The US Air Force Research Laboratory (AFRL) has given the green light to start building a new hypersonic rocket capable of flying at eight times the speed of sound. Being developed in partnership with Generation Orbit Launch Services, the X-60A vehicle has passed its Critical Design Review and now moves into the fabrication phase in anticipation of its maiden flight sometime in 2020.
Creating a new generation of hypersonic aircraft isn't easy and it isn't cheap. In fact, one of the stumbling blocks for creating aircraft and missiles that operate at speed of over Mach 5 (3,806 mph, 6,125 km/h) is that the bills often mount faster than the technological hurdles present themselves.
To keep the budget busting to a minimum, the US Federal Aviation Administration-licensed Cecil Spaceport in Jacksonville, Florida and the Air Force Small Business Innovative Research program are looking at ways to reduce development costs by moving flights outside of traditional US Department of Defense flight test ranges.
One example of this is the X-60A, which was initially called the GOLauncher 1. The first Small Business program craft to gain an "X" designation, it's an air-dropped liquid rocket designed especially for hypersonic research for the AFRL, Aerospace Systems Directorate, High Speed Systems Division. Its purpose is to make development cheaper by increasing the frequency of test flights under hypersonic conditions.
The unmanned, expendable missile uses a Hadley liquid rocket engine that burns liquid oxygen and kerosene and is small enough to be dropped from an aircraft the size of a business jet. According to General Orbit, the liquid fuel makes the X-60A more flexible and has better performance over solid rocket boosters, while the small delta wing improves maneuverability.
Once dropped, the X-60A can reach speeds of up to Mach 8 (6,089 mph, 9,800 km/h) while sending back flight telemetry and other data. It can fly several flight profiles, but it is strictly a research platform that carries no orbital payloads.
Source: USAF