A nozzle is described for downwardly directing air from an air intake of a fiber draw unit into a longitudinal channel of the fiber draw unit for forming spunbond polymeric fibers. The nozzle includes an upper eductor connected to the fiber draw unit and a lower eductor adjustably connected to the fiber draw unit and below the upper eductor. The nozzle includes a nozzle cavity that narrows from a nozzle inlet to a nozzle outlet and includes a downward turn of 90 degrees or less. Air directed through the nozzle outlet flows in a direction parallel to a wall of the longitudinal channel.