As long as the government shutdown continues, SpaceX won’t be able to test fire the company’s new Falcon Heavy rocket. The company needs support from the US Air Force to do the test, but too many personnel are furloughed and cannot help SpaceX conduct the firing. And that means the company can’t yet set a definitive launch date for the Falcon Heavy’s first flight, which was targeted for the end of January.

The Falcon Heavy is supposed to fly from a historic site at NASA’s Kennedy Space Center (KSC) in Cape Canaveral Florida, called LC-39A. It’s the same pad that was used to launch the Apollo missions to the Moon, as well as numerous Space Shuttle flights. And right now, SpaceX is gearing up to do an important test at the site called a static fire. It involves firing up all 27 engines on the Falcon Heavy while the vehicle is on the launchpad to go through the important first steps of flight, such as loading propellant and engine ignition. The static fire should tell SpaceX whether or not the rocket is ready to fly, and if the test is deemed a success, the company will likely set a target launch date.

it looks like that test will have to wait

However, it looks like that test will have to wait until the government shutdown is over. Because of the pad’s location, SpaceX relies on support from the Air Force’s 45th Space Wing, which oversees launches and operations at both KSC and the nearby Cape Canaveral Air Force Station. The 45th Space Wing is responsible for making sure people on the ground are safe during launches and tests, for instance.

But the 45th says it can’t do these crucial tasks during the shutdown. “Due to the shutdown removing key members of the civilian workforce, the 45th Space Wing will not be able to support commercial static fires taking place on KSC,” a spokesperson for the 45th Space Wing said in a statement to The Verge. “Without our civilian workforce, the 45th SW is unable to support launch operations as well.”

SpaceX originally thought the shutdown would not impact its schedule, but the company later confirmed to The Verge that the shutdown does indeed delay the test of the Falcon Heavy. “This shutdown impacts SpaceX’s Falcon Heavy demonstration, which is critical for future [national security space] missions,” John Taylor, a SpaceX spokesperson, said in a statement to The Verge. SpaceX has been trying to do a static fire in January, with the goal of flying at the end of the month. However, the test keeps getting pushed, making a February launch more likely — and now the furlough could push the flight even further.

And it’s not just the test that will be delayed, but future SpaceX flights that rely on Air Force personnel. “[The shutdown] also impacts critical missions for our customers, including important international allies, scheduled to launch shortly from Cape Canaveral and Vandenberg Air Force Base, as well as upcoming missions this spring to resupply the International Space Station.” SpaceX’s next launch is scheduled for the end of January out of Cape Canaveral Air Force Station, when the company will be sending up a communications satellite to be used by the government of Luxembourg.

Fortunately, the Senate is supposed to vote Monday at noon ET on a new spending bill that could temporarily fund the government, so it’s possible that SpaceX will be able to get back to normal operations soon. But in the meantime, the engines will stay silent at Cape Canaveral.