The fuselage is S-3 Viking
Joined-Wing Integrated Structures Flight Demonstration - Sweep wings aft and bring an elongated tail forward to meet the wings at the tip, and the open diamond-shaped lifting surfaces are the hallmark of the Joined-Wing project. The fuselage of an S-3 Viking aircraft would test the joined wings. The configuration is envisioned as a way to use powerful radars in the wings of smaller airframes for improved aircraft performance and radar effectiveness. NASA's Langley Research Center leads a team that includes Dryden, Boeing Phantom Works, Naval Air Systems Command, and the U.S. Air Force Research Lab.