The U.S military has announced the fastest at 20 times the speed of sound. The Defense Advanced Research Projects Agency(DARPA), laid out its plan to develop and test-fly the hyper-sonic vehicle.
Gregory Hulcher said: “We do not yet have a complete hyper-sonic system solution.” Programs like Integrated Hyper-sonics will leverage previous investments in this field and continue to reduce risk, inform development and advance capabilities.
The Integrated Hyper-sonics program will focus primarily on five areas: thermal protection; aerodynamics; guidance, navigation and control (GNC); range/instrumentation; and propulsion. Thermal protection systems are a key requirement for hyper-sonic flight, which is traditionally defined as anything above Mach 5. Vehicles zooming through the atmosphere at Mach 20 experience temperatures in excess of 3,500 degrees Fahrenheit (1,927 degrees Celsius), DARPA officials said — hot enough to melt stainless steel.
Desired advances in aerodynamics and GNC technology will allow the X-plane to make real-time, in-flight adjustments to account for changing conditions — such as wind gusts — and let it glide safely to its destination. As far as propulsion goes, IH won’t simply adapt an existing rocket designed for space missions. Rather, DARPA is working on a new launch vehicle that would insert the X-plane into its desired trajectory, officials said. The hyper-sonic vehicle would also have its own integrated rocket to give it a boost during flight, they added. DARPA has had an active hyper-sonics research program for years. For example, the agency has conducted two flight tests of a prototype rocket-launched glider, called the Hyper-sonic Technology Vehicle 2 (HTV-2), in the last two years.
Further, the vehicle would be “recoverable,” according to the release — meaning the government could get it back. To help make all this happen, DARPA has started up a new program called Integrated Hypersonics. IH will build off previous Defense Department research into ultra-fast flight but will need to make some major strides of it’s own.