If you've been gone two years, the time that has passed has given us the B-24, the T34, the Ki84, the P47N, the P-38J, the spitVIII, the SpitXVI, the 109G14, the Firefly Vc, and those are just the NEW planes. We've had many existing planes heavily modified.
Not counting the ENTIRE ariflow code set, changing how all planes handled, from the 109s to the corsairs to the p51s to the 190s.
If you say "nothing new" then I cry "BS!"