the present device system and method said internal container 4 is arranged inside said external container 15 and this to be able to be moved longitudinally in the latter with the help of sliding means 6 comprising for example rails fastened on the external container 15 cooperating with means being integral with the internal container 4 more precisely said internal container 4 is able to be brought with the help of said sliding means 6 from a front position p 1 represented on fig1 to a rear position p 2 represented on fig2 in the direction illustrated by an arrow f 1 and from such position p 2 again to the position p 1 in the direction illustrated by an arrow f 2 such positions p 1 and p 2 correspond respectively to a carrying position p 1 in which the internal container 4 is completely located inside the external container 15 and thus inside the hold 2 and an off loading position p 2 in which the internal container 4 is longitudinally offset toward the rear of the aircraft ac with respect to the first position p 1 so that a part 7 of said internal container 4 is then located outside said external container 15 and outside the transport airplane ac through an opening 8 at the rear of the hold 2 so as the system 1 according to the present device system and method comprises a single external container 15 being equipped with all the means being necessary for the carrying and the off loading particularly one or more internal containers 4 and associated sliding means 6 it is sufficient to install such an external container 15 in the airplane ac to be able to implement the present device system and method consequently a system.