Reduction gear assembly and a gas turbine engine

A gas turbine engine comprising:

• a core engine;
• a rotor having a plurality of radially outwardly extending rotor blades secured thereto;
• shaft means for mounting the rotor;
• a reduction gear assembly interconnecting the rotor and core engine, whereby the core engine is arranged to drive the rotor via the shaft means and the reduction gear assembly;
• a source of lubricant arranged to supply lubricant to the reduction gear assembly;
• and annular lubricant collecting member positioned coaxially around the reduction gear assembly to collect lubricant leaving the reduction gear assembly, whereby the annular lubricant collecting member is driven by the reduction gear assembly;
• at least one lubricant scoop relatively rotatable with respect to and arranged to collect lubricant from a trough adjacent to an inner surface of the annular lubricant collecting member, whereby said at least one lubricant scoop is arranged to return lubricant to the lubricant source;
• and valve means arranged to control the flow of lubricant from the lubricant scoop, whereby in normal operation the valve means allows the return flow of lubricant from the lubricant scoop to the lubricant source, and in the event of at least a reduction of lubricant supply from the lubricant source to the reduction gear assembly, the valve means prevents the return flow of lubricant from the lubricant scoop to the lubricant source and interconnects the lubricant scoop to the lubricant source and the reduction gear assembly to allow the lubricant from the lubricant scoop to return to the reduction gear assembly to form a recirculating lubricant system.