  We present results from direct measurements of the $^{27}{\rm Al}(\alpha,n)$
thick target yield from laboratory incident energies $E_{\alpha}\approx$
3$-$5~MeV, performed with the $^{3}$HeBF$_{3}$ Giant Barrel (HeBGB) neutron
detector at the Edwards Accelerator Laboratory. Our measurements have a small
energy cadence in order to address discrepancies and sparseness of thick-target
yield data sets existing for this energy region. We find general agreement with
existing data sets, including yields derived from cross section data, while
resolving a discrepancy between existing thick-target yield data sets for
$E_{\alpha}\approx4-5$~MeV. However, for $E_{\alpha}<3.5$~MeV, our results are
substantially lower than previous thick-target yield data and somewhat larger
than yields calculated from existing cross section data. Our data complete the
energy-range needed for estimates of the $^{27}{\rm Al}(\alpha,n)$ contribution
to neutrino and dark matter detector backgrounds and result in increased
viability of $^{27}{\rm Al}(\alpha,n)$ as a plasma diagnostic tool at fusion
facilities such as the National Ignition Facility.
