Breaking the Star Barrier
Only a half century after the first flights of the Wright brothers, U.S. Naval aviation has produced a giant rochet which attained a speed of neartv 5000 m.p.h. and an altitude of 158 miles. Animals have survived in good condition rochet ascents of 65 miles, and a piloted aircraft has traveled in level flight at 1600 m.p.h. — almost two and one-half limes the speed of sound. If the next half century brings comparable progress, many authorities expect that travel in outer span* will become a reality. A journalist of long experience in automotive and engineering subjects, LLOYD MALLAN recently gave up editorial work in order to devote his time to writing.
by LLOYD MALLAN
1
THE Navy’s energetic research program and successful developments in rocketry today are steadily clearing the way to space flight. Highranking Naval officers of the old school are scornful of the idea. They insist that the Navy is interested only in earth-bound objectives: the mathematical curve that a missile must travel in order to strike a target dead-center is the inspiration behind every supersonic achievement, they say. But they are executive officers, not rocket men. The Navy’s roekel scientists discuss the problems of space travel with a dollars-and-cents seriousness. Their motivating question is not “Can it be done?” but “How much will it cost if done most efficiently?”
Almost every important rocket development of the military services can be traced directly or indirectly to Navy stimulation. It was a Navyinspired rocket engine, for example, that blasted the Bell X-1, an Air Force research plane, through the sound barrier for the first time in level flight. The WAC-Corporal, a second-stage rocket that shot 250 miles right up to the edge of outer space, was a project of the Army Ordnance Department; yet the Navy helped to finance the military and civilian agencies involved, and the Naval Research Laboratory was at that time in charge of coordinating all upper-air research in the I nited States.
The latest spectacular accomplishment of the Air Force can also be traced to Naval research in rocketry. On December 12 last year, the X-1A broke all speed records for piloted aircraft by traveling at over 1000 m.p.h.—almost two and a half times the speed of sound. Built by Bell Aircraft Corporation, it was a sister ship to the X-1 and was powered by the same type of Navydeveloped engine.
The development of rockets has been amazingly rapid. Only thirteen years ago a small group of Naval scientists and engineers began to experiment with single-nozzle solid-fuel rockets and conventional aircraft. The purpose was to speed up a plane’s take-off by adding rocket power to get it off the ground. If the system were perfected, fighter planes could be launched from aircraft carriers that were not equipped with catapults, and more plant’s could bo carried aboard, since valuable deck space normally taken up by runways would be used for storage.
During these early experiments a comparatively unknown junior officer risked his neck time and again to collect practical information on the action of rockets during a plane’s take-off. He is C. Fink Fischer, at present a full commander in the Bureau of Aeronautics; but when be offered to pilot dozens of unpredictable test flights, he was a lieutenant j.g. His ingenuity supplied the Navy with a solution to many of t he engineering problems in rocketry, and he later worked out the specifications for the rocket engine that now powers the record-shattering Bell and Douglas research aircraft.
The first ground-to-air test was rather hard on Fischer— and the plane. A small rocket was mounted under the fuselage of a Wildcat lighter. The plane taxied to the edge of the runway and started to move under its own gasoline power. Then t he rocket was cut in. A great sword of orange flame slabbed out toward the ground, and the plane bucked like a mad horse. A moment later, huge billows of white smoke obscured 1 he flame, and the plane leaped shakily into the air. The controls were not designed to handle, the tremendous power of the rocket thrust, nor was the fuselage able to take the terrific temperatures. Fischer somehow managed to land safely beyond the far end of the runway — stopping his craft just before it would have tumbled into a river. When the plane landed, all fabric had been burned away lrom the tail assembly.
Mure and more small rockets wore added in succeeding flights, unlil the plane literally shot into the air lroin a standing position. Although the blasting heal of the rocket series melted most of the metal in the plane’s rear, all these experimental flights were considered successful because (hey supplied the rocket men with important information on methods of handling, installing, and servicing equipment. The men kept working to improve their techniques and rockets. They continued to try different types of aircraft. This was in 1941. There were fewer than 60 persons involved in the project, including maintenance crews and assorted technicians, A year later, judgment day was scheduled. William L. Gore, one of the technical officers, defined it neatly: “This was the big moment, father we’d nominee the Admiral of our value and gel a nice appropriation, or else we’d be out in t he cold.”
According to Gore, everybody got up at four o’clock in the morning to double-check all equipment. “We couldn’t get the equipment to work,” he said. “We tried for two and a half hours to locate the trouble and almost decided to build a new unit on the spot —which would have been impossible, of course. Maybe it was sheer will power, but we finally got the rocket shipshape just before the Admiral in charge of aviat ion policy arrived.”
As it was, Admiral McCain stood by to watch a heavily loaded plane rise swiftly into the air spewing twin jets of flame from the two assist rockels. It leaped toward the sky hundreds of feet earlier than it would have if propelled only by its own power. “We must have that on all our fighter planes,” said the Admiral laconically after the test.
2
As a midshipman, Robert C. Truax had specialized in mechanical engineering at Annapolis from 1986 to 1989, and had begun to develop a rocket engine in his spare time. He had been inspired by some of the experiments accomplished in the American Rocket Society with liquid-propellant engines. Most successful engines of t his kind lista main fuel and another liquid to oxidize the fuel for ignition. So Midshipman Truax needed some liquid oxygen. But there was a hard rule in the engineering department: no oxygen of any kind was allowed because of the preponderance of oil in the laboratory. A drop of liquid oxygen mixed with oil would cause an instantaneous fire. After much red tape and argument, culminating in a flat refusal by the industrial engineer, the young midshipman — he was about twenty then — decided to see the Admiral in charge of the Nasal Engineering Experiment Station at Annapolis.
This was an unprecedented act of brashness. The high officer was stern. “You certainly must understand our reason for the rule,” he said. “It’s a safety measure. You simply cannot mix liquid oxygen with oil.” The midshipman was polite but linn. “Yes, Admiral,” he answered. “Rut 1 don’t want to mix it with oil. I want to mix it with gasoline.”
Midshipman Truax got his liquid oxygen because Rear Admiral Cox was so startled by the answer that he was thrown off guard. Gasoline and oxygen are a much more explosive combination than oil and oxygen.
When the midshipman became an ensign and went to sea for a tour of duty, lie tried to lest his engine aboard the Enterprise, where he made use of the aircraft carrier’s machine shop to build a lest stand. The odds were against him this time; be wasn’t permitted to fool with rockets aboard ship. Bill at least he had accomplished something; Inowned a test stand. So Inwaited patiently and later tried out his engine ashore. He devised an engine that was more efficient than all previous ones for this purpose. It was the first liquidfuel rocket to be applied successfully to Naval aircraft. Again he stuck his neck out. lie walked in cold on the appropriations officer and asked for $65,000 to develop his new engine. The officer amazed him by agreeing. Il seemed like a lot of money to the ensign. It was not fling compared w it h the lives it indirectly saved in the South Pacific.
Although liquid-fuel engines were never used operationally by the Navy in assist take-offs, they provided an important experimental step along 1 tawny toward development of practical assist rockets.
One of the first tests of the “Truax spherical motor” was made on a PRY flying boat with a pay load two tons heavier than any ever carried before. It rose off the choppy water in good shape and soared above its streaming smoke clouds to prove that an efficient rocket engine is not all science fiction. Later engines developed by the Aerojet General Corporation made it possible for pilots to take off under extremely difficult conditions in the Pacific Islands, where take-offs were often hazardous, if not impossible, under ordinary power conditions.
But JATO (Jet-Assist-Take-off) units were only a beginning. Almost simultaneously with “Project JATO” tinNavy was branching out into the field of larger and better rockets. One of these engines is the 6000-pound-thrust engine which [lowered the Bell X-1, the X-1A, and the Douglas D558-II Skyrocket.
The project I hat led to the development of the Douglas Skyrocket was begun in April, 1945, when ihe Navy gave Douglas Aircraft Company engineers a set of specifications and asked them to go to work. The plans required a straight-wing turbojetpowered piano for research use at velocities approaching and reaching the speed of sound. The D558-1 Skystreak was completed and tested exactly two years later. Almost immediately it began to establish new world air speed records in the range between 640 and 650 m.p.h. Out of Sky streak tests came information that made possible the design of a swept-wing, needle-nosed ship with rocket power.
The Douglas Skyrocket first flew on February 4, 1048. By t he following year il had made 138 ground take-off flights, regularly exceeding the speed of sound and reaching 40,000-foot altitudes. “In 1040, ihis was quite a feat,” said a Douglas official recently. In 1053 the Skyrocket reached twice the speed of sound and climbed 83,000 feet into the stratosphere. According to Naval officers in the know, current records can be expected to be doubled in loss than five years.
In addition, the Navy has a financial interest in the Air Force X-3, a turbojet research plane designed specifically to hit Mach 3, or three times the speed of sound. Although it has not to date reached this speed, Douglas engineers are certain that it will if properly powered. The engines for which it was originally designed have proved too bulky in physical size to fit into the narrow jet pods of the projectile-shaped craft. In appearance, il is the closest thing to a spaceship existing today. Because of its stubby wings it requires a take-off run of about 3 miles.
The earliest Skyrocket version took off quickly with JATO units. Another version was dropped from the belly of a B-29, again using assist units to start it off. The latest version is dropped from a B-29 and roars away upward, fully under its own rocket engine power.
The man who first flew this latter version of the D558-II was William Bridgeman. He kept up a running commentary by radio as the plane shot away on its four rockets. “It feels as il I’m on my back looking straight up,” he said. “I pick a spot in the sky and 1 imagine I’m going right on through a hole, out of the earth’s orbit.”
Bridgeman is noted for his coolness and keen judgment under extreme conditions. Yet his radioed statements indicate that, at least in a small way, this aircraft was acting like a spaceship. The Navy really started something with the Skyrocket.
The motivating reason for development of the Skystreak and Skyrocket research planes was a simple aerodynamic fact: existing planes were reaching subsonic and transonic speed’s in power dives, but no informal ion could be collected because of the very short duration of the dive. Such information could be gathered only in horizontal flight.
More than 8500 reports have been given ihe industry and the military services on D558 tests, making possible the standardized production of today’s supersonic military aircraft.
3
THE tremendous achievements in rocketry would have been impossible were it not for a small group of “ordinary” American citizens who dedicated their weekends and holidays to the pursuit of a fantastic hobby. Some of the now retired old1 inters of the New Jersey Slate Police must si ill remember Edward Pend ray, John Shesta, Franklin Pierce, Lovell Lawrence, Jr., Bernard Smith, and the late James Wyld. During the 1930s they chased these men all over the Jersey countryside because of complaints resulting from rocket tests. Scouting about in cars loaded down with instruments to check on their newest rocket engine, the men would locate what they felt was a safe, isolated spot. They would pull up, dig a series of trenches for selfprotection, place their rocket test stand beyond, and duck to cover while the rocket fired. But the tremendous noise of even a small rocket disturbs people a mile or more away. So the police came, and the men moved on.
These were the early members of the American Rocket Society, founded in March, 1930, by Ed Pendray. What they lacked in funds and facilities, they compensated for with enthusiasm and hope. By 1940 they had made many notable contributions to rocket engine design and technology. Chief among these but growing out of the others — was the Wyld regenerative engine.
It was the lirsl successful American power unit of its kind as well as the second practical rocket engine in t he world. The solut ion to its construct ion it p pea red on Wyld’s drawing board and mechanical tests were made in 1938, only a short time after German rocket groups, working with militarystimulated intensity, solved the same problem. The difference was that the Germans, scorning costs, immediately set up a huge rocket experimental base at Peencmiinde on the Baltic Sea, where hundreds of workers and scientists labored to create the big engine that eventually powered the destructive Y-2. Wyld, on the other hand, had to wait almost three years for official encouragement in developmental work because of limited E.S. government research budgets. Then it took a declaration of war to get him started.
His little engine was about 8 inches long and weighed less than 5 pounds. It was power rated at 100 pounds of thrust, or what would be equivalent to 100 horsepower at half the speed of sound. Its most important feature was the cooling system; the fuel before exploding in the firing chamber was used to cool both chamber and nozzle walls by circulation, thus making possible an efficient engine of minimum weight that would not melt under the terrifically high temperatures involved in continuous explosion. The engines powering the Bell X-l and X-1A as well as the Douglas Skyrocket and the huge Navy Viking research rocket today are essentially the same in basic detail as this small one.
When America declared war against Germany late in 1941, officers of the Naval Bureau of Aeronautics — who were aware of Wyld’s tiny engine — asked permission to run a series of tests on it. Commander Fischer supervised the tests. It was his enthusiasm for the engine, coupled with lus advice regarding improvements, that hastened the awarding of a developmental contract. Together with Wyld, three other members of the American Rocket Society — Shesla, Lawrence, and Pierce — founded a company. Those men pooled a total of $5000 in savings plus their engine development ideas a week before Christmas, 1941, and began immediate work on the Navy contract in the basement of Shesta’s home.
They incorporated their new firm and christened it Reaction Motors, Inc., after the manner in which a rocket works: the amount of action created by fuel explosion causes an equal amount of reaction (or push) against the inside of the engine, thereby propelling it forward or upward. This kind of propulsion, plus the unique fact that a rocket engine carries its own fuel-oxidizing agent, makes it possible for it to move through the most rarefied atmosphere or even a vacuum. All other engines, including the various jet types, need outside air to create fuel combustion.
Not long after its founding, Reaction Motors, Inc., moved from its cellar shop to a small garage in Pompton Plains, N.J., where, within a period of nine months, production amounted to a series of six experimental engines, ranging in power from 50 to 1000 pounds of thrust. The only employees of the company at this time were its four founders. Finally they developed a 3000-pound-thrust JATO rocket unit that was practical for Navy use. It was fitted out successfully on the Martin PBM Hying boat in 1943. Just previous to this they were able to hire some outside help for its production.
During the following year and a half the staff was expanded and Reaction Motors produced two more rocket engines for the Navy: a 350-poundthrust unit was developed in forty-five days, with the personal help of Commander Truax, to power the Gorgon guided missile, and a 620-pound-thrust rocket was created with Navy technical aid to propel the Lark subsonic missile, built by the Fairchild and Convair aircraft companies.
In 1946, the first of a series of four-nozzle, 6000pottnd-t hrust engines was perfected. A direct descendant of the little Wyld regenerative engine, this much larger one was designed specifically for piloted aircraft. It was this engine which made history in October, 1947, by sending the Air Force Bell X-l through the sonic barrier in level flight.
With the successful Series 6000 engine, other problems were resolved. Laurence S. Rockefeller invested a considerable amount of money in the firm, and the Navy provided several buildings and isolated ground test facilities at its ammunition depot in Lake Denmark, N.J. Soon afterward, the Naval Aeronautical Rocket Laboratory was set up in adjoining buildings. Both the Navy and Reaction Motors wore now working hand in glove to perfect bigger and better rocket engines.
By April, 1950, work had expanded to the point of reorganization. The ammunition depot had shrunk in usefulness as compared with rocket research. Most of the buildings were now occupied by Reaction Motors and Navy rocket scientists. The Rocket Laboratory had been renamed the Naval Air Rocket Test Station. Facilities of the stalion are today available to any manufacturer desirous of engaging in rocket engine research, subject to the approval of the Bureau of Aeronautics.
In terms of personnel, the station is probably the smallest big operation in the entire Navy. There are fewer than 20 officers and 200 enlisted men; civilian scientists and technicians number about 200 also. But work at the station is so specialized and concentrated that results suggest a staff equivalent to the crews of several battleships. For example, ground tests of rocket engines are continually being made for all the military services as well as for various Defense Department contractors. There is a continuous research into the development of new’ rocket fuels. In addition, the fuels are tested for safety in handling.
There are test stands of heavily reinforced concrete everywhere, but lording it above them all is (he giant stand atop a high hill in tlie Reaction Motors area. It’s the largest stand in the eastern knifed States and is overshadowed only by the bigger giants at White Sands Proving Ground in New Mexico and the research center at Muroc, California. Built over a year ago by the Navy, after a year in designing, the number and sizes of engines tested in this stand are both classified. It is sufficient to point out that the stand was designed to accommodate rockets up to 350,000 pounds of thrust—a power rating about six times that of the Y-2 engine.
4
IN THIS age of rocketry and jet propulsion the designations “horsepower” and “miles per hour" have become obsolete. The power of a rocket varies with its speed, and its speed depends on the amount of fuel it can carry for prolonged propulsion. At 350.5 m.p.h., horsepower is equivalent to pounds of thrust. Rocket horsepower would automatically increase from this speed onward in direct ratio to the acceleration. The latest 6000-poundthrust engine, now powering the Douglas Skyrocket, would be equal to 6000 horsepower at 350 m.p.h. But the plane has traveled about four times as fast as this, and at such a speed its engine has developed a power equal to about 23,000 horses.
Even more awesome are the horsepower figures of huge unmanned rockets like the German V-2 and the Navy’s Viking. The V-2 has traveled at roughly 4000 m.p.h. with its 56,000-pound-thrust engine; the Viking has hit nearly 5000 m.p.h. with a Reaction Motors engine of 20,000 pounds thrust. At top speed, the former developed some 650,000 horsepower, and the latter about 286,000 horsepower.
Unquestionably, the Navy is experimenting with larger projectiles than the Viking — which, according to the released facts, today holds the world’s speed and altitude records for single-stage rockets. It is more efficient than the larger V-2, from which it was developed. The Viking has shot straight up to a height of 158 miles, outclimbing the V-2 by 22 miles, with one third the power.
According to theory, a rocket engine ot whatever size — large or small — is capable of unlimited speeds. The tiny Wyld engine as well as the big Viking could be accelerated out of the earths gravitational grip and shot off into outer space, provided each could carry enough fuel to power it long enough to reach a speed of 25,000 m.p.h.
Although a rocket engine is incredibly light in relation to its rated power, there is always the problem of fuel weight. The 6000-pound-thrust, engine mentioned earlier burns up a ton of fuel every minute, although it weighs only 210 pounds. Admittedly a serious problem, the weight of fuel has nevertheless not prevented a rapid progress in rocketry. New fuel combinations are always being tried. There is also a considerable interest in atomic-powered rockets. If such a rocket could be developed, the question of fuel weight would vanish. There would be no limit to speed possibilities; a trip to the moon would be an elementary venture.
Regardless of the problems, the Air Force, using Navy rockets, has been carrying out spectacular medical tests on animals. Two while mice were shot lo a height of 40 miles and two rhesus monkeys to a height of 65 miles in Aerobee rockets. Information released officially in September, 1952, stated that the flights “provided information on the reactions of mammals under conditions of zero gravity and extreme altitude. The mammals . . . were recovered alive and in good health after the test. . . . The Air Research and Development Command has concluded that it is possible for a mammal to function within the range of normalcy during t he rocket flight.”
Although this official report may lead one to believe that the two tests were unique, the fact is that an extended series of such tests has been carried out in the New Mexico desert. Total developmental costs of the Aerobee were under $200,000. About 200 of the rockets have been produced by the Aerojet General Corporation of Azusa, California. They have been sold at a lowcost (for rockets) of $15,000 each to all branches of the military and have been used in a multitude of upper-air research projects. Mith aniline as a fuel and nitric acid as oxidizer, fuel costs ol the Aerobee are also low — about $100 per flight.
It was the Navy’s idea to develop a versatile rocket that could be used at minimum cost. Funds and specifications were offered to the Applied Physics Laboratory of Johns Hopkins I’niversity, which accepted the project and successfully completed it in record time.
The accomplishments in rocketry to date provide a solid foundation on which to build for the future. The current reduction in defense budgets must not be used as an occasion to eliminate what may appear to be “fantastic” long-range developments. Every stupendous step forward in the history of man has resulted from planning with courage and vision. The Aerobee is only one more link in the long chain that is stretching toward the moon.
