US Patent 9739173 Gas turbine lubrication systems

A casing for a fan drive gear system includes a cast body with an upper and a lower portion. The cast body defines an oil inlet and an oil outlet arranged below the oil outlet. An integrally cast oil channel extends between the inlet and outlet for conveying oil from the upper portion of the cast body portion to the lower portion of the cast body for providing a supply of lubrication to the gear system when oil pools in an upper portion of an auxiliary oil reservoir during negative-G flight events.