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of time is the standard procedure for turning it off if any of the sites (the two overseas ones or the Goldstone one) should see that the TV is turned on. South Africa was prepared, because we saw this inadvertent telemetry turnon, to turn the TV off when it came into view if the indications then confirmed that it was on. They did not confirm that it was on, so we obviously did not send the signal.

Mr. GURNEY. Would there have been enough timelag in the flight of the spacecraft to have one arcing of batteries so they would be no longer functioning? Would that be a reason?

Mr. SCHURMEIER. No, there was enough battery power to operate through that period of time.

Mr. CORTRIGHT. Battery voltage on the way to the moon was normal. Mr. NICKS. I think it should be pointed out again that the turnon was followed very quickly by burnout, if it occurred at that altitude, so whether you turned it off, turned it on, or did anything after the fact—assuming this arcing had occurred-it wouldn't have done any good. The damage was done very quickly after the inadvertent turnon, and there wouldn't have been time to respond to save it if turnon had been noted, in any event.

Mr. KARTH. Mr. Nicks, in Mr. Webb's letter to Congress, he stated that in the design, construction and testing of Ranger VI, "the two video systems were more complex than required.”

Would you agree with that statement?

Mr. NICKS. Yes, sir.

Mr. KARTH. Could you explain to the subcommittee why?

Mr. NICKS. Well, I believe this statement might apply to most electrical circuitry; even early commercial television sets had a lot more things in them than the ones do today.

Mr. KARTH. Is this to provide additional redundancy?

Mr. NICKS. No, sir, I think it is because of the way the design evolves, the fact that the engineers are putting circuits together to do a certain kind of job, approaching an end product, and unless they go back after they have done a design and go over it again and again to remove and modify its functioning elements, almost any complex electrical circuit will have more components than necessary.

The reference here is due to the redundancy in part-that is the different approaches to being able to turn on the system resulted in some extra circuitry that could have been streamlined, and therefore it is a valid criticism, but it again is not an uncommon shortcoming in a design, I think.

Mr. KARTH. Well, the thought that comes to my mind is that perhaps we hadn't really engineered this spacecraft as well as we would have had we not been trying to meet a schedule. Is that a fair statement?

Mr. NICKS. Well, no, sir, I don't think so, although it certainly is true that if you had an unlimited time, or a longer time and desired to refine the system and re-refine it, you could do that. But you don't do that because you have all this elaborate testing program to check out your design. The concept is to try and get the balance between the schedule and the design and the check-out, so you design the thing the best way you can, you ring it out in a test program to see if it works the way you thought, and this is always an iterative process because you always find things which don't work the way you thought. But

in this case the TV passed through the design, and passed through the

test program.

It was the first one of its type, and I think you would expect there to be some improvements possible in a first of a type, but I do not believe it is fair to say that it was compromised from a technical standpoint just because of schedule. The test program was lengthy and thorough to try and make sure that the design would work, and it seemed to do so.

Mr. KARTH. Thank you.

Are there any further questions?

Mr. DOWNING. I have some questions, Mr. Chairman.

Mr. KARTH. Mr. Downing.

Mr. DOWNING. In regard to the Hilburn Board recommendations, who is Mr. Hilburn?

Mr. NICKS. He is Deputy Associate Administrator of NASA.

Mr. DOWNING. Well, now, if I interpret his report correctly and the recommendations and the actions taken, his recommendations were evaluated but dismissed for the most part.

Mr. NICKS. No, sir.

Mr. DOWNING. I don't say that is wrong

Mr. NICKS. I wouldn't agree with that, sir. This is divided in three parts. A part on which we have total agreement, a part on which changes would be made if practicable, and a part where changes were recommended that are still under study and may or may not be followed for other reasons.

Mr. DOWNING. Well, his recommendation 2(a) states that a properly applied and qualified relay would be a better control than silicon. Yet the action listed does not follow the recommendation because no acceptable qualified relay has been located and because the evidence indicates that the silicon is acceptable.

Mr. NICKS. Yes, sir.

Mr. DOWNING. So you didn't follow it in that case.

Mr. NICKS. If you read that statement 2 carefully, it says "if properly evaluated and qualified." I don't believe the Board would recommend putting in an unqualified relay, or one that was not designed to fit the circuit. They are pointing out that fundamentally, in their judgment, a relay is a better kind of switch than a silicon control rectifier, but they make the point that this must be properly evaluated and qualified and, as the action states, we are trying to pursue that path as a parallel to the improvement of the silicon control rectifier.

It might be, if we can achieve the proper qualification and evaluation, that relays would be substituted at some later time.

If you look again in specific regard to your first statement, the parts numbered under one were specific design changes that were concurred in by the Office of Space Sciences and the Board. The second group are in the category, that if they can be properly qualified they would be recommended. The last category

Mr. DowNING. I see. You did concur in a number of recommendations. You went into detail on the recommendations that you were either at some variance or disagreement with.

Mr. NICKS. Yes, sir.

Mr. DOWNING. Did you consider the Ranger VI flight successful with the exception of the television failure?

Mr. NICKS. Yes, sir, except we don't qualify successes usually. It is either a success or failure, and we have to say it was a failure. In every other respect, however, I believe we feel it was a good flight. Mr. DOWNING. I thought you always relied on the concept of partial successes.

Mr. NICKS. No; we abandoned that a couple of years ago because of the controversy over that definition.

Mr. DOWNING. Now, what were you aiming at on the moon?
Mr. NICKS. Do you mean what point?

Mr. DOWNING. What was your target?

Mr. NICKS. It was an area near the Crater Julius Caesar, which was on one of these pictures.

Mr. DOWNING. And you came within 20 miles of that?

Mr. NICKS. Yes, sir, as indicated on the crart, and perhaps Mr. Schurmeier can elaborate on this. The conservative impact circle is shown as a 34-mile diameter circle. In other words, they are quite certain it landed within that, and the center of that circle is within 20 miles of the aiming point.

Mr. DOWNING. What was your pinpoint, your aiming point?

Mr. SCHURMEIER. We did not have a real pinpoint.

Mr. DOWNING. I was wondering how you could select one. There is no post up there.

Mr. SCHURMEIER. We selected a point for the calculation but were really trying to land anywhere within an area.

Mr. CORTRIGHT. I would like to qualify that because I think it is subject to misinterpretation.

At the time we decided to make a midcourse maneuver and selected what that midcourse maneuver would be, from then on we had an aiming point. Actually, prior to making the midcourse maneuver, we designed the midcourse maneuver to land at a certain latitude and longitude on the moon, and that was within 20 miles of that latitude and longitude that it actually hit.

Mr. DOWNING. How did you confirm that?

Mr. CORTRIGHT. By tracking of the spacecraft.
Mr. DOWNING. But it was not possible visually-

Mr. CORTRIGHT. No, sir; we tried to do that, sir, and the astronomers couldn't see anything. In addition, we had telemetry monitoring the midcourse maneuver which we submitted to Mr. Karth's subcommittee during the hearings, which showed the precision with which the Doppler radar record matched the theoretical one. This is another measure of how accurate you are in the total maneuver.

Mr. KARTH. I think, Mr. Cortright, it might be well to make that available for the record at this point.

Mr. CORTRIGHT. Yes, sir; I will be glad to do that.

(The information requested for the record (fig. 33) is as follows:)

[blocks in formation]

DOPPLER DURING MANEUVER OF RANGER VI ON JAN. 31, 1964

[graphic]

· 200

110160

8h.56m:00s

gh:57m:00s

8h:58m:00s

8h.59m:00s

JAN. 31, 1964

TIME - GMT

FIGURE 33

Mr. DowNING. There are 11 planned Ranger flights ?
Mr. NICKS. Nine is the total number.

Mr. DOWNING. We have gone through six, and you are preparing for the seventh. Is the seventh aimed at a different area of the moon? Mr. NICKS. No, sir, the aiming area on the moon is generally an area bounded by plus or minus 10° or 20° latitude.

Mr. SCHURMEIER. It is about a 20° to 30° segment.

Mr. NICKS. A belt along the Equator, and plus or minus 60° longitude. This portion of the moon looks like the best kind of place for manned landings, and it is easy to get to, and we will be trying to get in that region.

The exact point that you choose will depend on the day of launch. Why don't you go into this, Bud?

Mr. SCHURMEIER. Yes. The actual location that we would pick for the impact point would depend on the launch day, because as you move from day to day through the launch period, which is of approximately 7 days duration in a month, the terminator-or the line between the shadow and the illuminated portion of the moon-moves across the face of the moon. For proper lighting conditions to take the photographs, we want to be within between 10° to 40° of that terminator, so this target area moves across the moon.

Mr. DOWNING. But this is a general area which is planned for the manned lunar landing?

Mr. SCHURMEIER. Well, as I understand it at the moment, the manned lunar landing sites are in the maria or flat region, so in general we would try to pick a maria, and as we did on Ranger VI picked one of the maria and impacted right in the corner of that.

Mr. DOWNING. Now, each one of these flights is concerned with television coverage of the surface of the moon?

Mr. NICKS. Yes, sir.

Mr. DOWNING. Why would it be necessary, once you did obtain a good television picture of the moon, say on Ranger 7, to do Rangers 8 and 9?

Mr. NICKS. Well, the moon, as you know, is a large place. If it were possible to conclude that it is completely homogeneous or the same all over, one set of pictures may be enough, but we know it has mountains and craters and flat places and lots of different kinds of terrain.

The Ranger will take its closeup pictures and get the high resolution because it is focusing on a small area of the moon.

Mr. DOWNING. You couldn't possibly cover the surface of the moon? Mr. NICKS. Not at all. It would cover a very small area at the high resolution. It is likely that the first place we take a picture of will not necessarily be the best place to land. We will need a sampling of many areas to determine what is the best from the safety standpoint and

what the nature of the surface is.

Mr. DOWNING. Well, you missed six opportunities to take pictures of various areas. Do you think that you can recoup in your remaining three flights?

Mr. NICKS. Yes, sir. I would like to reiterate that only four Rangers were aimed at the moon. Two tests were aimed away from the moon to get long life in space. We had four toward the moon. We have three left. Yes, sir, we think we have a high probability of success with at least one of those three.

Mr. DOWNING. Will the Lunar Orbiter give you information which would not justify the use of the Ranger pictures?

Mr. NICKS. If it were available today, if the Lunar Orbiter were available and would operate as we expect it to, I think it is fair to say it would replace these Rangers. But there is a considerable difference. The Rangers are doing an exploratory mission. They are developed to the extent that they are nearly working, and for that reason we feel it is entirely justified to go ahead and get this early exploratory data. We know very little about the surface of the moon. These early Ranger photographs could change our views on many things that are under

way.

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