Radian Aerospace, a Seattle-based company developing a reusable orbital spaceplane, has initiated flight tests of its prototype vehicle, PFV01, at an undisclosed airport in Abu Dhabi, United Arab Emirates. The company confirmed on September 25 that it had conducted a series of initial taxi tests, including “short hops” to evaluate the vehicle's handling characteristics during takeoff and landing.
PFV01 is part of Radian's broader efforts to advance its proposed spaceplane, Radian One, which aims to carry up to five passengers and 2,270 kilograms of cargo to low Earth orbit before returning with up to 4,540 kilograms of payload. The spaceplane will use a horizontal takeoff system involving a rail sled more than three kilometers long, coupled with rocket engines for orbital ascent and a runway landing for re-entry.
Livingston Holder, co-founder and chief technology officer of Radian Aerospace, emphasized the significance of the tests. “We wanted to get a system in the air to see if the analytical work done to date matches our predictions,” he said. The taxi tests confirmed the company's previous computational models and wind tunnel experiments. “It's an important step, validating that the analytical models that we're using match what we're seeing in real life,” he added.
The prototype tests were conducted with the assistance of an unnamed partner in Abu Dhabi, where Radian found a conducive testing environment. Holder noted that the vehicle, powered by jet engines, contained no space-specific technology, allowing the company to avoid export control restrictions. “We're keeping this to the airplane side of things because the airplane part makes it easier from an ITAR standpoint,” he said, referring to the International Traffic in Arms Regulations that govern the export of space-related technologies.
Radian plans to move to a different airfield in the region for the next phase of testing, which will feature longer runway operations and extended flights. “We've learned enough that we can start opening the envelope of performance,” Holder said, though he did not specify a timeline for these future tests.
In parallel with flight testing, Radian is advancing other aspects of the spaceplane's development, including the thermal protection system and the production of a propellant test tank. Holder expressed satisfaction with the company's progress, stating, “We're making predictable progress toward our end results.”
Radian, which raised $27.5 million in seed funding in early 2022, is now preparing for its next funding round. The company is also engaged in discussions with potential customers interested in its cargo transport capabilities. Holder remarked, “It's one thing for a company to have an idea… and then to try and find out, does the marketplace really believe what you believe? And the answer is, they do.”
