Drummond, Floyd M.

Drummond, Floyd M.

Floyd Drummond recounts his work on the development of NASA's J-2 liquid hydrogen/liquid oxygen rocket engine from its inception in late 1959 through 1967. He describes the early planning, contractor selection, and close collaboration among NASA Marshall, NASA Headquarters, Lewis Research Center, and Rocketdyne, emphasizing how experience from the RL-10 engine informed J-2 development. Drummond discusses the major technical challenges—including turbopumps, injectors, combustion stability, cryogenic propellant handling, and engine qualification—and explains how extensive testing and iterative design ultimately produced a reliable engine for the Apollo program. He also reflects on how evolving lunar mission requirements led to increased performance, longer burn times, and restart capability, while highlighting NASA's systems engineering, procurement, and contractor management practices. Concluding that the J-2 was a highly successful development program, he underscores the importance of building on proven technology, rigorous testing, and cooperation between government and industry.

University of Alabama in Huntsville Archives and Special Collections, Huntsville, Alabama

1971-08-23

This material may be protected under U. S. Copyright Law (Title 17, U.S. Code) which governs the making of photocopies or reproductions of copyrighted materials. You may use the digitized material for private study, scholarship, or research. Though the University of Alabama in Huntsville Archives and Special Collections has physical ownership of the material in its collections, in some cases we may not own the copyright to the material. It is the patron's obligation to determine and satisfy copyright restrictions when publishing or otherwise distributing materials found in our collections.

.MP4

en

Interviews

Audio

ohc_stnv_000013_A

Bilstein, Roger E.

Drummond, Floyd M.

[00:00:07] John Stuart Beltz: Interview with Drummond on J-2 engines. I wonder if we could begin by having you make some comments on your personal experience in the J-2 engine program when you came into it, some of the things you remember most, and maybe we get into more specific questions.

[00:00:31] Floyd Drummond: Well, okay, I'll tell you when we started and how long I was with it. In November of 1959, it became public knowledge that a lot of we civilians here at Huntsville were going to transfer from the Army to NASA. Actually in December of 1959, while we were still on the Army payroll, we started working with NASA people out of Washington. We started on the technical requirements for a liquid hydrogen-liquid oxygen engine. Had a heavy input into the request for proposal that went out in early February of 1960, and had a heavy part in the evaluation of those proposals. The decision as to what contractor got the job was made on May 31st, 1960 by the administrator. We actually started negotiating the contract in June, spent July that way and August. Went under contract to the Rocketdyne Division of North American on September 1st, 1960. Of course, some 4,500 of us had been on the NASA payroll since July 1st, 1960. I was with the J-2 project from December of ‘59 until August of ‘67. It was quite a forward step I think in the state of the art on liquid hydrogen engines. The previous work on this type engine had been done by Lewis Research Center in Cleveland in conjunction with the Pratt & Whitney Company in West Palm Beach, Florida. They had built the RL-10 which is on your list there.

[00:02:38] Roger Bilstein: We talk to Stewart this afternoon I think.

[00:02:40] FD: You talk to Rod Stewart this afternoon?

[00:02:41] RB: We will talk to him.

[00:02:43] FD: That was a much smaller engine around—I think—fifteen, maybe up to 20K thrust, before they were through. The J-2 was started at 200,000 pounds thrust, and it was uprated during the development of it where it could go up to 230, 235 with adjustment of the orifices [they use?] to drive the pumps faster. We took the conventional approach in the development of a rocket engine with a regeneratively cooled bell nozzle, which we had some ten to twelve years experience with alcohol and kerosene engines. We tried to stick to conventional approaches as much as possible. We tried to minimize the development time. We ran into the normal problems you do in any engine development program. You don't know your real problems until you put the thing together. It's an entire engine. You can component test the thing to death. You don't know your problems until you put it all together and try to make it work as a system. The development time took longer than many of us had originally hoped it would. I guess we spent some sixty months before we actually had an engine that we felt was worthy of first flight. Spent longer than that getting it developed to the state where we wanted it.

[00:04:29] RB: What kind of development problems did you run into that lengthened your development time? Can you pick out some specific things and give us some examples of your fix on them, how you solved them finally?

[00:04:45] FD: Well, I think our big problem was in the turbo machinery area. We again took an approach which had some development behind it. We took an actual flow turbopump or pump rather for the hydrogen where all of our experience in the kerosene and liquid oxygen area had been in a centrifugal pump. Hydrogen incidentally being so light. Rocketdyne had been doing some work on what was called the Rover project, a forerunner of the nuclear engine project. They had a ground test pump with the actual flow concept and had been in use in that program. We took many design concepts from that and put it into the J-2 flight pump. The gas generator, which drives the turbines, we had the normal amount of development problems there. Getting the distribution of the propellants and that proper so we didn't have hot spots in the gas generator. We ran into problems there. Had to redesign the combination valving and spray nozzle, sprayed the fuel into the combustion chamber of the gas generator. We had injector problems. We made full use of the knowledge and experience that Lewis and Pratt & Whitney had gained in their injectors. Our only problem was that we had to make that much bigger. We ran into some manufacturing problems there.

[00:06:38] JSB: Did you use the same kind of injector that they [inaudible]?

[00:06:40] FD: Yes, we certainly did.

[00:06:42] RB: Could you describe that a little bit for us here?

[00:06:44] FD: Oh gosh, my boss has a nice picture of the model. A chunk out of the injector.

[00:06:51] JSB: Is this Rigi-Mesh?

[00:06:53] FD: We used the Rigi-Mesh, and a certain percent of the hydrogen was flowed through the Rigi-Mesh to maintain cooling on the injector face. The LOX was flowed through so many posts—it seemed like around 250 posts—came down through there. You'll have to live with my memory problems here a little bit. I've been away from them for four years now. I guess that's about all I can say about the injector. Getting the cooling near the edge of the injector—the outer circumference of the injector—of course was a problem. We went through quite an extensive development program there. We also were concerned about and conducted quite a few tests for stability. When hydrogen gets extra cold, there was a probability of having combustion instability. We ran a program on that and frankly found that that wasn't near as much of a problem in the hydrogen injectors as it had been in the F-1 engine, for instance. They had quite a combustion stability program on that engine.

[00:08:18] JSB: Is that the function of science primarily?

[00:08:21] FD: No, I don't think so. It's more a function of the...Well, in the case of the kerosene engine, of course, it was always a liquid. In the case of the hydrogen engine, by the time the stuff got to the injector—the combustion zone—it was a gas. As we approached the colder temperatures to where we were going to have a phase change from gas to liquid, we were concerned, but this just never happened. We never had a problem there. Our big concern was getting liquid oxygen to the engine and letting it change to a gas there. We were concerned about having gas back up in the inlets to the engine, proper amount of insulation. We had double wall bellows going to both the...These are the double wall bellows going through the hydrogen and the oxygen pumps. By the proper amount of insulation, even external to some of these bellows, and the ducting up into the tanks of the two stages, we did a lot of work with the injection of the S-II battleship stage. This ended up not being a problem. I guess another new concept that we tried on this engine was where we fed the hot gases to drive the turbines in series from hydrogen to oxygen and into this exhaust duct. That was a fairly new thing and that worked out real well. It was a matter of the proper amount of development testing to get the orifices proper so we had the right gas temperature in the hydrogen turbine and still had enough left over to drive the LOX turbine.

[00:10:23] JSB: How do you model that when you want to get the right orifices? Do you put it on a computer? Do you have enough data from other engine programs that you can do that or is it just [inaudible]?

[00:10:32] FD: You [kind of?], well, in this particular case, we had some data from the RL-10. Of course, it's not a simple matter to scale up from a 15,000 pound engine to a 200,000 pound engine. You take that to start, and you run some very short duration development tests to get some additional data. You keep running this through the computer as you gather additional data. This is a big help, of course, in the final analysis. You're working your way up by steps to a combustion system. The back pressure from the size of your orifices in this exhaust duct, that you try by computer, and you get the final answer when you put the thing together. I can't recall how many hundred development tests we did over the years. Have you talked to anybody in the engine program office on J-2?

[00:11:34] JSB: Not here. No, we have been out to Rocketdyne and talked to Paul Fuller.

[00:11:40] FD: Are you going to talk to anybody in the engine office here?

[00:11:43] JSB: Yeah, we talked to Belew and Brown especially.

[00:11:48] RB: We have interviews scheduled with Thomson sometime.

[00:11:50] FD: Jerry?

[00:11:51] RB: Yeah, and with Bob Pease. We talked to Dick Rogers already.

[00:11:53] FD: Okay. And you're going to talk to Bob Pease?

[00:11:55] RB: Yeah.

[00:11:56] FD: Okay. He can probably tell you a lot more than I can because he's still with the engines. He lived with the J-2 on site of Rocketdyne up until a little over a year ago, I guess, when he moved back here.

[00:12:11] RB: One thing that still is unclear to me is how the engine really evolved in terms of the relationships between Marshall and say Rocketdyne. Did you more or less design the engine in Marshall and then say to Rocketdyne, “Here it is,” or did they design and say, “Here's the engine, now what do you think of it?”

[00:12:32] FD: No, we came up with the requirements of what we wanted the engine to provide.

[00:12:39] JSB: Just like you're doing on the shuttle, including specific impulse and thrust? Was that specific?

[00:12:45] FD: Yes, it was that specific. It was quite thorough document. It was more than RFP, I think.

[00:12:52] JSB: Flow rates and all that?

[00:12:54] FD: No, I don't think we went to…I don't think we could be that specific. We specified the thrust we wanted and a range of ISP that we desired, which we thought was attainable from what data was available on the hydrogen-oxygen combination. We did specify that we wanted a conventional bell chamber. Anything else would have been too big a step, we thought at one time.

[00:13:27] JSB: Were anybody during this time trying to sell ideas like aerospike or things like that maybe? More Aerojet concept [in mind?]?

[00:13:31] FD: No, no. Well, things were a little [austere?] in 1959 and ‘60.

[00:13:46] JSB: I have one question along with that. As you know, the Silverstein committee suggested the use of LOX-hydrogen for the upper stages, and that was December 15th, ‘59.
It seems that you were engaged in this in November of ‘59...

[00:14:00] FD: No, no, you misunderstood me. In November of ‘59, it became public knowledge that a bunch of us Army civilians were going to work for NASA. In December of ‘59, in fact, on December the 28th—which happened to be my birthday—was the day we started working on this thing here in Huntsville. That's the reason I remember the specific date.

[00:14:21] JSB: Okay, so what I was trying to isolate is obviously the Silverstein committee had to have inputs to decide to go to LOX-hydrogen. Maybe these came from Lewis from his long period as director of Lewis?

[00:14:37] FD: I'm sure it did.

[00:14:39] JSB: And not from a Marshall [sponsor?] then because Marshall or ABMA had never been into hydrogen before.

[00:14:46] FD: The requirements for the engine came from a lot of studies. I'm sure that was one of them. We were specific enough in our RFP, we specified that this engine should be capable of being used by itself—a single engine—or in clusters. We didn't say how many. The requirement was there for a larger payload capability if we were going to do any more in space.
I can't say that the requirement to go to the moon was there at that time because it wasn't. You always have to start your engine development program earlier than your vehicle development program because it takes longer time. You need an engine before you can do any kind of qualification flights on a vehicle. So we were specifying…We allowed, let's say, the contractors to propose a 165K engine or a 200K engine. The reason we did that is because we had 165K engines at the time. We had the H-1, which was already 165. The three major contractors that proposed—Aerojet, Pratt & Whitney, and Rocketdyne—all proposed at the 200K level. They were allowed the option to go in steps, you know, do a pre-flight rating program on 165, a qualification program on 200. They all chose to go to the 200 originally, which—well, Monday morning quarterbacking—is the way to go. If you want a 200 K engine, you start out building one. That wasn't too big a step from 165 to 200.

[00:16:38] JSB: But isn't this engine itself capable of just by changing fuel mixture about a 239, 237?

[00:16:47] FD: Well, I've been away four years. When I left, I think 235. We could orifice, get the right mixture ratio, and get up to 235. That came later. [That was not?] a requirement originally.

[00:17:00] JSB: Is this an expensive program to uprate the engine?

[00:17:06] FD: No. Once you get your basic engine developed to uprate it isn't real expensive. We have a lot of good history to support that on the H-1. It's been uprated four or five times, I guess. I don't even know what it is. I think it was 205K last I heard. Now that's a relatively inexpensive thing to do. You don't make a big jump, you know, from 150 to 200 in one step.
You take it in increments. Kind of by fine-tuning your pump system usually and your injectors, what gets you there. But the uprating from 200 to 235 wasn't expensive in the J-2.

[00:17:57] JSB: Nevertheless this is a change in the contract when you uprate. Does the contractor stand to make money that he perhaps lost on the original development program by uprating? Is there a chance to catch up a little bit on that?

[00:18:15] FD: I'll have to say this. Anytime you put in a change to a contract, you have to say, well, there's an opportunity for the contractor to recoup a little bit [if he’s lost?]. The only way I know out of that is to go to a fixed price contract and don't change the requirements. I don't know of any program in the history of NASA that's done that.

[00:18:44] RB: I was going to ask you about the other bidders. There were only…I thought there were four bidders on it.

[00:18:51] FD: There were five.

[00:18:53] RB: Remember who they were?

[00:18:55] FD: The other two was…Now wait a minute, I better…GE bid. GE submitted a bid. Reaction Motors did not bid. They came to the bidder's conference. Bell, I believe, submitted a bid. I won't be 100 percent sure about that. I know GE submitted a bid.

[00:19:17] RB: Aerojet, Pratt & Whitney, Rocketdyne, GE, and Bell.

[00:19:23] JSB: How was this source selection made? Do you have any insight into that?
The announcement was by the NASA administrator.

[00:19:29] FD: Yes, the source selection, we had a technical evaluation team and a business evaluation team. These fellows lived in Washington for about six weeks, I guess.

[00:19:42] JSB: TDY from here?

[00:19:43] FD: Some were from here, some were from Lewis. Mr. Pease was on one of those teams. Jerry Thomson was on one of those teams. I personally was not on the team. I stayed home here in Huntsville and fed some information to Jerry and Bob Pease. Then the source, or rather the technical evaluation team, made presentations to the source evaluation board. Mr. Herman Widener, our director of S&E, I believe was the chairman of the SEB. The SEB in turn made presentations to the administrator. There was a fellow who went back to Case Institute.

[00:20:26] JSB: Glennon.

[00:20:27] FD: Glennon, Dr. Glennon. He made the announcement the last day of May in 1960.

[00:20:35] JSB: Do you have any idea where that selection was made? Is it just made out of the findings of the committee? Glennon announces it, but it's really basically a Marshall decision?

[00:20:47] FD: Oh no, I wouldn't say this is basically a Marshall decision at all.

[00:20:51] JSB: You say it was more an overall NASA decision?

[00:20:55] FD: Oh yeah. This thing was really conducted out of NASA headquarters. A gentleman by the name of Del Tischler was kind of, I don't recall his exact title, but he was kind of chief of the propulsion group at NASA headquarters. We supplied him people from here. Lewis had people on the evaluation teams. He was kind of, I guess, chief coordinator of the evaluation. I'm quite sure he was on the source evaluation board. This was handled the way we're still handling them today. You have evaluation teams, and they in turn report to a source selection board or source evaluation board. They in turn make presentations on a big procurement that usually ends up [going to?] the administrator. The administrator makes the selection. I know that's the way it was done on the J-2.

[00:22:13] RB: Do you remember the kinds of technology that were transferred from Lewis engine experience, say, to the RL-10 that went to the J-2? Could you make some comments about the interplay and the interflow of information that leads from one engine program into the next one?

[00:22:35] FD: Yes, I can comment on that fairly detailed, I think. I personally went with Jerry Thomson and a couple of injector experts from Rocketdyne to Lewis. We spent a couple of days up there going over data they had collected, drawings that they had on this type injector. We went through manufacturing processes on the injector. Lewis had a little manufacturing shop up there where they had made some prototype engines. We went through the manufacturing process on the regeneratively cooled tube thrust chamber. We did the same type thing on their turbo machinery, particularly on the RL-10. Mr. Tischler's—well, let’s say—it was policy at that time, we had a program review about each three months at Rocketdyne usually. We had a team that went for the first couple of years anyway. We had Lewis people on our J-2 team.

[00:24:03] RB: Excuse me, let me ask you something. You went to Lewis went to look at the injector stuff and the turbo machinery. Was this basically RL-10 material?

[00:24:13] FD: And thrust chamber. Yes, RL-10 covers a lot of sins. I guess that covers from the time that Lewis started in the hydrogen engine field. I believe that was around 1956 they first started playing with this—’56 or ‘58. Rod Stewart can fill you in on that. I guess to put it bluntly, we took Rocketdyne and went to Lewis to pick Lewis' brains to get all knowledge that they had into Rocketdyne's hands to see if they could make use of it. They did make use of it wherever possible—the Rigi-Mesh injector, for instance. The regeneratively cooled tubes—Rocketdyne had to go to a different manufacturing process mainly because of the physical size of these tubes.

[00:25:13] JSB: Lewis wasn't annealing them and doing them out of that…What kind of nickel alloy [inaudible]?

[00:25:21] FD: We used that metal also, but the actual process of forming the tubes and putting them together had to be changed because the RL-10 is a little big rascal. I forget the height of this offhand, but that's a pretty tall tube.

[00:25:35] RB: Eleven or twelve feet I think.

[00:25:38] JSB: Well, Rocketdyne just bought those tubes from a manufacturer. They would just get them in a big thing, and then they’d buy them bent.

[00:25:44] FD: They were forming their own tubes years ago, and they are buying them today I think. They were formed [inaudible]. Putting them together and furnace brazing [techniques?] them were a little different. They used the same basic metals.

[00:25:58] RB: About what time were you up at Lewis then with the J-2 people going through Lewis' files?

[00:26:03] FD: My first trip was September 1960, right after the contract was initiated. We worked closely with the Lewis people, real close for at least three years. During that time they took on an engine development program of their own. However, we kept in touch with them and kept them…Let's say we kept utilizing their knowledge any time a problem came up.

[00:26:34] RB: Okay, let me make a statement here. You tell me if it's right or wrong. I was wondering where Pratt & Whitney's experience filtered into the J-2 program. The point of filtering would seem to me was Lewis because Pratt & Whitney would have their reports of Lewis and you had access to all Lewis' stuff, so that's how the transfers made.

[00:26:55] FD: Well, if there was any direct contact between Rocketdyne and Pratt & Whitney, I wasn't personally aware of it. We took the data that was available to the government at Lewis and made it available to Rocketdyne. There was no infringement of proprietary rights, of course.

[00:27:15] JSB: Going back a little earlier, there was some work in hydrogen technology at Caltech and Aerojet. Did any of that technology get into the loop?

[00:27:30] FD: I guess I can't answer that. I wasn't personally aware of it. Who had the contracts with…?

[00:27:36] JSB: These were just individual laboratory operations.

[00:27:40] FD: Was the government involved?

[00:27:42] JSB: I think the Navy sponsored a little bit of the research.

[00:27:45] FD: Maybe. I wasn’t aware of that.

[00:27:48] RB: Okay, can you go on from there a little bit and tell us a little bit more about the development of the J-2 after you got the materials from Lewis?

[00:28:03] FD: Well, Rocketdyne just started by doing an injector test with an old, heavy, short thrust chamber, which is again normal. They started doing turbopump development tests. We were going to get this job done in forty-five months originally. As I said before, it took about sixty months. We got into our PFRT program—pre-flight rating test program—a little behind schedule.
We came through it in pretty fair shape. Went into a qualification program. When I left, we were under contract to deliver or to buy from Rocketdyne about 155 engines. I don't know where we are today—if we bought that many or if we're under contract to buy more.

[00:29:04] FD: We had to satisfy two different situations. We had to satisfy the S-IVB application, single engine. We had to satisfy the S-II, which was a five-engine cluster. During the development of the vehicle along with the engine, after President Kennedy and Congress decided we were going to go to the moon, requirements on the J-2 increased. We started out with the requirement that it only had to run for 250 seconds. That had to be changed to 500 seconds, and we qualified for 500 seconds. It had to have a restart capability. That was not an original requirement. Once you started, let it run and quit.

[00:29:54] JSB: I asked you a question along here. Did you have to establish separate production facilities out at Rocketdyne for the engines going on the cluster and those that were going on the…?

[00:30:05] FD: No, we did not. That was a requirement from the start.

[00:30:08] JSB: They were to be the same?

[00:30:10] FD: They were to be the same.

[00:30:12] JSB: In other words, with some slight modification, you could use the S-II engines on the S-IVB?

[00:30:17] FD: Oh, yes. Actually, as far as the acceptance testing of the engine went, we could take one and send it anywhere. As I recall, it was simple to put in the restart capability. It was just simple to have it in all the engines, all of the S-IVBs that were going to use it. Before we delivered the engine, we had to know where it was. I can't remember what the engine was.
It seems to me like it was in the LOX line to the gas generator. We had to do something. Mr. Pease can tell you that. There was a…

[tape cuts out]

[00:31:13] RB: I think you were going to say something about the LOX line in the gas generator?

[00:31:17] FD: It seems to me like it was the LOX line to the gas generator, but I won't say for sure. Ask Bob Pease that question. There was a slight difference in the kits that had to go to the S-II engines rather than the S-IVB. As far as acceptance testing the engine, we acceptance tested them, and we didn't care where they were going. They all got the same.

[00:31:39] JSB: Was there anything additional that had to be done in the program to manned-rate the engine or was it just the normal testing and quality program?

[00:31:47] FD: Qualification program manned-rate the engine. Manned rating was kind of a new word for us. It came up. I wouldn't say it added much to the qualification program, but qualification and manned rating became synonymous after a while. As far as qualifying an engine, we had that in the program from the start. We had experience in doing this in the past.
We had a pre-flight, what we called a PFRT engine, pre-flight rating, and then a qualification engine. The manned flight aspect came in, and that qualification kind of became synonymous after a while. Offhand, that's about all I can remember. You have some questions that might generate some other thoughts, but...

[00:32:48] RB: What about the gimbaling system? Rocketdyne at one time was experiencing what's kind of a screw system. Do you remember that? Was that ever adopted?

[00:32:56] FD: They proposed a screw jack, yes.

[00:32:59] RB: But it was never adopted really. Another question too about the turbine machinery. The bearings were cooled by the propellants going in. Was that new with the J-2 or had that been done on other engines, do you recall that?

[00:33:25] FD: It had been done on other engines.

[00:33:28] RB: So that wasn't necessarily a big breakthrough by Rocketdyne?

[00:33:32] FD: Oh, not a big breakthrough. We had used lubricant in the H-1 engines and the Jupiter engines. It had always been a problem because of the cold temperatures surrounding the [inaudible]. Rocketdyne, I believe, had used this on their rover—the actual float pump—was experience they had. There were problems associated with it, I don't want to tell you it was simple, but I don't think that was one of our major problems at all.

[00:34:05] RB: Since Rocketdyne already had a big Santa Susana field laboratory testing engines there, why was it deemed necessary to build test stands for the J-2 out here, which occurred kind of late in the program, didn't it? ‘65 or something? What was the reason, your argument, for having a kind of engine?

[00:34:29] FD: What we built here wasn't a J-2 engine test stand. It was an S-IVB battleship type test stand.

[00:34:38] RB: Oh, okay. So it was an entirely different thing. What kind of problems did you run into when you got to the point of finally mating the engines to the stage?

[00:34:50] FD: We got into all kinds of problems. Our first experience was at Sacramento with the S-IVB stage: liquid temperatures, LOX and hydrogen going in the pump. Gimbaling, it's always a problem after you get the stage. We ran into these kinds of problems. You develop the engine on a hard test stand, then you put it on a battleship stage test stand, which again is rather inflexible, then you finally put it on a flight stage. Going through this sequence is worthwhile. You get rid of your major problems. When you finally get to the flight stage, about all that's left—the problems that show up that you've tried to compensate for and prepare for—is the structural interface between the engine and the lightweight flight stage.

[00:35:54] FD: The other problems are with getting your propellant out of the tanks and into the engine. This normally has been worked out on the battleship stage. Insulation on the flight stage—you try and use the same on your battleship stage, but the wall thicknesses usually are greater. In the case of cryogenic engines—especially J-2—where both fuel and oxygen are liquid, you have to keep your stage walls thin and your insulation as thin as possible because of the weight involved. That's a problem that usually gets worked out are the fine details of it once you get in the flight stage.

[00:36:42] FD: The structural interface when you gimbal this thing over a [full seven degree square?], you sometimes find some problems there. We found one of our early engines went to Sacramento, and we found a gas generator problem. We just happened to find it there. It showed up. We found a hot spot in the gas generator. We redesigned the orificing a little bit, spraying the propellants into the gas generator. The S-IVB, or rather the S-II, where you get the cluster, your biggest problem there, in my estimation, is a thermal problem. You've got a single engine all by itself. You get more natural cooling to it, I guess is the way I can say it. When you've got five in a cluster, you've got the heat from one engine being transmitted to heat the other. Your thermal balance between the five engines is a problem that, again, you attempt to work out on the computer long before you get there. You usually find some fine tuning that has to be done after you put it in a cluster. In the case of the S-II, I believe I mentioned before, our thermal people were quite concerned on assuring that you had liquid at the pump inlets.

[00:38:15] JSB: What was the commonality between the F-1 and the J-2? Was Rocketdyne able to use the experience developed on the F-1 at all on the J-2 since the F-1 program was a little bit older? Or the H-1 program, [since they did that one?].

[00:38:32] FD: They certainly used their H-1 and Jupiter and Thor engine experience. They had, I guess, as much knowledge and experience, or probably more so than any other engine development in the country. Their F-1 experience was helpful on the liquid oxygen side of this thing in the turbo machinery area. They had their experience in hydrogen. It was kind of limited to this rover pump, which was a ground test pump for a nuclear project. Because they had not had hydrogen, the F-1 pump and kerosene, they did not have a lot of hydrogen experience that could be readily utilized in the injector area or the cooling area, for instance. Other than the general type experience you pick up in doing a LOX-kerosene engine. There was nothing specific from the F-1, I don't think. The F-1 and H-1 development program gave Rocketdyne and us, I think, the areas that we should be concerned about and look into real deep. Combustion instability being one of them. I guess it always will be a problem with liquid rocket engines. Fortunately, in the hydrogen engine, it's not as big a problem as the kerosene.

[00:40:16] JSB: Could you say a few words about the M-1 development program?

[00:40:21] FD: Very few. [laughs] We had a part in its starting here in Huntsville. It became a requirement for a vehicle called the Nova, which had never evolved into anything concrete. We had management of that here for a rather short time. It was transferred to Lewis.

[00:40:50] JSB: Was that at the same time that the Centaur was transferred up there? It was kind of going through reorganizations. Centaur program, the M-1 was transferred up there.

[00:40:58] FD: No, I think the M-1 was transferred earlier than that. I'm pretty sure it was. Rod Stewart can help me on that. He had the M-1 engine here for them at the time we had it, I believe. It was around one million pounds, up to a million and a half hydrogen. [Our jet?] to my knowledge, never got to an engine systems test there. They did some component testing, injector, turbopumps. The requirement kind of went away for the engine. That's about all I know about it. I had personally nothing to do with the M-1. I know Rod did.

[00:41:51] RB: When you began work on the J-2 design, were there things that you wanted to do that were impossible at the time because of the limits of the state of the art of metallurgy? Were there things that you decided you had to do and kind of had to push the state of the art of metallurgy to a point where you could really accomplish it?

[00:42:15] FD: No. One of our guidelines or ground rules in our requirements spec was to stay away from the requirement for exotic metals. I recall that specifically. I don't recall having to develop any new state of the art business from a metallurgical standpoint.

[00:42:41] RB: Well, just about to run our time out. One of the things we would like to get from people, if you remember them well or tell me about, any funny stories?

[00:42:49] FD: Any funny stories? [laughs]

[00:42:53] RB: Sometimes we get comments from people, “Gee, NASA engineers just out there working with their nuts and bolts, don't they ever have any fun? Doesn't anything humorous ever happen?”

[00:43:04] FD: We had a lot of fun in the J-2, I think. We had a lot of headaches, a lot of head-knocking sessions internally and with Rocketdyne, but we managed to have some fun on it too. Being a little prejudiced, I guess, I think the J-2 engine program was a damn good development program.

[00:43:23] RB: I think Rocketdyne quoted you to that effect in one of their sequences. I remember reading it somewhere. Maybe they didn't quote you exactly “Damn good.” I remember that after the qualification test, you did make that comment. It was a very good development. Excuse me, I interrupted you here. Go ahead.

[00:43:43] FD: Well, I don't have any specific funny stories connected with the J-2 itself, but on a trip to Rocketdyne, Dr. von Braun—he made about two a year where he would tour most of our prime contractors—of course, he was always interested in what's new, you know, what are you doing that's really new. They came out the first time, they showed him some of their toroidal engine work, which is another name for aerospike. They had this semi-circular thing cut in half, and they kind of ended up saying you can buy propulsion by the yard. He turned to Willie Mrazek—Dr. Mrazek—and he said, “I want you remember that Willie. Now we're going to order it by the yard instead of by the pound.” He was quite enthused about that program. I guess it's kind of fallen by the wayside now—the toroidal engine in favor of the high pressure belt. But yeah, there's always time for some funny stories along those sixty hour weeks and head-knocking sessions. I imagine that we're in for some more of this shuttle engine that's just going under contractors.

[00:44:59] JSB: Has this recent…You want to turn that off, Roger?

[00:45:03] RB: Okay.

[tape ends]

0:45:36