Low-speed handling and hovering was the focus of the maiden flight.

The first Bell 525 Relentless N525TA airborne at Amarillo, Texas, on July 1, 2015.

Bell 525 trials included hot weather testing in Arizona

All four Relentless prototypes came together for this formation photo early in September 2020. The aircraft's retractable undercarriage combines with its clean airframe to deliver considerable fuel burn savings compared with helicopters offered by Bell's competitors

On July 7, 2017 Bell Helicopter announced the Bell 525 Relentless programme has resumed flight test activity after receiving experimental certificate renewal from the Federal Aviation Administration (FAA). Bell Helicopter President and CEO, Mitch Snyder said the company had worked with the National Transportation Safety Board and the FAA since the crash of the first prototype FTV-1, registration N525TA, on July 6 last year, adding the team is focused on certification in 2018.

Bell brought a twin-engine 525 Relentless prototype to Heli Expo.

A 525 Relentless - registration N525TY (c/n 62015) - during a test flight.

At first glance, Bell's 525 leaves an impression of sleek lines and huge windows. A true 21st-century helicopter, it has all the capability to match its futuristic looks

A large-diameter, five-bladed main rotor provides the Relentless with low rotor disc loading, reducing downwash. This is particularly important for SAR and casevac/HEMS operators

Hot-and-high trials are essential in proving a helicopter’s ability to land and take off at altitude

The Relentless boasts a simple, uncluttered cockpit arrangement, thanks in part to its incorporation of sidestick controllers

The ARC Horizon flight deck in the Bell 525 Relentless uses Garmin G5000H avionics, including four large screens.

The Bell 525 is the first commercial helicopter to have a fully fly-by-wire cockpit.

The Garmin G5000H avionics suite installed in the Relentless includes four primary and three secondary screens, including this touchscreen in the central console

Even equipped for the somewhat utilitarian mission of oil and gas support, the Relentless offers comfortable accommodation. Byron Ward, the Bell 525 programme vice president, said that even with 16 seats installed, every passenger can touch an emergency exit from their seat

A helicopter that will accommodate 16 passengers in comfort inevitably offers luxurious options for VIP and corporate configurations. The large cabin windows are particularly evident in this mock-up view

Customers have been involved in designing more than 50 different role kits for the Relentless.

The Lift Assist Tail Boom Design features the vertical tailplane cantered slightly to the left. This mock-up lacks the sponsons for the main undercarriage, which were added in 2014.

Bell aims to capture a large percentage of the booming energy platform support role with the Model 525 Relentless. PHI was the first potential customer identified, the original mock-up being unveiled in its colours.

Offshore oil and gas transport is just one of the roles the Bell 525 Relentless is targeted at.

Bell is also promoting the Model 535 Relentless for the maritime search and rescue role.

Bell has designed the 525 to be repurposed - for example, from corporate transport to firefighting.