A phenomenological model for the production of "Centauro"-type cosmic-ray events is developed, assuming a nucleus-nucleus interaction in the upper atmosphere. The model is used to estimate, in a selfconsistent way, several thermodynamic and kinematical quantities, characterizing the observed Centauro events. On the basis of this model, we describe a typical "Centauro" event, possibly produced in the fragmentation rapidity of an A + A central collision at & =200A GeV at the BNL Relativistic Heavy Ion Collider. We suggest several characteristic signatures for these events, as well as the possibility of observing "strangelets." PACS number(s1: 96.40. De, 12.38.Mh, 13.85.Tp, 25.75. + r