WASHINGTON — Virgin Galactic is making progress in the development of its next SpaceShipTwo suborbital spaceplane, although the company is saying little about when its existing SpaceShipTwo will be ready to resume test flights.

In a Jan. 8 statement, Virgin Galactic announced that the next SpaceShipTwo vehicle achieved a milestone called “weight on wheels,” where the vehicle supported itself solely using its landing gear. All the major structural elements of the vehicle are also in place.

The company said that this vehicle reached the “weight on wheels” stage of completion “considerably faster” than for the previous vehicle, VSS Unity, although it did not quantify how much faster the production went. The company credited the faster production to “a more efficient, modular assembly process, as well as experience curve benefits.”

The new SpaceShipTwo still has considerable work ahead of it before it is ready for flight tests. Virgin said that upcoming work includes connecting the vehicle’s integrated systems and completing “final structural closeouts,” followed by ground tests. The company didn’t disclose a timetable for completing the vehicle or starting flight tests.

“We now have two spaceships which are structurally complete, with our third making good progress,” said George Whitesides, chief executive of Virgin Galactic, in the statement. That third vehicle, the company said, is currently in the part fabrication phase. “These spaceships are destined to provide thousands of private astronauts with a truly transformative experience by performing regular trips to space.’’

The company’s update about the new SpaceShipTwo vehicle said nothing about the status of VSS Unity. That vehicle made its last suborbital test flight in February 2019, after which the company said it would then outfit the spacecraft’s cabin for commercial flights and make other upgrades.

Virgin Galactic officials, in comments last summer and fall, were vague about when that work would be completed and VSS Unity transported from the company’s manufacturing facility in Mojave, California, to Spaceport America in New Mexico for a final series of test flights. Whitesides, in an interview in October when the company started trading on the New York Stock Exchange, said that move would take place in late 2019.

A company spokesperson said Jan. 8 that the company was working on plans to move VSS Unity to New Mexico, but didn’t disclose a date. Whitesides, in a Jan. 9 interview on CNBC, said the vehicle would move to New Mexico “pretty soon.”

Building a fleet of SpaceShipTwo vehicles is key the company’s long-term plans. In a September 2019 investor presentation, the company said it expects to have a fleet of five SpaceShipTwo spaceplanes by 2023, a production rate of one per year. That would allow the company to generate positive earnings by 2021, growing to $274 million by 2023, assuming commercial operations start in June 2020.

Whitesides didn’t explicitly confirm in the CNBC interview that commercial flights will begin in in the middle of the year. “Our plan is to take each step as it comes. We want to be very safe,” he said when asked about that schedule. “Obviously, our number one priority this year is to fly Richard Branson to space. That’s going to be a huge moment.”