Thomson, Jerry

Thomson, Jerry

J-2 Injector

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

1971-08-23

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Interviews

Audio

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Bilstein, Rodger E.

Thomson, Jerry

[00:00:07] Roger Bilstein: I wonder if you could, from your recollection, make some comments about where the porous injector face got started and how it got into Pratt & Whitney and how the transfer occurred from the RL-10 to J-2 and stuff like that.

[00:00:21] Jerry Thomson: Oh, good. I might be able to make a few [thousand?] comments about that because I was involved in this area quite a bit back in the early days. The J-2 procurement—I'm sure you've already determined—took place in about 1960. That procurement—the specifications and so forth—were all prepared here in the lab at that time. When we prepared the procurement on the J-2, we visualized it as being somewhat advanced engine relative to the RL-10 because we had already been working with the RL-10. So when we made the solicitation—why, I can't remember now whether it was four or five contractors bid on that J-2 engine—but the winning contractor, who was Rocketdyne, did not offer an injector type like what we ended up with. As a matter of fact, they offered a self-impinging injector or it might have been an unlike pattern—you know?—where fuel was impinging on a LOX stream—I can’t remember exactly—but the man at Rocketdyne that was in charge of that effort then was a very good friend of mine that I’ve known since about 1952 was Bill Mower. Bill Mower…

[00:02:23] RB: How do you spell that last name?

[00:02:24] JT: W.W. Mower: M-O-W-E-R, and he is still there with the company. After Rocketdyne won the procurement, won the contract, then we began to interface with them to discuss in more detail what we liked and didn't like about their design. My discussions with Bill Mower there at Rocketdyne, we decided that we would go and investigate at Lewis Research Center work which had been done up there by Bill [Tomaszek?]. Bill [Tomaszek?] in the rocket propulsion division up there had for a number of years been experimenting with a coaxial injector pattern about fifteen thousand thrust size. He had investigated this particular injector configuration even prior to the design of the RL-10 engine.

[00:03:44] JT: It was dated back a good ways, as I recall. But their design at Lewis was a flat-face injector with coaxial elements, then the LOX through the center with a fuel curtain around it. During the course of that experimental work up there the first basic information was derived that led then to the RL-10 engine design injector. And, you know, when the Pratt & Whitney people saw that data, they took it a few steps further, and they put a convex shape to the injector face and focused it so that the focal point of all of these elements then was right at the throat of the motor. They did that for reasons like that if you have a flat face, the LOX springs when they hit the converging section of the nozzle cause overheating problems in there, so by focusing it so that everything was aimed right at the throat they took a little bit of the load off the converging section of the motor.

[00:05:20] RB: I'm glad you explained that because I noticed that on the injector, and I didn't
know really what the reason was. Why didn't they use a similar thing then for the H-1 and F-1 injector cases?

[00:05:30] JT: Well the H-1 injector preceded the work at Lewis, and the F-1 was based on the H-1. It wasn't really anything back in those days that we could use like experience on it, the RL-10 and so forth. But anyway, by converging those elements at the throat, they took some of the problem off of the—and these are improvements that Pratt & Whitney made to the concept—but the Pratt & Whitney injectors or their thrust chambers start tapering as soon as you leave the face. There's no straight section and then a converging section. They start tapering immediately. So they made some [very?] good improvements over the original work that we done at Lewis Research Center. This was a great deal of interest to us when we started the J-2 program because we said, “Well, gee, that thing has turned out so well.” I kind of pressed Rockedyne into taking a look at it.

[00:06:42] JT: So then Bill Mower and I and another guy who worked out there named John Campbell who worked for Bill Mower, all three of us went up to Lewis Research Center to visit Bill [Tomaszek?]. That was about 1960 we went up there. We sat down and reviewed what the Lewis work had been and made some estimates of how this then could be translated into a J-2 injector. But initially the J-2 program started off with an unlike triplet injector or a doublet—I can't remember—but it was flat-faced and no rigid mesh. We entered the test program with that kind of a configuration. Bill Mower was a very practical sort of fellow. He said, “Jerry, we hadn't got people at Rocketdyne that we think can consistently build that high quality piece of equipment”—which is a rigid mesh concentric orifice injector. He says, “We don't think we can build that high quality equipment,” and so he says, “It would be a shame to go into that at Rocketdyne and spend a lot of money and then have two-thirds of them rejected during the course of the manufacturing.” So he still favored the flat-face, no-face cooling, multi-element pattern. Again, I can't remember whether it was like-on-like or whether it was unlike-doublets or something triplets or what, but I believe it was one stream of LOX with two fuel streams impinging on it. I think that was Rocketdyne's initial approach. But when we entered the test program at Rocketdyne, which I don't know, came about 1962 or something along like that, we had a lot of problems. We had face heating problems.

[00:08:57] RB: Mower was right then.

[00:08:59.] JT: What?

[00:09:00] RB: Mower was right. They had a lot of problems, didn't they?

[00:09:02] JT: Well, they had problems, but they were design problems or they were development problems. He was forecasting problems in fabrication of a high-quality injector like a coaxial.

[00:09:18] RB: Oh, I see.

[00:09:20] JT: But when they had these problems, they were both face heating problems, and some of these streams were getting out through the wall, causing wall overheating problems.
We had some instability problems with that injector configuration that they initially chose. It was good that there had been a little bit of work started at Rocketdyne on this coaxial approach, that is, the rigid mesh faced coaxial approach. They had sort of taken that along as a backup, hoping that the solid-face injector would have been good enough. Since it didn't turn out that way in the course of the development testing, then they were forced to go back and take a look at the coaxial rigid mesh face, and we gave them a lot of money to give that a real…a lot more emphasis. As a result, then Rocketdyne began to have more success in the course of their injector development. It still had a lot of problems, you know, there were distortion problems—the rigid mesh face would expand and contract, and this caused a little problem as far as the LOX [posts?] are concerned. We'd get straight LOX springs into the wall. But Rocketdyne kept making improvements, and finally, did come out with a real high-class injector.

[00:11:07] RB: Was Marshall at this time doing parallel injector studies here in Huntsville? Or was most of the actual hardware dirty hand work going on out at Canoga Park?

[00:11:17] JT: It was going on at Canoga Park. We had a little bit of model injector element testing going on here in the center, but it was not on any kind of a scale to give valuable inputs into that Rocketdyne design. That Rocketdyne design was really a result of, first of all, having this Lewis research knowledge. We did make all that available to him. Then we turned over to Rocketdyne all this knowledge that had come out of the RL-10 program. Then Rocketdyne just simply took a couple of approaches and made it even better.

[00:12:03] RB: Well, given Pratt & Whitney's experience with Centaurs, with liquid hydrogen technology, and given this injector face work they’d already done, why didn’t they get what became the J-2 engine? Why didn’t they get it, and why did Rocketdyne get it?

[00:12:19] JT: Why didn’t Pratt & Whitney get the job? Because that isn’t the only criteria for contractor selection, you know? Injector design is just one of hundreds. The reasons Pratt & Whitney didn’t get the job are all in the evaluation files.

[00:12:49] RB: Rocketdyne seems to be pretty successful at getting engine contracts.

[00:12:52] JT: Yep. I think in the case of J-2, the biggest thing that drove Rocketdyne in was the fact that they offered a program for about thirty-eight million bucks. Their competition was quite a bit in excess of that.

[00:13:10] RB: Did Rocketdyne's association earlier through the H-1 program, did that make it a little bit easier for them, you think, that they knew the people and knew Marshall's philosophy?

[00:13:23] JT: No, I think that wasn't very significant there because the evaluation was a NASA thing. It wasn't limited to Marshall. The evaluation was done in Washington. The guy who headed that was Del Tischler.

[00:13:42] RB: We tried to get to talk to him, but we couldn't. We talked to John [inaudible].

[00:13:45] JT: Yeah, Del ran the evaluation. I can't think of who the second man was on that. But there were a few of us at Marshall up before that. Of course, a great number from Lewis Research Center and various places. I think even the Air Force people were involved.

[14:08] RB: Could you tell me a little bit more about this rigid mesh material? Its origins, where it came from?

[00:14:15] JT: Porous Media is one of the companies that…

[00:14:24] RB: Aircraft Porous Media Incorporated is the name I've got here.

[00:14:27] JT: Yeah. I don't know how they ever came about that darn stuff, whether it was used as a filtering material in some of their other projects—you know?—and they just simply found out that, hey, maybe injectors, or maybe thrust chamber people would be interested in this product or just how it came about. The company did go through a number of development processes and finally coming to a real high quality product. I don't know whether it was just largely their own doings or whether the government sponsored them in this activity under some research contract or whether some other agency was interested in it or just how it came about. But by the time it got utilized in the RL-10, why, it was a pretty good high quality product. There may have been some further improvements in its application to the J-2. But if there were, they were minor because it had already reached the plateau as far as maturity is concerned.

[00:16:04] RB: I'm realizing there are lots of parts and subsystems of J-2. I wonder if you could say that rigid mesh was really a significant part of the J-2 success or it didn't have anything to do with it. Just how important was the rigid mesh to the injector face, injector material?

[00:16:26] JT: I'd say it was rather important, but it wasn't essential. The job could have been done without that rigid mesh material. You could have gone to a whole lot of drilled holes in the face for it, let the gaseous hydrogen come through it. There's a lot of other principles that could have been employed, but this stuff not only gave you a lot of small weep holes for the fluids to pass through but it provided a pretty good structure. All those tubes that came down to bring the LOX from the top of the injector dome, they were all fastened to the rigid mesh material.

[third person talking Jerry Thomson, inaudible]

[00:17:40] RB: There was something else that Dave was talking about. He said that he remembered or heard some story about the fact that when Von Braun was out at North American and was watching some of the experiments with J-2 injectors before they were using rigid mesh, and he was also talking about the RL-10, urging them to go into the rigid mesh that had been used by Pratt & Whitney. Do you remember or hear that or do you remember anything about it?

[00:18:06] JT: No, I don't. That most likely did happen or something. I'm sure that those of us that were, you know, more intimately involved with that thing were considering the application of rigid mesh to the J-2 all along [laughs].

[00:18:32] RB: That’s what struck me as you were talking, it had to happen long before that. I know you've got to go to this meeting, but there's one other question here, and maybe you can't answer it. But early at one point where they're still talking about a propulsion system for the S-IV stage, they were considering using the LR-119 engines—Pratt & Whitney—and they ran into some kind of trouble, and so they decided to go to the LR-150. This was back in 1961. Do you recall what the difficulty was, and why they went from the LR-115 to the 119?

[00:19:17] JT: It escapes me for a minute.

[00:19:19] RB: They finally wound up with the RL-10. But I just came across this reference that they had some trouble, and I haven't found out yet what they were.

[00:19:28] JT: Well, we had trouble with the development of the RL-10. We had very serious development problems in terms of starting the engine and one problem in terms of igniting the engine. We blew the test stand down a couple of times down in Florida. It was a horizontal light versus a vertical light. You light it horizontal, the oxygen accumulated in the motor and provided a nice, smooth ignition when you brought in hydrogen. When you turn the engine this way, why, all the way in the LOX ripped out. Therefore, when we started, we got no ignition until the diffuser filled with hydrogen, and then she lit.

[00:20:20] RB: [laughs] And then she really lit?

[00:20:21] JT: Yeah, then she went. Twice! Well, I don't know about that 119 thing, because it don't ring a bell.

[00:20:35] RB:I’ll have to go back and find some documentation. We talked to Rod Stewart, and he's forgotten almost all about that. It's been so long ago now, twelve years practically.

[00:20:42] Yeah. Well, I remember a little bit about the J-2 injector thing because injectors are what I trained in back when I was in the industry.

[00:20:58] RB: Do you have any more comments to make about the J-2 injector development, and some of the problems that Rocketdyne had, and the Marshall inputs to that program?

[00:21:12] JT: Nope…make some comments about the F-1 if you ever get interested in that.

[00:21:18] RB: Ok, you got time? You want to do it?

[00:21:21] JT: Well, if you ever really want to hear a good story, back about 1963 or 4 [sic], we ran into this F-1 combustion instability problem. We had such a terrible thing there on our hands until there was sort of a national ad hoc committee created to do nothing except to concentrate on the solution.

[00:21:57] RB: How do you mean a national ad hoc? [Inaudible] people from Lewis and other NASA…?

[00:22:02] JT: Yeah, and universities. I hated the thing, and it brought in people from all over the whole country consult and assist us in the solution to that problem. It took us about a year and a half, spent thirty something million bucks solving that problem.

[00:22:22] RB: How would you summarize then the problem as it originated and how you worked it out? How would you…

[00:22:32] JT: Well, we were going along fine in the F-1 engine testing, we all of a sudden began to destroy engines. We destroyed seven—or at least we blew up seven times—due to combustion instability. It was obvious that the injector system that we were using was not going to do the job. It was a flat face, unlike, doublet with a LOX ring and a fuel ring—copper ring—it was…After about a year and a half or two years of real intensive investigations and trying every kind of a concept you can think of, we finally converged on a solution that was basically the adaptation of baffles to the injector face.

[00:23:35] JT: Still that wasn't good enough because the additional baffles caused performance degradation, caused baffle heating problems, local accumulations of fuel and even them themselves caused perturbations and instability. So it was just a laborious step-by-step fix this and fix that and fix something else and go back and refix what you had fixed using a lot of theoretical ideas and a lot of barnyard philosophy and whatever else we could.

[00:24:19] JT: We finally got an injector system that was not only did it exceed the requirements that we had started the program with but it set the pace for all the future programs. All the future injector programs both the Air Force and NASA require a dynamically stable system—you know?—where you can bomb artificially and what you see how long it takes for the disturbance to quiet down. The Titan program adopted the procedures and the techniques that we worked out in F-1.

[00:25:01] RB: Well, did this bombing begin though with the H-1? There was some instability with the H-1. Did it begin there or did it begin with the F-1?

[00:25:10] JT: The experimental bombing and watching the recovery times did start in the H-1.

[00:25:22] RB: Did the techniques differ very much from the H-1 to the F-1?

[00:25:26] JT: Yeah, they advanced quite a bit from the H-1 to the F-1.

[00:25:32] RB: And what were the differences then?

[00:25:33] JT: Well, in the H-1 we did use black powder charges as the source of energy, but we didn't understand just what was going on in there when these charges would go off. During the course of the F-1, why, we built these two [inaudible] motors where you could photography see exactly what happened when we set a bomb off near the injector face. We soon learned that the bomb was like a detonator. It was just a…then the real energy came from the reaction of the kerosene that was accumulations in the injector face during the preparation process.

[00:26:30] JT: Whereas the H-1 used seventy or hundred grain bombs, black powder bombs. The F-1 we only needed about a nine grain bomb. The location of the bomb we determined during the course of the F-1 was real important. In the H-1 program we set off the bomb at the center of the injector, it would cause the wave that went to the wall and then came back. We found in the course of the F-1 testing that that was the most favorable place to put the bomb. If you really want to create a disturbance that's difficult to damp, you need to put the bomb near the [engine?] wall. I think that all of our today's criteria and procedures for bomb testing engines really go back to what came out of that F-1 program. It's true that the H-1 had done some, but it wasn't near as significant.

[00:27:41] RB: When you finally began to solve the F-1 problem, was it, I think you said, just a convergence of ideas and people? Was there anyone, though, that maybe took the lead, the university or Marshall or Rocketdyne? Was there somebody or someone, you yourself?

[00:27:57] JT: I tell you there was about four or five guys that were really involved in that. One was [Dan Klute?], who is dead.

[00:28:08] RB: I've seen the name, yeah.

[00:28:10.] The other one was—he was at Rocketdyne—the other one was Paul Castenholz at Rocketdyne; and then another guy was Dave Harrje, who's H-A-R-R-J-E; at Princeton University; and Professor Luigi Crocco, at Princeton University.

[00:28:33] RB: How do you spell his name?

[00:28:34] JT: Luigi? How to spell Luigi?

[00:28:41] RB: Yeah, I got Luigi.

[00:28:42] JT: Crocco. C-R-O-C-O or C-R-O-C-C-O. And then I was one of the contributors. And the other one was Bob Richmond, here at Marshall. The other one was Dick Crane, at the Lewis Research Center. D-I…

[tape cuts out]

[00:29:26] JT: [inaudible] interesting…that J-2 rigid mesh injector was a kitten compared to that F-1. That was terrible.

[00:29:49] RB: Well, what would you say then was the final fix? These injector baffles?

[00:29:53] JT: That was just one step. It took about three or four major steps to solve the problem. First, we put on the baffles. The next step we did was we slowed down the burning rate in the first few inches of the injection process. We had a LOX like-on-like and a fuel like-on-like, and we went to a smaller inclusive angle so that we spread the fuel out. And, you know, if this is the combustion process down here, the fuel was on about, say, 93—I don't know if that's quite what it was, 97—but anyway, our barnyard philosophy told us that if were we to slow down the burning process, we might desensitize the injection process, so that when these [ratings?] came back, we weren't really in the critical process up near the injector face. We decreased that angle, spread out the burning time. That was the second major step.

[00:31:28] JT: The third step was that we found that we wanted to change the response time between the LOX and the fuel system. We opened up the diameter of the fuel holes,
so that when you, you know, perturbate the system, the LOX system would recover quickly.
It was stiff. But the fuel system would recover at a slower rate because it was soft. That's what you want to do. You want to have them recover at different frequencies because if they are recovering at the same frequency, you're putting out a lot of energy. Whereas if they're recovering at different frequencies, you're damping the process. So that was the third step.

[00:32:19] RB: So you opened the diameter of the fuel holes in the face of the injector?

[00:32:34] That's right. And then the fourth step was that we went in around the edges of the baffles where we knew that there were accumulations of fuel, we modified the injection patterns to try and eliminate these fuel accumulations because if you've got a fuel accumulation there, then it's a source of explosion, you know, and perturbation source—triggering device if you want to call it that. That was the way that the thing went.

[00:33:22] JT: I recall one time when Brainered Holmes was running the Saturn program, he called some of us up to Washington into his office, and he was so concerned about this problem that we weren't able to solve. He told us all that he was ready to go to Congress and tell them that we wanted to have a backup propulsion system for the S-I-C. He was prepared to go ask for a solid motor for the backup. He went around the room, and he asked those of us that were there what our own personal feelings were about whether or not we were going to solve this problem. It's pretty dramatic. He was the top man saying that he was ready to go ask Congress for a backup if we told him that we couldn't solve the problem or if we told him we might not solve the problem. He says, “I want you to tell me truthfully how you feel.” So everybody, I guess, expressed ourselves. He says, “Well, I'm going to take your advice and continue the program assuming that we can solve the problem.” Fortunately, we did. It was really something that always sticks in my memory.

[00:34:41] RB: Was Von Braun involved in any of this?

[00:34:43] JT: Nope, he sure wasn't. It was…Hermann Widener was up there with me. It was Herman Widener, myself, and a man who was the project manager at that time [for the F-1?] Sonny Morea. But I was the chairman of this ad hoc committee to solve this problem, and that was the reason that I was there. The other man was there from Rocketdyne—or two men were from there from Rocketdyne—it was Paul Castenholz and their vice-president Joe McNamara.

[00:35:20] RB: Do you have any papers or reports, AIAA things that help summarize this?
I've seen some documents we have, but I don't think of any really specific documents at this time that we've got.

[00:35:37] JT: The only thing I have ever done is written minutes of all the meetings that were held with a small working group to solve a problem that I had. But I've never published any papers on it, and I don't think any of those that were key in the solution ever published any papers either. But I've seen a whole bunch of papers by people who were not directly involved,
but expanded on what I was thinking to solve. Some of them are far from the way it actually was.

[00:36:18] RB: Would it be possible to get a look at those minutes?

[00:36:25] JT: [Inaudible] I think that they were classified at that time, but I’m sure desensitized [sic] now. Hey, Phil, don't we have the old ad hoc committee file on the F-1? In that red, red…?

[00:36:43] RB: I'll tell you what I could do is—if you don't mind—I could take it over to the historical office over here—Akins' office in 4200—and work on them there and leave them there then when I'm done. When I'm finished with them all, I can bring them back to you. Would that be acceptable?

[00:37:03] JT: That's the only record that exists as far as what took place. I saved it all these years. But what it is, I figured I’d write how it really was. [laughs]

[00:37:14] RB: [laughs] Yeah, I wish you would. You got to do that. Well, I really feel guilty I'm keeping you from this meeting.

[00:37:22] JT: I know they're not getting too far on solid motor materials. [both laugh]
We don't know what it would look like yet.

[00:37:34] RB: Do you have anything else you'd like to throw in here?

[00:37:37] JT: Let me ask you, what are your objectives? Is to fish out maybe significant happenings during the course of the Saturn program? Or are you just going to simply cover the whole waterfront?
[00:37:53] RB: Well, I'd have to say yes to both of those that way we're trying to, you know, cover as much as we can along the waterfront, and...

[00:38:06] JT [speaking to third person, third person is inaudible]:I think it's a whole series of folders, aren't they? Yeah, how many is it?

[00:38:16] RB: As time goes along though we find certain things. We've got an opportunity to do it, to dig down, you know, here and there. It just depends kind of on what we stumble across, even the documents in an interview like this one [inaudible] we can maybe go into it in more detail, but…

[00:38:34] JT: The reason I was asking that, I do a little writing myself [inaudible] ASI line, the augmented spark igniter.

[00:38:46] RB: I talked to Jerry Pease about that.

[00:38:48] JT: Who?

[00:38:49] RB: Jerry Pease. Or Bob Pease. Bob Pease. What really strikes me is that for all the vacuum tests, etc. that were supposedly done on the J-2 up to that time, why that, you know, still happens. As I understand it, it was because the environment of the vacuum chamber—I'd forgotten what he told me now—was different just enough so that it allowed some of this moisture to collect. When they finally purged the environmental chamber down to a really cold, hard vacuum, they found out what the problem really was.

[00:39:26] JT: Yeah, that one was exciting. But you know that ASI line problem had to be not only did we have to understand what failed, we had to understand how it had failed and why it had failed. And then we had a [inaudible] requirement, and that was to reproduce the process here on the ground. In about a four month period, why, we went through all four of those things, and I happened to have been the chairman of that investigation.

[00:40:17] RB: I didn't know that either.

[00:40:19] JT: When you told me you had talked to Bob Pease, I was kind of wondering a little about that because...

[00:40:23] RB: You know, some of this stuff, we're re-writing a lot of this stuff, and I've gotten off engines. Now, I'm into logistics recently. I've kind of forgotten really because I haven't written up that interview yet, what we really got into now. Because I think about it, I think that maybe he did, you know, mention your name in several others. Wasn't Sonny Morea in on that one too?
Or was that the F1? Maybe it was...

[00:40:46] JT: Sonny was the project manager of the J-2 at that time.

[00:40:48] RB: Yeah. Or maybe that's…he just mentioned it in that context then.

[00:40:54] JT: But we had about a two hundred man activity going in NASA and the industry combined. We had a test stand going on at Rocketdyne, firing engines trying to re-create the problem, testing components, and so…But Rex Bailey who works over in the propulsion division and I and Karl Heimberg set up a thrust chamber over here in Bill Grafton's test stand, and that's where we recreated the failure was over there.

[00:41:28] RB: Okay, so right over here was really the critical discovery point then? Right here on this test stand?

[00:41:34] JT: Yeah. Sure was. We recreated the failure. As a matter of fact, I had a thing on the wall, but that thing right there, we simulated the failure right over here. We fired at about eight o'clock one night.

[00:42:00] RB: Now did you have a vacuum condition out there?

[00:42:03] JT: No, because it wasn't necessary to have a vacuum to recreate the process that, you know, where the engine progressed to the point where it quit running. First of all, you had to create a vacuum here in the outside of this line so that there was no moisture condensation taking place. Then this line would fail due to convolution fatigue. These convolutions there, you know, failed in the [inaudible] due to fatigue, and a crack opened up, and the hydrogen shot out this way instead of going into the ignitor. When the hydrogen didn’t go into the ignitor, then the face of the injector was under-cooled [sic] and it got a hot spot on it. Then like blowtorch it started to consuming itself and the failure worked back until the injector face sort of caved in. Well, it's that part of the recreating of the series of circumstances that we've performed over here. It was Rocketdyne who, during the course of the investigation, stumbled across the fact that the environment was very important in terms of life of this convolution here.

[00:43:36] RB: Okay, so let me try and get this straight then. Rocketdyne first discovered
the environmental factor.

[00:43:41] JT: That's right.

[00:43:42] RB: Okay. And then you recreated the environmental factor out here?

[00:43:46] JT: Well, we recreated the failure process. You know, to go back first, General
Phillips says, “You gotta prove what happened.” So we showed him this happened: that line failed. He says, “How did it fail?” It failed due to fatigue. He says, “Why did it fail?” It failed because of the environment around there. It caused high frequency vibrations in it. Then he says, “Now you recreate the events like that engine saw in flight.” Well, it's that fourth thing that we did over here. Rocketdyne stumbled across the fact that the environment was critical to the fatigued life of those [bellows?]. That two hundred man operation was, like I say, active for about four months, and we got the solution.

[00:44:54] RB: That was both Marshall and Rocketdyne, the two hundred man crew?

[00:44:57] JT: Yeah, it was Marshall, Rocketdyne, North American, and Douglas—all four combined effort—was 200 men.

[00:45:07] RB: Sounds like it was, you know, getting to the stage of another crunch like Brainerd Holmes might have called you back up again for another session. Of course, it was a little late then. [laughs]

[00:45:18] JT: Well, we had something nearly like that because during the course of that four months, we had these things called [inaudible] what they do now, but the Boeing building down in the Research Park, they had a room that would go in and sit down, and TV shows all over the country to other groups. We'd have to go down there about once every three weeks or something and give a briefing on where we were in this investigation. That darn thing, I don't know, I mean, it must have been a thousand people on that hookup, because they had
people at Boeing Seattle; people at out on the west coast of Los Angeles within that; people down at KSC; people in Houston; people in Washington. It was like a Walter Cronkite news broadcast.

[00:46:18] RB: Why did they have such an extensive hookup? Was it just to let other people know in terms of their own scheduling or because of the inputs they could make from a technical standpoint?

[00:46:26] JT: No, it was a management review, and all the management should know was, you know, was very concerned, because we were trying to, you know, go manned flight on 504.

[00:46:43] RB: Yeah. 503, wasn't it?

[00:46:46] JT: 504.

[00:46:47] RB: Okay.

[00:46:49] We were trying to go manned flight on 504—502 had messed up. They were kind of wondering whether to delay the flight of 503, until we had absolutely proven the solution. And if they delay 503, they delay 504, and then they delay the whole lunar program. So that's why all them people were interested. But it was on that same flight—if you recall— we had the first POGO problem on S-I-C.

[00:47:20] RB: On 502, yeah.

[00:47:22] JT: So we had Erich Goerner, who was in charge of the POGO investigation. He had a whole team, and all over the country and I had this ASI line [inaudible].

[00:47:36] RB: How do you spell…is it G-O-E-R-N-E-R, Goerner?

[00:47:41] JT: G-O-E-R-N-E-R. Erich Goerner.

[00:47:48] RB: Yeah, I think there was…503 was the first manned flight—that was Apollo 8.

[00:47:53] JT: I didn't know it was.

[00:47:54] RB: Yeah, 504 was the manned suborbital flight. 505 went back to the moon. 506 [inaudible].

[00:48:00] JT: Well, if it was, then the whole bet was, do we dare put men on the bird that lost three engines and had POGO on 502. That's why they were all sweatin’.

[00:48:13] RB: Were you sweating when that man launch finally came then or were you pretty sure that it was going to go?

[00:48:19] JT: I sweated every time it flew, hoping nothing happened with propulsion system. [both laugh]

[00:48:28] RB: As far as the Saturn V missions, that was the only really big problem that you had that was on 502—as I recall—POGO and the ASI line. They both happened at the same time.

[00:48:40] JT: That's right. And of course, those all fell heavily in the propulsion area, so we had plenty of activity. POGO problem, you know, goes back to what the F-1 compliances are the F-1 engine gains, and we had a program going on night and day to run the F-1 turbo pumps and engine [inaudible] factors and all that's going on here looking at the inside line phase parallel for it. It's really exciting.

[00:49:18] RB: [laughs] Yeah, yeah.

[00:49:20] JT: That's the part that really I think people would enjoy reading more about if I were looking into the Saturn...I mean it's great to read about how you land on the moon and all and the [chariots?] run around all over, but good lord they got miles and miles of film about that. The thing that isn't really documented is all of the daily excitements and things that went on during the course of getting there.

[00:49:56] RB: That's what struck me about writing this history: it's that the manned part of the mission is so visible. It's easier to relate to maybe because there are men in it, but the development of the Saturn V and all the testing, static tests, dynamic tests, systems tests and so on, which is such a huge part of the program, is basically unknown. I mean, I take visitors out here to the Space Center and they didn't realize it was the Saturn I and I-B were a bunch of Redstone and Jupiter tanks, you know, hung together. A lot of people just really don't know that much about the Saturn story itself. So I agree with you. [laughs] I hope we can do a fairly good job with it.

[00:50:39] JT: Another one that was really interesting too. One time we were concerned about the H-1 engine and its dynamic stability, perturbation, you know? We'd been running tests up at Joplin, Missouri...

[00:50:55] RB: Neosho was that?

[00:50:56] Neosho. Trying to bomb the H-1 engine and determine if it was truly dynamically stable and everything. And the engine wouldn't really damp in the time that we had laid down for ourselves that it should. So we began to wonder if the test stand up there may have contributed, you know, to lack of desired damp time. So we—Bob Richmond and myself—were working in the area there. We decided that, by golly, the only way you'll ever find out is to put the engine in a stage, then bomb the whole dang stage.

We had an AM-11, [inaudible] be blown today—it’s an S-1 stage. We had it over there on the test stand. We had eight engines in it. It was ready for its acceptance test. I made the proposal that we put bombs in there, and then, of course, during the acceptance fire, we'd get data on the stability characteristics of the vehicle as well, and it'd be a real live flight vehicle, and it ought to be surely good. So we put bombs in four engines. We ran the stage one time, and we had said we wanted three tests, you know, three burns, and we'd bomb every time. Fired the first time, we bombed four engines and watched the damp characteristics. That was good.

For the second time, we bombed four engines, and we blew one engine flat out of that stage over there, and it was on the day before George Washington's birthday. A year, I don't know, two, three, four years, five years ago. Boy, you're talking about a bunch of sick people. So the next day was George Washington's birthday, the holiday and all. But I was over there crawling around in that burned up back end where that engine had burned out. Dan Driscoll was in there, and Karl Heimberg was in there, and Lucas was in there, too. We were all four crawling around up there trying to see what the damage was, see how much delay, and how much expense and everything it was going to take.

And it was that day, George Washington's birthday, that a congressional group was touring here. So naturally, when they hit town, they won't know what had blown up because you don't dare let a congressional group go through here having had an explosion without telling them we had one. So late afternoon, about three o'clock, why, we finally got a story well enough to give and explain to them what had happened and everything that would settle it all. So we began to clean up the mess, of course, we had to put in a new engine, replace all the hardware, and Chrysler was under contract with us. They fixed everything back pretty good. But we still had one more test to make, you know, because I wanted three. Somebody came to me and said, “Jerry, what about it? Are we going to get that third test?” [both laugh] Not on your life. [both laugh] I got all the experience and all the data that I need.

[00:54:34] RB: What stage was this you were testing? It was an S-1 stage?

[00:54:38] JT: No, it was an S-1.

[00:54:40] RB: Oh, an S-1. Yeah, okay. An S-1 then.

[00:54:44] JT: Yeah. With H-1 engines.

[00:54:47] RB: Okay.

[00:54:49] JT: But it was a funny thing, the explosion had not come though anything having to do with stability characteristics. What had happened is when you perturbate the thrust chamber, you know, causing a bomb explosion down there, the flow rates and everything change, and then they have to recover. The LOX pump on one of the engines had a carbon nose ring in it, and when you perturbate the engine, the [inaudible] naturally reacts. And of course it's going at—I think a H-1—around 5,000 or 6,000 RPMs. Carbon being a hard material with these shock loads like that, it cracked. When that cracked, the oxidizer shot through and came in contact with the fuel drain from the other pump. That's where the [explosion?] chain just popped right open. But we've got some good data from the stage from the combustion stability [panel?]. We proved without a doubt that the H-1 has required dynamic stability characteristics. But I never did get that third sample. [both laugh]

[00:56:23] RB: Well, I still feel guilty about your meeting up here. I'm afraid I'm keeping you..

[00:56:26] [inaudible] what it’s like…this is these porch…

[tape ends]

0:56:40