Robert H. Goddard | |
---|---|
Robert Hutchings Goddard (1882-1945) |
|
Born | October 5, 1882 Worcester, Massachusetts |
Died | August 10, 1945 Baltimore, Maryland |
(aged 62)
Education | Worcester Polytechnic Institute, Clark University |
Occupation | Professor, rocket scientist, physicist, inventor |
Known for | First liquid-fueled rocket |
Spouse | Esther Christine Kisk (m. 1924–1945) |
Robert Hutchings Goddard (October 5, 1882 – August 10, 1945) was an American professor, physicist and inventor who is credited with creating and building the world's first liquid-fueled rocket,[1][2] which he successfully launched on March 16, 1926. Goddard and his team launched 34 rockets[3] between 1926 and 1941, achieving altitudes as high as 2.6 km (1.62 miles) and speeds as high as 885 km/h (550 mph).[3][4]
As both theorist and engineer, Goddard's work anticipated many of the developments that made spaceflight possible.[5] Two of Goddard's 214 patents — one for a multi-stage rocket design (1915), and another for a liquid-fuel rocket design (1915) — are regarded as important milestones[6] toward spaceflight. His 1919 monograph, A Method of Reaching Extreme Altitudes, is considered one of the classic texts[7][8] of 20th century rocket science. Goddard successfully applied three-axis control, gyroscopes and steerable thrust to rockets, all of which allow rockets to be controlled effectively in flight.
Goddard received little public support for his research during his lifetime. Though his work in the field was revolutionary, he was sometimes ridiculed in the press for his theories concerning spaceflight. As a result, he became protective of his privacy and his work. Years after his death, at the dawn of the Space Age, he came to be recognized as the father of modern rocketry.[9][10][11] He was the first not only to recognize the scientific potential of missiles and space travel but also to bring about the design and construction of the rockets needed to implement those ideas.[12]
Goddard was born in 1882 in Worcester, Massachusetts, to Nahum Danford Goddard (1859–1928) and Fannie Louise Hoyt (1864–1920). Robert was their only child to survive; a younger son, Richard Henry, was born with a spinal deformity, and died before his first birthday.[13]
With the introduction of electric power in American cities in the 1880s, the young Goddard became interested in science. When his father showed him how to generate static electricity on the family's carpet, the five-year-old's imagination was inspired. Robert experimented, believing he could jump higher if the zinc in batteries could somehow be charged with static electricity.[14][15] Goddard halted the experiments after a warning from his mother that if he succeeded, he could "go sailing away and might not be able to come back." [14][16]
Goddard's father further encouraged Robert's scientific interest by providing him with a telescope, a microscope, and a subscription to Scientific American.[17] Robert developed a fascination with flight, first with kites and then with balloons. He became a thorough diarist and documenter of his work, a skill that would greatly benefit his later career. These interests merged at age 16, when Goddard attempted to construct a balloon out of aluminum, shaping the raw metal in his home workshop. After nearly five weeks of methodical, documented efforts, he finally abandoned the project, remarking, "Failior [sic] crowns enterprise." However, the lesson of this failure did not restrain Goddard's growing determination and confidence in his work.
He became interested in space when he read H. G. Wells' science fiction classic The War of the Worlds when he was 16 years old.[18] His dedication to pursuing rocketry became fixed on October 19, 1899. The 17-year-old Goddard climbed a cherry tree to cut off dead limbs. He was transfixed by the sky, and his imagination grew. He later wrote:
For the rest of his life he observed October 19 as "Anniversary Day", a private commemoration of the day of his greatest inspiration.
It has often proved true that the dream of yesterday is the hope of today and the reality of tomorrow.
The young Goddard was a thin and frail boy, almost always in fragile health. He suffered from stomach problems, colds and bronchitis, and fell two years behind his classmates. He became a voracious reader, regularly visiting the local public library to borrow books on the physical sciences.
Goddard's interest in aerodynamics led him to study some of Samuel Langley's scientific papers in the periodical Smithsonian. In these papers, Langley wrote that birds flap their wings with different force on each side to turn in the air. Inspired by these articles, the teenage Goddard watched swallows and chimney swifts from the porch of his home, noting how subtly the birds moved their wings to control their flight. He noted how remarkably the birds controlled their flight with their tail feathers — Goddard called these the birds' equivalent of 'ailerons.' He took exception to some of Langley's conclusions, and in 1901 wrote a letter to St. Nicholas magazine[22] with his own ideas. The editor of St. Nicholas declined to publish Goddard's letter, remarking that birds fly with a certain amount of intelligence and that "machines will not act with such intelligence."[23] Goddard disagreed, believing that a man could control a flying machine with his own intelligence.
Around this time, Goddard read Newton's Principia Mathematica, and found that Newton's Third Law of Motion applied to motion in space. He wrote later about his own tests of the Law:
I began to realize that there might be something after all to Newton's Laws. The Third Law was accordingly tested, both with devices suspended by rubber bands and by devices on floats, in the little brook back of the barn, and the said law was verified conclusively. It made me realize that if a way to navigate space were to be discovered, or invented, it would be the result of a knowledge of physics and mathematics."[24]
As his health improved, Goddard continued his formal schooling as an 18-year-old sophomore at South High School in Worcester in 1901.[25] He excelled in his coursework, and his peers twice elected him class president. At his graduation ceremony in 1904, he gave his class oration as valedictorian. In his speech, titled On Taking Things for Granted, Goddard included a section that would become emblematic of his life:
[J]ust as in the sciences we have learned that we are too ignorant safely to pronounce anything impossible, so for the individual, since we cannot know just what are his limitations, we can hardly say with certainty that anything is necessarily within or beyond his grasp. Each must remember that no one can predict to what heights of wealth, fame, or usefulness he may rise until he has honestly endeavored, and he should derive courage from the fact that all sciences have been, at some time, in the same condition as he, and that it has often proved true that the dream of yesterday is the hope of today and the reality of tomorrow.[26]
Goddard enrolled at Worcester Polytechnic Institute in 1904.[27] He quickly impressed the head of the physics department, A. Wilmer Duff, with his thirst for knowledge, and Professor Duff took him on as a laboratory assistant and tutor.[28] At Worcester, Goddard joined the Sigma Alpha Epsilon fraternity, and began a long courtship with high school classmate Miriam Olmstead, an honor student who had graduated with Goddard as salutatorian. Eventually, she and Goddard were engaged, but they drifted apart and ended the engagement around 1909.[29]
Goddard received his B.S. degree in physics from Worcester Polytechnic in 1908,[30] and after serving there for a year as an instructor in physics, he began his graduate studies at Clark University in Worcester in the fall of 1909.[31] Goddard received his M.A. degree in physics from Clark University in 1910,[32] and then stayed at Clark to complete his Ph.D. degree in physics in 1911.[33] He spent another year at Clark as an honorary fellow in physics, and in 1912, he accepted a research fellowship at Princeton University's Palmer Physical Laboratory.[34]
While still an undergraduate, Goddard wrote a paper proposing a method for "balancing aeroplanes." He submitted the idea to Scientific American, which published the paper in 1907.[30] Goddard later wrote in his diaries that he believed his paper was the first proposal of a way to automatically stabilize aircraft in flight.[30] His proposal came around the same time as other scientists were making breakthroughs in developing functional gyroscopes.
His first writing on the possibility of a liquid-fueled rocket came on February 2, 1909.[35] Goddard had begun to study ways of increasing a rocket’s efficiency using methods differing from conventional, powder rockets. He wrote in his journal about using liquid hydrogen as a fuel with liquid oxygen as the oxidizer. He believed a 50 percent efficiency could be achieved with liquid fuel.[35]
In the decades around 1910, radio was a new technology, a fertile field for innovation. In 1911, while working at Clark University, Goddard investigated the effects of radio waves on insulators.[36] In order to generate radio-frequency power, he invented a vacuum tube that operated like a cathode-ray tube. U.S. Patent 1,159,209 was issued on November 2, 1915. This was the first use of a vacuum tube to amplify a signal, preceding even Lee de Forest's claim.[37][38][39]
By 1913 he had in his spare time, using calculus, developed the mathematics which allowed him to calculate the position and velocity of a rocket in vertical flight, given the weight of the rocket and weight of the propellant and the velocity of the exhaust gases. His first goal was to build a sounding rocket with which to study the atmosphere. He was afraid to admit that his ultimate goal was space flight, since scientists, in America especially, did not consider such a pursuit to be real science, and the public was not ready to seriously accept it.[40]
Unfortunately, in early 1913, Goddard became seriously ill with tuberculosis and was forced to leave his position at Princeton. He returned to Worcester, where he began a prolonged recovery.[41]
It was during this period of recuperation that Goddard began to produce his most important work. As his symptoms subsided, he allowed himself to work an hour per day with his notes. He saw the importance of his ideas as intellectual property, and began working to secure those ideas. In May 1913, he wrote his first rocket applications. His father brought them to a patent firm in Worcester, who helped Robert refine his ideas for patent consideration. His first patent application was submitted in October 1913.
In 1914, his first two landmark patents were accepted and registered. The first, U.S. Patent 1,102,653, described a multi-stage rocket. The second, U.S. Patent 1,103,503, described a rocket fueled with gasoline and liquid nitrous oxide. The two patents would become important milestones in the history of rocketry.[42][43]
In the fall of 1914, Goddard's health had improved, and he accepted a part-time position as an instructor and research fellow at Clark University.[44]
His position at Clark allowed him to increase his research activities. He made orders of many different rocket supplies, and spent much of 1915 preparing for his first rocket tests.
Goddard's first test launch of a powder rocket came on an early evening in 1915 following his classes at Clark.[45] The launch was bright and loud enough to arouse the alarm of the campus janitor, and Goddard had to reassure the man that his experiments were serious and harmless. After this incident, Goddard took his experiments inside the physics lab to limit any disturbance.
At the Clark physics lab, Goddard conducted static tests of powder rockets to measure their thrust efficiency. He found his estimates were verified; powder rockets were only converting about 2 percent of their fuel into thrust. At this point he applied de Laval nozzles, which were typically used with steam turbine engines. The de Laval nozzles greatly improved thrust efficiency. By mid summer of 1915, Goddard had obtained an average thrust efficiency of 40 percent with nozzle velocities up to 6,730 feet per second.[46]
Later that year, Goddard designed an elaborate experiment at the Clark physics lab to prove that a rocket would perform in a vacuum such as space. He believed it would, but he had to show other scientists who did not.[47] He demonstrated that a rocket's performance actually decreases under atmospheric pressure.
From 1916-1917, Goddard built and experimented with ion thrusters, which he imagined could be used for propulsion at near-vacuum conditions at very high altitudes. The small glass engines he built were tested at atmospheric pressure, where they generated a stream of ionized air.[48]
By 1916, the cost of Goddard's rocket research had become too much for his modest teaching salary to bear.[49] He began to solicit potential sponsors for financial assistance, beginning with the Smithsonian Institution, the National Geographic Society, and the Aero Club of America.
In his letter to the Smithsonian in September 1916, Goddard claimed he had achieved a 63 percent thrust efficiency and a nozzle velocity of almost 8,000 feet per second. With these performance standards, he believed a rocket could lift a weight of one pound (0.45 kg) to a height of 232 miles (373.37 km) with an initial launch weight of only 89.6 pounds (40.64 kg).[50]
The Smithsonian was interested, and asked Goddard to elaborate on his inquiry. Goddard responded with a detailed manuscript he had already prepared, titled A Method of Reaching Extreme Altitudes.[51]
In January 1917, the Smithsonian agreed to provide Goddard with a five-year grant totaling $5,000.[52] Afterward, Clark was able to contribute $3,500 and the use of their physics lab to the project. Worcester Polytechnic Institute allowed him to use its abandoned Magnetics Laboratory on the edge of campus during this time as a safe place for testing.[53]
It wasn't until two years later, at the insistence of Arthur G. Webster, head of Clark's physics department, that Goddard arranged for the Smithsonian to publish his work.[54]
Not all of Goddard's early work was geared towards space travel. As the United States entered World War I in 1917, the country's universities began to lend their services to the war effort. Goddard believed his rocket research could be applied to many different military applications, including mobile artillery, field weapons and naval torpedoes. He made proposals to the Navy and Army. No record exists of any interest by the Navy to Goddard's inquiry. However, Army Ordnance was quite interested, and Goddard met several times with Army personnel.
During this time, Goddard was also contacted by a civilian industrialist in Worcester about the possibility of manufacturing rockets for the military. However, as the businessman's enthusiasm grew, so did Goddard's suspicion. Talks eventually broke down as Goddard began to fear his work might be appropriated by the business.
Goddard proposed to the Army an idea for a tube rocket launcher as a light infantry weapon. The Army agreed to a contract with Goddard for this research. The launcher concept became the precursor to the bazooka.[55] Using a music rack for a launch platform, Goddard demonstrated the weapon at Aberdeen Proving Ground two days before the Armistice that ended World War I.[56] Later, a former Clark University researcher, Dr. C. N. Hickman, continued Goddard's work on the bazooka, leading to the weapon used in World War II.
In 1919, the Smithsonian Institution published Goddard's groundbreaking work, A Method of Reaching Extreme Altitudes. The report describes Goddard's mathematical theories of rocket flight, his experiments with solid-fuel rockets, and the possibilities he saw of exploring the earth's atmosphere and beyond. Along with Konstantin Tsiolkovsky's earlier work, The Exploration of Cosmic Space by Means of Reaction Devices. 1903.,[57] Goddard's little book is regarded as one of the pioneering works of the science of rocketry. It was distributed worldwide and is believed to have influenced the work of subsequent pioneers such as Hermann Oberth and Wernher von Braun in Germany and Sergey Korolev in the USSR.
Goddard described extensive experiments with solid-fuel rocket engines burning high grade nitrocellulose "smokeless" powder. A critical breakthrough was the use of the steam turbine nozzle invented by the Swedish inventor Gustaf de Laval. The de Laval nozzle allows the most efficient ("isentropic") conversion of the energy of hot gases into forward motion.[58] By means of this nozzle, Goddard increased the efficiency of his rocket engines from 2 percent to 64 percent and obtained supersonic exhaust speeds of over Mach 7.[59][60]
Though most of this work dealt with the theoretical and experimental relations between propellant, rocket mass, thrust and velocity, a final section titled Calculation of minimum mass required to raise one pound to an "infinite" altitude discussed the possible uses of rockets, not only to reach the upper atmosphere, but to escape from Earth's gravitation altogether.[61] Included as a thought experiment was the idea of launching a rocket to the moon and igniting a mass of flash powder on its surface, so as to be visible through a telescope. He discussed the matter seriously, down to an estimate of the amount of powder required; Goddard's conclusion was that a rocket with starting mass of 3.21 tons could produce a flash "just visible" from Earth. Forty years later, Goddard's concept was vindicated when the Soviet space probe Luna 2 crash-landed on the Moon on September 14, 1959, though radio tracking did away with the need for flash powder.
Goddard eschewed publicity, because he did not have time to reply to criticism of his work, and his imaginative ideas about space travel were shared only with private groups he trusted. He did, though, publish and talk about the rocket principle and sounding rockets, since these subjects were not too "far out." In a letter to the Smithsonian dated March 1920, he discussed: photographing the Moon and planets from rocket powered flyby probes, sending messages to distant civilizations on inscribed metal plates, the use of solar energy in space, and the idea of high-velocity ion propulsion. In that same letter, Goddard clearly describes the concept of the ablative heat shield, suggesting the landing apparatus be covered with "layers of a very infusible hard substance with layers of a poor heat conductor between" designed to erode in the same way as the surface of a meteor.[62]
Every vision is a joke until the first man accomplishes it; once realized, it becomes commonplace.
The publication of Goddard's document gained him national attention from U.S. newspapers, most of it negative. Although Goddard's discussion of targeting the moon was only a small part of the work as a whole and was intended as an illustration of the possibilities rather than a declaration of Goddard's intent, the papers sensationalized his ideas to the point of misrepresentation and ridicule. Even the Smithsonian had to abstain from publicity because of the amount of ridiculous correspondence they received from the general public.
On January 12, 1920 a front-page story in The New York Times, "Believes Rocket Can Reach Moon," reported a Smithsonian press release about a "multiple charge high efficiency rocket." The chief application seen was "the possibility of sending recording apparatus to moderate and extreme altitudes within the earth's atmosphere," the advantage over balloon-carried instruments being ease of recovery since "the new rocket apparatus would go straight up and come straight down." But it also mentioned a proposal "to [send] to the dark part of the new moon a sufficiently large amount of the most brilliant flash powder which, in being ignited on impact, would be plainly visible in a powerful telescope. This would be the only way of proving that the rocket had really left the attraction of the earth as the apparatus would never come back."[65]
On January 13, the day after its front page story about Goddard's rocket, an unsigned New York Times editorial[66] scoffed at the proposal. The article initially expressed skepticism about the prospect of carrying meteorological instruments on a rocket:
It is not obvious, however, that the instruments would return to the point of departure. . . .for parachutes drift just as balloons do. And the rocket, or what was left of it after the last explosion, would need to be aimed with amazing skill, and in a dead calm, to fall on the spot whence it started. But that is a slight inconvenience. . . .though it might be serious enough from the [standpoint] of the always innocent bystander. . . .a few thousand yards from the firing line.[67]
The article pressed further on Goddard's proposal to launch rockets beyond the atmosphere:
[A]fter the rocket quits our air and really starts on its longer journey it will neither be accelerated nor maintained by the explosion of the charges it then might have left. To claim that it would be is to deny a fundamental law of dynamics, and only Dr. Einstein and his chosen dozen, so few and fit, are licensed to do that.
Finally, the Times pounced. It assumed, wrongly, that Goddard's understanding of Newton's laws was flawed:[67]
That Professor Goddard with his "chair" in Clark College and the countenancing of the Smithsonian Institution, does not know the relation of action and reaction, and of the need to have something better than a vacuum against which to react—to say that would be absurd. Of course he only seems to lack the knowledge ladled out daily in high schools.[67]
Unbeknownst to the Times, Goddard had already successfully tested Newton's law. As early as 1901, Goddard had performed informal tests that verified propulsion was possible with a floating object, and in 1915 he conducted laboratory experiments in vacuo at Clark University that confirmed that thrust was possible in a vacuum.
A week after the New York Times editorial, Goddard released a signed statement to the Associated Press, attempting to restore reason to what had become a sensational story:
Too much attention has been concentrated on the proposed flash pow[d]er experiment, and too little on the exploration of the atmosphere. . . . Whatever interesting possibilities there may be of the method that has been proposed, other than the purpose for which it was intended, no one of them could be undertaken without first exploring the atmosphere.[68]
In 1924, Goddard published an article "How my speed rocket can propel itself in vacuum" in Popular science that explained the physics and gave details of the vacuum experiments he had performed to prove the theory.[69] However, even so, after one of Goddard's experiments in 1929, a local Worcester newspaper carried the mocking headline "Moon rocket misses target by 238,799 1/2 miles."
As a result of harsh criticism from the media and from other scientists, and understanding better than most the military applications for which foreign powers could use this technology, Goddard became increasingly suspicious of others and often worked alone, which limited the impact of his work. Another limiting factor was the lack of support from the American government, military and academia as to the study of the atmosphere, near space and military applications. As Germany became ever more war-like, he refused to communicate with German rocket experimenters, though he received more and more correspondence from them.
Forty-nine years after its editorial mocking Goddard, on July 17, 1969 — the day after the launch of Apollo 11 — The New York Times published a short item under the headline "A Correction." The three-paragraph statement summarized its 1920 editorial, and concluded:
Further investigation and experimentation have confirmed the findings of Isaac Newton in the 17th Century and it is now definitely established that a rocket can function in a vacuum as well as in an atmosphere. The Times regrets the error.[70]
Goddard began experimenting with liquid oxygen and liquid-fueled rockets in September 1921, and tested the first liquid-fueled engine in November 1923. It had a cylindrical combustion chamber, using impinging jets to mix and atomize liquid oxygen and gasoline.
He launched the first liquid-fueled (gasoline and liquid oxygen) rocket on March 16, 1926, in Auburn, Massachusetts. His journal entry of the event was notable for its laconic understatement: "The first flight with a rocket using liquid propellants was made yesterday at Aunt Effie's farm." The rocket, which was dubbed "Nell", rose just 41 feet during a 2.5-second flight that ended 184 feet away in a cabbage field,[71] but it was an important demonstration that liquid propellants were possible. The launch site is now a National Historic Landmark, the Goddard Rocket Launching Site.
Viewers familiar with more modern rocket designs may find it difficult to distinguish the rocket from its launching apparatus in the well-known picture of "Nell". The complete rocket is significantly taller than Goddard, but does not include the pyramidal support structure which he is grasping. The rocket's combustion chamber is the small cylinder at the top; the nozzle is visible beneath it. The fuel tank, which is also part of the rocket, is the larger cylinder opposite Goddard's torso. The fuel tank is directly beneath the nozzle, and is protected from the motor's exhaust by an asbestos cone. Asbestos-wrapped aluminum tubes connect the motor to the tanks, providing both support and fuel transport.[72] This layout is no longer used, since the experiment showed that this was no more stable than placing the rocket engine at the base. By May, after a series of modifications to simplify the plumbing, the engine was placed in the now classic position, at the lower end of the rocket.
After a launch of one of Goddard's rockets in July 1929 again gained the attention of the newspapers, Charles Lindbergh learned of his work. At the time, Lindbergh had begun to wonder what would become of aviation in the distant future, and had settled on rocket flight as a probable next step. He contacted Goddard in November 1929. The professor met the aviator soon after in Goddard's office at Clark University.[73] Upon meeting Goddard, Lindbergh was immediately impressed by his research, and Goddard was similarly impressed by the flier's interest. He discussed his work openly with Lindbergh, forming an alliance that would last for the rest of his life. This is an example, when many wanted to take advantage of him or deemed him a "nut," of Goddard's complete openness with those who shared his dream and that he felt he could trust.[74]
By late 1929, Goddard had been attracting additional notoriety with each rocket launch. He was finding it increasingly difficult to conduct his research without unwanted distractions. Lindbergh discussed finding additional financing for Goddard's work, and put his famous name to work for Goddard. Into 1930, Lindbergh made several proposals to industry and private investors for funding, which proved all but impossible to find following the recent U.S. stock market crash in October 1929.[74]
In the spring of 1930, Lindbergh finally found an ally in the Guggenheim family. Financier Daniel Guggenheim agreed to fund Goddard's research over the next four years for a total of $100,000 (~$1.6 million today). The Guggenheim family, especially Harry Guggenheim, would continue to support Goddard's work in the years to come. The Goddards soon moved to Roswell, NM.[75]
Because of the military potential of the rocket, Goddard, Lindbergh, Harry Guggenheim, the Smithsonian Institution and others tried before World War II to convince the Army and Navy of its value. Goddard's services were offered, but there was no interest, initially. Two young imaginative officers eventually got the services to attempt to contract with Goddard just prior to the war. The Navy beat the Army and secured his services to build liquid-fueled rockets for jet assisted take-off of aircraft. These rockets were the precursors to some of the large rocket engines that launched the space age.[40]
With new financial backing, Goddard eventually relocated to Roswell, New Mexico in 1930, where he worked with his team of technicians in near isolation and secrecy for a dozen years. Here they would not endanger anyone, would not be bothered by the curious, and experienced a more moderate climate (which was also better for Goddard's health).
By September 1931, his rockets had the now familiar appearance of a smooth casing and tail fins. He began experimenting with gyroscopic guidance and made an unsuccessful flight test of such a system in April 1932. A gyroscope mounted on gimbals electrically controlled steering vanes in the exhaust, similar to the system used by the German V-2 over 10 years later.
A temporary loss of funding from the Guggenheims forced Goddard to return to Clark University until 1934, when funding resumed. Upon his return to Roswell, he began work on his A series of rockets 4 to 4.5 meters long, powered by gasoline and liquid oxygen pressurized with nitrogen. The gyroscopic control system was housed in the middle of the rocket, between the propellant tanks. In March 28, 1935, the A-5 successfully flew to an altitude of 1.46 kilometres (0.91 mi; 4,800 ft) using his guidance system. This rocket also achieved supersonic velocity.
In 1936-1939, Goddard began work on the K and L series rockets, which were much more massive and designed to reach very high altitude. This work was plagued by trouble with engine burn-through. Goddard had built a regeneratively cooled engine, which circulated liquid oxygen around the outside of the combustion chamber, in 1923 but deemed the idea too complicated. He was therefore using fuel curtain cooling, spraying excess gasoline on the inside wall of the combustion chamber, but this was not working well, and the larger rockets failed. Returning to a smaller design again, the L-13 reached an altitude of 2.7 kilometres (1.7 mi; 8,900 ft), the highest of any of Goddard's rockets. Weight was reduced by using thin-walled fuel tanks wound with high tensile strength wire.
From 1940–1941, work was done on the P series of rockets, which used propellant turbopumps (also powered by gasoline and liquid oxygen). Higher fuel pressure permitted a more powerful engine, but two launches both ended in crashes after reaching an altitude of only a few hundred feet. The turbopumps worked well, however.
Goddard was able to flight test many of his rockets; but many resulted in what the uninitiated would call failures because of engine malfunction or loss of control. Goddard did not consider them failures because he felt that he always learned something from a test. Most of his work involved static tests, which are a standard procedure today, before a flight test. Between 1930 and 1945, the following 31 rockets were launched:[76]
Date | Type | Altitude in feet | Altitude in metres | Flight duration | Notes |
---|---|---|---|---|---|
December 30, 1930 | Goddard 4 | 2000 | 610 | ? | record altitude |
September 29, 1931 | Goddard 4 | 180 | 55 | 9.6 s | |
October 13, 1931 | Goddard 4 | 1700 | 520 | ? | |
October 27, 1931 | Goddard 4 | 1330 | 410 | ? | |
April 19, 1932 | - | 135 | 41 | 5 s | |
February 16, 1935 | A series | 650 | 200 | ? | |
March 8, 1935 | A series | 1000 | 300 | 12 s | |
March 28, 1935 | A series | 4800 | 1460 | 20 s | record altitude |
May 31, 1935 | A series | 7500 | 2300 | ? | record altitude |
June 25, 1935 | A series | 120 | 37 | 10 s | |
July 12, 1935 | A series | 6600 | 2000 | 14 s | |
October 29, 1935 | A series | 4000 | 1220 | 12 s | |
July 31, 1936 | L series, Section A | 200 | 60 | 5 s | |
October 3, 1936 | L-A | 200 | 60 | 5 s | |
November 7, 1936 | L-A | 200 | 60 | ? | |
December 18, 1936 | L series, Section B | 3 | 1 | ? | Veered horizontally immediately after launch |
February 1, 1937 | L-B | 1870 | 570 | 20.5 s | |
February 27, 1937 | L-B | 1500 | 460 | 20 s | |
March 26, 1937 | L-B | 8000-9000 | 2500–2700 | 22.3 s | Highest altitude achieved |
April 22, 1937 | L-B | 6560 | 2000 | 21.5 s | |
May 19, 1937 | L-B | 3250 | 990 | 29.5 s | |
July 28, 1937 | L-series, Section C | 2055 | 630 | 28 s | |
August 26, 1937 | L-C | 2000 | 600 | ? | |
November 24, 1937 | L-C | 100 | 30 | ? | |
March 6, 1938 | L-C | 525 | 160 | ? | |
March 17, 1938 | L-C | 2170 | 660 | 15 s | |
April 20, 1938 | L-C | 4215 | 1260 | 25.3 s | |
May 26, 1938 | L-C | 140 | 40 | ? | |
August 9, 1938 | L-C | 4920 (visual) 3294 (barograph) |
1500 1000 |
? | |
August 9, 1940 | P-series, Section C | 300 | 90 | ? | |
May 8, 1941 | P-C | 250 | 80 | ? |
As an instrument for "reaching extreme altitudes", Goddard's rockets were not very successful; they did not achieve an altitude greater than 2.7 km (in 1937), at a time when airplanes could reach up to 15 km and balloons 22 km. By contrast, German rocket scientists had already achieved an altitude of 3.5 km with the A-2 rocket (in 1934), reached 12 km by 1939 with the A-5 and 84 km in 1942 with the A-4 (V-2), reaching the outer limits of the atmosphere.
Goddard's pace was slower than the Germans' because he did not have the resources they did. But he was trying to perfect his rocket and the subsystems such as guidance and control so that it could achieve high altitudes without tumbling in the rare atmosphere and provide a stable vehicle for the experiments it would eventually carry. He was on the verge of building larger rockets to reach "extreme altitudes" when World War II intervened and changed the path of American history.
Though Goddard brought his work in rocketry to the attention of the United States Army, he was rebuffed, since the Army largely failed to grasp the military application of large rockets.
German military intelligence had once paid attention to Goddard's work. An accredited military attache to the US, Friedrich von Boetticher, sent a four-page report in 1936, and the spy Gustav Guellich sent a mixture of facts and made-up information, claiming to have visited Roswell and witnessed a launch.[77][78] But thereafter the Germans received very little information about Goddard.
The Soviet NKVD had a spy in the U.S. Navy Bureau of Aeronautics. In 1935 she gave them a report Goddard had written for the Navy in 1933. It contained results of tests and flights and suggestions for military uses of his rockets. The NKVD considered this to be very valuable information. It provided few design details, but gave the Soviets the direction and progress of Goddard's work.[79]
Don't you know about your own rocket pioneer? Dr. Goddard was ahead of us all.
A frequently repeated story, launched by Goddard himself, declared that at the end of World War II Goddard saw the remnants of the German V-2 ballistic missile and was convinced that the Germans had stolen his work. Although Goddard did study a V-2, there is confusion as to how it was obtained and also just how influential Goddard had been on its design.
In the spring of 1945 Goddard saw a captured German V-2 ballistic missile which had been sent to the naval laboratory in Annapolis, Md. where Goddard had been working under contract. It is not out of the question that parts were despatched to Goddard in Annapolis, but there would not have been much time: Goddard died of throat cancer in August 1945.
One opinion, described in the May 1959 issue of Popular Science[81] would have it that the V-2 which he inspected was wreckage retrieved from a test flight that had crashed in Sweden (the so-called Bäckebo Bomb). This wreckage had been analyzed and reconstructed by British (not US) engineers at Farnborough from July 1944 as part of Project Big Ben.
Another view is that this was not the wreckage from Sweden, but an unlaunched rocket that had been captured by the US Army from the Mittelwerk factory in the Harz mountains. Samples captured here were first shipped back by Special Mission V-2 on 22 May 1945.[82]
After a thorough inspection Goddard was convinced that the Germans had "stolen" his work. Though the design details were not the same, the basic design of the V-2 was similar to one of Goddard's rockets. The V-2, however, was technically far more advanced than the most successful of the rockets designed and tested by Goddard. The Peenemünde rocket group led by Wernher von Braun may have benefited from the pre-1939 contacts to a limited extent, but had also started from the work of their own space pioneer, Hermann Oberth; they also had the benefit of intensive state funding as a war project, large-scale production facilities (using slave labor), and repeated flight testing that allowed them to refine their designs. Nonetheless, in 1963, von Braun, reflecting on the history of rocketry, said of Goddard: "His rockets...may have been rather crude by present-day standards, but they blazed the trail and incorporated many features used in our most modern rockets and space vehicles".[83]
Goddard avoided sharing details of his work with other scientists, and preferred to work alone with his technicians. Frank Malina, who was then studying rocketry at the California Institute of Technology, visited Goddard in August 1936. Goddard refused to discuss any of his research, other than that which had already been published in Liquid-Propellant Rocket Development. Theodore von Kármán, Malina's mentor at the time, was unhappy with Goddard's attitude and later wrote, "Naturally we at Caltech wanted as much information as we could get from Goddard for our mutual benefit. But Goddard believed in secrecy.... The trouble with secrecy is that one can easily go in the wrong direction and never know it." Goddard's concerns about secrecy led to criticism for failure to cooperate with other scientists and engineers.
By 1939, von Kármán's Guggenheim Aeronautical Laboratory at Caltech had received Army Air Corps funding to develop rockets to assist in aircraft take-off. Goddard learned of this in 1940, and openly expressed his displeasure.[84] Malina could not understand why the Army did not arrange for an exchange of information between Goddard and Caltech, since both were under government contract at the same time. Goddard did not think he could be of that much help to Caltech because they were designing rockets with solid fuel and Goddard was using liquid fuels.
Goddard was concerned with avoiding the public criticism and ridicule he had faced in the 1920s, which he believed had harmed his professional reputation. Goddard also lacked interest in discussions with people who had less understanding of rocketry than he did,[85] feeling that his time was extremely constrained.[86] Goddard's health was frequently poor, as a result of his earlier bout of tuberculosis, and he was uncertain about how long he had to live. He felt, therefore, that he hadn't the time to spare arguing with other scientists and the press about his new field of research or helping all the amateur rocketeers who wrote to him.[87]
Goddard spoke to professional groups, published articles and papers and patented his ideas; but while he discussed basic principles, he was unwilling to reveal the details of his designs until he had flown rockets to high altitudes and thus proven his theory.[88] Goddard tended to avoid any mention of space flight, and spoke only of high altitude research, since he believed that other scientists regarded the subject as unscientific.[89]
During the First and Second World Wars, Goddard offered his services, patents and technology to the military and made some significant contributions. Several young Army officers and some higher ranking ones believed Goddard's research was important, but were unable to generate funds for his work.[40]
Toward the end of his life, Goddard, realizing he was no longer going to be able to make significant progress alone in his field, joined the American Rocket Society, became a director, and made plans to work in the budding aerospace industry.
Goddard was diagnosed with throat cancer in 1945, and died in August of that year in Baltimore, Maryland. He was buried in Hope Cemetery in his home town of Worcester, Massachusetts.[90]
The Guggenheim Foundation and Goddard's estate filed suit in 1951 against the U.S. government for prior infringement of Goddard's work. In 1960, the parties settled the suit, and the U.S. armed forces and NASA paid out an award of $1 million (half went to his wife), at that time the highest government settlement ever paid in a patent case.[91]
The settlement amount was more than the total of all the grants disbursed for Goddard's work over his career.
Goddard was credited with 214 patents for his work; 131 of these were awarded after his death.[92]
The Goddard Space Flight Center, a NASA facility in Maryland, was established in 1959. The crater Goddard on the Moon is also named in his honor.
On Sept. 16, 1959, the U.S. Congress authorized the issuance of a gold medal in the honor of Professor Robert H. Goddard.[12]
The Dr. Robert H. Goddard Collection and the Robert Goddard Exhibition Room are housed in the Archives and Special Collections area of Clark University's Robert H. Goddard Library. Outside the library lies a structure depicting the flight path of Goddard's first liquid fuel rocket.
The Chemical Engineering department at Worcester Polytechnic Institute is housed in Goddard Hall.
Goddard's home town of Worcester established the Goddard School of Science and Technology, an elementary school, in 1992. Robert H. Goddard High School was completed in 1965 in Roswell, New Mexico and dedicated by Esther Goddard; the school's mascot is appropriately titled "Rockets".
The Civil Air Patrol Cadet Program Goddard Achievement, corresponding to promotion to Cadet Chief Master Sergeant is named for him.
A small memorial with a statue of Goddard is located at the site where Goddard launched the first liquid-propelled rocket, now the Pakachoag golf course in Auburn, Massachusetts.
Goddard Auditorium is located on the Earlham College campus in Richmond, Indiana.
The problem of optimizing the altitude of a rocket under atmospheric drag and gravity is referred to as the Goddard problem.
On June 21, 1924, Goddard married Esther Christine Kisk, a secretary in Clark University's President's office, whom he met in 1919. She had photographed some of his work as well as aided him in his experiments and paperwork, including accounting. After his death, she sorted out Goddard’s papers and secured 131 additional patents on his work. The couple did not have children.[93]
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