The temperature distribution of the exposed rear fuselage of fighter aircraft, which is necessary for estimating passively emitted infrared signature levels, is predicted. Hot combustion gases flowing through the gas-turbine engine and aerodynamic heating of the rear fuselage at high freestream Mach numbers are the two heat sources. Turbulent forced convection and radiation are the dominant heat-transfer modes, and hence two thermal models are developed: only turbulent forced convection, and combined turbulent forced convection and radiation. Variation in transport and thermophysical properties of fluids is also modeled. Gas-dynamic equations are used to obtain local flow parameters, considering the role of friction, heat transfer, and area variation. A radiation-shape-factor analysis for the complete layout is presented that accounts for mutual, partial, or complete visibility of emitter and receiver elements. A closed-form solution for shape factors between ring elements is derived for the annulus. The error in temperature estimation by neglecting parameters such as aerodynamic heating, variation in transport, and thermophysical and local-flow properties of fluid is found to be significant. We conclude with a discussion of the role of altitude and flight Mach number.