Abstract: An aircraft fuel pump (10) capable of running dry for extended periods of time without sustaining damage includes a housing (12). The housing is divided into a first fluid chamber (31), and a second fluid chamber (73). An impeller (26) is mounted for rotational movement in the first chamber. The impeller is mounted in connection with an armature (76) housed within the second chamber. A fluid passage (38) connects the first and second chambers. A check valve (40) is positioned at an upper end of the passageway in the second chamber. The housing also includes a fuel inlet (18) in communication with the first chamber, a fluid outlet (71) from the second chamber and a pump discharge (32) from which fuel is supplied to the remainder of an aircraft fuel system. In operation fluid from the tank fills the inlet and is moved upward by the action of the impeller.

Abstract: A two-staged vapor separating and metering fuel pump for an aircraft includes a housing (12) divided into a liquid ring section, a metering section and a motor section. Vapor-laden fuel enters the liquid ring section through a fuel inlet opening (14) and enters a liquid ring chamber (36) wherein vapor is separated from the fuel by the rotary action of a liquid ring impeller (44). The separated vapor is discharged from the housing through a vapor outlet opening (18). Vapor-free liquid from the liquid ring section is delivered to a metering chamber (86). The action of a metering rotor (72) in the metering chamber causes fuel to be discharged from the metering section at a flow rate proportional to the rotational speed of the metering rotor. The metering section discharges fuel from a pair or outlet ports (94) into a cavity (114) in the motor section. The motor section includes an armature (104) which is connected to a shaft (46) on which the metering and liquid ring impellers are mounted.