A push for hypersonic weapons
more systematic, thoughtful process for asking precisely what missions we want to use these for, to compare their cost-effectiveness ... and analyze the benefits and risks,” James Acton, co-director of the nuclear policy program at foreign policy think tank Carnegie Endowment for International Peace, said of the accelerated hypersonic programs and their use in a potential arms race. “I don’t think that’s happening at the moment.”
There are plenty of cautionary tales — such as the Joint Tactical Radio System, a program that began in 1997 with the goal of developing new and powerful software to allow troops on the ground, at sea and in the air to communicate seamlessly. Technological challenges, however, hampered deployment and by 2006 the Pentagon had spent billions of dollars on alternate radio systems.
Concerns about North Korean missile development in the early 2000s led to the rapid development of missiles to shoot down incoming nuclear-tipped ballistic missiles. The Ground-based Midcourse Defense system was exempted from traditional Pentagon procurement and testing standards, and was deployed as it was being developed. Underground launch silos were built at Vandenberg Air Force Base near Lompoc, Calif., and Ft. Greely, Alaska, even as the missiles were undergoing intercept tests.
In those tests, the system has failed to destroy mock enemy warheads about half the time, which led many government and independent analysts to conclude that it is unreliable. As of 2016, the system has cost more than $40 billion.
“It’s so urgent, we have to build it,” Laura Grego, senior scientist in the global security program at the Union of Concerned Scientists, said of the thinking behind these snafus. “At least with strategic missile defense, that worked out really poorly.”
The U.S. has experimented with hypersonics since the 1940s, but despite incremental developments, researchers say there are still major technological hurdles.
One challenge is developing materials that can withstand blistering temperatures and still travel at high speeds.
“All the usual kind of materials that have been used to build missiles, whether ballistic or cruise, they just don’t work for hypersonics,” said Nikolai Sokov, senior fellow at the James Martin Center for Nonproliferation Studies in Monterey. “It’s incredibly challenging.”
Another daunting challenge is the supersonic combustion ramjet — or “scramjet” — engine that powers hypersonic cruise missiles such as those in the Air Force’s conventional strike weapon contract.
To get the missile to travel at speeds of Mach 5 or greater, the scramjet compresses air from the atmosphere and uses it as an oxidizer to burn fuel, rather than relying on a heavy oxygen tank. NASA’s X-43A program in the 2000s proved that a scramjet engine could work in flight, though it was tested on a small, experimental aircraft.
In 2013, a 25-foot-long X-51A Waverider demonstrator aircraft built by Boeing Co. was dropped from the wing of a B-52 and reached Mach 5.1 with the help of a scramjet. That successful test flight for the Air Force came after a previous attempt in which the vehicle was lost because of a faulty control fin.
Experts say those technology challenges make hypersonics a good candidate for rapid prototyping, a fairly new contract capability within the Pentagon that has fewer set requirements and allows for new ideas to be explored without an obligation for a full program investment. Under this capability, a prototype must be demonstrated within five years.
“You’re not going all in on something you’re not sure will pan out,” said Wong of Rand Corp.
Fast-tracking a prototype also allows contractors and the military to find technical shortfalls that might not have been noticed before, said John Hernandez, senior industry analyst for the aerospace and defense unit at research and consulting company Frost & Sullivan.
The Air Force said it felt ready to take smart risks and prototype hypersonics in three years, rather than the five to 10 it can take during a developmental program, because of work done by other military branches and the Defense Advanced Research Projects Agency.
The air-launched rapid response weapon — the contract awarded to Lockheed this month — is based on the tactical boost glide hypersonic program pioneered by DARPA and the Air Force. That program explored the feasibility of a hypersonic boost glide system, in which a rocket accelerates the vehicle before the payload separates and glides unpowered to its destination.
Work on that contract will be done by Lockheed Martin in Orlando, Fla., while the hypersonic conventional strike weapon is being worked on in Huntsville, Ala. The Air Force has targeted a 2021 early operational capability.
“We’ll learn from it, we’ll get to see what it will do,” said Col. Colin Tucker, military deputy to the deputy assistant secretary of the Air Force for science, technology and engineering. “The prototyping is to prove out the capability.”
There is now an added impetus with China and Russia’s hypersonics programs on the rise.
Earlier this month, China reportedly tested its experimental hypersonic glide vehicle and described the flight as a “huge success.” In March, Russian President Vladimir Putin, using animated videos and graphics, unveiled new nuclear weapons including a hypersonic missile that could evade missile defense systems.
The Russian Kinzhal, or “dagger,” is an air-launched ballistic missile that can reach speeds of Mach 10. Some analysts questioned Putin’s specific use of the word “hypersonic” to describe that weapon, noting that almost all ballistic missiles reach hypersonic speeds at some point during their flight.
About a month after Putin’s announcement, the Air Force awarded Lockheed Martin the hypersonic conventional strike weapon contract.
“I don’t think it’s a coincidence that the U.S. is reinvigorating efforts at a time when Russia and China are invigorating efforts,” Acton said. “Each of the three states is responding to each other.”