1963 NASA AUTHORIZATION

TUESDAY, APRIL 3, 1962

HOUSE OF REPRESENTATIVES,

COMMITTEE ON SCIENCE AND ASTRONAUTICS,

SUBCOMMITTEE ON ADVANCED RESEARCH AND TECHNOLOGY,

Washington, D.C.

The subcommittee met at 10 a.m., Hon. Victor L. Anfuso (member of the subcommittee) presiding.

Mr. ANFUSO. This meeting will come to order.

Today we are holding our last hearing with the Space Propulsion industries. We have heard from the Hercules Powder Co., United Technology Corp., Aerojet-General Corp., and the Lockheed Propulsion Corp.

This morning I want to welcome first Dr. H. W. Ritchey, vice president for rocket operations of the Thiokol Chemical Corp., and following him at 11 o'clock, Mr. George P. Sutton, manager of the long-range planning, and Mr. William Hines, vice president of Rocketdyne division of the North American Aviation Corp.

It gives me great pleasure to welcome these outstanding representatives of American industry on behalf of all the members of the committee.

Gentlemen, as you know, the purpose of these hearings is to review NASA's 1963 program in the fields of advanced research and technology. During recent testimony taken before this subcommittee a number of witnesses have expressed conflicting views regarding the ability of solid propulsion systems to compete with our liquid systems in the space exploration program. Therefore, we have asked representatives from the solid fuel propulsion industry to testify before the committee in order that we may learn what industry feels they can achieve in the field of solid propulsion if given an opportunity to execute a properly funded development program. I understand, gentlemen, that you both have prepared statements which I am going to ask you to submit for the record and give the committee an oral summary of your prepared statement, after which time we will proceed with the questioning.

Dr. Ritchey, I understand that your statement is classified and therefore you will give it to the committee for the file and that you are ready to give us an unclassified oral statement?

Dr. RITCHEY. Yes, sir.

(Biographical sketch of Dr. Harold W. Ritchey follows:)

DR. HAROLD W. RITCHEY, VICE PRESIDENT, THIOKOL CHEMICAL CORP., BRISTOL, PA. A pioneer in solid-propellant rocketry, Dr. Ritchey has guided the development programs for Thiokol Chemical Corp., rocket operations since June 1949.

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He earned a bachelor of science degree in chemical engineering in 1934, a master of science degree in physical chemistry in 1936 and a doctorate in physical chemistry in 1938, all from Purdue University; and a master of science degree in chemical engineering from Cornell University in 1945. In addition to his duties as vice president, Rocket Operations, Dr. Ritchey serves Thiokol as a member of its board of directors.

Dr. Ritchey has contributed to numerous publications and holds several patents in the fields of rocketry, astronautics, nuclear reactor technology, and in the petroleum industry.

In 1934, he was elected to Phi Lambda Upsilon, national chemical and chemical engineering honorary society; and to Sigma Xi, national research honorary society. In 1954, he received the C. N. Hickman Award of the American Rocket Society for his outstanding contributions to the field of solid-propellant rocketry. He was elected president of the American Rocket Society and served in that capacity during the calendar year of 1961. He is also a member of the American Chemical Society, the Institute of Aerospace Sciences, and the American Ordnance Association.

From 1941 to 1946, he served in the U.S. Navy. A portion of this time was spent at the U.S. Naval Postgraduate School where he taught courses in chemistry, chemical engineering, and the mechanics and thermodynamics of jet propulsion and rocketry.

In addition to Dr. Ritchey's experience in the rocket propulsion industry, he has worked in the petroleum industry and in the field of nuclear reactor technology.

STATEMENT OF DR. HAROLD W. RITCHEY, VICE PRESIDENT, THIOKOL CHEMICAL CORP., BRISTOL, PA.

Dr. RITCHEY. Mr. Chairman and gentlemen, we felt that your request for information regarding fruitful areas for research and development was indeed a very appropriate one.

We regret that we were not able to submit what we felt was a meaningful complete coverage of this field without going into classified information since many of the areas that seem to be appropriate for research and development efforts do constitute areas that are classified and the coverage of these areas has to be placed under security classification.

In preparing this particular statement, I would like to point out that we have made extensive use of what we feel is still a very appro priate and currently valid document, a document prepared in an ad hoc committee convened by the Department of Defense approximately 2 years ago, chairmaned by Mr. Tom Dixon who was then vice president of the Rocketdyne division of North American Aviation.

We abstracted much of the information in this report and presented it in a form where we felt it would be more applicable to the particular areas of space exploration. This report is available under a security classification of confidential and will be submitted to the committee through the proper channels and proper procedures.

We feel in particular that attending to the areas of research and development is a very important activity. I seem to note occasionally a sort of imaginable type of velocity. You seem to convert it to end item application and then lean back in the chair and say, "Well, I have done it; now I can relax."

This is not true. Technology is a continually expanding area of endeavor. Every time you answer one question regarding the laws of nature, you open up many, many more, and never ceasing efforts which are required in the areas of basic research, applied research, and development.

This is essential not only to survival against the vicissitudes of hostility of nature, but also survival as a nation against our potential enemies.

From this point on, in order to make the remainder of the session unclassified, I would like to do my best to put in proper perspective this question of solid rocket fuel propulsion and liquid rocket fuel propulsion.

This has been a very controversial issue and one of the reasons is because it is so difficult to compare the two systems. It is even worse in some cases than the job of comparing apples and oranges. In making this comparison today in trying to make the application to two different systems in the proper perspective, I would like to talk about the turbopump liquid rocket. It is a system whereby you have two fuel components contained in two separate tanks, one the oxygen and the other sometimes called fuel. The rockets we are applying today at least most of them in this particular type of technologyuse a petroleum hydrocarbon and liquid oxygen as the oxidizing agent. These two components are pumped with high pressure and sprayed in the combustion chamber where they mix and burn.

The other propulsion system I would like to cover in the solid rocket field is the system with the cast in place-case bonded propellant. Here we have primarily two systems.

One is a mixture of a gunpowderlike material known as a double base propellant where sometimes additional crystalline oxidizing agents are added.

The other system uses a rubberlike material as a binder. This latter system was first discovered in the mid-forties by the Jet Propulsion Laboratory and has been extensively reduced to practice going back into Thiokol history in this field starting in about 1948. This system was reduced to practice in "Flyable" solid propellant rocket engines and in 1953 the first demonstration flight was made proving that such a system could fly with good performance. There is basically no limitation on size or thrust that could be provided by this type solid propellant rocket engine.

Now, in considering these two systems, I would like to direct some remarks at some of the basic characteristics that are required of all the rockets, and specifically to see if I can achieve something in the way of putting these two systems in the proper light of utilization, let us say.

First, let's talk about cost, development time, and reliability. These are all very important characteristics.

I mention these together because in many respects they are difficult characteristics to separate. I do not want to go on record as saying that a solid rocket system is more reliable than your turbopump propellant system. Both are reliable if you take enough time and spend enough money.

Time and money lead to things we call reliability growth. Giving proper attention to testing, development, and quality control, I would say theoretically both the solid and liquid systems can be made reliable.

I do believe, however, that history shows that for a given amount of time and a given amount of money that solid system can be made more reliable. In other words, the reliability growth factor is more favor

able to the solid propellant system primarily because of the reduction in the number of components in its basic ultimate simplicity.

Another factor that bears attention in this comparison is the factor that you might call readiness or ease of firing. This particular factor may or may not be of fundamental importance in many areas of space exploration. In other words, you have plenty of time on the launching pad for extensive countdown.

However, this particular procedure is expensive and in addition it becomes rather cumbersome in regard to the upper stages where it is necessary to fire a second or third or fourth stage after the vehicle has left the ground.

So in this respect solid propellant systems are fundamentally easier to stage than liquid propellant systems when you apply them to upper stages.

In addition, you do not have the problem of liquid fuels under zero gravity conditions. Unless special precautions are taken during the staging operations the vehicle will be subjected to certain amounts of zero gravity environment which causes the fuels to become displaced at some unknown place in the tank so it is difficult to start the rocket at this point.

If you use the liquid systems, that is what happens.

In the matter of controllability we have gone through a period of great controversy. Controllability-I am talking about the thrust ability control. I am sure you gentlemen know when a rocket is subjected to side windage or similar disturbing influences, it is necessary to deflect the exhaust jet in one direction or another to keep the rocket on its course. This will provide thrust vector control. Another controllability characteristic important for many space vehicles which require sophisticated guidance is the thrust modulation.

In other words, you would like to have higher or lower thrust in order to control the vehicle much as you have higher or lower thrust on the automobile as you keep your foot on the accelerator. This particular characteristic might be desirable when making a power landing on the moon.

Some years ago solids received consideration for ballistic missile applications; Such applications, as the Redstone and Jupiter, and the Thor and finally the Titan. This was said could not be provided by the solids at that time. I think history has proved that this statement was not true. Thrust vector control can be provided by solids engines and are now doing the job on these missiles; we have the Pershing and the Sergeant in the field of the short-range ballistic missiles. the Polaris in the intermediate range ballistic field, and the Minuteman, which has performed so successfully in the field of the intercontinental ballistic missile.

Certainly the performances of these four solid-powered missiles have proved that the statements that were made historically about what could or could not be done in the way of thrust vector control and thrust termination were basically erroneous. In the matter of thrust modulation, this has not been provided by solid system. I am sure it could be.

I would personally question whether it would be desirable to do this from the standpoint we do have it now in certain liquid engine propulsion systems and if we provide it with a solid we would make the

solid at least as complex and therefore encounter cost, development," reliability schedules similar to that we had with the liquid.

Mr. ANFUSO. Dr. Ritchey, you have spoken about the Minutemanat this point you can tell us the space application of large solid propellants boosters.

Dr. RITCHEY. I would be glad to depart from my outline if you care to. I do have this information in about 2 more minutes. Mr. ANFUSO. Good.

Mr. KING. Could I ask a question right there?

Did you say then that the problem of thrust termination has been essentially solved in the Sergeant, the Pershing, the Polaris, and the Minuteman missiles?

Dr. RITCHEY. Yes indeed. I may add to this. There are certain of the liquid engine-powered ballistic missiles which originally had a small solid vernier motor for projecting the package to the exact proper final velocity whereupon the liquid propellant was terminated. Mr. KING. In the case of the Minuteman, is it possible that the Minuteman might arrive at the target with some excess unconsumed fuel but nevertheless it has cut off its motor at the right place with unused fuel or is it a matter of having the exact amount of fuel necessary to have it reach the target?

Dr. RITCHEY. The truth of the matter is that in all the systems the final engine stage is cut off or thrust terminated when the vehicle reaches the proper velocity to reach the target. This fuel may not be consumed and may stay with the last stage, whether it separates from the package or not or it could go ahead and be consumed in such a manner that it provided no thrust. There are two ways of doing this.

Mr. KING. Then it is not correct to say that the solid fuel has not yet solved the problem of thrust termination; that is an incorrect. statement?

Dr. RITCHEY. This problem has been solved with the solid system. There are two areas in the space application of interest. The matter of what propulsion system does to the sensitive portions of the guidance system and to the manned payload. Here we get into the problem of acceleration and the statement I see has been made many times before the committee that solid rockets had too much acceleration. This is erroneous.

We can provide any amount of acceleration desired by the system or by the payload that can be tolerated. The truth of the matter is that vehicle structure and guidance normally limits the amount of acceleration to a point far below that which can be tolerated by man. This particular characteristic is established by some portion of the system and any desired acceleration can be provided with solids, high or low.

In the way of catastrophic failure, the methods of failure with solids are relatively few when compared to the turbopump liquid. I personally believe that the beginning of catastrophic failure can be detected primarily by pressure rise at which point an abort or escape rocket can be used to separate the manned payload from the propulsion system. This, of course, is a system that was used in the Mercury capsule and will be used in other manned space vehicles where solid escape or an abort rocket is used in case there is failure.