Bell’s chosen name for the super-medium 525 helicopter, Relentless, has become equally appropriate for the company’s lengthy pursuit of airworthiness certification.
After originally promising to receive a US Federal Aviation Administration Part 29 certificate in 2015 upon programme launch six years ago, Bell now expects the required validation for the 19-seat, fly-by-wire helicopter to come four years later in 2019, says Bell’s vice president of 525 sales and business development Larry Thimmesch.
The company plans to complete certification flight testing by the end of this year, followed by FAA approval in early 2019, he says.
The first five production aircraft are now being built in Amarillo, Texas, Thimmesch adds, but their customers have not been announced. Thimmesch says he knows the identity of the 525 launch operator, but the chosen buyer remains a secret.
Likewise, Bell still declines to release the backlog of firm orders and letters of intent for the 525 programme. A list of customers with letters of intent for about 80 525s has not been updated in two years. Bell displayed a 525 mock-up in the livery of oil and gas and search and rescue operator Bristow Helicopters, but the latter has not yet signed any orders or a letter of intent for the type.
The 525 resumed flight testing last July, which was a year after a test aircraft crashed and killed two pilots. In a planned high-speed flight test with an unusually low rotor speed, a main rotor blade struck the tail boom. An official investigation traced the root cause to severe vibrations, which created a closed-loop chain reaction of accidental cyclic commands by the pilot that caused the aircraft to shake even more. Bell fixed the problem by adding a software filter for the fly-by-wire cyclic controls, Thimmesch says.