It seems the world just keeps adding entries to its flight history books recently. First we fly a helicopter drone on another planet; now we’re flying truly massive planes in the skies of our own.
With a wingspan of 117 meters (385 feet) and weighing in at around 250 tons, the Scaled Composites Model 351 Stratolaunch—nicknamed the Roc, after the gigantic bird of prey from Middle Eastern mythology—completed its second test flight over southeastern California’s Mojave desert, for a total of 3 hours and 14 minutes of flight time. The aircraft maxed out at an altitude of 4,267 meters (14,000 feet) and a speed of 320 kilometers per hour (199 miles per hour). Stratolaunch (the company) developed the eponymous aircraft in an effort to test its use in launching future hypersonic vehicles from the air and making orbital launches into space more accessible.
The aircraft itself is designed to fly with a maximum takeoff weight of 650 tons while only being operated by a team of three: two pilots and one flight engineer. Its wingspan makes it the largest to have ever been flown, beating out the short-lived Hughes H-4 Hercules, a World War II “flying boat” that only ever saw one test flight back in 1947. The giant aircraft stayed as an idea in the mind of Burt Rutan, Scaled Composites’ founder, for over 20 years before being pursued as a collaboration with Microsoft co-founder Paul Allen back in 2011. The two formed Stratolaunch with the Roc as its first realized development project. (The two previously collaborated on the SpaceShipOne project, an air-launched rocket-powered aircraft under their joint venture Mojave Aerospace Ventures, that retired back in 2004.) The Roc was then imagined as a way to launch satellites from midair.
The Roc lifted off the ground for its first test flight back in April 13, 2019; unfortunately, Paul Allen was not able to witness its maiden flight, as he passed away on October 15 of the previous year. Stratolaunch would be sold to its current owners by October 2019, with the Roc being repurposed as a mobile launch platform for hypersonic vehicles instead.
The company was pleased with the results of the second test flight, according to Stratolaunch chief operating officer Zachary Krevor during the post-flight news conference. “We’re very pleased with how the Stratolaunch aircraft performed today, and we are equally excited about how much closer the aircraft is to launching its first hypersonic vehicle.”
Stratolaunch will be developing their own hypersonic vehicles, with an 8.5-meter long (28-foot long) aircraft designated Talon-A being developed to be the first to be launched from the Roc. However, development will take some time; the first Roc test flight with an expendable, hypersonic Talon-A payload may push through as early as 2022, with a reusable Talon-A to launch from the Roc by 2023, according to Stratolaunch chief technology officer Daniel Millman. Results from the Talon-A test flights might be of use to the United States military, who have been developing their own hypersonic vehicles for quite some time.
Bibliography
- Gates, D. (2017, May 31). Paul Allen’s colossal Stratolaunch plane emerges from its lair. The Seattle Times. https://www.seattletimes.com/business/boeing-aerospace/allens-colossal-stratolaunch-plane-emerges-from-its-lair/
- Stratolaunch. (n.d.). Scaled Composites. Retrieved May 1, 2021, from https://www.scaled.com/portfolio/stratolaunch/
- Wall, M. (2021, May 1). Stratolaunch flies world’s largest airplane on 2nd test flight. LiveScience. Retrieved May 1, 2021, from https://www.livescience.com/stratolaunch-worlds-largest-airplane-roc-2nd-test-flight.html
