Table of Contents
- Introduction
- Cabin Layout and Handwritten Notes
- Notes in the Lower Equipment Bay
- Navigation and Landmark Tracking Notes
- Miscellaneous Notes
- Notes on Main Display Console
Introduction
CM-107, alias the Apollo 11 Command Module Columbia, aboard the recovery ship Hornet.
(Click on the image for a larger version.)
NASA imageCM-107 has recently been scanned by using 6 separate data sources (laser scanners, photometry) at the SmithsonianÂ’s National Air and Space Museum for a project to produce a very high resolution 3-dimensional model. Resulting imagery reveals various notations written on various surfaces within the spacecraft. Although some of these markings are visible in a few post-flight images that have been available for some time, few have been noticed or given detailed consideration until now.
This page, based on preliminary photographic images taken in the course of the current project and images from the archives, is intended to provide a detailed guide and discussion of the notations we have come to appreciate for the first time. The discussion should prove especially useful once the more detailed 3-dimensional model is released (tentatively scheduled for July 2016).
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Cabin Layout and Location of Handwritten Notes
Cabin Layout
A cut-away diagram of the Command Module.
(Click on the image for a larger version.)When thinking about the Command Module, it is best to think of it as if it were an aircraft with the pointy end forward and the crew seated with their heads uppermost. This goes counter to how the CM is usually depicted (which is lying on its heatshield with the crew on their backs).
In this orientation, 'forward' is towards the pointy end, like the sharp end of an aircraft, and this is the same direction that a seated crew would be looking. Therefore as an example, the part of the heatshield that covers the parachutes in front of the crew is called the forward heatshield (aka apex cover).
Similarly, the main heatshield that absorbs most the the punishment upon re-entry is known as the aft heatshield as it is behind the seated crew. It therefore follows that the equipment that is ‘down’ at the crew’s feet is the in the Lower Equipment Bay or LEB.
The LEB is the location of the spacecraftÂ’s navigational equipment consisting of a computer, an inertial platform, both of which were hidden behind panels, and an optical system that allowed navigational sightings on stars and landmarks. This area was therefore often occupied by the Command Module Pilot (CMP) who acted as the spacecraftÂ’s navigator. It also acted as a semi-private area for bodily functions as well as having storage compartments behind doors.
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Location of Handwritten Notes
Notes were found in two general locations; in the Lower Equipment Bay (LEB) and on the Main Display Console (MDC), the large, semi-circular instrument panel that straddled the cabin in front of the crew couches. This should come as no surprise as both areas were the focus of intense operational activity throughout the mission.
Notes in the Lower Equipment Bay
There are a number of notes written on various surfaces across the LEB. These notes can be broken down into two categories:
- Navigation and Landmark Tracking Notes -- These notes are concentrated around the Navigation Station where the optics and one of the two computer interfaces (“DSKY”) are located.
- Miscellaneous Notes -- These notes include two separate “caution” notes on the B1 and R5 locker doors; a hand-drawn “Jailhouse Calendar” below locker B1 and a tribute to the spacecraft, written on the sextant mount sometime post-flight by CMP Michael Collins.
A cut-away diagram of the Command Module Crew Compartment showing the locations of the handwritten notes described in this entry.
(Click on the image for a larger version.)
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Navigation and Landmark Tracking Notes
Both groups of navigation and landmark tracking notes are located on a door and panel to the left of the Navigation Station in the crew cabin Lower Equipment Bay:
- Navigation Notes
- Navigation Platform Alignment Notes - These notes include the details of calibrations and realignments of the spacecraft's inertial navigation platform resulting from star sightings taken through the sextant. These are associated with computer program P52.
- Navigation Exercises - These notes relate to sextant checks of the spacecraft's position and trajectory, using the computer program P23.
- Landmark Tracking Notes - These notes refer to map coordinates read up to CMP Michael Collins from Mission Control in attempts to locate the Lunar Module Eagle on the lunar surface using the spacecraft's sextant during orbital passes over the landing area. These are associated with computer program P22.
View of the Lower Equipment Bay.
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View of the panel and door area of the Lower Equipment Bay to the left of the Navigation Station.
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Navigation Notes
A view of the door and panel with both the P52 Navigation Platform Realignment and P23 Position Check notes highlighted.
The labelled image above shows six data sets circled in red. Some are related to use of the sextant and computer program P52, and the others to use of the sextant with program P23. We will begin with a general discussion, followed by detailed discussions of the individual data groups. Both the uppermost and lowermost of the six data groups are related to checking alignment of the spacecraftÂ’s inertial platform relative to the stars.
Below is page 111 from the Apollo 11 mission report. It highlights the two times that P52 platform realignments were written to the left of the spacecraft's optics.
List of P52 Navigation Platform Realignments.
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P52 Platform Alignments
In order to check the alignment of the guidance platform, reference had to be made to the stars. Only two were required and Collins used the sextant, a 28-power optical device built into the spacecraftÂ’s hull, to take marks once the instrument had been precisely aimed at each one.
The top two numbers in each cluster are codes for the two stars used. These codes allowed the computer to know which stars were being used for the exercise. A catalogue of 37 bright, well-distributed stars had been programmed into the computerÂ’s memory along with their precise positions. NASA had helpfully affixed a table of all these stars directly below the eyepieces for the optics.
A table of Celestial Body Codes on a decal mounted below the Navigation Station.
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These star codes were in octal rather than decimal form. Mike would enter the star code and ask the computer to drive the optics to aim at that star. By looking through the sextant eyepiece, he could see how far the star was from its expected position by virtue of the inertial platform having drifted. He then carefully moved the sextantÂ’s aim to centre the star and pressed a button upon perfect alignment, thereby informing the computer where the star really was.
Once Mike had done this for two stars, the computer told him the star angle difference, a comparison of the known angle between the stars and the measured angle between MikeÂ’s marks. '00000' for the top cluster was known as 'all balls' and made Mike a happy man for it meant that his aim at the two stars had been accurate to less than one hundredth of a degree. The star angle difference for the lower cluster shows '00001', one hundredth of a degree difference - still considered very good.
The point of the exercise was to realign the slowly drifting inertial platform. For this, the computer calculated the error in its orientation. This yielded three Euler angles by which the platform’s orientation had to be rotated or ‘torqued’ in order to restore perfect alignment with the stars, in thousandths of a degree. These are the next three items in the clusters.
The alignment of this platform was crucial to some of the most important operations of the spacecraft; navigation and engine burns. Engineers were therefore keen to keep an eye on its rate of drift. Mike would bring all three angles onto the three register displays of the DSKY by asking it to display Noun 93. Since the flight controllers were able to see the contents of the DSKYÂ’s display on their consoles, this gave them an opportunity to take a note of them.
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Bottom-left Entry on Bottom Panel
31 & 35
.00001
+000 [crossed out] +00111
P52 +00128
-00014
57:26
This P52 exercise was carried out at 57 hours, 26 minutes into the mission and there is a mention of it in the mission transcripts at: Apollo Flight Journal: Day 3: Flight Plan Updates.
057:19:27 Garriot: 11, Houston. We suggest you go ahead and do the P52 first, and we'll take a look at the angles and give you some new drift rates after taking a look at them. Over.
057:19:37 Collins: All right. Fair enough.
[Long comm break.]
[Dialogue omitted]
057:25:50 Collins: Houston, 11. You're looking at the Noun 93, and I'll proceed when you copy them.
057:26:00 Garriot: 11, Houston. We've got them.
057:26:08 Collins: Okay.
[Comm break.]
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Top Entry on Upper Door
04, 34
00000
P52
+00170
+00342
-00023
96:55
This cluster refers to a P52 that was carried out 92 hours, 55 minutes into the mission. At this time, Neil Armstrong and Buzz Aldrin were extremely busy preparing the Lunar Module Eagle for its landing attempt and thus Collins kept quiet about it. The moment is included at: Apollo Flight Journal: Day 5: Preparations for Landing but there is no mention of it.
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P23 Navigation Exercises
The other triplets of numbers were associated with P23 navigation exercises.
The primary means of navigating an Apollo spacecraft was to use the radio system to provide position and velocity information. However, as a backup, navigation was also carried out by the CMP using the spacecraftÂ’s sextant and P23. As the spacecraft coasted away from Earth and approached the Moon, its trajectory could be determined by taking note of the angles that either of these bodies made with various stars.
The sextant was similar to the classic marinerÂ’s sextant in that it had two lines of sight; fixed and moveable. By aligning the images of two objects using both lines of sight, it was possible to accurately measure the angle between them.
The technique required that Mike rotate the entire spacecraft so that the fixed line of sight was directly aimed at the horizon of Earth or the Moon. He then aimed the movable line of sight to bring the image of a star to coincide with the horizon. A strong filter was included in the fixed line of sight to dim the light from the horizon so that it would not drown out the starlight.
Mike had to let the computer know which star he was using (via the star code list). He also had to indicate whether he was using the planetÂ’s horizon that was nearest to the star or furthest away from the star. It was very possible that the horizon nearest the star would be in darkness.
To aid Mike in bringing the fixed line of sight to bear on the horizon, MCC helpfully supplied a set of attitude numbers and these were evidently written into the wall of the LEB so that they would be handy during the P23 exercise. P23 then used the star horizon angles to calculate the spacecraftÂ’s state vector, a set of numbers that defined its position and velocity at a particular time.
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Middle of Top Door
P52
optics cal
330.5
086.3
000.0An additional set of three numbers near the centre of the upper door is labelled ‘P52 optics cal’ and they defined a spacecraft attitude intended to be used for a P52 exercise and for a calibration of the optics system. When read up by MCC at 022:55:09, they were copied down by Buzz Aldrin. By rotating the spacecraft to the attitude represented by these numbers, Mike should find that the required star is in the sextant’s field of view.
From: Apollo Flight Journal: Day 2: Mid-course Correction
022:54:25 McCandless: Roger. It should be the second step in that procedure. At time 22:40, or when you get to it, we'd like to commence a charge on Battery A. (Pause.) And at time 24:10, we have an updated attitude for your P52 and optics calibration. Over. (Long pause.)
022:55:06 Aldrin: Okay. 24:10. Go ahead.
022:55:09 McCandless: Roger. P52 and optics calibration attitude: roll, 330.5; pitch, 086.3; yaw, 000.0. The nominal attitude that's pen-and-inked in for the P23 is still good. At time 25:30, approximately, after you complete P23, we're requesting a waste-water dump down to a nominal 25 percent. Over. (Long pause.)
P23 included a routine that permitted Mike to check the calibration of the optical system if required. This tended to be carried out early in the mission until he and the engineers became satisfied that the angle-measuring mechanism was working well. The routine called for both the fixed and moveable lines of sight to be trained on the same star. In this configuration, the measured angle ought to be zero and any bias in this measurement could be noted and factored into any future measurements.
The same attitude was used for a P52 platform alignment exercise as it is already pointing at one of the two stars required. It is therefore likely that this was the initial attitude used for a P52 exercise just over an hour later ar 024:14 GET.
Note that although Aldrin copied this at 022:55:09, he may not have written it on the door. He was acting as the copy secretary, taking down changes and updates from MCC. This data was part of a larger batch and one would have expected him to write this on paper. However, the writing style seems a little different to the others which we feel sure are likely Mike's.
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Top-Left of Bottom Panel
198.60
130.7
[all crossed out]
From: Apollo Flight Journal: Navigation and Housekeeping
006:56:17 Collins: And, Houston, Apollo 11. These Auto optics maneuvers or P23s, Auto maneuvers, don't seem to be going to the substellar point. Can you come up with the roll, pitch, and yaw angle for the substellar point on this star? It's our second star.
006:56:31 Duke: Roger. Stand by. [Long pause.]
006:57:21 Duke: Hello, Apollo 11. Houston. Your angles in the Flight Plan we feel are still good; 198.6, 130.7, 340.0. Just slightly off than those in the Flight Plan. Over.
006:57:36 Collins: Okay. We'll try that. [Long pause.]
006:58:28 Collins: Charlie, state those three angles one more time. I'd like to confirm them before I maneuver.
006:58:32 Duke: Roger. Roll and pitch are slightly off than what's in the Flight Plan, 11. Roll is now 198.6, pitch is 130.7. Over.
006:58:47 Collins: Roger. Roll 198.6, pitch 130.7, and yaw 34000 [means 340.0].
006:58:55 Duke: That's affirmative.
When Mike carried out a P23, he had to be sure to point the fixed line of sight to what was called the ‘substellar point’. This is the point on a planet’s horizon that was as near as possible to the star (if using the near horizon) or as far away as possible (if using the far horizon). Mike is expecting the attitude angles given to take the sextant to that point.
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Bottom-Right of Top Door
197.8
128.5
340.0
[all crossed out]
From: Apollo Flight Journal: Navigation and Housekeeping
These numbers refer to another P23 celestial navigation exercise by Mike.
007:35:40 Aldrin: Read you five-by.
007:35:42 Duke: Roger. Same, Buzz. And, 11, the angles for you are 1978 for roll, 1285 pitch, 3400 yaw.
007:35:58 Collins: Okay. Just as a matter of comparison, P23 for this star would like to go to 235.66, 154.31, and 31365. Over.
007:36:15 Duke: Roger. We copy, 11. We understand that the program can give you almost an infinite combination of angles in P23, and it's not too unreasonable. If you'll stand by, we'll look at these that we see on the DSKY. Over.
007:36:31 Collins: Okay. Then in the meantime I'll just go ahead and maneuver to yours. 197.8, 128.5, and 340.0.
007:36:38 Duke: Rog.
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Bottom-Center of Top Door
195.2
123.9
340.0
[all crossed out]
02 [separate, to the left of entry]
From: Apollo Flight Journal: Navigation and Housekeeping
007:58:21 Duke: Hello, Apollo 11, Houston. We'd like you to go back to star number 2 with an attitude as follows: roll, 195.2; pitch, 123.9; yaw, 340.0. Mike, that'll give you a trunnion angle of about 31.4. Over.
007:58:45 Collins: Okay. Understand star number 2 and roll 195.2; pitch, 123.9; and yaw, 340.0. Over.
007:58:57 Duke: That's affirmative.
007:59:01 Collins: Okay.
Mike is continuing with his P23 exercises and is using star ‘02' (Diphda) for the moveable line of sight while pointing the fixed line of sight at Earth’s horizon using the given attitude angles for the spacecraft.
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P22 Landmark Tracking
Command Module Pilot Michael Collins made 7 separate (ultimately unsuccessful) attempts to locate the Lunar Module Eagle on the lunar surface. He recorded some of the map coordinate suggestions as they were read up to him from Houston on the right side of the bottom panel.
The right side of the lower panel to the left of the Optics Station in the LEB
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From the Crew Technical Debrief, regarding landmark tracking:
Collins:
The operation of P22 was easy. The procedures that I had condensed into a checklist on the LEB panel were more than adequate. I always went to P22 early, got AUTO optics, and pointed at the landmark far in excess of 50 degrees trunnion. I sat there with a PROGRAM ALARM until such time as the trunnion angle came down below 50 degrees. At this time, I punched off the PROGRAM ALARM and the optics then began to track. I found this was an easy way to operate the system. I had the center couch underneath the left-hand couch for EVA. It was easy to move from the LEB up to the MDC. I found that window two or preferably window three could be used to give you an idea of where you were relative to the landing site. I could look out either of those windows and see all the landmarks approaching. When I got fairly close, all I had to do was leisurely wander down to the LEB, look through the optics, and be ready to mark. The problem was I didn't know where the LM was, and the ground didn't either. There is too much real estate down there within the intended landing zone to scan on one, two, three, or four passes. On each pass, I could do a decent job of scanning one or two grid squares on the expanded map. That map is the 1:100,000 map called LAM 2. The ground was giving me coordinates in the grid square coordinate system that were as much as 10 squares apart. This told me they didn't really have much of a handle at all on where the LM had landed. As I say, it was just too large an area for me to visually scan. I used AUTO optics each time I looked at the area they suggested. I never did see the LM. I don't have any suggestions for future flights. You have to know with considerable accuracy where the LM is before you can mark on it. If you knew where it was that accurately you wouldn't really need P22 to refine your estimate. Perhaps a different Sun angle would yield the possibility of a flash of specular light off the LM skin giving you a clue. I looked for flashes and never saw any.
Flown CMP Map LAM-2
(Click on the image for a larger version.)
From the Apollo Lunar Surface Journal's Apollo 11 Image Library.
Mike Collins used this map to mark the estimated LM locations given to him by Houston. Compare with the sextant locations plotted in Figure 5-14 (below) from the Mission Report. The grid spacing is 1 km and the actual landing site is near J.65 and 7.52. Scan courtesy Bob Craddock and Allan Needell, National Air and Space Museum.
The landing ellipse is centered at map coordinates L.0/14.0 and extends north and south 2.4 km from that point and 9.4 km east and west. Mike Collins marked a number of locations with combinations of lines, arrows, circles, and one ellipse using either pencil or a felt-tipped pen. Most of these are associated with estimated LM locations that were given to him at various times during his solo operations in lunar orbit.
Beginning at the upper left, there is a penciled ellipse labeled 'Auto Optics' and including craters at N.7/7.2 and M.0/6.7 that Mike mentions at 106:43:08. Owen Garriott gave Mike settings for Auto Optics operation of the sextant at 105:19:59; and, at 106:11:49, about 35 minutes before Mike's next pass over the landing site, Bruce McCandless told him "We'd like you to let the Auto optics take care of the tracking and devote your energies to trying to pick out the LM (visually) on the lunar surface."
The 'Auto Optics' ellipse also contains a small circle at L.7/6.6 and attached arrow from the southwest drawn with a felt-tipped pen. I have not been able to associate this circle with anything in the transcript or in Figure 5-14 (below) from the Apollo 11 Mission Report.
Immediately to the right of the upper end of the 'Auto Optics' ellipse, Mike has drawn circle, probably around the 'tiny crater' at M.7/8.0 that he mentions at 104:42:48.
Below the 'Auto Optics' ellipse, a penciled arrow leads to a circle drawn at K.8/6.3. At 112:22:20, Mike requested an estimated LM position for his pass over the landing site at 112:31:52. Bruce McCandless gave him K.9/6.3 and, as can be seen in Figure 5-14 (below), the actual landing site is just outside the sextant field-of-view for this location.
Below and to the right, an arrow drawn with a felt-tipped pen and labeled 'Last Bst Pos Prior L/O' leads to a dark spot at J.5/7.7, which is the estimated location Ron Evans gave Mike at 123:55:23, about a half hour before LM lift off. This location is only about 230 meters from the actual landing site at J.65/7.52. Farther down the map, Mike circled craters at E.3/7.6 and E.8/7.7 and to the left of the E.3/7.6 crater wrote 'SW Rim'. These two craters are in the area he examined during the pass over the landing site at 110:33:40 using the sextant in automatic mode and a set of coordinates Bruce McCandless gave him at 110:18:39. Mike reported the negative results at 110:36:58 but mentioned a "suspiciously-small, white object" on the southwest rim of the E.3/7.6 crater.
Finally, there is a small, blue dot at about K.2/5.6, which may not have been purposefully drawn.
(Click on the image for a larger version.)
Figure 5-14 in the Apollo 11 Mission Report shows the locations given to Mike in his attempts to find the LM. Each of the small squares is 1 kilometer on a side and the circles, which represent the approximate sextant field-of-view, are each about 3.2 km (2 miles) in diameter.
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Top-Right Entry on Bottom Panel (Point 5)
P22 Point 5
M.7
8.0
From the Apollo 11 Lunar Surface Journal chapter Post-landing Activities.
106:29:41 Collins: Okay. I'll stay on D here for a while. I'm about to go into P22 (a tracking program which keeps the sextant pointed at the targeted spot on the ground while he passes overhead).
106:29:45 McCandless: Roger. Out.
[Long Comm Break]
106:36:16 Collins: Houston, Columbia. I'm coming up on my time for the first pass when I may be able to see the LM. Do you have any topographical cues that might help me out here? Auto optics is tracking between two craters. One of them, as the LM sees it, would be long at 11 o'clock. The other would be short and behind him at 5 o'clock. (Pause) These are great big old craters (or) depressions.
106:36:44 McCandless: Stand by. (Long Pause) Columbia, this is Houston. The best we can do on topo features is to advise you to look to the west of the irregularly shaped crater, and then work on down to the southwest of it. Over. (Pause) Columbia, Houston. Another possibility is the southern rim of the southern of the two old-looking craters. Over.
[commentary omitted][For this second pass since the landing, Houston has Mike looking in an area about 2.5 km north of the first area he examined. Circle 2 is centered at about N.5/7.5 but, as indicated in the transcript and commentary at 106:43:08, the area he examined is shown by the ellipse centered at about M.8/6.9 that he drew on the flown copy of LAM-2.]
[Comm Break]
106:38:42 Collins: Roger, Houston. Columbia. No joy. I kept my eyes glued to the sextant that time hoping I'd get a flash of specular light off the LM, but I wasn't able to see any in my scan areas that you suggested.
106:38:56 McCandless: Roger. On that southern of the old craters, there's a small bright crater on the southern rim. One plot would put him slightly to the west of that small bright crater, about 500 to 1000 feet. Do you see anything down there? Over.
106:39:19 Collins: It's gone past now, Bruce, but I scanned that area that you are talking about very closely, and no, I did not see anything.
106:39:26 McCandless: Roger. Out. (Long Pause) Columbia, this is Houston. Over.
106:40:28 Collins: Go ahead.
106:40:33 McCandless: Columbia, this is Houston. On your LAM-2 map, we'd like to confirm the topographical area in which you were looking on this last period of sightings. As we understand you, you were looking in the vicinity of Papa 7 to November 8. Is that correct? Over.
106:40:59 Collins: Stand by one. 106:41:01 McCandless: Roger.[Comm Break]
[Papa 7 is the intersection of the P horizontal line with the 7 vertical line. The actual landing site is near J0.7 and 7.4; that is, seven tenths of the way from the J line to the K line and four tenths from the 7 line to the 8 line. Note that the lines are a kilometer apart.]
106:43:00 Collins: Houston, Columbia.
106:43:02 McCandless: Go ahead, Columbia.
106:43:08 Collins: One of the craters I was talking about is located exactly at Mike 6.7 (on LAM-2).
[This crater is in the southwestern part of the hand-drawn ellipse.]
106:43:19 McCandless: Roger. We found that one.
106:43:21 Collins: The other one is located at 7...(Listens) The other one is located at 7.2, two-thirds of the way from Mike to Nan.
[This crater is in the northeastern part of the hand-drawn ellipse.]
106:43:36 McCandless: Roger. We believe you were looking a little too far to the west and south. Over. (Long Pause)
106:44:03 Collins: Roger. Understand. I was looking where auto optics was tracking, on the average; and (I) understand that it should have been more to the north and more to the west; actually a tiny bit outside the circle, huh?
106:44:17 McCandless: More to the north and a little more to the east. The feature that I was describing to you - the small bright crater on the rim of the large, fairly old crater - would be about Mike 0.8 and 8.2. Over.
[This crater about 200 meters east of the 'tiny crater' Mike circled at M.7/8.0.]
106:44:40 Collins: Well, just give me your best estimate as to his location in this coordinate system, and I'll plot it on my map and go from there.
106:44:48 McCandless: Roger.
[Long Comm Break]
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Second Entry Down on Right Side of Bottom Panel (Point 4)
P22 Point 4
P.2
6.3
From the Apollo 11 Lunar Surface Journal chapter Post-landing Activities.
107:05:26 McCandless: Roger, Mike. I have the coordinates...
107:05:29 Collins: What's new?
107:05:31 McCandless: Well, what's new is I think we have some more coordinates for you on the LM location. Over.
107:05:41 Collins: Ready to copy.
107:05:43 McCandless: Roger, Mike. Papa 0.2 and 6.3 on your LAM-2 chart. Over.
107:06:02 Collins: Roger. Papa 0.2 and who decimal three?
107:06:05 McCandless: Six decimal three, I say again, six decimal three. (Pause)
107:06:17 Collins: Thank you. Papa 0.2 and 6.3. I'll try it.
107:06:21 McCandless: Roger. (Long Pause)
[The actual landing site is at about Juliett 0.7 and 7.4 (on LAM-2). West Crater is at about Juliett 0.5 and 8.1. Note that each of the boxes on LAM-2 represents a square kilometer. Because of the local terrain rises toward the west, the LM shadow, which is its most visible manifestation, is only about 20 meters long.]
108:47:18 McCandless: Roger. Were you successful in spotting the LM on that pass? Over.
108:47:26 Collins: That's negative. I checked both locations, and no joy.
[See the discussion at 108:42:10. 'Both locations' probably refers to (1) the location P.2/6.3 suggested to him at 107:05:31 and (2) the vicinity of nearly coincident points M.8/8.2 and M.7/8.0 suggested at 106:44:17 and 107:10:15]
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Third Entry Down on Right Side of Bottom Panel (Point 6)
P22 Point 6
E.3
4.8
From the Apollo 11 Lunar Surface Journal chapter EVA Preparations.
108:47:30 McCandless: Okay. If you'd like to look again next pass, we have a different set of coordinates based on the onboard P57 solution of the LM. These are Echo decimal three and four decimal eight. I say again Echo 0.3, 4.8, same chart. Over.
[The actual landing site is about Juliett 0.65/ 7.52. Each of the grid squares is a kilometer on a side and Echo 0.3/4.8 is, therefore, about 4.4 kilometers south and 2.6 kilometers west of the actual spot. As can be seen in Figure 5-14 in the Apollo 11 Mission Report, this is Houston's worst estimate. Bruce will give Mike the Auto Optics settings at 110:18:39, and he will examine the location during the pass over the landing site at 110:33:40 and reports the negative result at 110:36:58.]
[Armstrong - "That was quite a distance away from the point they had been looking. Previously, they had been looking up in the Mike area, which is a substantial distance away."]
108:48:00 Collins: Roger. I'll look there. And, also, how about putting that in your machine and coming out with some coordinates - latitude and longitude over two, and altitude - for P22, so it can help me as best it can.
108:48:14 McCandless: Roger.
108:48:21 Collins: That P22 is still pointing in the wrong place.
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Fourth Entry Down on Right Side of Bottom Panel
P22
+0523
11.710
From the Apollo 11 Lunar Surface Journal chapter EVA Preparations.
108:48:26 McCandless: Columbia, this is Houston. Latitude plus 0 decimal 523, longitude divided by two, 11 decimal 710. Over.
108:48:48 Collins: Roger. Understand plus 00523 and plus 11710. Thank you.
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Fifth Entry Down on Right Side of Bottom Panel
P22
T1 110:26:56
T2 110:32:06
From the Apollo 11 Lunar Surface Journal chapter Mobility and Photography.
110:18:39 McCandless: Roger. I got a P22 Auto optics PAD for you. (Pause)
110:18:53 Collins: Roger. Go ahead.
110:18:56 McCandless: Roger. P22 landmark ID, LM: Tl, 110:26:56; T2, 110:32:06. Three miles south. Time of closest approach, 110:33:40. Shaft 353.855, trunnion 46.495, roll zero, pitch 250, yaw zero. Over.
110:19:53 Collins: Roger. Thank you. Readback not required.
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Bottom Entry on Right Side of Bottom Panel
P22
35
Given its location on the panel below the previous entry, this may be the beginning of an entry intended to be the “Shaft” figure of 353.855 that was abandoned after the first two figures.
Alternatively, it could be reference to Star 35 (Rasalhague) used in one of the P52 platform alignments and be unrelated to the P22 landmark tracking values.
Image of Full Door and Panel
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Miscellaneous Notes
These are the notes found on various surfaces throughout the Lower Equipment Bay
On-board stowage map decals on the wall of the LEB below the Navigation Station.
(Click on the image for a larger version.)
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Locker B2
SMELLY WASTE
Locker B2 door with “SMELLY WASTE” caution written on it.
(Click on the image for a larger version.)
Although there’s nothing listed for it in the “As Flown” Stowage List, locker B2 in the Lower Equipment Bay had originally contained some of the crew’s Pilot’s Preference Kits (PPKs), as per the stowage chart below the Navigation Station in the LEB. On the final day of the mission, during preparations for re-entry, Mike Collins advised Mission Control that the PPKs had been removed and that trash had been put into the locker.
From the Apollo 11 Flight Journal chapter Day 8, part 2: More Television and Stowage for Re-entry.
181:39:12 Collins: On your next page, in compartment B1, we estimate about 15 percent of that food is remaining. In B2 we took PPK out of there and put trash in it. In B3, the 16-millimeter cable, the 18-millimeter lens, and the right-angle mirror are on window number 4. And sorta brings you all up to date.
The “Smelly Waste” note may have been written on the locker door as a caution that opening the door would stink up the closed confines of the crew cabin, and so to open it only as absolutely necessary.
It appears that at, some point, someone tried to erase the note. Engineer John Hirasaki, who was in post-flight quarantine with the crew along with Flight Surgeon Bill Carpentier, and was responsible for the preliminary decommissioning and decontamination of the spacecraft, states:
I did not wipe any of the interior surfaces of the Command Module with liquid disinfectant while I was performing equipment removal, either aboard the USS Hornet or while the CM was stored in the LRL in Houston, Texas.
Rather, he placed in the crew cabin a heater with a chemical block that vaporized for decontamination.
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Locker R5
LAUNCH
DAY
URINE
BAGS
(BUZZ + MIKE [crossed out])
Locker R5 Door with “LAUNCH DAY URINE BAGS” note written on it.
(Click on the image for a larger version.)
Locker R5, located on the upper right-hand wall of the LEB, was the designated storage compartment for a number of utility straps, along with two filter assemblies for the Waste Management System. The handwritten note on the locker door was likely intended as a caution for anyone wanting access to the compartment that two (likely) partially-filled in-suit urine collection bags -- from the period the crew was suited through Earth launch, Trans-lunar Injection and subsequent transposition and docking activities -- had been stowed within. Presumably, the idea behind the note was to prevent the bags from being damaged or breached, or left to float away by an unsuspecting crew member.
It is interesting that the name "MIKE" has been scratched out. This may be because Collins subsequently found an opportunity to remove his own urine bag from the compartment and dispose of its contents by dumping them overboard using the spacecraft`s Waste Management System.
Command Module Re-entry Stowage List for Compartment R5
- O0346. V36-612547 06362AAG8005 FILTER ASSY., Q.D. GAS + LIQ WMS
- O0346. V36-612547 06362AAG8006 FILTER ASSY., Q.D. GAS + LIQ WMS
- O6315. V36-601118-11 06362AAJ0613 STRAP, UTILITY
- O6315. V36-601118-11 06362AAJ0606 STRAP, UTILITY
- O6315. V36-601118-11 06362AAJ0614 STRAP, UTILITY
- O6315. V36-601118-11 06362AAJ0615 STRAP, UTILITY
- O6315. V36-601118-11 06362AAJ0617 STRAP, UTILITY
- O6315. V36-601118-11 06362AAJ0616 STRAP, UTILITY
- O0360. V36-788020 06362AAH5472 STRAPS, IN-FLIGHT RETAINER (GENERAL USE)
In this documention image of the stowage of the probe and drogue, taken at about GET 55:30, Mike's name has not yet been crossed off in the note on the door of the R5 compartment.
(Click on the image for a detail of the R5 door.)
NASA image
In this image of the right couch, taken at about GET 55:40, Mike's name still has not yet been crossed off in the note on the door of the R5 compartment.
(Click on the image for a detail of the R5 door.)
NASA image
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Calendar
The “Jailhouse” calendar, located on the wall of the Lower Equipment Bay, just below compartment B1. The calendar itself is written on the wall, and covered with clear plastic.
(Click on the image for a larger version.)
Another view of the calendar, taken from an angle to avoid reflections off the plastic cover.
(Click on the image for a larger version.)
[Consists of an abbreviated (2-week) July 1969 calendar grid with entries in grid squares through the dates July 16-24th.
All date entries, excepting the final day (24th) have been crossed-out with a full-square X.
The calendar has been covered with clear plastic, which is held in place with grey tape.]
At some point during the mission, a calendar measuring approximately 1.5” x 4” was drawn by CMP Michael Collins, using a felt-tip pen on a wall in the LEB just below compartment B1. The calendar consists of a grid, seven squares across by 2 squares down, with letters denoting the days of the week, Sunday through Saturday, above the grid and “JULY 1969” written below. The grid contains numbers corresponding to dates from Wednesday the 16th (launch day) to Thursday the 24th (splashdown day). Each “day”, except for the last one (the 24th) has been crossed out with two diagonal lines, spanning the full length from opposing corners of each grid square. While the grid itself appears to have been made with the aid of a straight edge, another series of lines enclosing the calendar on three sides appears to have been drawn free-hand. There is no evidence of pencil marks being used to draft the calendar before the marker pen was used. Further study may reveal when the calendar was first drawn on the wall.
The calendar has been covered over with a piece of translucent plastic approximately 4” x 6” and described by curators as a “standard NASA Teflon reinforced plastic”. NASA used a clear Teflon based plastic with an anti-static added. This is a common film type plastic used in many of their applications. It is very tough, thick and can appear slimy after time. However, this piece seems relatively non-deteriorated. The plastic has been folded at a right angle for about ½” along the top edge where it meets the underside of the hinge for the B1 compartment. The plastic material is likely "Kel-F": Polychlorotrifluoroethylene, and its source could be a either a fecal containment outer bag, motion sickness bag, sample bag or some other source from aboard the spacecraft. Further study may reveal the source of the plastic cover.
The plastic has been affixed to the wall using the standard gray tape in common use by NASA at the time. The tape is fiber tape with aluminized coating. The brown discoloration underneath is because the self-sticking adhesive probably has a plasticizer in it which is deteriorating and turning brown from age.
There is a wide smear of marker pen ink evident on the wall, starting among the central group of five “Day” letters atop the calendar grid, running in the four o’clock direction through the grid itself and continuing along the wall, passing underneath and past the tape used to secure the plastic. It is possible that the smear was created early on in the calendar’s existence and that the plastic was then taped over the calendar to prevent further damage. The tape along the right side of the calendar is not as securely adhered as the tape around the rest of the calendar, indicating that the tape on that side (and in particular, the lower-right corner) had possibly been lifted from the wall for access to the calendar and then re-attached after each day had been crossed off.
A screen grab of the Apollo 11 TV transmission at GET 33:59. It shows Mike in front of a just-opened and full food locker. He is holding a sheet of plastic that he has just removed from the locker.
(Click on the image for a larger version.)
NASA image
A screen grab of the Apollo 11 TV transmission at GET 33:59. It shows that the calendar (area circled) had not yet been drawn.
NASA image
A post-flight image showing the calendar and locker B2
(Click on the image for a larger version.)
NASA image
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Note on Sextant Mount
Spacecraft 107 - alias Apollo 11
Sextant Mount with tribute to the spacecraft written by CMP Michael Collins.
(Click on the image for a larger version.)
alias “Columbia”
The Best Ship to Come Down the Line
God Bless Her
Michael Collins
CMP
After splashdown in the Pacific Ocean, the Apollo 11 crew and Columbia were transported to Pearl Harbor, Hawaii aboard their recovery ship, the aircraft carrier USS Hornet.
During the trip, Command Module Pilot Michael Collins returned to the spacecraft via a tunnel connecting it with their Mobile Quarantine Facility (a modified Airstream trailer) and wrote a “tribute” to CM-107 on the Sextant Mount in the Lower Equipment Bay.
In his autobiography 'Carrying the Fire', Mike details the circumstances of the note:
For one thing, it doesn't seem right to abandon Columbia without a backward glance. Our presence in it should be marked somehow. I am not normally emotional about machines, and I consider graffiti the exclusive province of morons in train stations. Despite all that, however, I feel a powerful urge to write on Columbia somehow. Finally, on the second evening, I climb back on board its charred carcass, and on the wall in the lower equipment bay, just above the sextant mount, I write: "Spacecraft 107 -- alias Apollo 11 -- alias Columbia. The best ship to come down the line. God Bless Her. Michael Collins, CMP."
However, Mike's first attempt was not very readable and so, later -- once the crew and spacecraft had arrived at the Lunar Receiving Laboratory (LRL) in Houston to finish their 21-day quarantine period -- he returned to Columbia to overwrite the inscription for posterity.
Engineer John Hirasaki, who was in quarantine along with the Apollo 11 crew and Dr. Bill Carpentier, and was responsible for preliminary decommissioning and decontamination of the spacecraft, remembers Collins's LRL visit:
As I recall, Mike signed the panel when the CM was located inside of the LRL. He visited the CM while I was performing removal of the flight recorder along with the decontamination of the CM interior.
When examined closely, much of the note appears to have been done with two or three passes.
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Notes on Main Display Console
The locations of the groups of notes on the Main Display Console.
Note: This image is of the CM Mission Simulator Main Display Console on display at the NASM.
(Click on the image for a larger version.)
Notes were found on the Main Display Console (MDC) in five different areas. Two groups are in the Flight Control portion on the left side of the MDC; one near the Attitude Indicator and one near the EMS Display Window. The third group of notes is in the central area of the MDC near the Reaction Control Systems control area. The fourth and fifth groups of notes are, respectively, at the top and bottom-right of Panel 3 at the right-hand end of the MDC.
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Notes Surrounding Attitude Indicator
(MDC images in this section have been modified from an image provided by the SmithsonianÂ’s Digitization Program Office.)
There are three groups of notes surrounding the Attitude Indicator, all having to do with powered flight maneuvers.
Detail of the three groups of notes surrounding the Attitude Indicator on the left side of the Main Display Console.
(Click on the image for a larger version.)Wider view of notes on MDC Panel 1
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Left-Top of Attitude Indicator
Detail of notes at top-right of Attitude Indicator.
LOI1 Tig 75:49:50
B/T 6:02 + 10
LOI2 Tig
80:11:36
B/T:17+1
These figures refer to the maneuvers required to get Apollo 11 into the required orbit around the Moon. The task was known as Lunar Orbit Insertion (LOI) and was split into two burns; a long one and a short one.
The term "PAD" refers to "Preliminary Advisory Data": the crew had pre-printed forms on which they could write engine burn times and other data they would need in the event that communications was lost with Houston. The Lunar Orbit Insertion Time-of-ignition (Tig) PAD was called up at 072:51:24 in the Apollo 11 Flight Journal chapter Day 4, part 1: Entering Lunar Orbit and then read back by Armstrong.
The PAD included the time of ignition, or Tig which was 075:49:50. The estimated duration of the burn was 6:02. However, the actual time of the burn would be influenced by the precise performance of the SPS engine. What they were aiming for was a particular change in velocity; and there lay a danger.
The LOI burn would be carried out over the far side of the Moon at an altitude of 60 nautical miles (110 km). However, towards the end of the burn, the shape of the resulting orbit over the near side was getting very close to the lunar surface. Moreover, each additional second of burn reduced the near side altitude by about 6.5 nm (12 km). Since they wished to be in a 60nm circular orbit, an accidental overburn by only 10 seconds was enough to bring their near-side altitude to less than zero; i.e. they would impact the surface.
With this in mind, the LOI maneuver was split in two. The first, large burn did most of the job but was deliberately targeted to leave their near-side altitude at 169.2 nm (313.4 km). Additionally, a note in the Flight Plan instructed them to manually shut down the engine if the first burn lasted for ten seconds beyond the expected shutdown time. This gave some leeway for expected performance variations. This is the reason for the "+10" that was written after the burn time of 6:02.
An LOI-1 Burn Chart from the Flight Plan.
(Click on the image for a larger version.)
The LOI 2 (circularization) burn PAD was read up at 078:58:58 in the Apollo 11 Flight Journal chapter Day 4: Lunar Orbit Circularization.
It was read back by Aldrin. This maneuverÂ’s task was to reduce the orbitÂ’s near-side altitude from 169.2 nm to 60 nm and it would do so with a burn lasting only 17 seconds. As with the LOI-1 burn, the Flight Plan included an instruction on when to manually stop the burn.
An LOI-2 Burn Chart from the Flight Plan.
In this case, the crew should only wait one second after the estimated burn time to manually end a continuing burn.
Wider view of notes on MDC Panel 1
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Right-Top of Attitude Indicator
Detail of the Trans-Earth Injection burn data.
TEI Tig
135:23:42
B/T 2:28
[remainder obscured]
This partially-legible writing refers to the burn for the Trans-Earth Injection burn that was used to leave the Moon and return to Earth. The details were read up as a PAD at 134:01:16 in the Apollo 11 Flight Journal chapter Day 6: Trans-Earth Injection providing a Tig of 135:23:42 GET and burn time of 2:28.
Below the burn time, there seems to be a line drawn and below that, barely discernable, may be three attitude numbers labelled R, P and Y (roll, pitch and yaw). These letters seem to be written directly next to the curve of the instrument. The values given by the PAD are:
R: 181
P: 54
Y: 14
There seems to be a faint ‘5’ next to the ‘P’ and a ‘4’ seems to be discernable next to the ‘Y’.
Wider view of notes on MDC Panel 1
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Right-Bottom of Attitude Indicator
Detail of the mid-course correction burn data.
MCC 5
150:29:55
ΔV 4.8
[obscured, possibly 11 s]
R 075
P 159
[obscured, possibly Y 328]
This cluster of data refers to a mid-course correction burn that was made at the fifth opportunity of the mission, this one during the return coast to Earth.
During a mission, seven opportunities were set aside to allow the crew to refine their trajectory by making small engine burns. There were four on the way to the Moon and three on the way back. Not all of them were used. At regular intervals, radio tracking would permit the spacecraftÂ’s progress to be measured with exquisite accuracy. If the path was deviating from the ideal (perhaps due to fluids being ejected or tiny inaccuracies propagating as time went on), then a short burn would be made to restore them to their ideal trajectory.
This one, for MCC-5, was the first opportunity on the way home and the PAD for it was read up at 148:50:48 in the Apollo 11 Flight Journal chapter Day 7: Leaving the Lunar Sphere of Influence:
148:50:48 McCandless: Apollo 11, this is Houston. I have your Midcourse Correction 5 PAD available when you're ready to copy.
148:50:56 Armstrong: Stand by.
[Comm break.]
148:51:56 Collins: Houston, Apollo 11. Ready to copy.
148:52:02 McCandless: 11, this is Houston. Midcourse Correction number 5. RCS/G&N: 26025, pitch and yaw trim NA, TIG 150:29:54.53; minus 0004.8, plus all balls, plus 0000.1; 075, 159, 328. HA is NA; HP, plus 0023.0. 0004.8, 0:11, 0004.8. Sextant star 03, 090.8, 38.2. Boresight star block, none available. Latitude plus 11.02, minus 172.04; 1180.3, 36275, 195:03:33; GDC align, Deneb and Vega, 007, 144, 068; no ullage of course, four-quad thrusting. Over. Read back.
148:53:51 Collins: Roger. Midcourse number 5. RCS/G&N: 26025, pitch and yaw NA, 150:29:54.53, minus 0004.8, plus all zeros, plus 0000.1; 075, 159, 328. NA, plus 0023.0; 0004.8, 0:11, 0004.8. 03, 090.8, 38.2. NA three times. Plus 11.02, minus 172.04, 1180.3, 36275, 195:03:33; Deneb and Vega, 007, 144, 068; and four quads for the burn. Over.
148:55:17 McCandless: Apollo 11, this is Houston. Readback correct. Out.
[Long comm break.]
The burn used the small RCS thrusters on the Service Module. Tig was 150:29:55, the change in velocity, or Delta-V was 4.8 feet/second (1.5 metres/second) and the expected duration of the burn was 11 seconds. Also written below was the spacecraft attitude for the burn: Roll, 75; pitch, 159; and yaw, 328.
Wider view of notes on MDC Panel 1
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Notes Surrounding EMS Window
(Except where noted, images in this section have been modified from an image provided by the SmithsonianÂ’s Digitization Program Office.)
Detail of the three groups of figures near the EMS window.
Figures are present in three groupings in the area that surrounds the EMS Mylar scroll display on the MDC. These three all have to do with the spacecraftÂ’s re-entry into EarthÂ’s atmosphere at the end of the mission.
Wider view of notes on MDC Panel 1
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Mid-Left of EMS Window
Detail of the arrow drawn to the left of the EMS window.
[horizontal arrow, rightward-pointing towards EMS Window between 5 and 6 values]
The EMS display to the right of this arrow was to help Mike monitor the progress of their re-entry. It was a graph that plotted their velocity on the horizontal axis and their deceleration on the vertical axis. A scribe marked their progress as the scroll moved right to left. The entry PAD informed them that the maximum g-force to be expected during re-entry would be 6.4g, later revised to 6.3g, and Mike has drawn an arrow indicating this value.
By the above photograph, the arrow appears to indicate about 5.6g but the angle of view is giving a false impression. This next photograph, taken shortly after the spacecraftÂ’s return to Earth, gives a better impression of the arrowÂ’s position.
A post-mission view of the EMS Window.
NASA image
From the Apollo Flight Journal chapter Day 9: Re-entry and Splashdown:194:16:57 Evans: Roger. Your Max-g, 06.3; your Noun 60, your Gamma at 400k, 6.48; your range to go on the EMS, 1403.3; and your Retro time for V-circular, 02:14. Over.
Wider view of notes on MDC Panel 1
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Bottom-Left of EMS Window
Detail of the note at the bottom-left of the EMS window.
R[subGO] 1404.5 [4.5 crossed out, replaced above by 3.3]
V[sub10] 36275
The figure of 1404.5 was read up as part of the entry PAD at 191:43:57 in the Apollo Flight Journal chapter Day 9: Re-entry and Splashdown.
It was later updated to a new value of 1403.3:
194:16:57 Evans: Roger. Your Max-g, 06.3; your Noun 60, your Gamma at 400k, 6.48; your range to go on the EMS, 1403.3; and your Retro time for V-circular, 02:14. Over.
This change was reflected on the panel writing. The number represented the distance in nautical miles that the spacecraft was expected to travel from the beginning of the re-entry to landing. One of the counters within the EMS would be preloaded with this value. As the entry progressed, the counter’s display would decrease to indicate the ‘range to go’ throughout their passage through the atmosphere.
The Vio number (36275) is one of two velocities given relating to re-entry. For the crew, it is the more important one. It represents an estimate of their inertial velocity, in feet per second, at the point where Earth's atmosphere will be exerting one twentieth of a g on the spacecraft. The computer uses that point to start P64 which controlled the re-entry until their velocity had dipped below that required for orbit. The reason the crew need it is that it is the number to which the mylar scroll on the EMS (top of picture) is preset as it will start to operate at this point to help them monitor the re-entry.
Wider view of notes on MDC Panel 1
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Above EMS ΔV/Range Display
Detail of the numbers written above the ΔV/Range Display.
10435.6 xx62.x
Above the ΔV/Range display are two numbers, one of which is partially obscured. The first is 10435.6. This was an estimate of the change in velocity (or ΔV) that was to be imparted by the Saturn's S-IVB stage during the TLI burn. It had been deliberately biased to suit the characteristics of the EMS systems. The value was entered into the 'counter' display directly below.
This ΔV/Range display is part of the EMS panel. It provides a backup indication of their change in velocity, the DSKY display being the primary source. The EMS has its own accelerometer and its measurements were not as sophisticated as the computerÂ’s but was useful as a backup. Whereas the computer would display their total velocity during TLI, which would reach 35,575, the EMS only dealt with their change in velocity. The way it worked was that the given value, 10435.6, would be entered into the counter. As the burn progressed, the value would reduce, reaching zero at the time that S-IVB shutdown should occur.
The second number is partially obscured but it should read 3262.8. It is relevant to the Trans-Earth Injection burn that was read up to the crew at 134:01:16 in the Apollo Flight Journal chapter Day 6: Trans-Earth Injection:
The crew entered this figure into their EMS Delta V/Range counter display and, just as with the TLI number, it reduced as the burn progressed.
An important difference when compared to the TLI burn was that the EMS could shut down the SPS engine once the number reached zero, thereby providing a backup means of engine cut-off should the G&N system failed to do so. Interestingly, its value is set slightly low to allow for the extra thrust imparted by the engine after shutdown, a quantity that was allowed for the G&N software. The simpler EMS system did not allow for that and so the flight controllers adjusted for it.
Wider view of notes on MDC Panel 1
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EMS Function Switch
Detail of a selector dial to the left of the EMS Window.
Click on image for a larger version
Note that there is some smearing over both words "Function" on the selector dial to the left of the EMS window. It seems possible that it was wiped at some point with some kind of solvent that dissolved the white paint/ink on the dial.
Wider view of notes on MDC Panel 1
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Notes on Panel 2 of the Main Display Console (MDC)
There are three groups of entries in the central part of the MDC, all of which are related to the spacecraftÂ’s re-entry.
Detail of notes in the central part of the MDC.
(Click on the image for a larger version.)
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Entries on MDC Above Helium Indicators
Detail of notes above the Helium Indicators.
1.54 22400
0.84 18000
These numbers were read up to the crew as part of the Entry PAD at 191:43:57 GET. They relate to a partial skip-out trajectory that Apollo 11 would make during its re-entry through the atmosphere.
In a normal entry, three computer programs are used; P63 prepares the spacecraft for entry, P64 drives the CM into the atmosphere in order to bring its speed below that which would allow it to exit and go into orbit, P67 then steers it towards the landing point and the US NavyÂ’s recovery forces.
Apollo 11Â’s re-entry was different because MCC wanted to avoid rough weather that was developing at the prime landing site. To do this, they invoked one of the two intermediate programs, P65, that was designed to handle a skip-out trajectory, and used it to extend the re-entry path by 215 nautical miles (400 km). Had they used a full skip-out, P66 would then have been used to control the spacecraft during its second re-entry. In this instance, P66 was not required.
The two figures on the left represent the maximum and minimum g-force or drag the crew would experience during P65. The two figures on the right represent the maximum and minimum velocities to be expected at that time. Since the crew will be monitoring velocity and drag on the DSKY during P65, they have written these figures nearby as a reference of the limits to expect for both.
See the entry PAD at GET 191:43:57 in the Apollo Flight Journal chapter Day 9: Re-entry and Splashdown.
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Entries Above RCS Indicators Dial
Detail of notes above the RCS Indicators dial.
.05g - 195:03-34
xxx[looks like ‘80-’] [may be 3-34 or similar]
xxxx [may be 06-57]
xxxx
xxxx195:12:08
This group of numbers is associated with entry events. The top number is the time that MCC expected the computer to sense that they were decelerating at a twentieth of a g, or 0.05g.
For the sake of trajectory determination, the Retro flight controller used an arbitrary height of 400,000 feet (121.92km) and called this Entry Interface (EI). This was stated in the Entry PAD as 195:03:06 (see 191:43:57 in the Apollo Flight Journal chapter Day 9: Re-entry and Splashdown).
However, this did not take the drag effects of the atmosphere into account. For the purposes of controlling the re-entry and steering to a safe landing, the computer based its timings on the moment it detected 0.05g. At this point, it would go from P63 to P64 and start to drive the spacecraft deep into the atmosphere in order to bring their speed below that which could sustain an orbit, were they to exit. 0.05g was also the point when the Entry Monitor System and its Mylar scroll was triggered.
The Entry PAD included an estimate that 0.05g would occur 28 seconds after EI or 195:03:34. This is the time at the top of the list.
Three other times were given in the Entry PAD:
- Estimated time for the start of communications blackout: 17 seconds after EI, or 195:03:23
- Estimated time for the end of communications blackout: 3:51 after EI, or 195:06:57
- Estimated time for the deployment of the drogue chutes: 9:02 after EI, or 195:12:08
The lowest writing is clearly 195:12-08, the time for the drogue chutes to deploy. It seems likely that the two figures in the middle represent the times for blackout.
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Entries Above the Mission Timer Display
Detail of notes above the Mission Timer Display.
195 03 06
195:03:06 is the GET for Entry Interface. Coincidentally, it also turned out to be the time of the spacecraft's final voice transmission before Entry LOS.
From the Apollo Flight Journal chapter Day 9: Re-entry and Splashdown:195:03:01 Evans: And 11, Houston. You're going over the hill there shortly. You're looking mighty fine to us.
195:03:06 Armstrong: See you later.
[Long comm break.]
[Nine minutes of radio silence from Apollo 11 now follow, as the spacecraft is surrounded by ionised gases created by the heat of re-entry. Mission Control starts calling them after 4 minutes.]
A post-flight image of the notes on Panel 2.
(Click on the image for a larger version.)
NASA image
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Notes on Panel 3 of the Main Display Console (MDC)
There are notes in two different areas on the right-side MDC Panel 3; near the top, next to the VHF Antenna Selector switch, and at the lower-right, next to the Battery Charge Selector switch.
Lunar Module Pilot Buzz Aldrin had -- when he and Commander Neil Armstrong were on the Apollo 8 backup crew -- trained for the Earth Launch phase of the mission in the center couch, which is normally occupied by the Command Module Pilot. When Michael Collins joined Neil and Buzz on the prime crew of Apollo 11, it was decided that rather than re-train Buzz for the right-hand couch, that Buzz would remain in the center couch and that Mike would fly the Launch and Earth Orbit phases in the right-hand couch. As a result, the notes made on Panel 3 of the MDC, as verified by the transcript, were made by Collins during the Earth Orbit phase of the mission.
Note Next to the VHF Antenna Selector Switch
A post-flight image of the note on the upper part of Panel 3.
(Click on the image for a larger version.)
NASA image
New image of the note on the upper part of Panel 3.
(Click on the image for a larger version.)
Modified from an image provided by the SmithsonianÂ’s Digitization Program Office
TLI c/o
5:53
There is an entry at the upper right-hand end of the MDC, which pertained to the Translunar Injection burn. At 001:44:30, Capcom Bruce McCandless passed the TLI PAD to the crew. This was a list of numbers that defined the burn that would take them out of Earth orbit and head for the Moon. One of those numbers was the duration of the burn that they should expect their S-IVB stage to make; i.e. 5:47.
It was likely that the engine on the S-IVB stage would slightly under- or over-perform and this time was only a guide. The goal was to achieve a certain velocity. However, in case the S-IVB failed to automatically shut down, the crew had guide notes in the Flight Plan that told them when to force a manual shutdown. Page 3-2a (below) carried a table of actions that the crew should take if the TLI burn were to go awry. One item told them that if the burn were to continue for 6 seconds beyond the time given in the PAD, they should manually shut it down.
TLI Burn Chart.
Six seconds added to 5:47 gave a time of 5:53 which Collins wrote in his field of view on the MDC in order to yell a shutdown instruction to Neil Armstrong if required. Therefore 'TLI c/o, 5:53' means they should force a TLI cut-off at 5:53 into the burn if the systems haven't automatically done so.
From the Apollo Flight Journal chapter Day 1 part 2: Earth Orbit and Translunar Injection:
002:21:56 Collins (onboard): Buzz, I put 39.5 volts over here. That's a reminder on the battery check - real good on the wall. Okay, Neil, now TLI: I'm going to write on the wall here - TLI - nominal is 5 plus 47. And 6 seconds later, it's 5 plus 53. And you want me to let you know when that is? I'll yell cut-off at that time.
002:22:27 Armstrong (onboard): Okay.
002:22:38 Aldrin (onboard): Now, we want to get what that time is going to be up there.
002:22:41 Collins (onboard): Is that right, Neil?
002:22:43 Armstrong (onboard): Yeah, that's right. 5:53, I want it yelled.
002:22:45 Collins (onboard): Okay. I'll yell cut-off, huh?
002:22:57 Armstrong (onboard): Yes, I guess. And I'll cut off if the G&N says...
002:23:04 Collins (onboard): Agreed.
002:23:05 Armstrong (onboard):...we're over-burned.
002:23:06 Aldrin (onboard): That's right.
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Note Next to Battery Check Switch
Note on the lower part of Panel 3 next to the Battery Check switch.
(Click on the image for a view of the wider area.)
Both the cropped image above and the linked image have been modified from an image provided by the SmithsonianÂ’s Digitization Program Office.
39.5V [partially obscured]
The Systems Management section of the Operations Checklist discusses the Electrical Power System. Item 5 on the checklist has to do with charging batteries. It includes an instruction to turn the Battery Charge selector switch to OFF at 39.5 vdc or at 100% charge. Mike has written this number on the panel next to the switch as a reminder.
Battery Charging BAT A(B)
cb ECS RAD HTRS OVLD - close (verify)
MAIN BUS TIE A/C (B/C) - OFF
cb BAT BUS A & B PYRO BUS TIE - open (verify)
cb BAT C BAT BUS A & B - open (verify)
cb BAT RLY BUS BAT A(B) - open
DC IND sel - BAT CHARGER
BAT CHARGE - A(B,C)
DC VOLTS - 37.5 - 39.5 vdc
BAT CHARGE - OFF at 39.5 vdc or 100% recharge
cb BAT RLY BUS BAT A(B) - closed
SYS TEST - 4A (BAT VENT *If >1.5: BAT VENT vlv -*
*VENT (to ~0) then CLOSED*
SYS TEST - 4B
From the Apollo Flight Journal chapter Day 1 part 2: Earth Orbit and Translunar Injection:
002:21:56 Collins (onboard): Buzz, I put 39.5 volts over here. That's a reminder on the battery check - real good on the wall. Okay, Neil, now TLI: I'm going to write on the wall here - TLI - nominal is 5 plus 47. And 6 seconds later, it's 5 plus 53. And you want me to let you know when that is? I'll yell cut-off at that time.
002:22:27 Armstrong (onboard): Okay.
Last updated: 2019-08-17Return to Table of Contents
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