Love the free NASA books. Here's another on the lifting bodies: https://ntrs.nasa.gov/api/citations/19980169231/downloads/19...

Definitely a Grumman when it was built.

FWIW, my introduction to this unusual forward swept wing style aircraft was in Jane's ATF simulation game for the PC back in the mid-90s as a kid and they definitely called it the Grumman X-29. I have no idea how accurate the flight physics were, but boy that was a fun aircraft to fly in the game. I scoffed at the mere concept of having to worry about AOA!

At the time the materials they were using were kind of experimental in the use case. Likely materials science, and definitely computing power have advanced to make the design viable in an operational vehicle.

The program didn't get far enough to determine definitively if it was worthwhile for fighter applications -- the aircraft wasn't designed for that level of maneuverability. It was about learning what they could do at the limit of what was known then about composites, unconventional aerodynamics, and flight control law development.

Part of the genius in this project was they proved you could actually produce a wing out of composites effectively tailored to resist upward (or downward) wing deflection with a counteracting downward (or upward) twist on the leading edge, so despite aggressive maneuvering the wing would not find itself in a self-reinforcing loop of increasing load that would lead to structural failure.

Therefore, the wings wouldn't twist and buckle.

The math said it was possible, but history is littered with clever composite designs that can't actually be manufactured to the required tolerances, or that change shape after coming out of the mold, or that can't be pulled out of a mold without breaking the part or the mold or both.