Blackswift Hypersonic Aircraft Cruises at Mach 6
The new hypersonic project, dubbed Blackswift, shares the same take off and land normally approach. It aims for a more achievable speed of a Mach 6. Blackswift came from a DARPA project called Falcon that originally intended to build a family of hypersonic test vehicles.
Details of the project point to the famed Lockheed Skunk Works as the main contractor for the vehicle. Reports are saying information gleaned from several sources point to Blackswift being a fighter sized unmanned .
The propulsion system to take Blackswift to the Mach 6 speeds is a hybrid power plant consisting of a combination turbine engine and ramjet. The turbine engine would take the up to Mach 3 where the ramjet would kick in and carry the craft up to the Mach 6 cruise speed. Blackswift reportedly doesn’t have the backing of the at this time, which will obviously be crucial to the project reaching maturity.
Ten years after the retired the SR-71 spy plane, Lockheed Martin’s legendary Skunk Works appears to be back at work developing a new Mach-6 reconnaissance plane, sources said.
The has awarded Lockheed’s Advanced Development Projects arm a top-secret contract to develop a stealthy 4,000-mph plane capable of flying to altitudes of about 100,000 feet, with transcontinental range. The plan is to debut the craft around 2020.
The new jet — being referred to by some as the SR-72 — is likely to be unmanned and, while intended for reconnaissance, could eventually trade its sensors for weapons.
The new would offer a combination of speed, altitude and stealth that could make it virtually impervious to ground-based missiles, sources said. Even the SR-71 is said to have evaded hundreds of missiles fired at it during its long career, although some sustained minor damage.
But experts say enormous challenges remain. First, the SR-71’s top speed was about 2,200 mph. Pushing a plane at twice that speed in the thin air of the upper stratosphere would require exceptionally powerful engines. Second, friction at high speeds could reduce stealth.
Blackswift paves the way for US hypersonic aircraft development
The United States military will release a request for proposals (RfP) in the coming weeks for Blackswift: a programme that will lay the technological groundwork for a successor to the venerable SR-71 Blackbird supersonic reconnaissance aircraft.
US Air Force (USAF) Chief Scientist Mark Lewis said Blackswift, a project of the USAF and the Defense Advanced Research Projects Agency (DARPA), will pave the way for the development of a hypersonic aircraft, which he notionally dubbed the SR-72.
"Blackswift itself will not be the SR-72 but it will be the air force's first important step in seeing if we can get there," Lewis told Jane's following a 5 March briefing in Washington.
Lewis said he envisions an SR-72 conducting reconnaissance missions similar to an SR-71 but doing so at "hypersonic" speeds, which are considered to be M5 or higher.
Flying an aircraft at such high speeds will require a highly specialised hypersonic propulsion system; Blackswift aims to begin developing that technology.
Hypersonic ‘SR-72′ Up For Grabs
The Pentagon’s latest crack at a hypersonic aircraft is officially open for competition. The $750 million Blackswift effort is supposed to demonstrate an aircraft that can take off and land from a runway, and fly at over six times the speed of sound (A PDF of the Broad Agency Announcement is available here). If it works as planned (a big, big if), this could be the theoretical follow-on to the SR-71 Blackbird.

The official announcement, put out by the Defense Advanced Research Projects Agency (which is running the program together with the Air Force) describes Blackswift as a "reusable, air-breathing hypersonic testbed to demonstrate a runway take-off, Mach 6+ cruise for at least 60 seconds, lateral maneuver, aileron roll, and a runway landing. It is envisioned that flying this reusable hypersonic testbed in a relevant, flight environment will permit the future development of enhanced-capability reusable hypersonic cruise vehicles for intelligence, surveillance, reconnaissance, strike or other national need missions."
The competition announcement is something of a turnaround from previous hints about the nascent program, when Lockheed Martin seemed to have a lock on the contract. Since Blackswift grew out of the HTV-3X Falcon, a Lockheed design, it’s safe to say that the company still has a strong chance of nabbing this new contract. And if it does win, it would theoretically have the lock on a next-generation aircraft. So why is DARPA, which has a lot of acquisition flexibility, holding a competition?
Well, the BAA says that considering the "scope and importance of this program, the Government has elected to conduct an open competition in order to solicit the best technologies and approaches the aerospace community has to offer in the most effective and efficient program construct." Translated, that means: sole-sourcing a major aircraft program, in today’s contracting environment, is not likely to fly with the companies, Congress, or the Pentagon
.
So, who will build Blackswift? Well, I’m still not sure this project is going to get beyond the testbed, but Lockheed clearly has a home-team advantage. That said, Boeing, which lost its big tanker competition last week, has a strong record in hypersonics, so I’m sure they’ll take a crack at Blackswift. Northrop Grumman, which has in the past proposed at least VuGraph engineering for a hypersonic bomber, could also be a theoretical contender.
Blackswift: Cost vs. capability
If Osama bin Laden turns up to order a cup of tea at an outdoor café, Mark Lewis, the Air Force’s chief scientist, wants to take him out before he can pay his check. The question is how.
Reaper unmanned aerial vehicles armed with Hellfire missiles won’t work unless a terrorist leader decides to sip tea where the U.S. has uncontested control of the airspace, which is where the relatively low-flying Reapers must travel. Cruise missiles, at least for now, are either too easy to shoot down or not fast enough.
The answer, Lewis said, might lie in winning political commitment to explore an unmanned, faster-flying successor to the retired SR-71 Blackbird to be called the SR-72.
Defense officials are still analyzing whether there would be a mission for an SR-72, but Lewis said he’s “pretty optimistic on its utility.” Either way, Lewis said he wants research to go forward. That would mean construction of a demonstration plane called Blackswift as a takeoff on the Blackbird.
At the moment, Blackswift consists of an artist’s rendering and some conceptual work completed by Lockheed Martin Skunk Works in California, builder of the SR-71. In 2004, the Pentagon hired Skunk Works to build a series of hypersonic test aircraft, and, as part of that effort, engineers drew up plans for the Hypersonic Technology Vehicle-3X, a proposed Blackswift demonstration plane.
The Skunk Works series
Defense officials discussed the possibility of forgoing a competition and awarding a contract directly to Skunk Works, but in March, they invited firms to submit competing ideas for a Blackswift demonstrator, with work beginning in 2009. Boeing announced in July that it was in discussions with Lockheed Martin about participating in the program. Northrop Grumman would not say whether it submitted a proposal.
The demonstrator would take off from a runway and, after an initial acceleration period, run its experimental high-speed, or hypersonic, engine in the stratosphere for about 60 seconds, attaining a top speed of Mach 6, about twice as fast as the SR-71. The demonstrator would be slightly smaller than a fighter plane, or about the size of the D-21 reconnaissance drones released from the backs of SR-71 planes decades ago. As for an operational Blackswift, or SR-72, the payload capacity, size and speed have yet to be determined, but Lewis and other advocates have one specification clearly in mind. Whereas the SR-71 flew unarmed, defense officials plan to learn a lesson from the Reapers by arming the new plane. Its job would be to conduct intelligence, surveillance and reconnaissance or strike missions, undetected, within about four hours of a request from the highest levels of government.
That won’t be easy. An operational plane would take off from a runway under its own power, and fly reliably at low altitudes and also at 80,000 feet, where there is little oxygen for fuel combustion. Engineers also will need to prove that intelligence sensors and communications systems can survive the ride and work through the heat of hypersonic flight. The Pentagon projects the cost of building the Blackswift demonstrator at $800 million over five or six years, “with timelines slipping,” Lewis said. Within the Pentagon, what seemed like a firm plan is now “in flux,” he added.
The Air Force’s spending partner in the Blackswift program, the Defense Advanced Research Projects Agency, has told the Air Force it plans to stretch its financial contribution over more years, notwithstanding a memorandum of understanding signed with the Air Force in September 2007. DARPA would not confirm that it is backing off its investment.
“Funding and the [memorandum of understanding] is not something that we can discuss,” DARPA spokeswoman Jan Walker said by e-mail.
The news in Congress was equally bad for advocates. In May, the Senate Armed Services Committee voted to cut DARPA’s proposed $70 million Blackswift contribution for 2009 to $30 million. The Pentagon drafted an appeal to Congress to reverse the proposed cut, but for unknown reasons, did not officially send it. However, congressional staff members have seen the document. A draft obtained by C4ISR Journal, a sister publication of Air Force Times, cites strong support from then-Air Force Chief of Staff Gen. T. Michael Moseley and then-Secretary Michael W. Wynne. Moseley and Wynne were subsequently ousted by Defense Secretary Robert Gates for unrelated reasons, leaving Blackswift — at least temporarily — without a high-level patron.
The remaining DARPA Blackswift money in 2009 would be combined with $40 million from the Air Force, which had asked for $50 million. Blackswift advocates had hoped for $150 million in 2009, but now they might get half that.
The Senate committee questioned whether engineers could overcome the Blackswift technical hurdles “in the near term” and suggested that Blackswift might not deliver a “unique capability and operational utility” compared to possible development of hypersonic cruise missiles. The committee also questioned whether the Defense Department had invested in enough hypersonic research to make 2009 the right time to start Blackswift.
In their unofficial appeal, defense officials warned that without Blackswift, future U.S. intelligence could be “severely impaired” in peacetime or wartime. “The recent demonstration by the People’s Republic of China to shoot down one of its own satellites from low-Earth orbit highlights the vulnerability of U.S. ISR assets orbiting at similar altitudes. Moreover, this country’s low-speed, and relatively low-altitude, ISR platforms such as Global Hawk and [the RC-135] Rivet Joint are incapable of surviving in sophisticated anti-access environments,” defense officials wrote.
Blackswift’s advocates say they suspect the proposed cuts and delays stem from a fierce competition for defense dollars more than from a genuine disagreement over strategy. Lewis said he wants critics to think hard about that.
“If it’s Osama bin Laden, I don’t think we’d want to spare the expense,” he said.
Lewis suggested that a large fleet of Blackswift aircraft would not be required because the aircraft would be reserved for “high-value targets that are priceless in terms of the strategic and tactical impacts their removal would imply.”
Advocates argue the world has changed since the Air Force retired the SR-71 fleet in 1990 with great fanfare, and briefly reactivated the planes from 1995 to 1998.
Emerging anti-aircraft threats, high maintenance costs and improvements to spy satellites made a winning case for retiring the SR-71. In the intervening years, the U.S. developed new hypersonic technologies, China proved it has an anti-satellite weapon, and Reapers have been unable to find and target bin Laden. Neither has piloted bombers and fighters in the region.
“One thing forward-based fighters and bombers cannot offer is high-speed critical reconnaissance, like we had with the SR-71. We don’t have that capability right now. Or if we do, I don’t know about it,” said Leon McKinney, a St. Louis-based aerospace analyst who tracks hypersonic research.
With the Pentagon’s weapons budget expected to tighten, Blackswift’s survival under a new administration is, at best, unclear. Questions loom over how Blackswift would be used, and whether there might be more effective alternatives, said Theresa Hitchens, an analyst at the Center for Defense Information in Washington.
“You have to be really sure your [intelligence] is correct,” she said. “You’re essentially talking about pre-emptive strikes, or very near. No baby food factories; no Chinese embassies. Would you have time to evaluate [potential targets] in an hour? You’ve got to figure out exactly how you’re going to use this.”
Hitchens questioned the rationale of spending hundreds of millions of dollars to build an aircraft meant for hitting one particular type of target: a terrorist leader.
“Is it going to be worthwhile to spend this money for a target set of three people or four?” she asked.
At the very least, the Air Force needs to answer those questions before money is appropriated, she said.
Blackswift’s roots can be traced to the months after the Sept. 11 terrorist attacks, when the Bush administration decided to elevate fast-strike options into a national policy. U.S. commanders believed terrorists and other potential enemies were learning to recede into the mountains or deserts just out of reach of U.S. weapons. If an enemy was spotted rolling a missile to a launch pad, or terrorists gathered for a meeting, there might not be a weapon in range. The Pentagon’s Joint Requirements Council, consisting of senior commanders, called for development of “prompt global strike” capabilities. The goal was to be ready to strike targets anywhere in the world within an hour.
In 2003, DARPA marshaled U.S. contractors and government researchers around a new effort called the Force Application from the Continental United States, or Falcon, program. Falcon managers proposed developing unmanned hypersonic gliders, dubbed Common Aero Vehicles, which would be blasted into space atop a new class of cheap, small rockets also in development by DARPA. The gliders would re-enter the atmosphere within an orbit and glide for up to 3,500 miles. On a separate track, contractors were asked to submit ideas for a powered Hypersonic Cruise Vehicle that would take off from a runway in the U.S., fly at Mach 10 along the fringes of space, and strike targets anywhere in the world.
Politics and technical issues forced defense officials to think smaller. Government engineers began questioning the feasibility of building a Mach 10 aircraft with today’s technologies, especially one that would weigh up to 1 million pounds and strike targets globally. In 2005, Congress barred the Defense Department from researching installation of weapons on the Common Aero Vehicles, because the gliders could be viewed as space weapons. DARPA and the Air Force narrowed their focus to a powered hypersonic aircraft that, if made operational, could be stationed at U.S. bases abroad. It would not fly as high or as fast as the Hypersonic Cruise Vehicle, and would not have to ride on ballistic missiles like the hypersonic gliders. Critics feared countries might mistake a conventionally armed rocket for a nuclear missile. As Dennis Rizzardi, manager for unmanned systems at Lockheed Martin Skunk Works, recalls the discussion: “We didn’t want to start World War III: ‘Hey guys, [that rocket] was only conventional.’”
Blackswift was born. It would be a scaled-back version of the Hypersonic Cruise Vehicle concept. Gone from the vision of most advocates is the notion of applying force from the continental U.S. with a hypersonic plane.
“The reality is a hypersonic aircraft operating in Earth’s atmosphere won’t have that global range and would have to be launched either near or in theater. Or possibly [be] refueled, but that’s also quite a challenge,” Lewis said.
Propulsion solution needed
An operational Blackswift would take off from a land base toward an intended combat or ISR target, reach its top speed and altitude, and then maneuver onto a descent trajectory to survey or possibly drop bombs. Afterward, it would land on a conventional runway to be prepared for its next mission.
Before Blackswift can fly, a key issue must be resolved. The engines that would take Blackswift to the stratosphere do not yet exist. The brain trust of the DARPA-Air Force Falcon program is working to determine whether gas-turbine or rocket engines would be best suitable to bring the aircraft to Mach 4 or Mach 4.5 — the minimum speed at which so-called “supersonic combustion ramjet” engines can take over. The inlets of these engines are shaped to compress thin air at high altitudes for combustion, but they have trouble at lower altitudes.
“The rocket and turbine people each think they have the better solution,” Lewis said. “I’m the agnostic. Engineering expectation tells me the best way to get to hypersonic speeds is by rocket. The problem is they’re not reusable. And if you want to take off and land from a runway, you at least need to look carefully at the turbine.”
The Defense Department’s funding appeal makes it sound as if the decision has been made: “Air-breathing, hypersonic, turbine-based combined cycle propulsion is the key technology in realizing a reusable hypersonic airplane that can take off and land under its own power and is the top priority in the Blackswift program.”
McKinney said Blackswift’s development could be enhanced by the nearly parallel work on an Air Force test aircraft called the X-51, which would be dropped from a B-52 and boosted to hypersonic speeds by a rocket before its experimental scramjet engine kicked in. The Air Force originally billed the X-51 as an engine test bed for development of a new satellite launcher, but contractors have lobbied for its potential use as a hypersonic cruise missile. It has a fuel-cooled engine, which enables the craft’s engines to function at hypersonic speeds without overheating. It likely will fly by 2009, Lewis said.
Aside from propulsion, technical questions also remain about Blackswift’s intelligence operations. Like today’s aircraft, those operations would rely largely on Global Positioning System satellite readings to find targets or report positions into the military intelligence network the U.S. is developing.
“Can you get a GPS signal through the layer of plasma that forms on the exterior of a vehicle as it’s coming through space? Can I send telemetry information? Snap a great picture and send the data back, if flying at high speeds?” Lewis asked. “In every case, the answer will be yes, but it won’t be easy.”
Even advocates admit that high construction and maintenance costs likely would prohibit the widespread use of Blackswift on the battlefield.
If the desire to get bin Laden or, more likely, the next bad guy, does not persuade Congress and the next administration to support Blackswift, advocates have one more case to make. They note that Russia and China also have hypersonic research efforts. McKinney said it’s as though those countries understand what the Blackswift
backers are trying to get Congress to see in their stalled appeal: “The existence of a reusable hypersonic ISR platform able to penetrate and survive in highly defended territory with a sustained presence is a powerful and potentially situation-altering deterrent capability.”