Different variants have same empty weight

[pokmnnjiuhb]

I just noticed that both Ka-50 II and Ka-50 III have same empty weight (8030kg), even after changing to version 2011 in ka-50 III, which the pylon and additional sensors are removed, it still shows the same empty weight.

How could different Ka-50s have exact same weight? In other modules, such as UH-1 and Mi24, the weight decreases after removing any of the parts on the helicopter such as IR suppressors.