A methodological approach for statistical evaluation of aircraft infrared signature

Existing computer simulations of aircraft infrared signature do not account for the dispersion induced by uncertainty on input data such as aspect angles and meteorological conditions. As a result, they are of little use to estimate the detection performance of optronics systems: in that case, the scenario encompasses a lot of possible situations, which must indeed be addressed, but cannot be singly simulated. In this paper, a methodological approach aimed at predicting simulated infrared signature dispersion of poorly known aircraft is proposed. It is based on a sensitivity analysis, which identifies inputs that have negligible influence on the computed infrared signature and can be set at a constant value, and on a quasi-Monte Carlo survey of the code output dispersion. This method is emphasized in a typical scenario, namely a daylight air-to-ground full-frontal attack by a generic combat aircraft flying at low altitude, and gives a satisfactory estimation of the infrared signature dispersion with less than 10,000 samples.