Greetings Ray cosmic
In fact it is very simple, Aviation industry can only use proven technology, and proven technology is technology on which ZILLIONS of applications of all sorts have been run, and it is a technology with no hidden snags, so the only candidate can only be an OLD TECHNOLOGY.
if you consider the time scale it is just fascinating, at project lunch technology selection digs into existing and the winer is a 10 years old CPU, then comes developpement taking 5 years (CPU is already 15 years old tech) then your company gets its first aircraft delivery (1 to 2 year after Roll Out) guess what it 17 years old
but the worst is to come, how to manage obsolescence
