Airborne electronics are designed to operate over a wide spectrum of flight conditions. This is much unlike ground-based electronics which operate at a constant altitude and within limited operating regimes. This makes airborne electronics far more challenging to design and analyze, especially from an aerothermal standpoint. With the modernization of the aviation industry, the LRUs of airborne electronics are continuing to miniaturize resulting in a manifold increment in their thermal flux. There is thus an ever-increasing need for performing thermal analysis of the electronics packages in-situ with the overall design process. The conventional analytical and computational thermal analysis methods for electronics are complex and highly recursive. This makes the early-on assessment of thermal parameters a major problem to reckon with during the conceptual design phase. In this paper, a novel approach for preliminary thermal analysis of airborne electronics has been proposed for the evaluation of temperature variations within a wide range of flight regimes. The Minimal Input Dimensionless Empirical-Corrector (MIDEC) method is developed that uses minimum fundamental operating and thermal variables to perform an initial assessment of temperature variations on aircraft surfaces, and housing electronics LRUs at different flight regimes. The results obtained from the MIDEC approach are assessed for a sample case scenario of electronics LRU installed on an airborne platform. Validation and verification of results exhibit a high degree of conformance between the MIDEC estimated results and those obtained through analytical and high-speed computational methods