A drive unit (16) for an aircraft running gear (2) having at least a first wheel (4) and a second wheel (6) on a common wheel axis (A), wherein the drive unit (16) is drivingly coupleable to at least one of the first and second wheels (4, 6), is characterized in that the drive unit (16) comprises at least one power output assembly (122, 124) for driving at least one of the first and second wheels (4, 6), with each of the at least one power output assembly (122, 124) comprising a power transmission chain (136) selectively engageable with a sprocket element (108, 110) coupled to one of the first and second wheels (4, 6).