The Predators of Hurricane Gulch

During the course of this summer, my two cats have taken to accompanying my four dogs and me on our morning and afternoon walks. Ono, whom I pulled out of a feral colony in the Fanga 'o Pilolevu district of the Tongan capital city, was the first to join us on a regular basis, and after a few weeks Haisheng, who was born in a Chinese-owned falekoloa (small grocery) in the Kolofo'ou district, and who is less adventurous than Ono, began to come along with us. The sociology of this behavior is interesting to consider, and I wish that my late wife Marilyn, who held a doctorate in sociology, was here to observe and to discuss.

Denzel, Bette, Ono, and Haisheng at the Intersection of Edwards and Marion

While we lived in the Longolongo district of Nuku'alofa, she observed how I developed a cooperative hunting relationship with our first cat Dylan. Our house was crawling with geckos, we often saw them on the walls and on the ceiling, and Dylan chattered at them when they were too high for him to reach. So I took to picking Dylan up and lifting him to where he could better reach the geckos. Sometimes I would throw him against the wall, and more often than not Dylan would land in the floor with the gecko in his mouth. Sometimes I would carry Dylan around the house, tracking a gecko as it moved across the ceiling in an effort to escape us, until it made the mistake of taking a position above a tall object such as the refrigerator, from where Dylan could easily strike. Dylan and I became so attuned to each other that when I heard him chattering, I would immediately come to him, spot the gecko, and lift Dylan up for the kill. At other times, when I spotted a cockroach or a tarantula in the house, I would chatter to Dylan and he would be at my side in seconds to pounce on the prey. Books say that cat chattering is an expression of frustration over a prey beyond reach, but such behavior would have no evolutionary advantage. The chattering makes sense as a survival strategy if one considers that cats can at times choose to hunt cooperatively and to signal the presence of prey to a nearby partner. This is exactly what Dylan and I did, nearly every day and sometimes several times a day.

Dylan Eyeing a Gecko with Bad Intent

During our walk this morning in the Hurricane Gulch section of Sausalito, I was a little surprised when my semi-feral cat Ono crossed the intersection of Edwards and Marion Avenues, and climbed about five meters up the steep hillside in search of prey; but then, in the course of this summer she has become increasingly confident on our walks and she may range ten to fifteen meters from us. What was especially interesting to observe was the excitement with which my dogs reacted to her quick-step trot across the street. It seemed to me that they sensed that Ono was in hunter-killer mode, and that they wanted to join in the hunt, although they couldn't do so because I had them on leashes. They continued to observe her with interest as she prowled about the hillside.

Bette, Jadzia, and Denzel in the GGNRA Above Marion Avenue

One time, during the days I walked the Tongilava Pack off-leash in Fanga, Denzel captured a free-ranging chicken and snapped its neck; he had no objection to my taking it from him. Marilyn was not pleased when we returned home and presented her with the kill; she knew what a chore it was going to be to pluck it. During the next few weeks the Tongilava Pack quickly learned to take down chickens and to devour them, all in a few seconds, leaving only some stray feathers as evidence. At that point, to placate our neighbors, I began walking the Tongilava Pack on-leash; they had become an efficient killing machine. Of course, dogs have been hunting with humans for tens of thousands of years; it is well understood that they include their humans in their pack hunting behavior. But, what I observed this morning tends to support the thesis that my dogs accept Ono as a member of their hunting pack, and indeed, that they appreciate her as a valuable contributor to the hunt.

Ono on the Hunt Above the Intersection of Edwards and Marion

Whether Ono accepts the dogs in her conception of the hunting group is still an open question in my mind. She brings home moles, which she never eats; I imagine that she enjoys catching then but apparently she dislikes their flavor. Ono displays no objection to the dogs eating her mole kills. Ono even brought home a rabbit once, and the dogs ate it in her presence without objection. It may be that Ono views the dogs as being above her in the group's hierarchy, or she may be deferential to them as a matter of prudence due to their larger size. The question is whether Ono brings home her kills exclusively for me, as cats are well known to do for humans, whereas the dogs enjoying her kills is incidental, or whether Ono cares one way or the other as to giving away what she doesn't care to eat.

Haisheng and Ono in the GGNRA Above Marion Avenue

Haisheng eventually crossed the intersection to the hillside several minutes after Ono in that same, low-riding, quick trot of a hunter, although she only climbed about a meter. Was she attempting to join in the hunt with Ono? That's hard for me to say. She is certainly not the hunter that Ono is; if not for Ono, Haisheng would be perfectly happy to be a house ornament. Her favorite activity, or rather the lack thereof, is to curl up with one of the napping dogs; yes, she is wholeheartedly in favor of letting sleeping dogs lie. But, lately Haisheng has begun to bring home kills of her own; sometimes the "puppy cat" exhibits the behaviors of a real cat.

Bette and Her Puppy Cat

I am mindful that my dogs and cats are far from being the only predators in Hurricane Gulch. Much has been written about the coyote threat to domesticated cats and small dogs. Only a few days after we arrived in Sausalito from Tonga early in 2018, Ono escaped from the house. Weeks went by. She had pulled the same disappearing act when we moved from Fanga to Holonga before returning home after three weeks, so I wasn't unduly concerned. She had grown up feral and she could survive in the wild. As the weeks stretched into months, however, neighbors told me that Ono had probably been eaten by a coyote. Just as I began to think that Ono was gone forever, a neighbor described to me a cat who was showing up on her security camera in the middle of the night. From the description, I knew that it was Ono. I borrowed a humane trap from Marin Friends of Ferals and after thirteen nights and a couple of raccoons, I had Ono back. She had been on her own for 106 days. Tropical forest or temperate forest, it's all the same to my little tiger.

Ono Caught!

I don't mean to dismiss the threat posed by coyotes; the reports of cats gone missing and half-eaten carcasses discovered are real. It may well be that Ono will stay out one night and not be seen ever again, but Ono was born free, and she enjoys her freedom with all of its associated risks. Meanwhile, I treasure each day that I am privileged to enjoy with her. It is my hope that, despite being on the edge of the Golden Gate National Recreation Area and prime habitat for the coyotes, the scents of the more than a dozen dogs resident on the 000 block of Edwards Avenue mark it as territory unfriendly to coyotes. So far, so good.

Ono Enjoying the Great Outdoors... Under Supervision

Gangale's Dogs and Cats: Stories, Songs, and Images

Space Exploration in the United States: Status Report

Today I begin reviewing the proofs for "Space Exploration in the United States: A Documentary History." We are on track for a 30 November launch.

The Journey to Tranquility Base: A Topographic Voyage Through Time

NASA almost made landing the first humans on the Moon on John F. Kennedy’s deadline look easy. In fact, it was a deadline that was very nearly missed. The fiftieth anniversary of Apollo 11 is an appropriate time to review the scheduling history of that historic mission.

The slip chart is rarely used in project management, although the idea has been around for decades. It displays two dimensions of time: the passage of historical time (the past) along one axis, and projected time (the future) along the other axis. During nine years of managing satellite projects for the U.S. Air Force, including the Gambit and Hexagon programs and payloads for STS-4 and STS-39, I never once saw a slip chart. I didn’t even know that the concept existed until I found examples of them early in this century. However, In the mid-1970s I became interested in charting the changes over time in the scheduling of human space missions, and by 1978, at which time I was an aerospace engineering student at the University of Southern California, I invented the time map to graphically display this information; I do not claim to have been the first person to do so, although I believe I am the first to use this technique for detailed historical analysis. The Atlas of an Undiscovered Country is a project to map the entire history of human space exploration.


Figure 1: Saturn C-2

In August 1960, Apollo existed as a program which would send astronauts of a flyby of the Moon on the Saturn C-2 (see Figure 1) launch vehicle beginning in late 1968; as such, it may be said that the early Apollo program was analogous to the later Soviet L1 program (the Saturn C-2 was contemplated as consisting of a Saturn I first stage containing eight H-1 engines generating a total thrust of 1.7 million pounds, a second stage powered by four J-2 engines producing a total thrust of 800 thousand pounds, and a third stage containing six RL-10 engines generating a total thrust of 90 thousand pounds).(1) At this time, Apollo was more of a paper study than an actual development program, and any schedule had to assume some level of funding, yet the level of funding which the Eisenhower administration was willing to propose and which Congress was willing to support was highly uncertain, so it comes as no surprise that a January 1961 schedule showed that the first of two human flybys of the Moon as slipping to late 1969, while the first of four manned lunar orbital missions was slated for early 1970.(2) An actual Apollo landing on the Moon was contemplated as something which might be accomplished sometime later in the 1970s using some unspecified launch vehicle. Of course, the Kennedy administration’s May 1961 commitment to land a crew on the Moon by the end of the decade transformed the existing Apollo program, and for the first time that goal had a scheduled date associated with it. The second event which had a major impact on the scheduling history of the first human landing on the Moon was the spacecraft fire atop Apollo-Saturn 204 at Launch Complex 34 on 27 January 1967 which killed Apollo 1 astronauts Virgil Grissom, Edward White, and Roger Chaffee.


Figure 2: Time Map Overview

Figure 2 presents the complete scheduling history of the first human landing on the Moon, outlined in gold. To an engineer’s eye, the scheduling history up until the Apollo 1 accident calls to mind an oscillating signal whose amplitude and frequency are decreasing with time. To a project manager, this makes intuitive sense; one expects that as a project matures, known unknowns become knowns, and unknown unknowns become known unknowns, schedule estimates become more accurate and therefore more settled. The Apollo 1 accident caused a reset to the program, and again one sees the same phenomenon in the scheduling history: an oscillating signal whose amplitude and frequency are decreasing with time.


Figure 3: Time Map Detail - 1962

Figure 3 focuses on the period from December 1961 to June 1962. At the beginning of that period there were two mission modes under consideration: Earth Orbit Rendezvous (EOR), using two Saturn C-4 launch vehicles (see Figure 4), and Direct Ascent (DA), using a huge launch vehicle variously known as the Saturn C-8 or Nova (see Figure 5). The scheduling history of the first lunar landing via these mission modes, brief as it was, is highlighted in orange for EOR and in green for DA in Figure 3.


Figure 4: Saturn C-4


Figure 5: Nova

The Saturn C-4 design had four F-1 engines in the first stage, generating a total thrust of 6 million pounds, four J-2 engines in the second stage, generating a total thrust of 800 thousand pounds of thrust, and a single J-2 engine in the third stage, generating 200 thousand pounds of thrust.(3) The Saturn C-8 design had eight F-1 engines in the first stage, generating a total thrust of 12 million pounds, eight J-2 engines in the second stage, generating a total thrust of 1.6 million pounds(an alternative configuration had two M-2 engines producing a total of 2 million pounds of thrust), and two J-2 engines in the third stage producing a total of 400 thousand pounds of thrust (an alternative configuration had only a single J-2).(4) In both the DA and EOR modes, the Apollo Command and Service Modules (CSM) would have landed on the Moon (see Figure 6). The Service Propulsion System engine at the rear of the Apollo CSM was originally designed to launch the spacecraft off the surface of the Moon, although it was oversized for the lunar orbit insertion and Trans-Earth injection maneuvers it actually did perform during the Apollo lunar missions.


Figure 6: Apollo EOR and DA Landing Vehicle

For the EOR mission mode, an additional spacecraft was required. The Saturn C-4 did not have the payload capability to place the fully-loaded trans-lunar injection stage in low Earth orbit along with the lunar orbit insertion stage and the Apollo spacecraft, so a second, unmanned Saturn C-4 would launch a tanker spacecraft called the T-1, which would dock with the third stage (called the R-1) of the manned Saturn C-4 (see Figure 7). The liquid oxygen propellant in the T-1 would then be transferred to R-1, and from there the mission would proceed exactly as in the DA mode, landing the entire Apollo spacecraft on the Moon and the CSM launching from the surface to return to Earth. On 5 December 1961, little more than 6 months after President Kennedy committed the United States to landing a crew on the Moon by the end of the decade, NASA developed its first launch schedule showing the missions which would lead to the achievement of that goal.(5) NASA considered both the DA and EOR modes to be feasible and to support a human landing on the Moon in mid-1967, thus there was a comfortable 2.5-year schedule margin with respect to Kennedy’s announced goal.


Figure 7: Apollo T-1 Docked to R-1

Meanwhile, a new mission mode was attracting increased interest: Lunar Orbit Rendezvous (LOR). A great deal of mass could be saved by leaving the main spacecraft in lunar orbit while a small, light vehicle (the Lunar Excursion Module, later shortened to LM) carried two of the three astronauts to and from the surface. The LOR mission mode could be accomplished with a single Saturn C-5 launch vehicle. Later developed as the Saturn V, it contained five F-1 engines in the first stage, generating a total thrust of 7.5 million pounds, five J-2 engines in the second stage, generating a total thrust of 1 million pounds of thrust, and a single J-2 engine in the third stage. A launch schedule produced on 17 May 1962 projected the first landing to occur in November 1967.(6) Not represented in Figure 2 is a 25 May 1962 launch schedule in which Director of Manned Space Flight D. Brainerd Holmes predicted the LOR first landing to take place in August 1966.(7)

Schedules generated on different dates by different groups working at different offices are likely to be based on different assumptions. On 14 June 1962, Douglas Lord and Arthur Rudolf, assistant directors at the Office of Manned Space Flight, produced an apples-to-apples analysis of the three competing mission modes.(8) Their analysis, which was considerably more conservative than preceding schedule exercises, showed that the EOR first landing, now utilizing two Saturn C-5 launch vehicles, would not occur until January 1969. The DA mission mode came out even worse; because the more powerful Nova or Saturn C-8 launch vehicle would take longer to develop, could not support a first landing any earlier than February 1970. To them, LOR looked like the best bet, promising a first landing as early as October 1968 on Apollo Saturn 512. Shortly after the distribution of this analysis, NASA chose the LOR mission mode for the Apollo program.


Figure 8: Time Map Detail - 1963

Referring to Figure 8, on 15 October 1962, Holmes distributed a launch schedule showing the first landing as Apollo Saturn 509 (the ninth Saturn V flight), occurring in October 1967, a full year ahead of the conservative analysis produced by Lord and Rudolf (9). The scheduled launch date for AS-509 remained consistent through June 1963;(10-15) however, a launch schedule produced by Robert O. Pilland of the Manned Spacecraft Center (later Johnson Space Center) showed the first landing occurring on AS-510 (the tenth Saturn V flight) in March 1968,(16) and J. Thomas Markley’s 15 October 1963 flight schedule placed AS-510 in October 1968;(17) thus in only three months the first lunar handing goal had slipped an entire year. George E. Mueller’s 1 November 1963 memorandum confirmed this schedule slip.(18)


Figure 9: Time Map Detail - 1964

In 1964, NASA made up some of the lost schedule (see Figure 9). A 1 March flight schedule indicated that Apollo 507 would be the first “lunar mission;” although not explicitly stated, it is probable that this mission would have been a lunar orbital dress rehearsal for the first landing attempt on Apollo 508.(19) A mission summary later that month gave the launch date of Apollo 508 as July 1968,(20), as did the mission assignments document of 23 March.(21) By May, Kraft’s Schedule gave Apollo 505 as the first lunar mission; again, this is inferred to be a lunar orbital rehearsal for a first landing attempt on Apollo 506.(22) The 21 July 1964 mission assignments document indicated that Apollo 506 was slated for March 1968.(23) This date held steady throughout 1965 and 1966 (see Figures 10 and 11). It should be noted that in some of these documents, Saturn V missions were ambiguously labeled “lunar mission simulations and lunar missions,” with no specific indication of which mission would perform the first landing attempt, or indeed, what the specific goals and mission profiles of any of these flights might be; thus, determining for what the date of the first landing attempt might reasonably be estimated requires a judgment call based on the sequence of missions leading up to the first landing attempt which NASA defined later in the Apollo program.(24-30) With this caveat, it may be observed that the Apollo program had passed through its early years of schedule fluctuations and had settled into a firm schedule with a comfortable 21-month margin with respect to the end of the decade.


Figure 9: Time Map Detail - 1965


Figure 10: Time Map Detail - 1966


Figure 11: Time Map Detail - 1967


Figure 12: Time Map Detail - 1968

Of course, the Apollo 204 spacecraft fire through that firm schedule out the window (see Figure 12). In fact, the launch schedule had already begun to slip due to delays in the development of the Saturn V launch vehicle. Robert C. Seamans issued a document on 24 February 1967 which indicated that Apollo 506 and Apollo 507, which before the Apollo 204 accident had been slated for the third and fourth quarters of 1968, respectively, were to be either lunar mission simulations or lunar missions;(31) it may be reasonably speculated that Apollo 506 would have been a lunar orbital rehearsal for Apollo 507’s landing attempt. It is worth noting that a 4 February 1967 Soviet government decree outlined a schedule to land the first cosmonaut on the Moon in September 1968 (highlighted in yellow in Figure 12), although it was the opinion of Nikolai Petrovich Kamanin, commander of the cosmonaut detachment, that no lunar landing could occur until 1969.(32) On paper, the race for the Moon was now a dead heat.

George M. Low’s letter of 4 May 1967 pointed to the first landing attempt occurring on Apollo 505 in October 1968.(33) However, as the consequences of the Apollo 204 accident rippled through NASA, a new conservatism became increasingly evident. Mueller’s 1 November 1967 memorandum indicated that the lunar landing phase of the Apollo program would not begin until Apollo 509 in December 1969;(34) there was no longer any margin in the launch schedule to absorb further delays if the goal was to be achieved “before this decade is out.”

Figure 13: Time Map Detail - 1969

In the face of being up against this politically-driven deadline, NASA managers looked for ways to abbreviate the schedule and open up a margin in case the landing could not be achieved on the first attempt. The January 1968 mission assignments document defined the lunar mission phase, beginning with what was now designated Mission F (the lunar orbital rehearsal), as being assigned to Apollo 506 through Apollo 515.(35) According to the Apollo launch schedule, Apollo 507 (presumably Mission G, the first landing attempt) was scheduled for July 1969; however, this schedule was predicated on Mission D, the lunar mission simulation in low Earth orbit, occurring on Apollo 504 in December 1968 (highlighted in green in Figure 13), and the delivery of the Lunar Module for this mission was falling behind schedule. Despite the delay in the Saturn V development program and the year and a half consumed by the redesign of the Command Module in the aftermath of the Apollo 204 fire, it was the LM that ultimately turned out to be the long pole in the tent. Apollo 4 (Apollo 501) had performed Mission A-1 successfully on 9 November 1967, and two more unmanned Saturn V flights were contemplated before Mission D on Apollo 504. The first unmanned low Earth orbital LM test on Apollo 5 (Apollo 204, using the same launch vehicle atop which Grissom, White, and Chaffee had perished a year earlier) performed Mission B-1 successfully on 22 January 1968, and the deletion of a planned Mission B-2 was contemplated, but while this would save money, it would not affect the schedule for Mission D.(36) Apollo 6 (Apollo 502) performed Mission A-2 well enough on 4 April 1968 to cancel a third unmanned Saturn V test (Mission A-3) and assign Apollo 503 to Mission D (highlighted in purple in Figure 13), still scheduled for December 1968.(37) By August 1968, it became clear that LM-3 would not be ready in time for a December launch, and that an alternate mission had to be considered for AS-503. Launching only a CSM on a Saturn V on a low Earth orbital mission would be a needlessly expensive repeat of the Mission C, the first manned Apollo mission, that was planned for Apollo 7 launched on a smaller Saturn IB (AS-205). Deputy NASA Administrator Thomas O. Paine reported a consensus “to hold options open for December mission with range of alternatives from low earth orbit to the maximum capability of a lunar orbital mission,” but “the final decision to fly the ultimate mission must clearly be held until after Apollo 7 flight in October.”(38) Apollo 7 being an unqualified success, Apollo 8 became a CSM-only lunar orbital flight designated as Mission C-Prime (highlighted in green in Figure 13). Mission D was slipped to Apollo 9 (AS-504) in March 1969; however, Apollo 8’s early lunar orbital mission eliminated the need for Mission E (highlighted in orange), which was to have flown the complete CSM-LM package in an elliptical orbit ranging out to 5000 nautical miles. Swapping Mission E for Mission C-Prime allowed Mission F (Apollo 10, AS-505) to remain on schedule for May 1969, and likewise allowed Mission G (Apollo 11, AS-506) to remain on schedule for July 1969. If the Apollo 11 landing attempt was not achieved, Apollo 12 could make a second attempt before the end of 1969.

All referenced NASA documents are available from the NASA Technical Reports Server or the Johnson Space Center History Collection at the University of Houston-Clear Lake.

1. Encyclopedia Astronautica, “Saturn C-2,” http://www.astronautix.com/s/saturnc-2.html.
2. “Project Apollo,” 20 January 1961. HSI-16093.
3. Encyclopedia Astronautica, “Saturn C-4,” http://www.astronautix.com/s/saturnc-4.html.
4. Encyclopedia Astronautica, “Saturn C-8,” http://www.astronautix.com/s/saturnc-8.html.
5. Office of Manned Space Flight, “Long Range Plan, Part 1: Spacecraft and Flight Missions,” 5 December 1961. HSI-16961.
6. Hammock, David M., Manned Spacecraft Center, “Review of Flight Test and Development Plan,” 17 May 1962. HSI-17486.
7. Holmes, D. Brainerd, Office of Manned Space Flight, “The Manned Lunar Landing Program,” 25 May 1962. HSI-17512.
8. Lord, Douglas, and Arthur Rudolf, Office of Manned Space Flight, “Conservative Schedule Exercise for Manned Lunar Landing,” 14 June 1962. HSI-17586.
9. Holmes, D. Brainerd, Office of Manned Space Flight, “Manned Space Flight Program Launch Schedule for Apollo and Saturn Class Vehicles,” 15 October 1962. HSI-18134.
10. Frick, Charles W., Manned Spacecraft Center, “Designations for Apollo Missions,” 26 October 1962. HSI-18197.
11. Disher, John H., Office of Manned Space Flight, “Review of Apollo Quarterly Status Report No. 2,” 23 January 1963. HSI-18630.
12. Office of Manned Space Flight, “Preliminary Apollo Flight Mission Assignments,” 14 February 1963.
13. Manned Spacecraft Center, “Project Apollo Quarterly Status Report No. 3 for Period Ending March 31, 1963.”
14. Office of Manned Space Flight, “Apollo Flight Mission Assignments,” 9 April 1963. HSI-19002.
15. Manned Spacecraft Center, “Project Apollo Quarterly Status Report No. 3 for Period Ending 30 June 1963.”
16. Pilland, Robert O., Manned Spacecraft Center, “Apollo Flight Schedule,” 30 September 1963. HSI-20122.
17. Markley, J. Thomas, Manned Spacecraft Center, “Apollo Flight Schedule,” 15 October 1963. HSI-20263.
18. Mueller, George E., NASA Headquarters, “Revised Manned Space Flight Schedule,” 1 November 1963. HSI-20368
19. Kraft, Christopher C., Jr., “Integrated Flight Schedule,” 3 March 1963. HSI-21084.
20. “Flight Mission Summary,” 19 March 1964. HSI-137691.
21. Office of Manned Space Flight, “Apollo Flight Mission Assignments,” 23 March 1964.
22. Kraft, Christopher C., Jr., “Integrated Flight Schedules,” 28 May 1964. HSI-137843
23. Office of Manned Space Flight, “Apollo Flight Mission Assignments,” 21 July 1964. HSI-21919.
24. Phillips, Samuel C., NASA Headquarters, “Apollo Delivery and Launch Schedules,” 15 February 1965. HSI-23577.
25. Office of Manned Space Flight, “Apollo Flight Mission Assignments,” 19 February 1965. HSI-23619.
26. Phillips, Samuel C., NASA Headquarters, “Apollo Delivery and Launch Schedules,” 11 March 1965. HSI-23771.
27. Office of Manned Space Flight, “Apollo Flight Mission Assignments,” 10 September 1965. HSI-25314.
28. Office of Manned Space Flight, “Apollo Flight Mission Assignments,” July 1966. HSI-27705.
29. Office of Manned Space Flight, “Apollo Flight Mission Assignments,” November 1966. HSI-28564.
30. Shea, Joseph F., Apollo Spacecraft Program Office, “Revisions to Apollo Flight Program,” 16 November 1966. HSI-28474.
31. Seamans, Robert C., NASA Headquarters, “NASA Flight Schedule,” 24 February 1967. HSI-29227.
32. Encyclopedia Astronautica, “Lunar L3.” http://www.astronautix.com/l/lunarl3.html.
33. Low, George M., NASA Headquarters, “Apollo Schedules,” 4 May 1967. HSI-29790.
34. Mueller, George E., NASA Headquarters, “Apollo Flight Schedule,” 1 November 1967. HSI-13478.
35. Office of Manned Space Flight, “Apollo Flight Mission Assignments,” January 1968. HSI- 32599.
36. Finger, Harold B., NASA Headquarters, “Apollo Flight Schedule,” 19 March 1968. HSI-32882.
37. Finger, Harold B., NASA Headquarters, “Review of Proposed Change in Apollo Flight Schedule,” 24 April 1968. HSI-33227.
38. Paine, Thomas O., NASA Headquarters, cablegram to James E. Webb, 15 August 1968. HSI-34559.