A propulsion system for an aircraft comprising: at least two fans (22, 24; 122, 124; 208, 210), each fan (22...210) having a fan drive shaft (56; 156); at least two turboshaft gas turbine engines (26, 28; 126, 128; 202, 204) for driving said at least two fans (22...210), each turboshaft engine (26...204) driving a respective output shaft (36; 136) which drives a respective gear (38; 138) to, in turn, drive a respective gear (40; 140) on a respective first intermediate shaft (41, 42; 141; 206; 207) extending from said turboshaft gas turbine engine (26...204) in a rearward direction toward a respective intermediate fan drive shaft (50; 150), each intermediate fan drive shaft (50; 150) driving a respective one of said fan drive shafts (56; 156), each first intermediate shaft (41...207) extending parallel to an axis of rotation of the fans (22...210), said first intermediate shafts (41...207) being concentric, wherein said first intermediate shafts (41...207) each extend to a respective output gear (46; 146) which engages a respective gear (48; 148) on said intermediate fan drive shafts (50; 150), with said output gear (46; 146) on one of said first intermediate drive shafts (41...207) extending to a position spaced rearwardly relative to said output gear (46; 146) on a second of said first intermediate shafts (41... 207); wherein: each first intermediate shaft (41...207) extends over a distance that is greater in an axial dimension defined between said turboshaft gas turbine engine (26...204) and a respective fan (22...210) than in a width dimension defined between said at least two fans (22...210); and each intermediate fan drive shaft (50; 150) extends for a greater distance in the width dimension than in said axial direction and each fan drive shaft (56; 156) extends for a greater distance in said axial direction than in said width direction; characterised in that: each output shaft (36; 136) extends from a forward end of the respective turboshaft engine (26...204). at least two fans (22, 24; 122, 124; 208, 210), each fan (22...210) having a fan drive shaft (56; 156); at least two turboshaft gas turbine engines (26, 28; 126, 128; 202, 204) for driving said at least two fans (22...210), each turboshaft engine (26...204) driving a respective output shaft (36; 136) which drives a respective gear (38; 138) to, in turn, drive a respective gear (40; 140) on a respective first intermediate shaft (41, 42; 141; 206; 207) extending from said turboshaft gas turbine engine (26...204) in a rearward direction toward a respective intermediate fan drive shaft (50; 150), each intermediate fan drive shaft (50; 150) driving a respective one of said fan drive shafts (56; 156), each first intermediate shaft (41...207) extending parallel to an axis of rotation of the fans (22...210), said first intermediate shafts (41...207) being concentric, wherein said first intermediate shafts (41...207) each extend to a respective output gear (46; 146) which engages a respective gear (48; 148) on said intermediate fan drive shafts (50; 150), with said output gear (46; 146) on one of said first intermediate drive shafts (41...207) extending to a position spaced rearwardly relative to said output gear (46; 146) on a second of said first intermediate shafts (41... 207); wherein: each first intermediate shaft (41...207) extends over a distance that is greater in an axial dimension defined between said turboshaft gas turbine engine (26...204) and a respective fan (22...210) than in a width dimension defined between said at least two fans (22...210); and each intermediate fan drive shaft (50; 150) extends for a greater distance in the width dimension than in said axial direction and each fan drive shaft (56; 156) extends for a greater distance in said axial direction than in said width direction; characterised in that: each output shaft (36; 136) extends from a forward end of the respective turboshaft engine (26...204). each first intermediate shaft (41...207) extends over a distance that is greater in an axial dimension defined between said turboshaft gas turbine engine (26...204) and a respective fan (22...210) than in a width dimension defined between said at least two fans (22...210); and each intermediate fan drive shaft (50; 150) extends for a greater distance in the width dimension than in said axial direction and each fan drive shaft (56; 156) extends for a greater distance in said axial direction than in said width direction; characterised in that: each output shaft (36; 136) extends from a forward end of the respective turboshaft engine (26...204).