Bell Helicopter has resumed flight testing of its new Bell 525 Relentless super medium helicopter, which was suspended following fatal crash of the first prototype in July 2016, during a flight test over Texas.
The third prototype (FTV-3) commenced flight testing after receiving experimental certificate renewal from the Federal Aviation Administration (FAA).
Bell has carried out unspecified modifications to the two remaining test aircraft (FTV-2,-3) following the crash. The flight was resumed on Friday, precisely one year and one day into the July 6 crash last year.
Despite the crash and grounding, Bell remains hopeful of introduction of the 525 next year, a one year delay from the earlier plan. Two more flight test aircraft, which will be in the final production configuration are being build to complete the flight testing on schedule.
Since maiden flight of FTV-1 in 2015, the type has been flown for more than 300 hours.
Powered by two 2,000 shp-class General Electric CT7- 2F1 turboshaft engines, the Relentless is the first commercial helicopter to sport a fly-by-wire flight control system and is equipped with a Garmin G5000H touchscreen avionics.
NTSB is expected to release the final investigation report into the crash in coming months.
Prior to crash, the 525 FTV-1 experienced rotor system vibration and frequency resonance in its airframe, which caused the tail rotor to leave its rotation plane and slice through the nose and tail boom, resulting in-flight break up.
The 525 FTV-1 crashed in Italy, Texas killing its two test pilots. The investigation will be aided by the extensive telemetry data available and reports from the chase Bell 429 pilot.