The Bell Aircraft Corporation has been working on the 525 Relentless helicopter for over 13 years. Initially unveiled at the Dallas Heli-Expo in 2012, the 525 was set to be the first commercial helicopter with Fly-By-Wire technology. Certification was initially hoped for by 2017, but as of 2025, it remains uncertified.
Petroleum Helicopters International (PHI), the initial launch customer, withdrew before the prototype’s maiden flight in 2014. The flight eventually took place in 2015, with Bell still aiming for a 2017 certification. However, in 2016, the Federal Aviation Administration (FAA) suggested special conditions for certification due to the Fly-By-Wire Flight Control System (FBW FCS). An excerpt from a Federal Register document noted: “The control functions of the FBW FCS and its related systems affect the structural integrity of the rotorcraft.”
In 2016, a crash during testing exposed flaws caused by FBW system implementation. The helicopter was demonstrating recovery from a single-engine failure when vibration developed and propagated into the cockpit. This led to a “biomechanical feedback loop,” causing catastrophic failure and resulting in both operators’ deaths.
Bell resumed flight testing in July 2017 after addressing these issues by changing control laws and re-tuning filters. By late 2018, significant progress had been made towards US certification despite ongoing tests.
As of July 2024, Vertical Mag reported that Bell CEO Lisa Atherton stated: “We’re really close,” (…) “We have less than a handful of TIAs [type inspection authorization flights] to complete before entering into function and reliability testing.” Bell began taking orders for the aircraft last year with deliveries expected in 2026.
Despite challenges, Bell’s advancements include innovations like touchscreen glass flight decks and greener materials. If certified soon, it will serve various sectors including energy and military applications.
