Hypersonic sled traveling at Mach 5.8 recovered for the first time in history, claims US Air Force

Earlier in March this year, the 846th Test Squadron at the Holloman Air Force Base in New Mexico successfully recovered a reusable sled traveling at the hypersonic speed of Mach 5.8, the U.S. Air Force said in a press release. This is the fastest ever sled recovery in the over three decades. 

The Holloman AFB is also home to the Holloman High-Speed Test Track (HHSTT) which was first built in 1949 to provide a realistic and cost-effective testing environment for weapons, systems, and components. The facility that serves all the units of the U.S. military also helps procurement agencies and defense contractors evaluate the technologies and components under development. 

The Holloman High-Speed Test Track 

The HHSTT was only 3,350 feet (1.021 m) long when built. Over the years, the track was lengthened and is currently 50,971 feet (15,536 m) long. That's a little short of the 10-mile mark. 

The tracks are used to launch rocket-powered test vehicles, also called sleds. More than 12,000 such sled tests have been conducted at the facility in more than five decades, and the facility has been operational. Apart from speed tests and aerodynamic tests, the facility has also been a test bed for other technologies such as rain and erosion tests and weapons dispensation tests. 

In addition to being the world's longest track, it also bagged the title of being the world's fastest in 2003, when a test sled clocked the hypersonic speed of Mach 8.6. This is traveling at a speed of 9,465 feet (2.8 km) per second.    

The track serves as a critical link between laboratory-type investigations and full-scale flight tests. Researchers can simulate selected portions of the flight environment under carefully controlled conditions at the HHSTT. 

Recovering hypersonic sleds

Hypersonic tests can reveal a lot about a weapon's flight performance, and survivability before more expensive flight tests begin. Also, once a weapon enters flight trials, the chances of recovering components to study flight impact reduce considerably. This is why the HHSTT has concentrated its efforts On Hypersonic Sled Recovery (HSR) as well. Recovered sleds can be used to collect critical post-test data, especially in new weapon systems such as hypersonic missiles. 

The 846 Test Squadron at HHSTT has been working to improve high-speed braking at the facility. In March, the testing team managed to successfully stop a reusable sled that was traveling at 6,400 feet (1,950 m) per second. 

"What you accomplished marked the fastest recovery of a monorail sled in over 30 years, and the first time we have recovered a planned reusable sled at those speeds ever," Lt. Col. Paul Dolce, Commander, 846th Test Squadron told the team members after the testing, the press release said. "These efforts will now set up our future HyTIP [Hypersonic Test and Evaluation Investment Portfolio] runs for success and add a new capability for our hypersonic customers."