Stratolaunch has announced the successful completion of its fifth flight test of Roc, the world’s largest flying aircraft. During the test flight, the aircraft flew for 4 hours and 58 minutes over the Mojave Desert and reached an altitude of 22,500 feet (6858 meters). This is the longest of all flights, which allowed to expand of the boundaries of this platform for launching aircraft from the air.
The Roc features a twin-fuselage design and the longest wingspan ever flown, at 385 feet (117 m). The Stratolaunch is powered by six Pratt & Whitney PW4056 engines positioned on pylons outboard of each fuselage, providing 56,750 lbf (252.4 kN) of thrust per engine.
The fifth flight test debuted a new pylon on the aircraft’s center wing that will be used to carry and release Talon-A hypersonic vehicles. Talon-A is a flexible, high-speed testbed built for hypersonic research, experiments, and enabling operational missions. The reusable testbed can carry customizable payloads at speeds above Mach 5. This testbed capability enables routine access to the hypersonic flight environment, which is critical for scientific research, technological development, and component demonstration.
The new pylon technology added to the Roc for this launch is comprised of a mini-wing and adapter that is constructed with aluminum and carbon fiber skins. It weighs approximately 8,000 pounds (about 3,629 kg) and occupies 14 feet of Roc’s 95-foot center wingspan, allowing for adequate space between the aircraft‘s dual fuselages for safe vehicle release and launch. The state-of-art structure also features a winch system that will load Talon onto the platform from the ground, expediting launch preparation and reducing the need for ground support.
“Today’s successful flight validates important hardware improvements to the carrier aircraft,” said Dr. Zachary Krevor, Stratolaunch Chief Executive Officer and President. “The pylon is a crucial component of our combined launch system, and I am proud of the team’s timely and quality integration work that occurred since our last test flight. It is through their dedication that we continue to make steady progress toward achieving our next milestones of Talon-A flight tests later this year.”
The team has also started the fabrication of a third vehicle, TA-2, the first fully reusable hypersonic test vehicle. The company anticipates beginning hypersonic flight testing and delivering services to government and commercial customers in 2023.