Bell Helicopter has started final assembly of the first four production examples of the 525 Relentless as it works to keep the programme on track despite the fatal loss of its initial flight-test aircraft in July.

Flight tests of the super-medium-class helicopter remain suspended in the wake of the 6 July accident in which two pilots were killed after the helicopter broke up during high-speed manoeuvres.

However, the airframer has continued to perform ground tests – including component, system and structural evaluations – on the GE Aviation CT7-powered helicopter.

And the initial batch of customer aircraft are on the production line, along with the remaining two flight-test prototypes which should arrive in 2017.

Larry Thimmesch, vice-president of 525 sales and business development, says that Bell's return-to-flight team is “working very closely” with investigators from the US National Transportation Safety Board: “They are preparing everything that has to happen so when we return to flight we are safe and have done everything we need to do.

“There is a tremendous amount of activity on the programme to get ready for that,” he says.

Thimmesch offers no timeline for a return to flight, however, and declines to speculate on the cause of the accident, noting that both are matters for the NTSB.

But with the flight-test aircraft so heavily instrumented it is likely that Bell and the NTSB already have a strong understanding of the events leading up to the incident.

Thimmesch also refrains from speculating on any revisions to the certification date for the fly-by-wire 525, with the airframer having previously hinted that this may push into 2018.

“Once we are back flying we will be very clear about what the certification schedule looks like,” he says.

Source: FlightGlobal.com