Abstract: There are various costly aircraft IR signature-modelling software packages available in the marketplace that require high computational power. The goal of this paper is to present a cost-effective approach to these expensive options. In a low-fidelity model the whole aircraft body is taken as one IR source, while high-fidelity models aim at taking different parts of the aircraft as different IR sources. In our approach, the aircraft 3D model is divided into different parts such as nose, metallic body, glass canopy and exhaust gas plume and then the radiance of the different parts of the aircraft based on their emissivity and temperature is calculated to represent its high-fidelity IR signature. The model is validated against numerical values and visual thermal images of the aircraft. This personal computer based non-destructive application additionally provides a cost-effective alternative to the field trials/testing of flares in which numerous scenarios can be simulated efficiently and with controlled environmental conditions.