Gulfstream is calling for operators of G650 and G650ERs that are at least 24 months old to immediately comply with a Rolls-Royce service bulletin involving inspections and lubrication of the high-pressure (HP) compressor variable stator vane (VSV) mechanism. A maintenance and operations (M&O) letters sent to operators late last week said affected aircraft “will be permitted one flight cycle to allow for the relocation of the aircraft” until they are deemed in compliance with the work outlined in the Rolls-Royce Non-Modification Service Bulletin SB-BR700-72-900178 or Gulfstream’s Customer Bulletin 246 (which provides instructions on compliance with the SB).
Last week’s M&O letters followed two incidents involving inflight engine shutdowns that occurred in less than a year. The first occurred in September 2018 and the second in more recent weeks. Follow-up investigations revealed both shutdowns were caused by a high-friction condition within the HP compressor VSV mechanism. “When the high-friction condition is present, excessive torque is required to move the VSV system, resulting in an electronic engine control-commanded shutdown,” Gulfstream said.
After the September event, Rolls-Royce released the service bulletin for inspection and lubrication of the VSV mechanism within 12 months. But after the second event, Gulfstream said, “We have decided it would be prudent to accelerate inspection and lubrication requirements for aircraft that have been in service for 24 months or more, starting from July 2019.”
Gulfstream was working with operators on meeting the requirements. By early this week, the manufacturer estimated that the work had already been accomplished on about 60 percent of the affected fleet of 254 aircraft. Gulfstream and Rolls-Royce field representatives, as well as other trained technicians, can perform the inspections, Gulfstream said. In addition, the inspections can be performed at any Gulfstream service center or center in the Rolls-Royce network.
The manufacturer added that it is continuing to investigate the issue with Rolls-Royce and would provide further communication as appropriate.
Editor's Note: This story has been updated to include both the G650 and G650ER and reflect the amount of work already accomplished.