In this case report, using the Heavy Weight Deflectometer (HWD) deflections collected at National Airport Pavement Test Facility (NAPTF), the elastic moduli of rigid airport pavement layers are evaluated by back-calculation approaches. Based on layered elastic (LE) analysis and iteration procedure, analysing back-calculation results under different HWD drop loads (DLs) and heterogeneous material properties can effectively improve the evaluation accuracy of pavement responses under practical loading conditions. Under different HWD DLs, consistent evaluation of elastic moduli of the PCC slabs and base course was obtained. However, an overestimation for subgrade moduli was found in the back-calculation result of low HWD DLs (50 kN and 100 kN). The subgrade responses need a high DL to be accurately measured. Therefore, a higher drop load (e.g. 150 kN) is recommended for a rigid airport pavement with a stiff PCC slab layer. Furthermore, under different HWD DLs, the back-calculated subgrade moduli of flexible and rigid airport pavements were compatible. The back-calculated subgrade moduli were also consistent with the subgrade moduli estimated by in situ testing. In an indoor experimental environment, consistent subgrade responses of rigid and flexible pavements can be verified by the back-calculation under varied HWD load conditions.