A new SCT requires new materials to become viable – at least a new Concorde-type SCT; an Oblique Flying Wing (OFW) may possibly be using nowaday’s materials. But before new materials can be counted on in aircraft design, all relevant material properties must be well known And not only the matcnul properties itself, but also the technologies to design for them, work with them, form them, join them with other parts of the same material or with the other materials used
with them. When all this is known, we need the technologies and procedures to build and assemble large aircraft parts using these materials, which usually requires another set of manufacturing technologies And last not least, we need certification rules and procedures applied to these new materials
All these processes and the relevant data must be proven to be reliable and must be approved and certified by the authorities. This requires a long time, especially when fatigue related data are requested.
Before introducing a new material in aircraft design, it must be highly probable, that certification of the material and the related processes will be achieved timely. It’ this is not certain. a fall back solution must be developed (and possibly manufactured» in parallel! This is very expensive, consumes many resources and should be avoided whenever possible, but it can become necessary for risk minimisation in a light time schedule.