The country road leading to the entrance of Spaceport America will be closed for portions of six days this month, beginning Friday, April 10, to allow for testing of an experimental, unmanned, reusable drone billed as the world’s fastest aircraft.
Spaceport officials are tight lipped about what is being tested for which client and why the closure Is necessary, but this appears to be the latest test of the Quarterhorse Mk 2.1, manufactured by the Hermeus Corp. of Atlanta, Georgia, for the U.S. Department of Defense, recently renamed the Department of War.
The Quarterhorse is about the size of an F-16 jet fighter — 49 feet, 5 inches in length with a wingspan of 32 feet, 8 inches and a height of 16 feet. The drone is powered by a single Pratt & Whitney engine that combines a conventional jet turbine with a ramjet feature.
Ramjets, which require at least Mach 2 speed (1,535 miles per hour) to operate, begin to work efficiently at Mach 3 (2,300 mph per hour) and reportedly can operate up to Mach 6 (4,600 mph). Speeds like that previously required rocketry.
According to a Hermeus news release, the Quarterhorse’s first test flight was conducted in May 2025 at Edwards Air Force Base in California and the second was in March 2026 over White Sands Missile Range with takeoffs, landings and remote-controlled operations from Spaceport America.
The Sierra County Commission voted last month to close County Road A013 from Engle south to the county line (about 13 miles) between 8 a.m. and 3 p.m. April 10, 17, 23, 24, 27 and 28. Each test is to last no more than two hours. Sheriff’s deputies are to be stationed at either end of the closed road.
“Rancher will be notified by Spaceport and all staff and tenants as needed,” says the application.
Commissioner Sandy Jones voted with the other commissioners for the closure, but said he was concerned that in the past not everyone who might need to use the road has been notified of the closures or when the closures will be cancelled.
Sheriff Joshua Baker said he had no information about why the upcoming closure was needed, but they are usually due to safety concerns “if something is to go wrong.” If the tests are cancelled due to stormy weather, that will be posted on the county’s website, he said.
Maja Perez, the spaceport official who asked for the closures this month, said in her application that ithey are needed for “test flights unmanned aircraft and test article drop.” She said she could not say more about the test because “everything is private for our client.” Asked if she could name the client, she said “negative.” The application says the number of people attending the test is “N/A” for not applicable.
The public information officer for Spaceport America did not return a call asking for more information.
Spaceport America’s reticence may signal its increasing reliance on military activities. The U.S. Air Force used the spaceport for training in January and Lawrence Livermore National Laboratory in California plans to partner with Virgin Galactic, spaceport’s primary client, on future missions.
Spaceport’s latest list of clients does not mention Hermeus, but its website has a story about Hermeuis and the Quarterhorse test in March that includes a photograph of the large drone being pulled by a truck on a runway at Edwards Air Force Base. Hermeaus own website has numerous photos of the Quaarterhorse plus a story about the upcoming tests at Spaceport America, datelined Truth or Consequences.
Jones said he is aware of Hermeus tests because he has helped build facilities for the company on the spaceport. He said the semi-secrecy is because “if they disclosed a lot, they’re afraid people would go out there to take a look.”