Fluid flow metering device for aircraft shaft(s)

An assembly for an aircraft, comprising:

• a first shaft including a first shaft bore and a first shaft end, the first shaft bore projecting axially along an axis into the first shaft from the first shaft end;
• a second shaft including a second shaft bore and a second shaft end, the second shaft bore projecting axially along the axis into the second shaft from the second shaft end;
• and
• a metering device including a device sidewall, a device first end, a device second end, a device bore, a plurality of channels and a plurality of ports, the device sidewall circumscribing the first shaft at the device first end, the device sidewall disposed in the second shaft bore at the device second end, the device bore extending axially along the axis through the metering device between the device first end and the device second end, the plurality of channels arranged circumferentially about the axis and running axially along an inner side of the device sidewall, each of the plurality of channels projecting partially radially into the inner side of the device sidewall from the device bore and axially into the device sidewall from the device second end, the plurality of ports arranged circumferentially about the axis, and each of the plurality of ports projecting radially through the device sidewall,
• wherein the first shaft bore is in fluid communication with the plurality of channels and the plurality of ports.