The concept of Lack Of Knowledge (LOK), first introduced in [1,2], combines probabilities with interval analysis [3]. The basic principle consists in globalizing the various sources of errors on the substructure level using a scalar internal variable, called the LOK variable, defined over an interval whose upper and lower bounds follow probabilistic laws. From these basic LOKs, we can derive for the whole structure the effective LOK for a quantity of interest a, resulting in an interval with stochastic bounds that we can compare with experimental values. In [4], we presented the first results of a strategy of using additional experimental information to reduce the LOKs, starting from an initial overestimated LOK level, given by experience or a priori knowledge. This paper is focused on the reduction of the LOKs of a actual, industrial structure from the European Aeronautic Defence and Space company; this real-case study shows the effectiveness of the strategy of reduction used.