Foamed propellants based on polymer bonded nitramines show high conversion rates due to their porous structure. The properties of the material can be varied in a wide range by using different explosive fillers, energetic binders and porous structures. Foamed propellants with high energy content and variable burning and material characteristics can be formulated. Due to this flexibility, these propellants can be adjusted to manifold applications. The burning characteristics of these porous charges show specific differences compared to standard gun propellants, e.g. the mass conversion rates are essentially above those obtained by combustion of compact materials. In addition, the burning behavior of foamed propellants depending on pressure deviates from that expected by a straightforward use of Vieille's law. This paper presents an overview on investigations carried out in the field of foamed propellants at Fraunhofer ICT concerning thermodynamical calculations, studies on burning behavior and vulnerability.