Structural and thermal analysis of integrated thermal protection systems with C/SiC composite cellular core sandwich panels

•The devised ITPS integrates light weight and high service temperature up to 1600 °C.•The critical relative density of the failure models in the ITPS is identified.•The effective thermal conductivity of the ITPS is derived and numerical verified.•Preliminary sizing analysis identifies the acceptable dimensions of the ITPS.•The ITPS incorporates much low areal density ρa and high effective specific heat Ceff.