|"But the Gripen NG is just a paper airplane!"|
The Gripen E/F is a variant of the existing JAS-39 Gripen. Nothing more. Very little is actually changed on the airframe itself. Externally, the only visible changes are a slightly modified wing, additional weapon pylons, repositioned main landing gear, and the addition of a IRST sensor at the base of the canopy.
It is the parts you can't see that undergo most of the changes. The most important change is the switch to the GE F414G engine for additional power. Repositioning the main landing gear frees up space for an additional 40% more fuel. The rest is mainly modernized avionics and other systems.
|Gripen A cockpit.|
|Gripen C cockpit.|
|Gripen E cockpit.|
The cockpit shows a continued evolution as well. Much like the F-35, Saab plans to remove the traditional heads-up-display (HUD) in favor of a helmet mounted display (HMD). Unlike the F-35, however, the Gripen's HMD has already been in service for the last 5 years.
|The Gripen F Demonstrator: Flying now.|
The Gripen E/Fs are not a "fresh off the drawing board" aircraft. In fact, Sweden has made plans to upgrade its existing Gripen fleet to the E/F standard, much the same as Canada upgraded its CF-18 fleet a few years ago.
|F-35 variant comparison.|
The changes made to the Gripen to upgrade it to E/F standard are indeed less extensive than the differences between F-35 variants. The F-35C uses completely different wings and tails, while much of the F-35B's fueselage is unique. It is highly unlikely that a F-35A would be converted to the F-35B standard, and vise-versa. The Gripen E/F upgrades are also nowhere near that of the differences between the F/A-18C/D Hornet and the F/A-18E/F Super Hornet, which is almost an entirely different aircraft.
|Hornet vs Super Hornet.|
In effect, almost all of the aircraft being marketed as Canada's next fighter are at similar stages as the Gripen E/F. The F-35A is still in testing, with years of development still to go. The "Tranche 3" Eurofighter Typhoon is just beginning production, and the "International Roadmap" (aka Block 3) Super Hornet has yet to be flown.
So, yes. The Gripen E/F technically does not exist yet as a ready-for-combat fighter. Then again, neither does the Tranche 3 Typhoon, F-35, or the "International Roadmap" Super Hornet. The upgrades for the Gripen E/F are relatively modest however, and present little risk.
So is the Gripen E/F a "paper airplane"? It is in this video.