Nova X-35

The Nova X-35 is an experimental unmanned hypersonic aircraft. The X-35 set speed records in 2023, breaking the X-15's record, and is the first aircraft to have a turbine-based combine cycle system for propulsion. The X-35's highest speed, 17,260 miles per hour (27,780 km/h; 7,720 m/s) was achieved on 22 December 2023 shortly before the aircraft disintegrated from aerodynamic heating.

At the time, the X-35 was the only known hypersonic aircraft to not be air launched and instead take off from a runway on its own. This was achieved by its Turbine-based combined cycle propulsion system, the aircraft would use a turbine engine at low speeds and a scramjet engine at high speeds. The turbine and scramjet engines share common inlet and nozzle but with separate flow paths. The airframe of the aircraft is also designed to be part of the propulsion system: the forebody is a part of the intake airflow, while the aft section functions as an exhaust nozzle. There six scramjets on the aircraft and each produced about 325 kN of thrust, two turbine engines were located above the scramjets.

The fuselage of the X-35 was designed to have as little frontal area as possible to maximize aerodynamic efficiency at high speeds, the delta wings are also designed to have as little surface area as possible, to compensate for the wings, the fuselage can also generate additional lift.

Due to the predicted top speed of Mach 17, the X-35 used high performance carbon and ceramic composites which were made to only withstand the heating of mach 19. Shortly after peaking Mach 22 the aircraft broke apart and small to medium sized pieces crashed near the shore at Louisiana.

The X-35 is specially designed to be bottom heavy, this allows the Center of Mass to be lined up with the Center of Thrust, allowing the aircraft to fly at higher altitudes without losing control.

During flight, the X-35 would occasionally dive into the ground to gain faster speed, after reaching Mach 1 the scramjets will be activated however the turbine engines continue running. After reaching Mach 3 the turbine engines are cut off.

Today, a model of the aircraft is on display in the National Air and Space Museum.