At present the SASE3 undulator beamline of the European XFEL includes 21 planar undulators which generate horizontally polarized radiation in the soft X-ray region between 0.4 and 5.0nm. In order to satisfy the demand to full polarization control it is planned to install four helical undulator segments at the end of the planar SASE3 undulator system. The helical undulator segments will be used as an afterburner, i.e. they will use the micro-bunched electron beam and produce enhanced coherent radiation at a power level comparable to the linear system but with full polarization control. In this contribution the properties of the emitted radiation will be investigated.