In order to achieve future noise targets and develop aircraft noise prediction capabilities, this paper proposes a calculation framework for core engine airworthiness noise. Based on the Peart & Dunn model and SAE-GE model, the far-field mean-square acoustic pressure in 1/3-octave bands for turbine and combustion are estimated respectively; then the integrated core engine noise is corrected and converted into the effective perceived noise level which is required by the airworthiness regulations. Taking a certain engine as an example, the relative error of the algorithm is verified as about 2% by comparing the estimated value of the algorithm with the official measured value, showing that it can be used for fast-calculating the approaching core engine noise, so as to give convenience for the manufacturer to control the aeroengine core noise to meet the airworthiness requirements at the design stage. Meanwhile, it provides a new idea for determining the start point of the approaching noise airworthiness certification test in advance.