Lockheed announced that it is currently developing a mach 6 capable warplane under its Hypersonic test vehicle program. The program’s aim is to comply with the DARPA Falcon Project, an effort to develop hypersonic vehicles capable of performing airstrikes anywhere in the world within one hour, a military goal known as Prompt Global Strike (PGS).

According to Popular Mechanics, “The HTV-2 and HTV-3X are proposed unmanned transonic aircraft that could perform long-distance airstrikes. The HTV-2 has been part of two launch tests, but the HTV-3X program was put on hold due to budget shortages in 2008.

The HTV-2 is an experimental aircraft that is capable of achieving Mach 20 speeds, or about 13,000 miles per hour, after being launched on a rocket. Two HTV-2 launch tests were conducted, one in 2010 and one in 2011. After the second launch on a Minotaur IV rocket in 2011, the HTV-2 successfully hit speeds between Mach 17 and Mach 22 before crashing into the Pacific as a safety precaution.

The HTV-3X, referred to as Blackswift before the project stalled out in 2008, differs from the HTV-2 in that it would take off and land conventionally rather than be launched by rocket. The HTV-3X would be the size of a conventional fighter jet.”