When AS-503 - the third Saturn V - was erected on 20 December 1967, it had been scheduled for the unmanned launch of a boilerplate Apollo in May 1968. By late January the launch team had stacked the remaining stages on mobile launcher 1. Despite the success of Apollo 4, the flight hardware still carried considerable research instrumentation. As the Apollo 6 mission neared, KSC hastened to complete the integrated testing of AS-503 in the assembly building. Admiral B. O. Middleton, KSC's Apollo Program Manager, had informed Phillips that, if Apollo 6 failed and another unmanned Saturn V were needed, AS-503 could roll out to the pad within ten days. Final preparations for the move were held pending analysis of the Apollo 6 flight test data and the decision whether AS-503 would be manned or not. KSC's chance to demonstrate the relative speed and economy of the mobile concept disappeared in the ripples created by pogo.43
Despite the disappointment of the Apollo 6 flight, NASA was reasonably confident in its analysis of the Saturn V problems. On 23 April, Mueller recommended a revised Apollo schedule to Administrator Webb, including provisions to man Apollo 8. The next day in a press briefing at NASA Headquarters, Phillips stated that, in spite of the problems, Apollo 6 had been a safe mission. He supported Mueller's recommendation by advocating that NASA prepare for a manned flight late in 1968 on the third Saturn V with the option to revert to an unmanned mission if corrections did not meet the requirements felt necessary to ensure crew safety.44
The revised schedule was approved by the Administrator on 26 April in a note endorsing the planning, design, fabrication, development, and proof-testing necessary for a manned AS-503. The Administrator did not, however, authorize such a mission at that time. The decision would come later and would be subject to several restrictions. Specifically, manning the mission was contingent upon the resolution of the Apollo 6 problems and the results of the Apollo 7 (AS-205) flight.45
KSC work schedules reflected the ambivalence of the Apollo 8 mission. If the vehicle was to have the unmanned boilerplate aboard with a lunar module test vehicle, the launch date would be 10 July. Allowances for a slippage to 15 October were built in for testing the fixes. If 503 was to be manned, it would fly CSM-103 and LM-3 no earlier than 20 November. As the manned alternative took precedence, KSC moved quickly to meet its demands. One requirement was an additional cryogenic proof pressure test for the S-II stage at the Mississippi Test Facility. By 30 April the launch team had taken the Saturn V apart and put the S-II aboard a barge. At Mississippi Test Facility the second stage, in addition to cryogenic testing, underwent modifications to the spark igniters. The J-2 engine of the third stage received the same modifications at KSC. Phillips hoped to increase the chances of meeting a manned launch in November by spreading out the necessary modifications among the various centers.46
In early May a problem in the first stage added to KSC's hardware difficulties. On 7 May, during a leak check on the turbopump of an engine on the first stage of AS-503, about 0.6 liter leaked from the main fuel seal in a period of 10 minutes. After evaluation, a decision to change the engine was made. The new engine was shipped on 20 May and arrived at KSC the following day. It took the remainder of the month to install and check out the replacement.47
By the middle of June, all approved modifications to the stages and the ground support equipment at KSC were in work. Several expected modifications, however, had not yet been approved or received. Consequently, KSC officials had some doubts that the planning schedule could be maintained. One anticipated change was the modification to suppress pogo in the first stage. Although KSC had not received approval for the modification, the work had to be done and it would probably delay the internal power tests on the stage. On 13 June the RCA computers in firing room 1 and in mobile launcher 1 malfunctioned. They, too, were undergoing modifications. The troubles were isolated to two printed-circuit cards and an open circuit in the mobile launcher's computer.48
After two Saturn V missions, operations at LC-39 were still not what might have been hoped. As one participant later observed about the period after Apollo 6: "Few working here on a daily basis really thought we were going to be able to make it by 1969. Everything took too long." This observation was directed largely at the Apollo spacecraft.49
The same mood was evident at a closed meeting held at Grumman Aircraft and Engineering Corporation in July 1968. At that time, Phillips noted that "the lunar landing next year is within our grasp, but we don't have a hold of it because of the [contractors' disregard of planned delivery dates]." Mueller noted that "the rate of changes in the [lunar module] was three times that of the Apollo command module, whose rate of changes, in turn, was four times that of the Saturn V rocket. . . . The changes placed added burden on [KSC] technicians who should be concentrating on launching operations, not on vehicle modifications."50
By the summer of 1968, problems at Apollo factories were stretching KSC's workload beyond its capabilities. Furthermore, the preparation of lunar module 3 for the Apollo 8 mission was only the second mission for the Grumman team, and its inexperience showed. Charles Mathews, former Gemini program director, expressed concern about launch operations after a two-day visit to KSC. "The amount of rework [on LM-3] necessary at KSC was more than should be required in Florida." While acknowledging the overload, Mathews criticized Grumman engineers for reacting too slowly. They in turn complained about a lack of support from Bethpage. Mathews believed that neither North American nor Grumman had sufficient knowledge of manufacturing requirements. He recommended that both contractors appoint spacecraft managers to direct operations from factory to launch - "someone with as much authority within the Cape organization as he has at the factory."51
In mid-July Debus addressed the problem of KSC's handling three Apollo-Saturn V missions concurrently. A letter to Mueller noted an apparent misunderstanding between headquarters staff members and KSC. Debus pointed out that, prior to the issuance of Apollo Program Directive 4H in November 1967, no schedule had shown more than two Saturn V vehicles at KSC simultaneously. Since then, he continued, discussions with Phillips had indicated that KSC should be able to process three vehicles concurrently. Funding constraints, however, had hampered efforts to enlarge the stage contractors' operations team.52
In a reply to Debus the following month, Phillips stated that the schedule was not, in fact, being met by KSC. To carry out the flights that were programed for the next year, KSC had to be able to process three vehicles concurrently. Phillips emphasized the efficient use of available resources and authorized KSC to provide crews for some phases of work on three vehicles simultaneously.53