airbus and Boeing, has embarked on a worldwide hunt for thousands of parts with suspected false documentation from the same vendor ¡ª some of which have remained undetected for years.