Radian Aerospace Begins Flight Tests of Orbital Spaceplane Prototype

Radian Aerospace, a Seattle-based company with ambitious plans to develop a reusable orbital spaceplane, has commenced flight testing of a prototype vehicle, marking a key step in its journey to revolutionize space access.

Radian Aerospace announced on Sept. 25 that it had conducted an initial series of taxi tests for its prototype flight vehicle, dubbed PFV01, at an undisclosed airport in Abu Dhabi, United Arab Emirates. These early tests included what the company referred to as “short hops,” allowing Radian to evaluate the handling characteristics of the vehicle during takeoff and landing.

The PFV01 tests are a crucial part of the company’s larger goal to validate the aerodynamic design of Radian One, a futuristic spaceplane intended to reach orbit via a horizontal takeoff system.

Testing the Future of Space Access

PFV01 serves as a testbed for Radian One, the company's proposed orbital spaceplane. This vehicle is envisioned to take off horizontally using a rail sled system more than three kilometers long. Once airborne, it would ignite rocket engines to propel itself into orbit, eventually returning for a runway landing.

Radian One could carry up to five crew members and 2,270 kilograms of cargo to low Earth orbit, while bringing back as much as 4,540 kilograms of cargo.

The company has already conducted extensive computer simulations and wind tunnel testing to validate the design of Radian One. However, the step to build and test a physical prototype was a necessary move to ensure the data gathered from simulations aligns with real-world performance.

“We wanted to get a system in the air to see if the analytical work done to date matches our predictions,” - Livingston Holder, Radian’s Chief Technology Officer and Co-Founder

The taxi tests in Abu Dhabi have thus far validated Radian’s modeling efforts.

“It’s an important step...Validating that the analytical models that we’re using match what we’re seeing in real life.” - Livingston Holder, Radian’s Chief Technology Officer

Conducting Tests in Abu Dhabi

Radian conducted the tests with the help of an undisclosed partner in Abu Dhabi. The chosen airfield provided a "good, permissive environment" that allowed daily access for testing, a crucial factor in maintaining the pace of their development program.

By performing the tests in Abu Dhabi, Radian also sidestepped potential export control complications related to space technology.

Since PFV01 is powered by jet engines rather than rocket engines, it doesn't involve space-specific technologies that would fall under the International Traffic in Arms Regulations (ITAR).

“We’re keeping this to the airplane side of things because the airplane part makes it easier from an ITAR standpoint,” - Livingston Holder, Radian’s Chief Technology Officer

Preparing for the Next Phase

Radian Aerospace is now preparing for more advanced flight tests, which will take place at a different airfield in the region with a longer runway. This will allow the company to expand the scope of its tests and conduct more sustained flights to evaluate the spaceplane’s handling characteristics at higher speeds.

“We’ve learned enough that we can start opening the envelope of performance,” - Livingston Holder, Radian’s Chief Technology Officer

No specific timeline for these tests has been announced. This next phase may involve either the current PFV01 vehicle or a modified version to test alternative configurations.

Future Development and Customer Interest

Alongside the PFV01 flight tests, Radian is continuing work on other crucial aspects of Radian One's design. This includes tests of the vehicle’s thermal protection system and the development of a composite propellant test tank, key technologies that will be necessary for the spaceplane to endure the extreme temperatures of space and reentry.

“We’re really pleased with how things have been going...We’re making predictable progress toward our end results.” - Livingston Holder, Radian’s Chief Technology Officer

Radian raised a $27.5 million seed funding round in early 2022 and is now working on securing additional capital. Radian has signed letters of intent with several parties, some of which have already been converted into contracts, signaling strong market interest in the spaceplane’s cargo capabilities.

“It’s one thing for a company to have an idea: this is what your product is going to do, how it’s going to work, who it’s going to be beneficial for...And then to try and find out, does the marketplace really believe what you believe? And the answer is, they do.” - Livingston Holder, Radian’s Chief Technology Officer

A New Era of Reusable Spaceplanes

Radian Aerospace’s progress represents an important milestone in the development of reusable spaceplanes, a technology that could dramatically lower the cost of access to space. By combining horizontal takeoff, reusable vehicles, and robust cargo capabilities, Radian One has the potential to reshape how we approach space missions, both for human crews and critical payloads.

With continued testing and development, the company is moving closer to making that vision a reality.