Virgin Orbit is moving ever closer to launching a rocket to space for the first time.

Why it matters: The company is one of a number of private spaceflight companies aiming to capitalize on what it sees as a boom in demand for small spacecraft launches.

The company's unique flight profile hinges on its LauncherOne rocket mounted beneath the wing of an ex-Virgin Atlantic Boeing 747 jet.

During a launch, the rocket is designed to drop from the wing and ignite its engine, lofting relatively small payloads to orbit from high altitude.

This saves on fuel, since the rocket doesn't have to travel through the thickest parts of the atmosphere.

Driving the news: On Sunday, Virgin Orbit — which was spun off from Richard Branson's human spaceflight-focused Virgin Galactic — conducted another test flight of its "Cosmic Girl" plane. The company also flew another test flight last Thursday, and it's gearing up for more.

The 2 tests over the last week were both "heavyweight" captive carry flights, meaning that LauncherOne was weighed down to simulate its expected heaviest weight at launch, but it never detached from the plane.

"All the design is done, all of the parts have been manufactured, every bit has been tested as a bit, so there's no need to wait around," Virgin Orbit vice president of special projects Will Pomerantz told Axios. "We're all fired up, and ready not just for our first flight but to get into commercial operations. It's intense, but fun."

What's next: For now, Virgin Orbit is staying mum on when it's planning to fly the first full test flight.

In the immediate future, the company will need to conduct a "drop test," where it drops the heavyweight rocket from the plane, letting it fall to test all its components without actually lighting up the rocket itself.

Virgin Orbit also has plans to launch from Japan and the U.K. when it starts flying.

The fact that its launcher is mobile allows it to operate in multiple countries.

Yes, but: While some experts have raised the concern that something of a "rocket bubble" is forming, Virgin Orbit is usually cited as a promising company in this space for its innovative launch mechanism.