  An orthogonal array OA(q^{2n-1},q^{2n-2}, q,2) is constructed from the action
of a subset of PGL(n+1,q^2) on some non--degenerate Hermitian varieties in
PG(n,q^2). It is also shown that the rows of this orthogonal array correspond
to some blocks of an affine design, which for q> 2 is a non--classical model of
the affine space AG(2n-1,q).
