Ah, thank you gents for reminding me why I left the "heavy metal" aircraft industry.
Down here in the weeds, working on single and 2-seat light aircraft, we routinely design build and certify new light aircraft types within a year, usually with tiny teams. It's not easy, and the people achieving this are very very good at their jobs - but equally importantly they are still working in an environment where it's possible.
The key points to success in this sort of venture are:-
- Having somebody very competent, who understands the whole design build and approve process, in charge.
- Re-using as many existing bits as you can get away with, and never using a new engine in a new airframe.
- A team no bigger than it needs to be.
- Avoid committee decisions. If there's a chief designer - that's what he is. If there's a chief stressman, he has final say and also decides what extra investigation is needed - nobody can overrule them (but they need to be good enough).
- Agree the certification basis with "the authority" (whoever it is) as you go along, never after something has been designed.
So yes, it is possible and there are people who are good enough to do it, even in the UK (to name names: Ivan Shaw, Bill Brooks, Mike Whittaker all have done it).
But, the first casualty of the alien invasion would have to be the "avoid all risks, regardless of the escalating cost" management structure of companies like BAE. Also we need to avoid too-narrow specialists. Ivan, Bill and Mike are all very competent pilots
as well as being designers - certainly none are
just stressmen, pilots, aerodynamicists or what have you. So, if you read their biographies were most of the pioneers at the companies doing this sort of rapid development in the 1930s.
If you want to see how to do it, read
this book , written by Neville Shute, who truly understood the process, on some very big aircraft.
G