The Shenlong Spaceplane: Hyperventilating Hypersonics or Real Threat?
"At a minimum, Washington should delay the planned 2010 retirement of the Space Shuttle until a new space plane can replace it, as a way to retain a deterring potential military capability. China’s unwillingness to comment on its military space plans, coupled with the Shenlong space plane, confirms its larger aversion to military transparency. The U.S. and its allies have little choice but to develop the capabilities to defend their interests and assets in space." – Richard Fisher in the 3 Jan 08 edition of the WSJ-Asia
"Paint, plywood and composite tile from local Home Depot – $125; Photoshop – $250; Tricking the US into keeping in service an obsolete and hideously expensive system – priceless" – Anonymous commentator
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A jet bomber makes an appearance at a May Day celebration, a satellite is orbited, a picture surfaces on the frontpage of a newspaper or in a blog and suddenly the status quo becomes the status quo ante…or does it? In each of those cases a fragment of reality challenges assumptions and forces a reassessment – but without a full(er) vetting, one runs the risk of over-reach.
Consider the first case. It is 1955. Tensions are high in the West as there are reports of a new Soviet bomber, the M-4 Bison (actually called the Malot or Hammer) in the February issue of Aviation Week that describe the bomber’s intercontinental range and ability to carry a hydrogen bomb payload. Serious news indeed for the US has only just begun tests of its own first true intercontinental jet bomber, the B-52. At the Soviet Aviation Day parade that July at the Tsushino Aerodrome, ten Bison bombers are flown past the stands which include the US Air attache and his assistants from the embassy. Out of sight, the ten bombers bank sharply, circle around and fly past the stands again. This is repeated a total of six times, leaving the impression that a total of sixty, not ten, operational bombers are in the inventory and flying. A shocked entourage reports this sobering statistic back to Washington and the Bomber Gap is born. One of the spin-offs of the bomber gap was the devlopment and imlpementation of the overflight program of Russia by U-2s which soon uncovered the fact that the US was well ahead of the Soviets in bombers before Powers’ shoot-down stopped further flights.
(1962 CORONA Imagery)
Of course the launch of Sputnik re-generated talk of a capabilities gap again – this time of a missile gap. And again, it wasn’t until apprproriate collection was in place – this time the CORONA program (the first IMINT, or imagery intelligence satellites). In each case, a little bit of leg was shown and speculation subsequently ran rampant. So is the Shenlong just a tantilizing sleight of hand or turn of the ankle? Or is it a serious challenge? The answer lies in intent and capabilties. Intent – if a clear line can be drawn from a-to-b-to-c, then certainly a very strong case can be made that this is the manifestation of a long-standing plan to meet some goal or requirement of the Chinese space program – military and/or civilian. Capability, because whether it has the Stars and Stripes or Chinese star painted on the side, the laws of physics, aerodynamics and a myriad of others play the same – they are truly non-statist and neutral, and so developmental efforts and lessons learned may be mapped to some degree across boundaries to derive a systems possbile capabilities.
"Tsien Spaceplane" (ca. 1949)
In last week’s article on the issue of ASAT debris, mention was made of the head of China’s space program, Qian Xusesen. Chinese by birth, raised in America, educated at Cal Tech he was one of the founders of what is known today as the Jet Propulsion Laboratory. yes, that JPL. At the age of 36, he was recommended to join the Scientific Advisory Board set up to advise the Chief of Staff of the Air Force – his primary field being high speed aerodynamics and jet propulsion. In 1949 he is credited with the idea of spaceplan that later served as the impetus for the Dyna-Soar project. Not long afterwards though, he was accused of Communist sympathies under the MacCarthyist purges that were underway and by 1956 was back in China.
A winged spaceplane made its apearance in the Chinese spaceprogram in the 1970’s, bearing an uncanny resemblance to the cancelled Dyna-Soar project. However, following the cancellation of the manned portion of the Chinese space program in 1980, a manned spaceplane wouldn’t make a reappearance until the 1990’s and in slightly different form. When manned space flight was again on the table in the 1990’s, the focus of the program was a manned space station and a space transportation system supporting it. The later, identified as the 863-204 space shuttle, under went an extended study to determine configuration – that study yielded no less than 11 design proposals ranging from a the extremely challenging, from a technology/engineering standpoint (the H-2 Horizontal Take-Off/Horizontal Landing, two-stage hypersonic vehicle to orbit) to a conventional capsule atop a conventional booster. While the later, the Shenzou – similar to Russia’s Soyuz was chosen as the most prudent and speediest way to get into space, the Ministry of Air’s Institute 611 design, based on the French Hermes, was deemed the most promising of the winged vehicles and identified for further development to assure China an advanced manned spaceflight capability. Interestingly enough though, the first public display of a putative manned shuttle was of a double-delta winged, single-tailed spaceplane equipped with three engines that was exhibited at the 2000 Hanover Expo exhibit – the Shenglong.
French Hernes Spaceplane (source: astronautix.com)
16 Dec 07 photo of Shenlong model (far) and Chinese Hermes (near) (source: strategycenter.net)
Looking again at the first photo it appears this is a scaled research model, likely a proof of concept that tracks with China’s continued interest in developing spacecraft along these lines. Lacking a prior program of hypersonic research such as the US enjoyed with the likes of the X-15 program (see the three volume history of hypersonic research in the Virtual Library for details on the US hypersonic effort from the X-15 through the NASP) means that the development process will be somewhat longer than that for say, the US or Russia because of the experience of their respective programs. In the hypersonic regieme the equations of supersonic flow no longer apply, with many/diverese interactions between shock waves and the flow field. Of particular interest and a problematic area, for example, is the area in the wingroot between the wing and the fuselage. Some can be modled in special wind tunnels, some by computer modeling, but eventually real-world application and testing will be required. So, with a nod to the humor of the anonymous commentator, we would submit that the object under the Xian H-6 is very much real and not Photoshopped fake.
That said – what would one expect the Chinese to do with such a craft in the full-size variant? Assuming, for now, that they ignore the fiscal lessons the US and Russia took from operating the Shuttle and developing the Buran respectively, there are the expected space transportation system operations similar to that of the shuttle supporting the ISS. The Chinese space station is planned for sometime in the post 2012 period. As announced in 2007 though this station sounds much smaller than the ambitious 20-tonne variant initially planned and announced in the 1992 plan, raising questions about the need for such a large vehicle for servicing a small station that will not be permanently manned.
Of course, it is at this point that the alarmists step to the fore with dire warnings and predictions of a new space bomber raining destruction on the US and allies from the untouchable regime of hypersonic flight at the edge of space.
Well. To support their thesis they point to a 2002 interview with Chinese space expert Dr. Zhuang Fenggan who, in the course of the discussion, described the dual use of the prospective shuttle – military and civil use. Pointing out six essential technologies to be solved to make the Shenlong successful, he lists hypersonic flight, long/high-endurance on orbit and a thermal management system (tiles) that not only can manage extremely high temperatures but also are more impact tolerant than those found with the shuttle as important and necessary technologies to solve. Additional technologies though that carry a military only purpose include stealth and precision attack.
It should be pointed out that the Shuttle early in its operational life, had a military use – primarily for placing sensitive military payloads in orbit. Indeed, recall that at one point, the plan was to launch military shuttle missions from Vandenberg AFB in California. But the Moonraker-esque idea of the shuttle as a battle platform on orbit? Flights of fancy then, more so now as the fragility of the thermal protection system has shown. The fact that the Chinese have identified a military use for a spaceplane follows discussion and advocacy in some quarters in this country for the same. Former SecDef Rumsfeld in arguing for a prompt strike capability called for a spaceplane bomber. Before glazing over at the prospects of hypersonic spacebombers dropping bombs from the sanctuary of near space and hypersonic flight, we hasten to point out that the regime of hypersonic flight is such that not only is the carrier subject to the thermal and aerodynamic loads, so are the weapons and sensors adding multiple layers of complexity. The laws of physics are also not repealed, George Lucas and Luke Skywalker notwithstanding, the tyranny of orbital mechanics must still be addressed and so again, the idea of a spaceplane running around zapping satellites at abandon is a bit on the fantasy side.
Is the Shenlong a threat then? Maybe – but we would submit not in the sense that others identify it as such. Our view lies in the body of knowledge gained in the hypersonic realm from research in and operation of the Shenlong and other spaceplane bodies. Such knowledge can then find application in other areas where there are weaponization possibilities. For example, breakthroughs in hypersonic research could lead to new missile warheads that have better chances of penetrating defenses by high-speed maneuvers or even hypersonic flight at altitudes not commonly thought of for hypersonic flight.
Let’s make no mistake – the Chinese have clearly made their intent known with regards to active military uses of space including employing weapons with their 2007 ASAT test. That is a substantive threat and needs to be directly addressed via diplomatic and counter-capability measures. What doesn’t need to happen is the kind of hyperventilation that has characterized the debate in the nuclear realm in the past (hence the examples provided above). The first step for the US would be a sound national space policy that synchronizes the efforts of industry, NASA and the military – as heretical as that may sound to some. It is necessary from both fiscal as well as a threat basis. It should also be developed in partnership and cooperation with friends and allies – ESA and Japan who, it must be acknowledged, are also competitors in the commercial realm. Research must continue in such areas as the upcoming X-37b Orbital Test Vehicle launch slated for later this year. As stated earlier, we need to look to both harden future critical satellites as well as develop prompt regeneration capabiilities – either orbital or alternate methods to replace damaged or destroyed satellites. Finally there is engagement with China over peaceful and military uses of space with a view to discouraging weapons in space.
It is not, however, a reason or rationale for extending the shuttle fleet past its planned closeout.
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