Earlier in March this year, the U.S. Air Force successfully recovered a reusable sled traveling at hypersonic speed for the first time, making it a historic event for the team’s Hypersonic Sled Recovery (HSR) effort.
The latest tests by the 846th Test Squadron’s Holloman High-Speed Test Track (HHSTT) at Holloman Air Force Base in New Mexico successfully brought a sled traveling at 5.6 times the speed of sound to a stop. It involved using a rocket to accelerate a vehicle riding a monorail at ground level. This test marked the fastest recovery of a monorail sled in over 30 years.
As a ground-based test facility, the HHSTT provides a cost-effective, controlled test environment for high-speed weapons, systems, and components. The HHSTT was originally 3,350 ft (1,021 m) long when initial construction was completed in 1949. Over the years, the track was lengthened and is currently 50,971 feet (15,536 m) long. The tracks are used to launch rocket-powered test vehicles called sleds. More than 12,000 such sled tests have been conducted at the facility in more than five decades.
A wide variety of tests have been performed at the HHSTT, including aircraft crew-escape systems, rain, and particle erosion tests, impact testing, weapons dispense testing, electronic warfare, guidance system testing, and a wide array of aerodynamic tests.
The 846 Test Squadron at HHSTT has been responding to a significant increase in demand for hypersonic weapons testing, with a focus on improving its high-speed breaking capability in order to recover sleds for post-test analysis. According to the Air Force, the HHSTT is the only sled track capable of recovering sleds with test articles from velocities over Mach 5. In early March, the testing team managed to successfully stop a reusable sled traveling at 6,400 feet per second (1,951 m/s) on a monorail track.
“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,” Dolce said. “Truly historical in my books! This could not have been done without everyone here who works at the track. These efforts will now setup our future HyTIP (Hypersonic Test and Evaluation Investment Portfolio) runs for success and add a new capability for our hypersonic customers.”