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Qian Xuesen Laid Foundation For Space Rise in China

(2009-08-09 12:47:20) 下一個
Qian Xuesen Laid Foundation For Space Rise in China

Jan 6, 2008
By Bradley Perrett

Nothing in aviation or space in 2007 represented a greater change in the status quo than China’s ascendancy to the first rank of space powers. China had proven its mettle four years earlier by becoming only the third member of the elite club of nations capable of flying humans in space. But in 2007, it accomplished two more feats, proving to the world that it’s a space player to be reckoned with across the board.

In January, China destroyed one of its own spacecraft with a ground-launched missile, shattering the aging weather satellite. Then in October, China launched its first planetary mission, sending a scientific probe to the Moon (see p. 59).

The man who laid the foundation for these achievements is a brilliant scientist who worked for the U.S. military on advanced rocket projects in the 1940s and helped found the Jet Propulsion Laboratory at the California Institute of Technology. Then, in a remarkably short-sighted move, the U.S. sent this man back to China with all his skills and knowledge of American secrets. With McCarthyism in full bloom, the scientist was deported on dubious charges of being a Communist.

That man is Qian Xuesen. And he became the father of the Chinese space program. (The name, sometimes spelled Tsien Hsue-shen, is pronounced chien shu-eh sen.)

The antisatellite (Asat) test demonstrated an ability—based on advanced sensors, tracking and precise trajectory control technologies—which had previously belonged only to the U.S. and Russia.

The Asat’s warhead, launched by a ballistic missile, intercepted its satellite target nearly head-on, creating an extremely high closing velocity that multiplied the challenges in this test and served to underscore the leap in Chinese technology.

The test was condemned worldwide as the largest instance of space pollution in history. Thousands of new pieces of debris, more than 900 of them large enough (10 cm.) to be tracked by ground radars, were suddenly in orbit. They threaten low orbiting satellites of all nations, including the International Space Station. The amount of space junk hurtling around the planet, accumulated in the 50 years since Sputnik, had shot up by 10% in an instant.

Worse, because the target satellite, at 860 km. (535 mi.), was fairly high, some fragments will take at least a century to be slowed down and brought back to Earth by the few molecules of atmosphere at that level.

China has not explained why, even if it felt it had to conduct the test, it did not use a specially built low-mass target that might have been blasted away at a lower altitude, leaving a smaller debris cloud of shorter duration. Soviet and U.S. Asat tests ended in the 1980s, when far fewer satellites were in low orbit and the dangers of space junk correspondingly lower.

While China’s space program began 2007 with a spectacular bang, it ended the year with a more peaceful, but still remarkable, achievement—when the country became the first developing nation to launch a spacecraft into lunar orbit.

The Chang’e 1 spacecraft is not in itself the main achievement. The platform is based on a communications satellite that China has been building for years. Rather, China has shown its greatest progress in mastering the challenge of tracking, telemetry and control technology needed to send a probe into deep space.

As with the Asat test, the message was that China had joined the front rank of space powers.

Qian Xuesen is not our Person of the Year because he personally directed these efforts. Now 96 years old and in poor health, he has not been active in the Chinese space program for many years. Rather, it’s because he, more than anyone, is credited with the leading role in creating the scientific and industrial complex that’s now reaching these heights of achievement.

He began to create it, in 1956, from almost nothing.

At the time, his Chinese colleagues knew little about rocket propulsion. His personal book collection became a key resource. And his first research institute had only one telephone.

“First we recognized that the pressing problem was to teach, not immediately to do independent research,” he later wrote. Fortunately, the Soviets gave crucial help for a few years.

The U.S. author Iris Chang, whose 1995 biography Thread of the Silkworm remains a leading source for information about Qian, wrote: “It was he who initiated and oversaw programs to develop some of China’s earliest missiles, the first Chinese satellite, missile tracking and control telemetry systems, and the infamous Silkworm [anti-ship] missile.

“And it was he who helped turn systems engineering into a science in China, by working out a management structure that would facilitate communication between tiers of experts with a minimum of confusion and bureaucracy.”

Spurred on by Qian, the Chinese moved from copying a Soviet R-2 (SS8209;2) missile, itself a development of the German A-4 (V-2) of World War II, to building a succession of progressively larger domestic designs, including the Dongfeng 4 ballistic missile, whose three-stage space launch version, Long March 1, put the first Chinese satellite into orbit in 1970.

Chang’e 1 was launched by a Long March 3A rocket, a development of the Dongfeng 5, for which research began as early as 1965.

“He’s the father of our space industry,” the head of China’s lunar program, Luan Enjie, once told U.S. journalist Michael Cabbage. “It’s difficult to say where we would be without him.”

The story of how China got Qian back from the U.S. has been told many times, not least in the early 1950s, when it was current news. But it’s a fascinating story, and is well worth retelling as we watch China’s latest strides forward.

Qian was born in 1911, in the last weeks of Chinese imperial history, and at 23 traveled to the U.S. on a scholarship to study aeronautical engineering at the Massachusetts Institute of Technology. Preferring theory to the practice that MIT then emphasized, he soon moved to Caltech and began to follow a path that would lead to his becoming one of the most eminent rocket scientists in the U.S.

While his own country was racked by political division, invasion by Japan and, finally, civil war, Qian became a star pupil of the director of Caltech’s Guggenheim Aeronautical Laboratory, the Hungarian-American engineer and physicist Theodore von Karman. Still in his 20s, Qian became involved in experiments in rocketry, a field that at that time, the late 1930s, was barely taken seriously.

But the U.S. Army Air Corps did begin to take it seriously in 1939, tasking Caltech, including Qian, to develop rockets to help bombers take off. As so often with rocket propulsion, the concept of what soon came to be called jet-assisted takeoff, or JATO, looks simple. Getting it to work led the team deeper into the struggle with propellants and combustion stability that helped make “rocket science” a byword for extreme technical challenge.

The 1943 discovery of German rocket activity resulted in acceleration in U.S. work and, at Caltech, the creation of the Jet Propulsion Laboratory, with Qian as a section leader directing research for Private A, the first U.S. solid-propellant missile to perform successfully.

The force that propelled Qian to the heights of the U.S. military technology establishment was the sudden realization of the potential of jet propulsion, including rockets. Almost ignored in the late 1930s, the technology rose by 1944 to first-rank development importance amid the largest war in history.

By early 1945, Qian was in the Pentagon with a high-grade security clearance and writing reports on the latest classified technology nationwide and its implications for future military development.

As a member of the U.S. technical mission that scoured Germany for secrets at the end of the war, he interrogated Wernher von Braun. No one then knew that the father of the future U.S. space program was being quizzed by the father of the future Chinese space program.

Von Karman vouched for Qian to join the Scientific Advisory Board, set up to advise the head of the Air Force. “At the age of 36, he was an undisputed genius whose work was providing an enormous impetus to advances in high-speed aerodynamics and jet propulsion,” von Karman later wrote, explaining the move.

In 1949, Qian described his idea for a spaceplane, a winged rocket that’s credited as an inspiration for the late 1950s Dyna-Soar project, itself an ancestor of the space shuttle.

Then his U.S. career suddenly unraveled. In 1950, as Sen. Joseph McCarthy (R-Wis.) raged against supposed widespread Communist infiltration of the U.S. government and with China now Communist, the authorities revoked Qian’s security clearance.

Iris Chang wrote that the Immigration and Naturalization Service had not a scrap of concrete evidence for its charge that Qian was a Communist.

But the government did have some evidence, even if it was far from concrete. And the U.S. had clearly found itself in a sticky situation with Qian. When China was a U.S. ally, any feelings of patriotism he might have had could do little harm to the U.S. But now that China was hostile, was it reasonable to let him learn more U.S. secrets? Maybe. He was seeking U.S. citizenship at the time.

Apparently insulted, Qian first responded to the loss of his security clearance by trying to return to China, but he was stopped by the government, which wanted to keep his knowledge of U.S. secrets inside the U.S. Then both sides changed their minds. The immigration service sought to deport him, regardless of the fears of other agencies, and Qian tried to stay, apparently determined to clear his name.

Qian’s attempt to stay almost certainly proves he wasn’t, in fact, interested in working for China. By that time he could have best done so by going home with his expertise and U.S. secrets. Without a security clearance, it was unlikely he could achieve much for China by staying in the U.S.

“It was the stupidest thing this country ever did,” said Undersecretary of the Navy Dan Kimball, who tried to keep Qian in the U.S. “He was no more a Communist than I was, and we forced him to go.”

The immigration service won its case against Qian, but the government still hesitated to send him back. After years in limbo, the scientist himself decided again to go home and sought help to do so from the Chinese government, which secured U.S. agreement as part of negotiations over Korean War prisoners.

China, of course, was delighted to have him back. It welcomed him as a hero when he was finally deported in 1955.

His reluctant return was hardly a patriotic act, but that was, and still is, overlooked in the official Chinese view of history. As recently as 2003, the Xinhua news agency, recounting his story, reported blandly: “In 1955, six years after the founding of New China, Qian Xuesen returned to the motherland.”

Another fact that’s ignored in China is that he gave bad scientific advice on agricultural yields that may have encouraged Chairman Mao Zedong’s disastrous 1958-61 Great Leap Forward economic policy, which led to perhaps 20 million people dying of starvation.

It turned out that some of the U.S. fears of sending Qian back may have been exaggerated. First, the secrets that he knew were at least five years old by the time of his return, and that was an era of rapidly changing technology.

Second, no single scientist or engineer can have more than a fraction of the knowledge needed to design space launchers or missiles. So he could only be a leader, not a one-man rocket builder. Indeed, his role turned out to be that of administrator of the Chinese space program. Moreover, Chang wrote that in many cases he told his questioning comrades that the technical answers they needed had already been published; they needed only to look up the right book, often an American one.

Finally, while he achieved great things for China as an administrator, those results again probably ended up serving U.S. interests, because China became an adversary of the Soviet Union within about five years of his return. Missiles built by the scientific-industrial complex he created were sent to the west of the country to bring Moscow in range.

But if China is now a strategic rival to the U.S., then his achievements are now more important than ever—especially as the Chinese economy moves relentlessly toward front and center on the world stage. Hence the continuing relevance of this very old man.
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