Abstract: A system for reducing oil usage from a sump in a gas turbine engine. Two sources of oil usage, which usage includes leakage and consumption, have been identified: (1) during idle, leakage of oil from an oil sump through seals and (2) during high-power operation, consumption of oil entrained in vent air exiting from the sump. At idle, the invention reduces pressure in the sump, to thereby increase airflow across the seals into the sump, to inhibit the oil leakage across the seals. At high power operation, the pressure reduction is terminated, but flow exiting the vent is artificially restricted.

Abstract: A method facilitates assembling a gas turbine engine that includes an oil supply and scavenge system, wherein the oil supply and scavenge system includes at least one sump cavity that includes a first scavenge port and a second scavenge port, a first oil pump and a second oil pump such that the first oil pump is in flow communication with and receives scavenge oil from the first scavenge port and the second oil pump is in flow communication with and receives scavenge oil from the second scavenge port. In addition, an oil supply source is coupled in flow communication with the first and second oil pumps.