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simulated space environment, and a total of 27 individual tests involving the TV subsystem was performed on the entire spacecraft. Mr. KARTH. These were mostly partial tests?

Mr. KREUZER. These were both kinds. There was the normal complement of space environmental testing, providing stimulus to the input and seeing pictures are received on the equivalent of ground support equipment.

Mr. GURNEY. Mr. Chairman.

Mr. KARTH. Mr. Gurney.

Mr. GURNEY. I think the previous testimony showed that this TV camera was inadvertently tripped off, perhaps by static electricity, or some such thing as that.

Did any of your tests include a test which might have tripped off the camera in this manner?

Mr. KREUZER. To my knowledge, there was no test that simulated this hypothetical static electricity condition that might have tripped it off.

Mr. GURNEY. Are you going to do that on Ranger 7?

Mr. KREUZER. I understand this type of testing will be carried out at JPL on the proof test model for Ranger 7.

Mr. PATTEN. Mr. Chairman.

Mr. KARTH. Mr. Patten.

Mr. PATTEN. Is it true that down on the cape they put the cameras in last, just before they were ready to go?

Mr. KREUZER. That is right.

Mr. PATTEN. You said you conducted thermal tests. Of course, anybody who has ever been in a TV studio has always been aware of the heat problem, and even if you operate a lamp in an ordinary motion picture projector, the heat problem in the ordinary living room will get you.

I think we were led to believe here that on account of the pyrotechnics and other things connected with this satellite that the actual thermal conditions were not simulated insofar as the TV was concerned. Apparently, everything was all together, the cameras were put in last, and then the shot went off.

Is it possible that your bogey man here is a thermal problem that would melt the connections, or cause a short, or do you think that has been explored sufficiently, and are you satisfied it wasn't the cause of the trouble?

Mr. KREUZER. I think, Mr. Patten, we have suspected almost everything I have heard advanced these last several days, and I think we are reasonably satisfied it could not have been this type of thermal problem.

Mr. PATTEN. What is the power you have in these lights for the TV Someone said 60 watts.

Mr. KREUZER. I believe you are referring to the test lights inside of the shroud that are flashed.

Mr. PATTEN. Yes.

Mr. KREUZER. I am not sure of the wattage. They are of nominal type, flashed very briefly, and it is a type of test that we have run before, consistently made and showed satisfactory results. We are sure the payload subsystem was in good condition when it left at launch.

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Mr. PATTEN. Thank you.

Mr. KARTH. Mr. Kreuzer, if you had been the prime contractor, would you have conducted the tests on Ranger VI relative to the static electricity problem that we suspect was the cause of the trouble, and as Ranger 7 is now going to be tested?

Mr. KREUZER. At the time of Ranger VI, I would not, Mr. Chairman, have done anything different than JPL did. This is a possible theory that has come to us now in the aftermath of the difficulty with Ranger VI.

Mr. KARTH. Did you ever experience this difficulty with Tiros, for example?

Mr. KREUZER. No, Mr. Chairman, we did not.

Mr. KARTH. Was the circuitry of Tiros relatively the same as it was in Ranger VI?

Mr. KREUZER. The missions were so different that it is difficult to answer that. In terms of some of the smaller assemblies, yes; in terms of the spacecraft, no, sir.

Mr. KARTH. Those areas suspected today, were those areas eliminated in Tiros?

Mr. KREUZER. May I have the question repeated, Mr. Chairman? Mr. KARTH. Those areas that are suspected of causing trouble in Ranger VI, were they eliminated by you as the contractor for the Tiros spacecraft?

Mr. KREUZER. If, for example, we are considering a possibility of a static buildup on the launch vehicle, there is no specific provision to guard against this in Tiros. We have never had this experience with

it.

Mr. KARTH. How about the switch?

Mr. KREUZER. The Tiros switching system is somewhat different, Mr. Chairman. It is a redundant system, but frankly it is not as redundant as Ranger VI was. In many ways, Ranger VI was the most redundant system that we have built.

Mr. RIEHLMAN. Mr. Chairman, could we get an explanation so that we could understand the difference between the control of the Tiros cameras and those of the Ranger?

Mr. KREUZER. Well, the Tiros cameras are programed for orbital performance over a long period of time, and we have some craft that operated in excess of a year. The Ranger mission was, of course, a very short one, as has been amply discussed.

The Tiros system uses normally two completely separate camera systems, but they are powered by a single battery. The outputs of the two cameras systems again feed a common transmitter and a common antenna, so that there is again a question of redundancy that in my opinion is less than that in Ranger.

Mr. KARTH. Well, forgetting power, and just talking about the system, would you say Tiros was more redundant than the Ranger system?

Mr. KREUZER. Mr. Chairman, I think it would be the other way around, in my opinion. The Ranger is more redundant than Tiros. Mr. KARTH. But forgetting about the power supply, would the Tiros system be more redundant than the Ranger system?

Mr. KREUZER. If the power supply consideration is omitted, perhaps the systems become more comparable, but they both still couple into common output antennas.

Mr. KARTH. Did you ever recommend that a common component be eliminated and that you have a completely redundant system? That is, of the six cameras, you have three of them equipped with separate switching systems so that if one did fail, or arc out, whatever the failure might have been caused by, that the other system could then be relied upon?

Did you recommend such a system as that at any time?

Mr. KREUZER. I think, Mr. Chairman, as a recommendation, it did not take place. I am certain I participated in discussions in which this type of technical procedure was discussed.

Mr. KARTH. Was it a vetoed suggestion?

Mr. KREUZER. No, sir.

Mr. KARTH. In other words, RCA, even though they suggested it, didn't feel so strongly about it that they recommended it?

Mr. KREUZER. Mr. Chairman, I think that is correct. The two technical teams had been working together closely, and day-by-day discussions of this type are made by one side or the other, they are discussed and resolved in the normal course of our activity.

Mr. KARTH. You did not have complete redundancy for the twocamera systems, as a matter of fact, did you?

Mr. KREUZER. In that respect, and certainly in other respects, too, as you have been indicating.

Mr. DOWNING. Would the chairman yield.

Mr. KARTH. Mr. Downing.

Mr. DOWNING. In the Rangers IV, V, and VI, which were near misses and one of which impacted, were the cameras turned on?

Mr. KREUZER. Our intimate experience, sir, is with Ranger VI. On Rangers IV and V a different, smaller, simpler camera system rode as a passenger on the bus, and I have no immediate knowledge of what was done with them.

Mr. DOWNING. You do not know whether it was turned on or not? Mr. KREUZER. I do not know; that is right.

Mr. KARTH. In the area that you and I were discussing, Tiros did have redundancy. Am I correct in making that deduction?

Mr. KREUZER. I think I would like to consult with one of my associates on this particular matter, if I may, please.

I will attempt to clarify to the extent I can, on this situation. There is a heavy switching current that must be handled in Ranger, and a very much lighter one in Tiros. Some of the redundancy in Tiros comes from the fact that we have time working in our favor. We have redundancy provided by time. If we have failure of one side, we can use the other side any number of orbits later.

Mr. KARTH. The Ranger shot that passed the moon some 23,000 miles away, or whatever it was, were those cameras ever exercised? Mr. KREUZER. Those other type cameras were thoroughly tested environmentally at our plant before delivery to JPL some time in advance.

Mr. KARTH. I mean, Were they ever exercised in flight?

Mr. KREUZER. I am sorry, I do not know this, Mr. Chairman.
Mr. KARTH. Does your associate know?

Mr. KREUZER. I don't think anybody in RCA really knows this. We did not participate in the actual exercise and launch activity as we did in Ranger VI.

Mr. KARTH. So you don't know if they were actually exercised after the launch while they were in flight?

Mr. KREUZER. That is correct, sir.

Mr. KARTH. Thank you.

Mr. Gurney.

Mr. GURNEY. In the testimony yesterday, it was developed that there was a way to turn the cameras off from the ground if they were inadvertently turned on in the air, and also that some improvement is going to be made in this system in the transmission of the signal from the spacecraft back to the earth to establish that this fact has occurred. Has any thought been given to an automatic cutoff within the spacecraft of cameras inadvertently turned on, or is that feasible and can it be done, or have you thought about that?

Mr. KREUZER. I don't believe I have thought about it personally. I would feel certain it would be one of the matters that was considered. The problem I think we face with this type of turnoff is the great concern that we reduce reliability, that we have a system that under some momentarily transient condition would turn off and stay off for an important part of the mission.

Mr. GURNEY. Well, that came out in the testimony yesterday, and it developed that the system was such that you really couldn't turn it off without knowing that it had been turned on, and there was no way of being sure. However that is being corrected, I understand.

Mr. KREUZER. That is correct, sir.

Mr. GURNEY. I still say, might it not be feasible to investigate the other part of it?

Mr. KREUZER. I think it is feasible to investigate it, Mr. Gurney. I think that every one of these ideas-and believe me, my associates have come up with many, as have the JPL people always do raise some question of additional components after questions of reliability and changes after a very thorough program of testing. We are usually very loathe to make them.

Mr. GURNEY. I realize that, but I also realize that apparently we are talking about the failure being in the inadvertent turnon of the cameras. This is established, isn't it?

Mr. KREUZER. This is a strong opinion held on the subject. I would not quite say it is established, sir.

Mr. GURNEY. I see.

Mr. KARTH. Did Rangers IV and V have a similar type switching system and similar type circuitry, do you know, Mr. Kreuzer?

Mr. KREUZER. I don't know, but if I could again point out that the camera was so different than the six camera subsystem that I would not expect it to be too parallel.

Mr. KARTH. Was the camera system a much more simple system on Rangers IV and V

Mr. KREUZER. Yes, sir.

Mr. KARTH. In what way was it different?

It did not re

Mr. KREUZER. It was a single camera in each case. quire all of the additional facilities to provide the same type pictures and coverage as the complete subsystem.

Mr. KARTH. So that insofar as the turnon system is concerned, which would appear, or which you appear to be somewhat unfamiliar with, this was not one of your responsibilities.

Mr. KREUZER. That is correct, it was not our responsibility.

Mr. KARTH. I wonder if I could ask Mr. Parks at this time whether or not the camera system was ever exercised during flight on Rangers IV or V?

Mr. PARKS. On Ranger III, the original camera which was quite different from the camera that was flown in Ranger VI-it was a single camera, as pointed out, whose objective was to obtain pictures whose resolution was nowhere near as good as the cameras that we are trying to fly on the block III, of which Ranger VI was one-was turned on for the period of time late in the flight as the spacecraft flew by the moon.

The Ranger III was on a trajectory which would not have caused it to impact the moon, and they were turned on.

We did get back data which indicated that the cameras were generally working-we could see the fiducial marks on the caliberation front of the TV pictures, themselves. It turned out the spacecraft was not looking at the moon, as best we can tell. This is the one in which the pitch maneuver continued, and we were not able to determine exactly what the attitude of the spacecraft was, so we do not get pictures of the moon.

We did have the TV on and did have indication that the camera was working.

Mr. KARTH. How about Rangers IV and V, and how about in particular the shot that missed the moon, which was not intended as a miss.

Mr. PARKS. That is the three that I am talking about.

Mr. KARTH. How about the one that hit the dark side of the moon? Mr. PARKS. On that one, all of the spacecraft equipment was not operating, including the camera, and there was no way to turn it on. Mr. KARTH. Thank you very much.

Mr. GURNEY. Mr. Chairman, I wonder if we could have for the record a statement about the explanation of the turnoff of the camera, and the fact that whatever you are doing to improve this device in Ranger 7 is adequate, and why?

Mr. KREUZER. I think, Mr. Gurney, we believe it is adequate and superior, because there are two commands now-one to turn on, one to turn off, and there is no question about having to rotate to several positions to know whether we are on or off, this in itself raising some problem.

Mr. GURNEY. What about the signal from the spacecraft to the earth to tell whether the camera is on or not? Do you think that that is sufficiently reliable?

Mr. KREUZER. Mr. Gurney, there are indications, as there were in Ranger VI in terms of the RF signal which is visible at the ground stations, to tell that the camera is on.

In addition, on Ranger 7 a further improvement has been made to make this as definite as we know how.

Mr. GURNEY. Are you satisfied that it will be reliable enough to tell you whether the cameras are on?

Mr. KREUZER. Yes, sir; we are satisfied with this.

Mr. PATTEN. May I ask a question here?

Mr. KARTH. Mr. Patten.

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