Meanwhile Back in the United States

Even though a flood of embarrassing publicity had driven Robert Goddard to retreat into secrecy, some people learned of his work and took it seriously. One of the most important was Charles A. Lindbergh. Lindbergh was a national hero who, in 1927, had been the first to fly solo across the Atlantic Ocean. Lindbergh met

Robert Charles Permenter Roswell
Left to right: Daniel Guggenheim, Robert Goddard, and Charles Lindbergh in September 1935

with Goddard. He subsequently obtained a grant of fifty thousand dollars from the Daniel and Florence Guggenheim Foundation for the Promotion of Aeronautics to finance further work.

With this money, Goddard moved his research to Roswell, New Mexico. He remained there, with a few interruptions, from 1930 to 1941. At his Roswell laboratory, Goddard created large, sophisticated rockets. He tested new, lighter metals for construction; pumps for delivering fuel to the motors; controls for guidance; and other technology. In 1935 he launched a rocket 14.8 feet (4.5 m) long to an altitude of more than 4,790 feet (1,460 m).

Goddard could not interest the U.S. military in rockets. This left Goddard, as he said, "filled with disgust at the fact that no intensive fundamental work appears possible." In 1942, after the United States had entered World

(1,453 kg) of thrust for a full forty-five seconds. In addition, it was to be fitted with many technological improvements. For example, a gyroscopic control system could steer the rocket by adjusting vanes in the exhaust.

War II, he could only get work developing rockets to boost heavily laden aircraft at takeoff. Even though Goddard's work had little direct impact on the development of rockets in Germany, Wernher von Braun admired him. In 1970, twenty-five years after Goddard's death, von Braun said, "[Goddard] was the first. He was ahead of everyone in the design, construction, and launching of liquid fuel rockets which eventually paved the way into space. When Dr. Goddard did his greatest work, all of us who were to come later in the rocket and space business were still in [diapers]."

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Robert Goddard (second from right) and his team pose in front of one of the large Roswell rockets in the early 1930s.
Goddard (on the left) working in his Roswell workshop in 1940

Unfortunately, this sophisticated system was the rocket's undoing. While the A-3's engine and other systems performed perfectly, every test ended in a crash. The gyroscopic control had to be completely redesigned. The engineers redesigned much of the rest of the

Steering Rockets

Making rockets go in a certain direction had been a problem from the beginning. The early Chinese, Indian, and Congreve rockets used guide sticks, which were not very effective. Hale and others stabilized their rockets by making them spin like bullets. This made the rocket fly straight, but there was still no way to guide or correct its flight once it was launched.

In the 1930s, Goddard and Wernher von Braun used a gyroscope to detect changes in the course of their large rockets. Basically, a gyroscope is a rapidly spinning wheel or disk. This wheel resists any attempts to change the direction in which its axis is pointing. For example, the reason a standing bicycle will easily fall over, while one that is moving

gyrosoq

movable fins steer rocket

gimbal-

mounted movable motor steers rocket

A gyroscope can be used to guide a rocket in several ways. It can operate flaps on the fins of the rocket or vanes placed in the exhaust. It can also cause the engine itself to pivot in a special mounting called a gimbal.

movable fins steer rocket gimbal-

mounted movable motor steers rocket

A gyroscope can be used to guide a rocket in several ways. It can operate flaps on the fins of the rocket or vanes placed in the exhaust. It can also cause the engine itself to pivot in a special mounting called a gimbal.

rocket, as well. Because the designation A-4 had been reserved for the final, perfected rocket, the revamped A-3 became the A-5. It was a resounding success. During the next two years, nearly twenty-five were launched. Some of them made repeat flights after successful parachute recoveries.

The German air force, the Luftwaffe, was impressed by this progress and anxious to expand the work of the rocket team. It moved

The gyroscope in this 1930s Goddard rocket (left) helped keep it on a straight course by operating movable vanes (right) in the rocket's exhaust.

does not, is because of the gyroscopic action created by its spinning wheels. This resistance can be made to operate controls. If the gyroscope is in a rocket, these controls can operate a steering mechanism. In this way, if the rocket veers off its course, the gyroscope can make a correction.

This correction can be implemented in several different ways.

Fins can adjust the rocket's flight. Or vanes can be placed in the exhaust itself. When the vanes move, they redirect the exhaust in one direction or another. This causes the rocket's course to change. The motor can be placed in a special pivoted mount called a gimbal that allows the motor to pivot in any direction. This steers the rocket in much the same way an outboard motor steers a boat.

von Braun and his colleagues to a new facility being built near the Baltic fishing village of Peenemunde, Germany. Dornberger, promoted to full colonel, was in charge.

However, the Luftwaffe wanted a rocket that did more than just fly 10 miles (16 km). Large cannons could already fire a shell that far. The Luftwaffe informed Dornberger that if he wanted its continued support, his team would have to concentrate on creating a weapon that "could carry more payload than any shell presently in our artillery [and] ... farther than the maximum range of a gun."

Engineers calculated that the successful A-5 could be scaled up to the largest size that would still fit through a railroad tunnel (so it could be transported). The result would be a monster rocket 46 feet (14 m) long, 5.2 feet (1.6 m) in diameter, and 26,000 pounds (11,800 kg) when fully fueled. It could carry a payload of 1 ton (1 metric ton). It would be the biggest rocket ever built.

Fuel and oxidizer would need to be pumped into the mammoth 55,000-pound (25,000 kg) thrust engine. Previously, the fuel and oxidizer tanks of most rockets were pressurized. They used a gas such as nitrogen to force the liquid into the combustion chamber. But gas pressure would not be sufficient to feed fuel fast enough to the giant A-4 engine.

The A-4 would use turbine-driven pumps. Von Braun was delighted to discover that lightweight powerful pumps already existed for fire engines. The power for the turbine would come from the steam produced when hydrogen peroxide (H2O2) decomposes on contact with potassium permanganate (KMnOj.

Von Braun and his team were pushing known technology and engineering to the limits with their new rocket. No rocket this large or this complex had ever before been attempted. The first attempt to launch an A-4 occurred in spring 1942 and failed. The second test also failed. However, on the third try, on October 3, 1942, the giant rocket lifted flawlessly from its launchpad. It accelerated to a speed of 3,000 miles (4,830 km) per hour and rose to an altitude of 52 miles (84 km). This was really the fringe of outer space, which starts at about 50 miles (80 km). The rocket crashed to Earth 116 miles (187 km) from its launch point.

Peenemunde scientists insisted that the A-4 was not ready for field use. But the German army immediately began deploying the giant rocket. Renamed V-2 (Vengeance Weapon 2), thousands were launched

against British and Belgian targets during World War II.

The Descendants of the V-2

At the end of World War II, the United States acquired 118 of the best German rocket scientists and engi-

fueifor pumpsx rocket motor

„pay load instruments -and guidance

- alcohol liquid oxygen

. pumps steering vanes

The V-2 was the largest, most complex rocket built up to its time. It was a liquid-fuel rocket burning kerosene and liquid oxygen. Powerful pumps forced these liquids into the motor. It could carry 1 ton (1 metric ton) of high explosives as its payload.

neers, including von Braun. It also obtained one hundred fully functional V-2 rockets, rocket components, and literally tons of documents. The U.S. military had been anxious to get hold of the people and material because the Soviets also wanted to learn the secrets of German rocket development. Although the

Top rocket scientist Wernher von Braun (center, with broken arm) came to the United States from Germany at the end of World War II. He eventually led the U.S. missile program.

United States had gone into war reluctant to do any research into large rockets, the V-2 had shown the potential of rockets in future wars.

Robert Goddard—who died on August 10, 1945— examined one of these captured rockets. It was a terrible shock to the man whose pioneering work had been overlooked by the U.S. government. "I don't think he

Robert Goddard prepares to test a bazooka-type weapon he developed for the U.S. military in 1918. A small, solid-fuel rocket is inserted in one end of a hollow launching tube. The tube helps aim the rocket toward its target and helps protect the rocketeer launching it from the blast at takeoff.

ever got over the V-2," a friend observed. "He felt the Germans had copied his work and that he could have produced a bigger, better and less expensive rocket, if only the United States had accepted the longrange rocket."

Goddard was both right and wrong. The U.S. military had shown little interest in large-scale rockets during the war. Almost all the rockets used by U.S. forces were small, solid-fuel rockets, such as those used in the bazooka or some of the JATO jet-assisted takeoff) units. These were used only to boost heavy aircraft at takeoff. On the other hand, Goddard had his own desire for secrecy to blame. Too few people knew of his work, either in the United States or abroad.

The U.S. Army decided to catch up. Between 1946 and 1951, sixty-seven captured V-2s were launched—mostly at the army's White Sands

In one of the first U.S. experiments with JATO in 1941, a small Ercoupe plane, piloted by Lt. Homer A. Boushey, was boosted into the air by twelve solid-fuel rockets with 50 pounds (23 kg) of thrust each.

In one of the first U.S. experiments with JATO in 1941, a small Ercoupe plane, piloted by Lt. Homer A. Boushey, was boosted into the air by twelve solid-fuel rockets with 50 pounds (23 kg) of thrust each.

Proving Grounds in New Mexico. Ironically, this was only about 130 miles (209 km) from Roswell, where Goddard had performed his experiments.

Part of the army's experimental program was the Project Bumper. This involved the launch of two-stage rockets. These consisted of a V-2 with a smaller rocket, the WAC-Corporal, in its nose. On February 24, 1949, the WAC-Corporal became the first man-made object known to reach outer space.

The V-2, carrying the tiny WAC-Corporal, reached an altitude of 20 miles (32 km) and a velocity of almost 1 mile (1.6 km) per second. The motor of the smaller WAC-Corporal then ignited, adding its speed to that already gained by the V-2. By the time the WAC-Corporal ran out of fuel, it had accelerated to 1.4 miles (2.3 km) per second.

The V-2, meanwhile, continued to coast upward, reaching an altitude of 100 miles (161 km) before finally falling back to the desert.

The first launch of Project Bumper, in which a captured German V-2 rocket is carrying a smaller WAC-Corporal in its nose, took place in 1949.

Multistage Rockets

As a rocket travels, its fuel and oxidizer tanks will empty. Since the empty tanks are of no use, their extra weight only holds back the rocket. If it were possible to cut away the empty part of the fuel tanks as they drain, the rocket would be lighter and could go higher and faster. This is what happens in a staged rocket. But instead of literally cutting away the empty parts of a rocket, engineers stack one rocket on top of

1. The rocket takes off with the main stage lifting the two above it.

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