NASA and SpaceX have updated their plans for spacecraft-to-spacecraft propellant transfer development. Currently, the company and the agency are working on developing fuel transfer hardware, and the first ship-to-ship test is scheduled for next year.

This is a major milestone in developing a lunar lander for the Artemis program. SpaceX’s Starship will serve as the primary Human Landing System (HLS) in the American-led campaign to return to the moon since 1972. To function as an HLS, a starship will need to be able to refuel in orbit before going to the Moon and landing upon it.

First Things First: Starship Development Must Advance

SpaceX has flown Starship five times thus far, and has shown great progress with each successive flight of the world’s largest and most powerful rocket. While there have been some spectacular explosions and apparent failures during each test flight, SpaceX has claimed that each of the five flights successfully achieved its primary objectives.

There have also been some spectacular successes — on the first flight, Starship was able to lift off and fly with a controlled ascent, the second saw improvements to the first flight plus the Ship (the Starship second stage) nearly reached orbit, for example. The most recent test, IFT-5, was perhaps the most successful of them all: the first stage of Starship returned to its launch site where it maneuvered with precision while under thrust and was capture in the “chopsticks” — arms designed to support the stage rather than it landing on the ground.

SpaceX has announced a sixth flight test of the Starship stack and plans to conduct the launch no earlier than November 18th of this year. SpaceX plans to continue developing ascent, staging, and subsequent Ship flight to near-orbit, and also the booster once again returning to the launch site for a catch, reigniting a Ship Vacuum Raptor engine while in space, and testing a suite of heatshield experiments and maneuvering changes for ship reentry and controlled landing in the Indian Ocean.

While those are notable milestones for each successive flight of the world’s largest and most powerful rocket to have ever flown, SpaceX still has a lot of work to do before Starship will be ready to transfer propellant between spacecraft. First, they must perfect re-entry of the second stage, the Ship. Each test flight thus far has resulted in notable damage to the control surface (flaps) of the Ship, something that must be overcome long before the spacecraft can be considered reusable. SpaceX has also not completed an orbital flight of Ship. Finally, they have yet to demonstrate reusability by flying a first stage a second time. Later, a Ship. Then they must perfect operational processes to do those things over and over again.

Given their track record of fast improvements and iterations, it’s almost safe to say that SpaceX will overcome those issues quickly with each successive test flight. The flight cadence of Starship flights has been relatively low (by SpaceX standards) mainly due to bureaucratic delays in licensing, which SpaceX has complained about loudly and publicly.

With a new presidential administration set to take office in two months, SpaceX is hopeful that new leaders bring new rules that in turn allow them to increase their test flight cadence to tackle the aforementioned outstanding issues as well as testing and perfecting other ones — precision maneuvering while in orbit, for example.

There’s a long way to go.

SpaceX has thus far delivered on its projects, and given the progress shown thus far with Starship, it seems like only a matter of time before they have an initial operational version of Starship ready to fly from Texas and Florida to orbit, with propellant transfer testing following that at some point soon afterward. Late is better than never.

SpaceX and NASA seem increasingly confident that the ongoing Environmental Impact Study for Starship launches from Pad LC-39A will be positive, clearing the way for the company to build and finalize the infrastructure necessary to fly and land Starship at Kennedy Space Center. The Draft version of that EIS should be released in the next few months, stay tuned.

The Propellant Plan

NASA’s update contains some interesting items: the Flight System Review for the HLS propellant transfer system has been completed, and the development and testing of the hardware designed to accomplish the task is underway.

The goal, according to NASA, is a Ship-to-Ship propellant transfer demo sometime next year, in 2025.

On the surface, a propellant transfer test in 2025 may seem like an aspirational goal for 2025, one set in mud rather than carved into stone. Perhaps. There is a long way to go to complete the development of the world’s most powerful and largest rocket in human history to the point where propellant transfer testing will be possible. SpaceX may encounter bumps in the road or even roadblocks in that effort — in fact, it is more likely than not.

To overcome those inevitable issues, the company needs an increased flight cadence of Starship flights, and to get that, they need a sea-change in the regulatory landscape, with the FAA and other federal government agencies acting far faster than they have thus far. The new administration may well make that sea-change happen quickly, especially since Starship development is currently a long pole for NASA’s plans to return humans to the moon’s surface.

If SpaceX can conduct more test flights of Starship and if the federal government’s mechanisms aid rather than hinder the company, a 2025 test seems entirely possible. If the FAA requires a thorough investigation after each flight that takes months to complete, then 2025 is off the table.

Perhaps retired astronaut Clayton Anderson puts it best when he says, “Never bet against SpaceX.” Anderson is right, as SpaceX has consistently delivered on its promises. How long does it take for the Starship Human Landing System? Only time will tell.

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Here’s a great recap of Starship’s fifth test flight that SpaceX released on November 6th: