RPA delivers the comprehensive thermodynamic data library out of the box. This library is mainly based on NASA Glenn thermodynamic database and contains data for both reaction products and reactants (propellant components) such as liquid hydrogen, RP-1, RG-1, Synthine, liquid methane, liquid propane, monomethyl hydrazine (MMH), unsymmetrical dimethyl hydrazine (UDMH), liquid oxygen, nitrogen tetroxide, hydrogen peroxide, and many other.

Still, the user may want to define custom propellant components or even reaction products to solve some special cases.