  The dependence E_h (N_e) of Extensive Air Shower (EAS) hadronic component
energy flux on the number N_e of particles in EAS is investigated in the
primary energy range of the order of 10^{15} - 10^{17} eV. The work was aimed
at checking the existence of irregularities of E_h (N_e)/N_e behavior at these
energies in several independent experiments. The investigation is carried out
using large statistical material obtained at different configurations of
experimental apparatus and under different triggering conditions. The existence
of irregularities of E_h (N_e)/N_e behavior in the region Ne > 2*10^6 is
confirmed. These irregularities have the character of sharp deeps and are
located near the same values of N_e regardless of the experimental material and
selection conditions used. So, at recent stage of research the existence of
these irregularities of E_h (N_e)/N_e behavior in the range of N_e > 2*10^6 may
be regarded as reliably established. This fact supports our earlier conclusion
on the existence of primary cosmic radiation (PCR) nuclei spectra cutoff effect
in the primary energy region 10^{15} - 10^{17} eV.
