Chinese Hypersonic Engine Wins Award, Reshapes Speed Race?

China starts flying at Mach 5

By Jeffrey Lin and P.W. Singer | Published Oct 8, 2015 7:01 PM

Technology

TRCC engines mean China could fly Mach 6 airplanes—like the one shown in this fan art—that could fly anywhere in the world in under three hours. It would mean speeds and altitudes not yet used by modern air defenses. Grassroots (artist)

“The Chinese nation is no longer satisfied with living like a farmer who eyes nothing but his own piece of land and a family to raise. We are looking up into space now.”

Scramjet Concept

This schematic from a Chinese academic journal shows a proposed Chinese scramjet. The scramjet developed and flown by Professor Wang’s group would likely resemble this drawing.

This is what China’s state owned Global Times newspaper declared Upon NASA’s discovery of liquid Martian water last week. And thanks to Professor Wang Zhengou of the National Defense Science and Technology University, China has a critical piece of technology not just to get into space, but also into the global hypersonic arms race.

Feng Ru

Professor Wang Zhenguo was one of the nine recipients of the 2nd Feng Ru awards at CSAA’s biennial conference in September 2015.

Scramjet engines mix together air and liquid fuel at supersonic speeds, to result in the rapid combustion that propels aircraft and missiles at hypersonic speeds over Mach 5. In September 2015, Professor Wang received an award from the Chinese Society for Aeronautics and Astronautics (CSAA) for the successful development of China’s first scramjet engine over the past decade. In fact, Professor Wang took the top billing at the 2nd China Aeronautical Science and Technology Conference (CASTC2015) Feng Ru Aviaion Science & Technology Elite Awards (Feng Ru was an early 20th century Chinese aviation pioneer). CSAA took pains to mention that the kerosene-powered scramjet engine has successfully conducted flight tests, which makes China the second nation in the world, after the American X-43 and X-51 test vehicles, to develop a working scramjet engine for sustained atmospheric hypersonic flight.

JF-12 Hypersonic Wind Tunnel

The JF-12 Hypersonic Wind Tunnel began operations in March 2014. It is the world’s largest hypersonic wind tunnel, capable of achieving speeds of Mach 5 to Mach 9.

While China’s seemingly sudden success in hypersonic flight may be surprising to outside observers, hypersonic technology is a key part of the national security 863 research initiative. In spite of longstanding Chinese difficulties in building turbofan engines, scramjet engines are a vastly different and emerging field that China has a opportunity to build a lead in. Along with the successful hypersonic glider vehicle WU-14 tests (which demonstrated Chinese capability in working high strength, thermal resistant aerospace materials), China has the world’s largest hypersonic wind tunnel, the JF-12. The JF-12 can produce speeds of up to Mach 9 (NASA”s hypersonic wind tunnel reaches to only Mach 7). The JF-12 would provide Chinese scientists with a convenient way to observe supersonic airflow of different scramjet configurations, in addition to directly testing material durability in laboratory conditions, rather than having to make difficult and expensive high-altitude engine test flights.

The Missing Drone

China was rumored to make the first flight of a Mach 4+ test drone in September 2015. Launched from a H-6 carrier aircraft, the drone fired up its combined cycle turbo-ramjet engine to accelerate from subsonic to high supersonic speeds. If the yanked CNA report is accurate, the UAV’s ability to land makes it the fastest recoverable air breathing aircraft in the world.

Professor Wang’s award comes after an interesting rumor making the rounds about Chinese supersonic flight. On September 18, 2015, China Aviation News, a respected source on Chinese aerospace developments, posted an article on the successful test flight of a Mach 4+ reusable UAV testbed that used a variable cycle turbo-ramjet engine (the engine uses a turbofan/turbojet at lower speeds, but redirects air to the ramjet at speeds above Mach 2.0). In comparison, the SR-71 only flew at speeds of about Mach 3.2. However, China Aviation News quickly yanked the article in a matter of hours, suggesting that they may have inadvertently (or deliberately as a signal) posted restricted information.

Combined Cycle Engine

The combined cycle engine shares the same inlet and exhaust nozzle for both the turbojet/turbofan and ramjet. In the upper diagram, the air intake ramps behind the ramjet spike direct airflow into the turbo core. In the bottom diagram, the air intake ramps gradually block off air flow to the turbo core, redirectly air into the ramjet combustion engine for high supersonic (Mach 3.0-Mach 4.0). Chinese combined cycle engines like this concept could be combined with the new scramjet to power hypersonic Chinese planes and missiles.

If it has flown, the Chinese variable cycle engine could be combined with Professor Wang’s scramjet to form the holy grail of hypersonic flight, a combined turbine/scramjet engine. Such a combined engine would use subsonic speeds to takeoff, power the ramjet to high supersonic speeds, before transforming into scramjet mode for speeds above Mach 5. Lockheed Martin has proposed using a similar concept of combined engines for the Mach 6 SR-72, a near-space UAV, to the US Air Force.

Shadow Dragon Hypersonic Bomber

The Shadow Dragon hypersonic bomber concept, from the PLAAF’s Engineering College, won a second prize in the 4th National Future Aircraft Design Competition at the 2010 Zhuhai Airshow. The Shadow Dragon and other aircraft like it would be powered by scramjet technology that China is now racing to take a lead in.

That China has made so much progress in the new field of air breathing hypersonic flight graphically illustrates the ability of military newcomers to gain rapid advances in emerging technologies.

Thanks to Sinowarrior, John Fryer, Jeff Head and Andreas Rupprecht

CSAA 2015 Awards Professor Wang is the third entry before the bottom of the page, his entry has been shortened (possibly to conceal scramjet technical details).