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Mr. PATTEN. Throughout this whole matter, I take it that as far as the state of the art of TV itself, the picture, that that isn't what attracts your attention. You are talking about the system, the circuits, and everything else, right?
Mr. KREUZER. Yes, that is correct.
Mr. PATTEN. What I have in mind is that in 1959 the Russians took a picture of the back side of the moon. Insofar as the last 5 years goes, there is nothing in the development of your TV cameras, as such, which is important in our discussion here, and you believe that you have developed that art?
Mr. KREUZER. I think we have given an excellent demonstration of this with the performance of the Tiros spacecraft. The pictorial quality has been considered very fine.
Mr. PATTEN. Your whole attention here is how to tie in the circuits and things of that type.
May I ask you one other question? You said you had 27 individual tests involving the entire subsystem on the entire spacecraft. Was that in the lab, on the pad, or was that at Cape Kennedy?
Mr. KREUZER. Most of the tests were in our facilities or the JPL facilities. They were followed up by tests at AMR, at Cape Kennedy. Mr. PATTEN. Did you ever have any test when everything was ready, when you put those TV cameras in the last minute, you are on the booster and are all connected?
Mr. KREUZER. I think this point of the last test using the flashing lights inside the shroud verified that the system was complete and was operating.
Mr. PATTEN. Thank you.
Mr. KREUZER. Shall I continue?
Mr. KARTH. You may proceed, sir.
Mr. KREUZER. The Ranger spacecraft RA-VI was launched from Cape Kennedy, Fla., at 10: 40 a.m., e.s.t., on January 30, 1964. As you know, the primary objective of the mission was not fulfilled since the spacecraft did not transmit television pictures of the lunar surface. Immediately following the impact of the spacecraft on the moon, a JPL-RCA evaluation team undertook an analysis to determine why the system failed to return photographic information.
This joint investigation was carried out at JPL through February 14, 1964, after which the analysis was continued at RCA and, of course, by JPL at its headquarters.
Mr. HECHLER. Mr. Chairman.
Mr. KARTH. Mr. Hechler.
Mr. HECHLER. Mr. Kreuzer, I wonder if you could tell us briefly what you discovered at RCA following the February 4 joint investigation with JPL. What independent conclusions did you arrive at after you continued the analysis at RCA?
Mr. KREUZER. I think, Mr. Hechler, to the extent that we can analyze the limited amount of data that we have from the flight that the real cause may never be clearly known.
Mr. HECHLER. I am basing my question on the last sentence of the paragraph you just read which states this joint investigation was carried out at JPL through February 14, after which the analysis was continued.
All I am asking is: What did you find after the analysis was continued that you had not previously found before then? If the answer is negative, I would be interested.
Mr. KREUZER. I would have to say that we did not find anything definite. As is usual in a technical group continuing to work on the problem, additional theories and possibilities were discussed, but no one of these was definitely substantiated.
Mr. KARTH. Mr. Kreuzer, I wonder if you can list for the record those things that did come to your attention as you continued your analysis. If you can't do it now, you can submit it for the record. Mr. KREUZER. I think I can cover this, Mr. Chairman.
The possibility of some sort of transient triggering the control circuit and inadvertently turning the system on certainly came under our attention.
The possibility of and I don't think this was at all new-any vibration effect causing a relay to chatter. We could never find one that in a subsequent test did do this. The theory has been hypothesized that a static charge might build up on the outside of a launch vehicle shroud, and that at the point of the Agena umbilical connector, which is really two elements down from the TV subsystem, but connected to it, that this external charge might have arced from the cover of the connector to one of the pins in it.
We simulated this in a laboratory test using the parts mentioned, and at least on one or two occasions in a preliminary test did get this kind of an arcing to the connector, but, of course, in a technical way this is far from proving it. It makes it a suspect.
Mr. KARTH. Did you run this kind of a test prior to Ranger VI?
Mr. KARTH. Is there any particular reason why you did not, such as scheduling, that interfered with that kind of test?
Mr. KREUZER. No, Mr. Karth, it was not a question of scheduling. We were not aware of the theory that such a static charge may build up on the shroud.
Mr. RIEHLMAN. Did you give it any simulated test at all?
Mr. RIEHLMAN. Yes.
Mr. KREUZER. Not with relation to the static charge.
Mr. RIEHLMAN. Did you have the equipment to do it with?
Mr. KREUZER. I think that would have to be a matter of interpretation, Mr. Riehlman. We do not have any formal equipment to do it with. We made some simple laboratory arrangements to do it since. Mr. KARTH. Mr. Downing.
Mr. DOWNING. Did you try to reenact or duplicate what might have happened to the camera? In other words, in your suspicion of an arc causing the camera to turn on, did you actually try that in the laboratory?
Mr. KREUZER. On a simulated basis, using just the cables, the large receptacle, and instrumentation in a vacuum chamber so that we could operate at the reduced pressure which exists at this height in the atmosphere, but not, of course, of a complete launch vehicle or anything of this type. We don't have this.
Mr. DOWNING. What were the results?
Mr. KREUZER. The results on at least one test at reduced pressure in the vacuum chamber indicated arcing from the cover of the Agena receptacle to the pin in the receptacle to which the control circuit was connected.
Mr. DOWNING. Did it turn on?
Mr. KREUZER. It gave an indication equivalent to turning it on; yes, sir.
Mr. DOWNING. If the instrument was turned on in flight, wouldn't you have seen a picture back at the laboratory?
Mr. KREUZER. At this point at which we suspect that it might have been turned on, the atmosphere is at a reduced pressure and this is conducive to arcing and voltage breakdown, and it is believed the system was destroyed so rapidly that no picture would result. This was not at a point in the mission at which normal transmission was expected, anyway.
Mr. DOWNING. So you think it was destroyed almost immediately? Mr. KREUZER. Our strongest suspicion, probably never to be completely proven, is that it was destroyed during this boost phase of the launch.
Mr. DOWNING. Would that account for the fact that the station at Woomera couldn't find that it was on?
Mr. KREUZER. I don't know, Mr. Downing, whether the two events would have a connection or not. I think that the station at Woomera simply found it in what appeared to be the normal off condition. I could hardly speculate.
Mr. DOWNING. You feel it was probably destroyed at that point? Mr. KREUZER. So far as the TV subsystem, it is our best opinion that it probably was, sir.
Mr. DOWNING. Thank you.
Mr. PATTEN. Mr. Kreuzer, apparently this is so different in technique in launching that you don't learn anything from the Tiros launching there is no comparability?
Mr. KREUZER. Well, there is a sufficient difference for this type of mission so that perhaps that is a reasonable conclusion. We certainly had never encountered this effect before. We are in a rather strange new medium, and each pioneering flight-and this is certainly one has divulged new effects to us.
Mr. PATTEN. How heavy is the Tiros?
Mr. KREUZER. The Tiros has varied from payload to payload, but I believe an approximate weight would be about 285 pounds.
Mr. GURNEY. In this electrical arcing, I don't quite understand what the theory is about the destruction, because it has always been mentioned in connection with the turning on of the camera.
Do you mean to say that after the electrical arcing and the turning on of the camera, this built up more electricity which melted something or destroyed something? Or was it the original charge from Agena connection to the point inside the spacecraft that did it?
Mr. KREUZER. I think, Mr. Gurney, there may have been some confusion. If this theory which, as I believe I have pointed out is only a theory, that a charge builds up on the outside of the shroud, that arcing to the connector pin which we assume may have taken place is a separate and different kind of arcing than the electrical arcing we have talked about inside the TV subsystem that destroyed the cameras.
The outer one we have called a static electricity charge and arc. The one inside the TV subsystem was arcing produced by its own battery power that it carried, and I think it has been explained, and I would like to repeat, perhaps, that at sea level and in the vacuum of upper space, the equipment would not have been destroyed. Arcing, at normal power would not have occurred. At the in-between altitude where pressure is reduced, it is a rather well known physical fact that arcing occurs much more easily, and we suspect this is where it might have occurred.
Mr. GURNEY. What is the theory on the time interval-a matter of seconds, or minutes; this destruction?
Mr. KREUZER. Oh, I believe no more than seconds, Mr. Gurney.
Mr. GURNEY. What specifically is being done, then, to take care of that, assuming that the TV cameras are turned on inadvertently at this critical place in the atmosphere-what is being done in Ranger 7 to meet that problem?
Mr. KREUZER. I think the two most important things, Mr. Gurney, are the desensitization of the control circuit, and the removal from the umbilical of test leads that ran to the control circuit.
Mr. GURNEY. But the problem is definitely being met?
Mr. KREUZER. I believe it is, and additional testing I understand will be performed at JPL on the PTM to help clarify that.
Mr. KARTH. Mr. Kreuzer, in the letter that Mr. Webb sent to the two chairmen, he says at one point that in the terminal phase, certain sequences of the TV subsystem seemed to operate properly. This was after whatever destructive process caused the cameras not to function.
A moment ago, I heard you say something about this arcing, or whatever phenomenon occurred, as having destroyed the subsystem. Now, if it had been destroyed, how could it have been determined later on that in the terminal phase certain sequences of the TV subsystem seemed to operate properly?
Mr. KREUZER. Mr. Karth, again we are theorizing, but if this type of arcing took place, the term "destroy the TV subsystem" meant in effect parts of it, the parts that would have the high voltages. We would not expect the rotary switch to have been in difficulty from this standpoint, and I think this normal sequence reference refers to the fact that that part still operated.
Mr. KARTH. Yes, but it takes high voltages to run the camera system. Mr. KREUZER. Yes, but not to run the rotary switch.
Mr. KARTH. So really no tests were made after this occurred to see whether or not the cameras were in fact operating even in the most minor sense, is that right?
Mr. KREUZER. I think the only tests that could be made were in effect the repeated commands which turn the system on, to which it did not respond, as we know. There was no other possibility of doing anything at that time.
Mr. KARTH. Thank you.
Mr. DOWNING. Following the chairman's question, you had a warning that something was wrong early in the flight. Why wouldn't it have been expedient to have tried at midflight as a check to see whether the equipment was working properly?
Mr. KREUZER. This was again one of the possibilities that we all considered afterwards and remembered had been discussed at earlier times, too, as again one of the technical alternatives.
After careful joint consideration with JPL, the decision was made to design the system so that the turn-on took place as we neared the
I think in its simplest form, everyone was concerned that any earlier turnon might have introduced unreliability. If we had turned it on, and, for example, for some unforeseen reason couldn't have turned it off, the batteries would have been drained long before we got to the moon, so a difficult choice was made, but I believe it is the same choice we would make again.
Mr. BELL. Could you have done anything about it if you had turned it on, if they found out something was wrong?
Mr. KREUZER. No, Mr. Bell. There is nothing that we have ever been able to consider that could have been done about it at this time. Mr. BELL. So there was nothing you could do?
Mr. KREUZER. This is part of the reasoning that made us decide to go as we did.
Mr. KARTH. But you did recapture Tiros satellites after they had failed to operate on several occasions.
Mr. KREUZER. I am not sure I understand.
Mr. KARTH. You did exercise the Tiros satellites after they had been inadvertently turned off, so that during that exercise you were able to find whatever difficulty apparently did prevail, and the Tiros again became a useful spacecraft. Isn't that a proper understanding of some of Tiros problems?
Mr. KREUZER. It possibly may be the first Relay which had an initial difficulty, not Tiros.
This was corrected, and it became, as you said, a very useful satellite, but, of course, the correction took place after approximately a month. Mr. KARTH. That would have been a little late in this instance. Mr. KREUZER. Yes; not on a 66-hour mission, sir.
Mr. PATTEN. May I ask a layman's question?
Tomorrow your company has to start putting in this UHF band in the ordinary TV set. If this show went on, if the Ranger were successful, would the Russians and everybody have been able to come in and get all the pictures? Would it have been easy for the Russians and everybody else to have tuned in and got the same pictures that we would be getting of the moon?
Mr. KREUZER. No, sir; I don't think from this particular craft because of the directional characteristic of the system and the kind of controls that have existed at the ground stations.
Mr. PATTEN. Is there any relationship between getting a picture back from outer space and our ordinary limitations of 30 channels and these 82 new channels of UHF, or is it more like in radio where you can have tens of thousands of bands?
Mr. KREUZER. I don't think there is any very good connection, in view of the frequencies and the kinds of powers here and the normal type of broadcast operation.