A gas turbine engine in which a compressor, a combustor, and a turbine are arranged so as to be lined up along a rotating shaft, the gas turbine engine comprising: a casing that accommodates the compressor, the combustor, and the turbine; fuel pump units that are arranged at an outside of the casing, and are connected in parallel; and a fuel supply pipe that collects fuel discharged from the fuel pump units and supplies the fuel to the combustor, wherein: the fuel supply pipe includes a common pipe extending toward the combustor and branch pipes extending from the common pipe toward an upstream side; the branch pipes are connected to discharge ports of the fuel pump units, characterized in that: the fuel pump units are lined up in a circumferential direction along an outer peripheral surface of the casing; each of the fuel pump units has an elongated shape extending in one direction; the fuel pump units are side-by-side such that a longitudinal direction of each fuel pump unit is parallel to a rotation axis of the rotating shaft; each of the fuel pump units includes a displacement pump including a rotation axis extending along the longitudinal direction and an electric motor that is located adjacent to the displacement pump in a direction along the rotation axis of the displacement pump and drives the displacement pump; the discharge port of the displacement pump is located at an opposite side of the electric motor in the direction along the rotation axis of the displacement pump; the fuel supply pipe is arranged at an opposite side of the electric motors across the displacement pumps of the fuel pump units. the gas turbine engine comprising: a casing that accommodates the compressor, the combustor, and the turbine; fuel pump units that are arranged at an outside of the casing, and are connected in parallel; and a fuel supply pipe that collects fuel discharged from the fuel pump units and supplies the fuel to the combustor, wherein: a casing that accommodates the compressor, the combustor, and the turbine; fuel pump units that are arranged at an outside of the casing, and are connected in parallel; and a fuel supply pipe that collects fuel discharged from the fuel pump units and supplies the fuel to the combustor, wherein: the fuel supply pipe includes a common pipe extending toward the combustor and branch pipes extending from the common pipe toward an upstream side; a common pipe extending toward the combustor and branch pipes extending from the common pipe toward an upstream side; the branch pipes are connected to discharge ports of the fuel pump units, characterized in that: the fuel pump units are lined up in a circumferential direction along an outer peripheral surface of the casing; each of the fuel pump units has an elongated shape extending in one direction; the fuel pump units are side-by-side such that a longitudinal direction of each fuel pump unit is parallel to a rotation axis of the rotating shaft; each of the fuel pump units includes a displacement pump including a rotation axis extending along the longitudinal direction and an electric motor that is located adjacent to the displacement pump in a direction along the rotation axis of the displacement pump and drives the displacement pump; the discharge port of the displacement pump is located at an opposite side of the electric motor in the direction along the rotation axis of the displacement pump; the fuel supply pipe is arranged at an opposite side of the electric motors across the displacement pumps of the fuel pump units. the fuel pump units are lined up in a circumferential direction along an outer peripheral surface of the casing; each of the fuel pump units has an elongated shape extending in one direction; the fuel pump units are side-by-side such that a longitudinal direction of each fuel pump unit is parallel to a rotation axis of the rotating shaft; each of the fuel pump units includes a displacement pump including a rotation axis extending along the longitudinal direction and an electric motor that is located adjacent to the displacement pump in a direction along the rotation axis of the displacement pump and drives the displacement pump; a displacement pump including a rotation axis extending along the longitudinal direction and an electric motor that is located adjacent to the displacement pump in a direction along the rotation axis of the displacement pump and drives the displacement pump; the discharge port of the displacement pump is located at an opposite side of the electric motor in the direction along the rotation axis of the displacement pump; the fuel supply pipe is arranged at an opposite side of the electric motors across the displacement pumps of the fuel pump units.