The Stratolaunch Roc: World's largest airplane completes third test flight in Mojave
Jan. 23—As the home of some of the most dramatic flights in the history of commercial aerospace, Mojave Air and Space Port in eastern Kern County has nearly seen it all.
SpaceShipOne. SpaceShipTwo. Masten rockets landing vertically on a dime. And more.
But there's something about 250 tons of airplane — the largest jet aircraft on planet Earth — lifting up off the desert tarmac that must surely get one's heart pumping.
For only the third time, Stratolaunch LLC rolled out its massive Roc carrier aircraft on Sunday to perform a critical test flight, one of many incremental steps that will be needed for the flying giant to reach its full potential.
"We are advancing America's capability in hypersonic flight," Zachary Krevor, Stratolaunch president and chief operating officer, said in explaining the Mojave-based company's goals for the near future.
Hypersonic flight refers to flight the exceeds five times the speed of sound, or Mach 5. Currently, Russia and China are well ahead of the United States in this specialized technology, Krevor said. And that must change.
Nicknamed Roc, after the enormous mythical bird of prey, the plane, with its 385-foot wingspan, double fuselage and six turbofan engines, took off at 8:47 a.m. and flew for 4 hours, 23 minutes over the Mojave Desert — longer than it's ever flown before, Stratolaunch said in a news release.
Roc reached an altitude of 23,500 feet at an indicated air speed of 180 knots. According to Trevor, the flight further prepared the carrier aircraft to support future launches of its upcoming hypersonic testbed vehicle, Talon-A.
If all goes as planned, the Talon aircraft will exceed Mach 5 and beyond in testing that could potentially have both commercial and military use.
Launched from the Roc carrier aircraft, Talon-A vehicles are rocket-powered, autonomous, reusable testbeds carrying customizable payloads. This capability enables routine access to the hypersonic flight environment, which is critical for scientific research, technological development and component demonstration, Statolaunch said in the release.
Initial results from Sunday's test include:
—continued evaluation of the aircraft's performance and handling characteristics at increased speeds and altitude, and:
—validation of the left mid-main gear operations, including door operations and alternate gear extension of the left mid-main gear.
Sunday's "successful flight demonstrates and validates improvements to the carrier aircraft's systems and overall flight performance," Krevor stated in the news release. "We will take the data we gathered today and continue to advance the aircraft's operational performance to support hypersonic testing in 2022."
According to Krevor and Evan Thomas, who flew Roc in the co-pilot's seat on Sunday's flight, the partial gear retraction is a graduated approach, designed to build confidence in the landing gear and gear door hardware.
Thomas said there's a common misconception about flight testing. It's not about wrapping a heroic scarf around your neck and going after end-goals on the first few day out.
These tests are designed to reach their goals in increments, Thomas said.
Landing an aircraft of this size is nothing like landing a light jet, much less an airliner. A Boeing 747, for example, has 18 tires. Roc has 28, Thomas said.
Thomas lauded the work done by the entire flight team, including the pilot on Sunday's flight, Mark "Gidro" Giddings, and flight engineer Jake Riley.
In addition to testing the carrier aircraft, the team continues to make strides in building its first two Talon-A test vehicles, TA-0 and TA-1, the release said. TA-1 completed its initial power-on testing in late December, keeping the company on track to begin hypersonic flight testing later this year and ready to deliver services to government and commercial customers in 2023.
Steven Mayer can be reached at 661-395-7353. Follow him on Facebook and on Twitter: @semayerTBC.
