would be supplied from an upper reservoir and would be injected into or downstream of the exhaust nozzle to reduce the temperature of the gases emanating from the gaseous nuclear rocket. If oxygen were burned with the hydrogen propellant, the exhaust stream would consist entirely of water and fission products. Studies indicate that these fission products would be completely soluble in the exhaust water. Following completion of an engine test, the water would be pumped back from the lower pond to the upper pond through a separator which would be employed to remove fission products and any unburned fuel. The use of such a facility would permit engine tests at reasonable cost without contamination of the atmosphere by fission products. For this initial demonstration and proof of the gaseous-core nuclear rocket principle, it may be expedient to utilize water as the working fluid in order to minimize fuel and facility costs and eliminate the desirability of oxygen addition. CLOSING STATEMENT In conclusion, it is apparent that economic limitations will inhibit future largescale manned operations in space unless a propulsion system is developed which will provide specific impulses in excess of 2,000 seconds with thrust-to-weight ratios on the order of 10 or 20 to 1. The only prospect which we foresee for the fulfillment of these requirements and which can be developed in ground tests is the gaseous-core nuclear rocket. Under the program which has been in progress at the United Aircraft Corp. Research Laboratories during the past 5 years, truly significant accomplishments have been made in the solution of the imposing problems associated with the containment of a gaseous fissioning fuel and in the transfer of heat to a light working fluid. No serious obstacles have been encountered which would discourage continued and accelerated support of this effort. In consideration of the extreme performance potential of this device and the unquestionable need for such an advanced propulsion system should the current trend in space activities continue in future decades, this Nation cannot afford to neglect this opportunity for advancing nuclear propulsion technology. However, because of the problems which remain to be overcome, the gaseous-core nuclear rocket must be considered at the present time as a somewhat speculative device, and its ultimate development could not conceivably occur until after the next decade. In the meantime, it is hoped that efforts on solid-core nuclear rockets and high-pressure chemical rockets will be actively pursued to fulfill intermediate requirements for space propulsion. The technologies developed under these latter rocket program in the areas of metallurgy, high-temperature heat transfer, highpressure propellant pumps, and nucleonics are essential to fulfillment of the more distant objectives in propulsion as afforded by the gaseous-core nuclear rocket. Mr. TEAGUE. Thank you, Mr. McLafferty. The committee will be adjourned until 2 o'clock in executive session. (The prepared statement of Dr. W. E. Johnson is as follows:) PREPARED STATEMENT OF DR. W. E. JOHNSON, GENERAL MANAGER, ASTRONUCLEAR LABORATORY, WESTINGHOUSE CORP. I am Dr. Woodrow E. Johnson, general manager of the Westinghouse Astro nuclear Laboratory and project manager of our portion of the NERVA project. It is a privilege to appear before you and present Westinghouse views on the role of the nuclear rockets in the Nation's space program. We believe the development of a nuclear rocket is in the national interest. The program, as it stands today, is well conceived and promises technica success. The activities of the Astronuclear Laboratory are directed toward the appli cation of nuclear power in outer space. Our major activity is in the NERVA program. As many of you are aware, we were selected about 3 years ago as the engineering development contractor for the reactor portion of the nuclea rocket engine. About 1,600 Westinghouse employees are now directly or indi rectly working on this project; 1,500 of these are at the laboratory in large, an about 100 are stationed at the Nevada test site. Our work on the NERVA program is done under a subcontract with Aerojet General, the prime contractor for development of the entire engine. All of thi work is conducted under the management of the Joint AEC-NASA Space Nuclea Propulsion Office. Because of our broad experience in the field of nuclear technology, we were particularly interested in becoming associated with the nuclear aspects of the space program. Our experience includes the continuing development of reactors for naval propulsion-starting with the Nautilus-as well as the development of power reactors for the utility industry, such as Shippingport, Yankee, and many others. Development of a well-engineered, reliable, and practical nuclear reactor for any application is a tough technical job. It cannot be done in a matter of months, but rather it requires continuous and orderly development over a period of years. The application of nuclear power to rocket propulsion is no exception. In fact, because of the high demands placed on it, the nuclear rocket reactor is as difficult a job of reactor development as anyone has undertaken to date. At full power the reactor will produce more heat than any nuclear powerplant operating today; yet, in size it is among the smallest of reactors. The operating temperature must be over twice that of any reactor operating today. Although many different technologies have been explored for employing nuclear power in rocket propulsion, the most attractive thus far is the solidcore hydrogen-cooled unit, employing uranium-bearing graphite as the reactor structural material. This system was under development at the Los Alamos Scientific Laboratory for several years and led to the Kiwi group of reactors and reactor tests. The basic nuclear design and materials incorporated in this system permits much of the reactor development knowledge and experience of the Nation to be directly applied to the program. As the starting point in the design and development of a flight-type reactor, the Space Nuclear Propulsion Office called for an exhaustive review of the various designs prepared by Los Alamos. The Kiwi B-4 became the preferred basic design since it capitalized to a maximum extent on the accumulated experience. While Los Alamos proceeded with the initial version, leading to the Kiwi tests, our Astronuclear Laboratory undertook redesign to incorporate flight-type requirements. These programs of Los Alamos and Astronuclear have paid big dividends through a two-way exchange of information as design and test work proceeded. The technical problems in this reactor system can be broadly grouped into three categories: (1) Structural design; (2) Fuel development; and (3) Nuclear and thermal design. Major progress has been made in all three of these areas. Mechanical design From the beginning of the program, it was evident that mechanical design would be a major problem. A structure which can withstand rapid changes in temperature-from low liquid hydrogen temperatures up to the high temperature of gas emanating from the nozzle-requires much detailed study. This requirement was emphasized late in 1962 when the Kiwi B-4A reactor test indicated a severe vibration problem within the core. Although potential solutions were already manifesting themselves, at the time of the tests, the Space Nuclear Propulsion Office decided to undertake an aggressive analytical and experimental program to insure that this problem would not occur in later tests. The NERVA reactor, designated the "NRX-A," was redesigned on the basis of information gained from these experiments and the design was thoroughly analyzed during 1963. Experiments with components were undertaken to estab lish all the design features before large-scale tests were undertaken. Wherever possible, reactor components were subjected to the environmental conditions they would experience within the operating reactor. Success of this program was indicated by the successful cold flow tests performed on the NRX-A1 reactor in Nevada on March 5 and March 11, 1964, and which are continuing. The tests verified the essential correctness of the careful design work which is required to assure stability and structural integrity under the startup conditions of the reactor. Fuel development The principal design requirements for the nuclear fuel can be summarized as: (1) Uranium-bearing graphite in nuclear optimized proportions; (2) Sufficient area to allow the required heat transfer to the hydrogen, yet retaining enough structure to maintain structural integrity; and (3) Adequate resistance to high temperature, high velocity hydrogen corrosion. The development of a satisfactory nuclear fuel is a continuing program for any type of reactor. Initially the fuel must meet minimum requirements. It must then be steadily and continuously improved to meet higher and higher operational demands. The development of the Kiwi and NRX-A fuel has just about reached the region of minimum demand. Much work yet remains before it can be said that a fully satisfactory fuel has been developed for future demands. Real progress is being made, however, and it appears that today's basic concept can be expanded to meet all future requirements. Nuclear and thermal design The nuclear and thermal design problems are also well on the way to being solved. The first fueled core of the NRX-A design has been undergoing criticality and other nuclear tests at the Westinghouse reactor test facility at Waltz Mills, Pa. The initial criticality experiment proved out within 1 percent of the total required loading of uranium. This is a major technical achievement for a reactor as advanced in concept as the NRX-A. The nuclear and thermal transients imposed on this design have required extensive laboratory tests. These tests subjected components, subassemblies, and assemblies to as many of the operational factors as could be simulated in the laboratory. As a result, solutions have been found. The program can now confidently direct its attention to problems of high temperature, high heat flux, and to nuclear operation. The cold tests now underway in Nevada have proven the mechanical design. The total NRX-A design, however, can be evaluated only by a thorough nuclear test operation of the reactor. The first of these is scheduled for August of this year. The components and fuel for this test reactor are now being manufactured and assembled, and the will be shipped to Nevada in June. Only when the hot test has been successfully completed will we be confident that we have satisfactorily solved the basic problems. This must be done not once but many times, in order to be confident that we not only have a solution but a solution which will be substantiated time after time in space applications. In closing, let me say Westinghouse is convinced that nuclear rockets are indispensable to space propulsion, for the 1970's and beyond. From our experience to date, we believe that the NERVA program, based on a solid-core hydrogen-cooled reactor, will be successful. We feel that substantial progress has been made, no little part of which has been due to the technical management of the project by joint AEC-NASA Space Nuclear Propulsion Office. We are confident that the nuclear tests to be carried out during the remainder of this year will be as successful as the cold test, and that 1964 will be the success year of a nuclear rocket program. Thank you, Mr. Chairman. CHEMICAL PROPULSION THURSDAY, MARCH 19, 1964 HOUSE OF REPRESENTATIVES, COMMITTEE ON SCIENCE AND ASTRONAUTICS, SUBCOMMITTEE ON NASA OVERSIGHT, Washington, D.C. The subcommittee met at 2 p.m., in room 214-B, Longworth House Office Building, Hon. Joseph E. Karth presiding. Mr. KARTH. The meeting will be in order. I assume a quorum is present. Hearing nothing to the contrary, a quorum is present. Let me first of all apologize to the witnesses. There are quite a number of rollcall votes and quorum calls going on this afternoon which was not previously known to us, so we must apologize for breaking away so often as we have in delaying the meeting. I understand that it has been suggested by the staff that each of the witnesses today give an 8-minute summary of their statement. And then there may be some questions on the part of the counsel or the members of the subcommittee and we will begin in alphabetical order with Dr. Kirchner, who is the vice president and general manager of the solid rocket plant at Aerojet-General. Dr. Kirchner, are you prepared to proceed at this point? Before I proceed I would like to introduce Dr. Ross, who is our corporate vice president of engineering. And Dr. Moise, who is our assistant program manager of the M-1 program in Sacramento. I have a prepared statement here which I would like to leave. I am not going to read it. Mr. KARTH. If there are no objections, Doctor, it will become a part of the record and you may summarize your prepared statement. (The prepared statement of Dr. Kirchner is as follows:) PREPARED STATEMENT BY DR. WERNER R. KIRCHNER, VICE PRESIDENT, AEROJETGENERAL CORP. CHEMICAL ROCKET PROPULSION ADVANCED TECHNOLOGY I would like to present the viewpoint of Aerojet-General Corp. concerning several pertinent areas of consideration in space chemical propulsion. I would like to review propellants and propulsion concepts based on requirements of each stage of a space vehicle, discussing current state of the art, near-term advances in state of the art, and longer term potential advances, and conclude with some recommendations. The discussion will involve both propellants and engine features with emphasis on programs such as the M-1, the 260-inch solid rocket and the high-pressure feasibility work which relate to these questions. |