Company Radian AviationThe company, which plans to develop a reusable orbital spaceplane, has begun flight tests of a prototype vehicle. The Seattle-based company announced on September 25 that it conducted the first series of taxi tests of the prototype aircraft, called PFV01, at an undisclosed Abu Dhabi airport in the United Arab Emirates. The tests involved what it calls “short hops” while testing the vehicle’s handling during takeoff and landing.

PFV01 is designed to test the aerodynamics of the company’s proposed Radian One, a space plane that would take off horizontally using a rail gantry system more than three kilometers long and reach orbit using rocket engines before landing on a runway. As currently designed, the vehicle can carry up to five people and 2,270 kilograms of cargo to low Earth orbit and return with 4,540 kilograms of cargo.

Radian has already done extensive computer modeling and wind tunnel testing of the design, chief technical officer and co-founder Livingston Holder said in an interview. “But we wanted to run the system to see if the analytical work done to date matched our predictions.”

Tests on the runway confirmed these models, he said. “It’s an important step to verify that the analytical models we use match what we see in real life,” he said.

The company conducted the test in Abu Dhabi with support from an unnamed partner. Holder said the test airport was a “good, supportive environment” and provided the company with daily access.

By testing here, Radian largely avoided export control issues because the twin-jet PFV01 did not contain any space technology, such as rocket engines, that would be subject to the International Traffic in Arms Regulations (ITAR). “We’re keeping it just for the aircraft because the aircraft part makes it easier for ITAR,” he said of the test.

The next phase of testing will involve moving the vehicle to another airport in the area with a longer runway to test its handling, allowing for more stable flights. “We’ve learned enough that we can start to open up the performance envelope,” Holder said. He didn’t offer a timeline for those tests, but they could involve the same PFV01 machine or a modified version to test different configurations.

Radian conducted taxi tests of PFV01 while doing other work on the spaceplane’s design. This included new tests of the thermal protection system developed by the company for the vehicle, as well as fabrication of a test fuel tank using composites.

“We’re very pleased with how things are going,” Holder said of the overall work on the spaceplane, with no major surprises in the development of the underlying technologies. “We’re making predictable progress toward results.”

Radian, which raised a $27.5 million seed round in early 2022, is working on its next round of funding but said it was too early to discuss specifics. The company has had good conversations with unnamed potential customers interested in the vehicle’s ability to deliver cargo both to and from orbit, he said. That has involved both signing letters of intent and converting those letters into contracts.

“It’s one thing for a company to have an idea of ​​what your product will do, how it will work, who will benefit from it,” he said, “and then try to figure out what the market will do. Do you really believe in what you believe in? And the answer is: they do.”