Gearbox fix fails to solve cracks behind S-92 crash

摘要

Us and European regulators say a new and improved main gearbox mounting structure for the Sikorsky S-92A continues to exhibit the cracking problems that plagued an earlier design. In a new amendment to a 2009 airworthiness directive that requires operators of S-92A heavylift twin-engined helicopters to inspect the mounting feet every 10h, both the Federal Aviation Administration and European Aviation Safety Agency have added the inspection requirement to a modified main gearbox housing that was designed to eliminate the cracking problem.