Certification of the redesigned bevel gear vertical shaft for the Airbus Helicopters EC225 is expected towards the end of March 2014 or in early April as the manufacturer looks for a swift resolution to the problems that have afflicted the type since May 2012.

Assuming approval from EASA occurs as planned, then retrofit of the component to the global fleet of EC225s and military EC725s should begin in the third quarter, says Jean-Brice Dumont, group chief technical officer at the Marignane-headquartered airframer.

The majority of EC225s were grounded in October 2012 following a pair of North Sea ditchings involving the type. These were found to have been caused by cracks in the shaft precipitated by "active corrosion" of the component.

Airbus Helicopters introduced an interim fix for the problem in mid-2013 and Dumont says that "more than 90%" of the fleet has now returned to full operational status.

Dumont says the revised shaft has yet to fly but has "been corroded, tortured and cracked" in its test facilities, and subjected to loads 1.4 times larger than those required for certification.

While currently unable to quantify how much the problem has cost Airbus Helicopters – through lost sales and the engineering effort required to resolve the issue – Dumont says it has undoubtedly "hurt the company" and also resulted in a "clear loss of confidence" among operators.

However, he believes the manufacturer's "transparency" in its subsequent response has slowly won back that trust, although he notes it remains "very fragile".

As part of its communications effort, around 40 representatives from the oil and gas industry attended a mid-January meeting in Marignane, where the next steps were explained.

Source: FlightGlobal.com