I think that using fourth and fifth generation to describe aircraft is better, especially when you combine it with production status. For example, both the SU-

I think that using fourth and fifth generation to describe aircraft is better, especially when you combine it with production status. For example, both the SU-27 and F-16 are clearly fourth generation, and both currently in production. Same with the F-15. They may have origins that are quite a long time ago, but they're still effective aircraft in many scenarios. Fifth generation would be F-22, F-35, J-20, FC-31, and if you want to be generous, the Su-57. Stealth is the primary attribute, though supercruise is sometimes considered a key attribute as well.