04. Rockets of the 20th Century

Submitted by mof_primary on Fri, 06/10/2011 - 5:57pm

Robert Goddard (left) at work on a rocket | The Museum of FlightBy Gus Posey, The Museum of Flight

In the early part of the 13th century, gunpowder-powered rockets became part of the arsenal of the Mongols, who borrowed the technology from the Chinese after seeing the effect of the rockets at the battle of Kai Fung Fu. During subsequent centuries, rocket technology advanced only incrementally, resulting in larger solidpropellant rockets, but little substantive change in how they were designed or built. It was not until the 20th century that the science of rocketry would change forever.

On March 16, 1926, Robert Goddard launched the first liquid-propellant rocket, a humble collection of pipes and valves powered upward by a reaction of liquid oxygen and gasoline. Though the flight was short (less than three seconds), it signaled a new era in controllable rockets. The primary disadvantage of the solidpropellant rockets that Goddard sought to displace was their inability to be used in increments; once a solid-propellant rocket begins to burn, it will continue until its fuel is exhausted.

Only three years before Goddard’s pioneering launch, Hermann Oberth, a Hungarian-born scientist living in Germany, published “By Rocket into Planetary Space.” This seminal work, later expanded to the much longer “Ways to Spaceflight,” influenced rocket development across Germany, including the formation of the Society for Spaceflight, a rocketry club that would eventually transform itself into a cadre of Germany’s top rocket scientists. In 1930, Oberth was assisted in a launch of a liquid-propellant rocket by a young rocket enthusiast named Wernher von Braun.

Von Braun’s dedication was quickly evidenced by the development of increasingly complex liquid-fuel rockets designed to propel aircraft and provide extra thrust during jet-assisted takeoffs. Working at their research facility at Peenemünde, von Braun’s team quickly moved forward on a variety of rocket designs, including the supersonic Wasserfall (Waterfall) anti-aircraft missile and the Aggregat 4, better known as the V-2.

Combining supersonic speed, a massive one-ton payload, and an early analog computer guidance system, the V-2 was the world’s first ballistic missile and the first rocket to travel to the edge of space. The name change came as the result of German propaganda, with the A-4 designation replaced by Vergeltungswaffe 2 (Vengeance Weapon 2). Following its first successuful flight in 1942, approximately 6,000 V-2 rockets were built and launched against targets in Belgium, France, England and the Netherlands, killing thousands. Because the V-2 was supersonic, it arrived silently, streaking down from space in a deadly arc, traveling at four times the speed of sound.

Although technically a success, the V-2 program produced mixed results. Von Braun’s rocket team had hoped to see the A-4 used to further the exploration of space, and watched helplessly as their project was transformed into a weapon of war. After the first V-2 struck England, von Braun remarked, “The rocket worked perfectly. It just hit the wrong planet.” Additionally, the production of the V-2 was accomplished using slave labor, forced to produce the deadly rockets in the horrific confines of an underground factory known as the Mittelwerk (Central Works) located near the town of Nordhausen. Almost 20,000 people died in the caves of Mittelbau-Dora, nearly three times as many victims as those targeted by the missiles.

At the end of World War II, von Braun and his team surrendered to American soldiers and were transported to the United States, where they began work at Fort Bliss, Texas. Relying on their extraordinary knowledge and the experience gained during their time in Germany, von Braun’s team accelerated the pace of American rocketry, using confiscated V-2 components to refine rocket designs.

In 1953, von Braun and his team launched the Redstone rocket, a highly accurate surface-to-surface missile that was a direct descendant of the German V-2. Because of its high success rate across a range of missions, the Redstone became known as “Old Reliable.” The Chrysler-built rocket carried a variety of payloads, including Ham the chimpanzee, the first primate in space, and Alan Shepard, the first American in space.

The skill of von Braun and his team quickly led to the development of other significant boosters. The Atlas missile used its 367,000 pounds of thrust to carry John Glenn into orbit, a much more complex flight than Shepard’s suborbital mission. The Titan rocket was more than five times as powerful as the original Redstone and was the first rocket to carry two Americans into space.

In 1960, NASA opened the Marshall Space Flight Center, and made von Braun its first director. One of the center’s first projects would be the creation of a large booster known as the Saturn rocket, designed to carry large payloads into orbit. In response to President Kennedy’s challenge to land a man on the moon, the Saturn booster was soon made a part of the Apollo program. On July 20, 1969, astronauts carried into space aboard a Saturn V rocket landed on the moon, a monumental accomplishment made possible by the extraordinary technical skill of von Braun and his team.

Following the final mission to the moon in 1972, the Saturn booster was used to place other payloads in orbit, including the American space station Skylab. Soon after, however, NASA began to examine a system that combined both solid- and liquidpropellant rockets with a reusable orbiter. This revolutionary combination came to be known as the space shuttle.