The pilot of an aircraft is sometimes compelled to proceed to an emergency landing. According to the reasons and the circumstances, secured landing procedures are imposed to him. For instance he can have to land "wheels up".

During such a maneuver, the aircraft touches down at low vertical speed, and ends its flight sliding on the ground. The contact area defined by the procedure is located at the rear cargo part of the aircraft.

In order to study the behaviour of aircrafts in such configurations and to include crash certification requirements in the design process, industrials use powerful finite element tools and computers. These tools make it possible to take into account in the numerical models, at different scale levels, a large pannel of parameters which eventually influence the structural behaviour of the aircraft (soil, materials, assemblies, ...).