Fuel leakage protection system for gas turbine engine

A fuel leakage protection system (32) for a gas turbine engine (12) having a fuel system (30) that has a plurality of circumferentially spaced fuel nozzles (34) that are equally circumferentially spaced around a combustor section (24) of a gas turbine engine, a plurality of fuel tubes (36) having ends that are connected to the fuel nozzles by fuel supply fittings (62, 64) for delivering fuel to the fuel nozzles (34) individually, a pair of generally semi-circular fuel manifolds (40) that are located aft of the fuel nozzles (34) and that are connected to the fuel tubes (36) for delivering fuel to the fuel tubes (36), each of the fuel manifolds having an L-shaped fitting (45) having ends at one end, and a branch manifold (44) having ends that is connected to the L-shaped fittings (45) of the fuel manifolds (40) by fuel supply fittings (80, 82) having ends for delivering fuel to the fuel manifolds (40) via the L-shaped fittings (45), comprising:

• collar assemblies (38) encapsulating respective fuel supply fittings (62, 64) connecting the end of each fuel tube (36) and a respective end of its associated fuel nozzle (34) for trapping any leakage fuel from the fuel supply fittings,
• collar assemblies (46) encapsulating respective fuel supply fittings (80, 82) connecting the ends of the branch manifold (44) and the respective connecting ends of the L-shaped fittings (45) for trapping any leakage fuel from the fuel supply fittings,
• a fuel collection manifold (48) that is located aft of the two semi-circular fuel supply manifolds (40);
• the fuel collection manifold (48) collecting leakage fuel from the collar assemblies (38) via a plurality of fuel return tubes (49) that are connected to the manifold (48) by T-fittings (50) at one end and fluidly connected to each one of the collar assemblies (38) individually at the other end;
• the fuel collection manifold (48) also collecting leakage fuel from the collar assemblies (46) via a plurality of fuel return tubes (52) having ends that are connected to the manifold (48) at one end by two of the T-fittings (50) that have double inlets and fluidly connected to each one of the collar assemblies (46) individually at the other end;
• and
• the fuel collection manifold (48) also having a Y-fitting (54) at the bottom that fluidly connects the fuel collection manifold (48) to an evacuation line (56) that leads to a collector (58) that is located further aft of the combustor section (24).