  The bremsstrahlung flux-averaged cross-sections $\langle{\sigma(E_{\rm{\gamma
max}})}\rangle$ and the cross-sections per equivalent photon
$\langle{\sigma(E_{\rm{\gamma max}})_{\rm{Q}}}\rangle$ were first measured for
the photonuclear multichannel reaction
${^{27}\!\rm{Al}}(\gamma,\textit{x})^{22}\rm{Na}$ at end-point bremsstrahlung
gamma energies ranging from 35 MeV to 95 MeV. The experiments were performed
with the beam from the NSC KIPT electron linear accelerator LUE-40 with the use
of the $\gamma$-activation technique. The bremsstrahlung quantum flux was
calculated with the program GEANT4.9.2 and, in addition, was monitored by means
of the $^{100}\rm{Mo}(\gamma,n)^{99}\rm{Mo}$ reaction. The flux-averaged
cross-sections were calculated using the partial cross-section $\sigma(E)$
values computed with the TALYS1.95 code for different level density models.
Consideration is given to special features of calculating the cross-sections
$\langle{\sigma(E_{\rm{\gamma max}})}\rangle$ and $\langle{\sigma(E_{\rm{\gamma
max}})_{\rm{Q}}}\rangle$ for the case of the final nucleus $^{22}\rm{Na}$
production in the $^{27}\!\rm{Al}$ photodisintegration reaction via several
partial channels $\textit{x}$: $\rm{n}\alpha + dt + npt + 2n{^{3}\rm{He}} + n2d
+ 2npd + 2p3n$.
