The system is not readily adaptable to inverted flying since the entire oil supply will flood the engine.
Dry-sump. The oil supply in this type of system is carried in a tank. A pressure pump circulates the
oil through the engine and scavenger pumps return it to the tank, as shown in figure 3-3.
Turbine engines. Turbine engines use both wet-sump and dry sump systems for lubrication. Each type is
explained in the following paragraphs.
Wet-sump. Wet-sump engines store the lubricating oil in the engine proper, either in the accessory
gearcase, or a sump mounted on the bottom of the accessory case. Figure 3-4 turbine engines.
Dry-Sump. Dry-sump engines store the lubricating oil in a tank mounted on the engine. The
pressure system, as shown in figure 3-5, supplies oil to the accessory drives. The scavenger system returns the oil to the
engine oil tank which usually is mounted on the compressor case. It is connected to the inlet side of the pressure oil
pump and completes the oil flow cycle. A breather system connecting the individual bearing compartments and the oil
tank with the breather pressurizing valve completes the engine lubrication system.
3-4 Change 1