A routine inspection by engineers at an aircraft maintenance facility in Lisbon this spring uncovered an audacious fraud that has sent shockwaves through the aviation industry. Workers noticed suspicious signs of wear on a replacement part for a CFM56 engine, the world’s most widely used jet engine model. The part’s paperwork identified it as brand new, but further scrutiny by the engineers revealed the documents had been forged. Their discovery led engine makers Safran and GE to uncover that thousands of counterfeit parts with fabricated certificates have entered the global supply chain through a single obscure distributor based in London