System and method for reducing wear in a gearbox during a wash event of a gas turbine engine

A system for reducing wear during a wash of a gas turbine engine, the system comprising:

• an accessory gearbox;
• a transfer gearbox drivingly coupled to the accessory gearbox;
• and
• a lubrication system fluidly coupled to the accessory gearbox and the transfer gearbox, the lubrication system comprising:
• a lubricant reservoir;
• a lube and scavenge system;
• a supply circuit having an inlet supply line extending from the lubrication reservoir to the lube and scavenge system and an outlet supply line extending from the lube and scavenge system to the accessory gearbox and the transfer gearbox;
• a return circuit to return the lubricant from the accessory gearbox and the transfer gearbox to the lubricant reservoir;
• one or more heat exchangers disposed in thermal communication on the outlet supply line;
• and
• a supply-side bypass line extending from the outlet supply line upstream of the one or more heat exchangers to the outlet supply line downstream of the one or more heat exchangers.

A method for reducing wear during a wash of a gas turbine engine, the method comprising:

• rotating one or more shafts of the gas turbine engine connected to an accessory gearbox and a transfer gearbox;
• actuating one or more valves fluidly connected to a return circuit of a lubrication system fluidly connected to the accessory gearbox and the transfer gearbox to a closed position to prevent the lubricant from leaving the accessory gearbox and the transfer gearbox;
• and
• providing lubricant to the accessory gearbox and the transfer gearbox at least partially via a bypass line of the lubrication system.