[en] In a series of balloon flights, the intensity of stopping heavy nuclei of cosmic radiation at a height of 22 km was measured with plastic detectors. The measured charge spectra, compared to the charge spectrum at the boundary of the atmosphere are changed by fragmentation. Nuclei with odd charge numbers, which are rare in the primary spectrum, are about as frequent in the atmosphere as the nuclei with even charge numbers. Intensities could be calculated from the primary spectra considering the energy loss and the fragmentation which agree with our own measured results and the measurements of other authors in an energy range of up to a few GeV/nucl. The parameters for fragmentation in air with which this agrees are similar to those for the fragmentation with collision on light nuclei in emulsion. The solar modulation and the radiation load due to heavy nuclei are discussed. (orig./LH)