The flight conditions chosen for the European supersonic transport aircraft are very severe for the structural materials. As for Concorde, the speed should be up to Mach 2.05, but should last four times as long.

Creep strength then becomes critical. Deformation is limited to 0.1 percent at 130°C under an external stress of 1500 atmospheres for 60,000 flight hours. Modern computation techniques are used to simulate dislocation movement and thereby help control creep.

It is also attempted to improve the resistance to crack propagation. The simulations are aimed at understanding these mechanisms, for the purpose of choosing the alloy microstructure so that the cracks propagate as slowly as possible.