Yes, it is the same game engine with many changes and tack-ons.
Even the smallest of details from Air Warrior are still here: ability to shut down a specific engine on a bomber for example (in the original this used to work most of the time to put out a fire if done quickly enough, but this was changed.... explanation given was basically: "to make the fighter pilots happy - get more kills/perks" - it used to be a REAL challenge to take down a bomber, especially a B-17 with all guns manned!!! (which was also disabled... now you can only have 1 gunner aboard.) This was probably a reasonable change though, because pilots abused this by flying low over targets as airbase suppression, which is something real bombers never did.
The orgininal aircraft still have all the very same basic 3D innards (which they dont really need and eat up memory- but they wanted them accurately built for more realism.)
Doubt me if you want

On the ground they elminated the old supply trucks (deuce and a halfs) which were difficult to drive on solid ground and would flip over very easily, and replaced with Jeeps.
I LIKE A LOT OF THE CHANGES...... most of the things done by Dale are exactly right. This change is not good for the game. It will appease the Playstation crowd, likely, but that seems to be the way most changes are headed... quick gratification over patience and a certain respect for realism.
Joe