The reaction Al(P-2(J)) + O-2(X(3) Sigma(g)(-)) --> AlO(X(2) Sigma(+)) + O(P-3(J)), Delta epsilon(0) = -0.145 eV, is reinvestigated using combined pulsed lasers and pulsed, crossed, supersonic molecular beams. The relative reactive cross section is found to decrease within the sampled relative translational energy domain epsilon(tr) = 0.041-0.42 eV. The observed complex dependence reveals a shift from covalent to ionic in the character of the interaction potential experienced by the reactants with increasing collision energy. The variation of the thermal rate constant calculated from the excitation function is in excellent agreement with recent kinetic measurements of Garland performed in the temperature range 298-1083 K. Decrease of the rate constant at higher temperatures is predicted by the analytical expression k(T) = 0.66 X 10(-10) T-0.2/{1 + T/2100}(1.7) cm(3) molecule(-1) s(-1).