The Bell 525 Relentless is an American medium-lift helicopter, under development by Bell Textron. The Bell 525 was unveiled at the 2012 Heli-Expo in Dallas, Texas in February 2012. The helicopter first flew on 1 July 2015. It is designed to transport up to 19 passengers. Development The Bell 525’s maiden flight was planned for late 2014. PHI, Inc.