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The center couch, including the crewman parachute and survival kit, could be folded out to a sleep position and stowed under either remaining couch. Allowance was made for the crewman to turn over.
Principal problems remaining were the difficulty of removing the center couch and providing the clearances needed for the couch positions specified for various phases of the lunar mission.
A study on the direct vision requirement for lunar landing showed that, to have a simultaneous direct view of the lunar landing point and the landing feet without changing the spacecraft configuration, a periscope with a large field of view integrated with a side window would be needed. A similar requirement on the general-purpose telescope could thus be eliminated, reducing the complexity of the telescope design.
Another study showed that, with an additional weight penalty of from five to ten pounds, an optical drift indicator for use after parachute deployment could easily be incorporated into the general-purpose telescope.
One 16-mm camera was also planned for the spacecraft. This camera would be positioned level with the commander's head and directed at the main display panel. It could be secured to the telescope for recording motion events in real time such as rendezvous, docking, launch and recovery of a lunar excursion module, and earth landing; it could be hand-held for extravehicular activity.
Among the items deleted from the command module (CM) were exercise and recreation equipment, personal parachutes and parachute containers located in the couches, individual survival kits, solar radiation garments, and eight-ball displays. A telescope, cameras and magazines considered scientific equipment, and a television monitor were deleted from the CM instrumentation system.
All sequencing was normal. The tower-jettison motor sent the escape tower into a proper ballistic trajectory. The drogue parachute deployed as programmed, followed by the pilot parachute and main parachutes. The test lasted 165.1 seconds. The postflight investigation disclosed only one significant problem: exhaust impingement that resulted in soot deposits on the CM.
MSC directed North American to proceed with the tower flap as its prime effort, and attempt to solve the stability problem at the earliest possible date. MSC's Engineering and Development Directorate resumed its study of both configurations, with an in-depth analysis of the canard system, in case the stability problem on the tower flap could not be solved by the end of the year.
On October 20 Horner told Low he had taken time to assure himself of the best possible information available before replying and offered background on the situation: "The design effort goes back to 1961 and testing began at the El Centro facility in 1962. There was continuous operation of the test group at El Centro until 1966 when the completion of the Block II testing program dictated the closeout of our operation there. In our total activity, we have had a peak of 350 personnel assigned to the Apollo, with 20 of that number located at El Centro during the most active portion of the test program. When it was finally determined that the increased weight capability redesign was necessary for mission success, the program nucleus had been reduced to 30 personnel and the established schedule for the system re-design, test and fabrication requires a build-up to 250. . . . The schedule has also dictated the adoption of such procedures as concurrent inspection by the inspectors of Northrop, North American and NASA, a procedure which, I am sure, is efficient from a program point of view but is inherently risky in terms of the wide dissemination of knowledge concerning every human mistake. This is significant only from the point of view of the natural human failing to be more willing to share the responsibility for error than for success. . . . We do not intend in any way to share responsibility for these errors and expect to eliminate the potential for their recurrence. We have established standards of quality for this program that are stringent and uncompromising. . . . Even though the technical and schedule challenge is substantial, we are confident that by the time qualification testing is scheduled to start during the first week of December 1967 we will have a flawless operation. . . ."
Main objectives of the mission were to demonstrate the structural and thermal integrity of the space vehicle and to verify adequacy of the Block II heatshield design for entry at lunar return conditions. These objectives were accomplished.
The S-IC stage cutoff occurred 2 minutes 30 seconds into the flight at an altitude of about 63 kilometers. The S-II stage ignition occurred at 2 minutes 32 seconds and the burn lasted 6 minutes 7 seconds, followed by the S-IVB stage ignition and burn of 2 minutes 25 seconds. This series of launch vehicle operations placed the S-IVB and spacecraft combination in an earth parking orbit with an apogee of about 187 kilometers and a perigee of 182 kilometers. After two orbits, which required about three hours, the S-IVB stage was reignited to place the spacecraft in a simulated lunar trajectory. This burn lasted five minutes. Some 10 minutes after completion of the S-IVB burn, the spacecraft and S-IVB stage were separated, and less than 2 minutes later the service propulsion subsystem was fired to raise the apogee. The spacecraft was placed in an attitude with the thickest side of the CM heatshield away from the solar vector. During this four-and-one-half-hour cold-soak period, the spacecraft coasted to its highest apogee - 18,256.3 kilometers. A 70 mm still camera photographed the earth's surface every 10.6 seconds, taking 715 good-quality, high-resolution pictures.
About 8 hours 11 minutes after liftoff the service propulsion system was again ignited to increase the spacecraft inertial velocity and to simulate entry from a translunar mission. This burn lasted four and one half minutes. The planned entry velocity was 10.61 kilometers per second, while the actual velocity achieved was 10.70.
Recovery time of 2 hours 28 minutes was longer than anticipated, with the cause listed as sea conditions - 2.4-meter swells.
On February 29, Myers assured Kleinknecht that North American had proceeded with the BP-19A task in advance of NASA full coverage. Initial partial coverage was issued to North American on January 5, 1968. On March 14, in a letter of commendation, Kleinknecht thanked Myers for the attention given the BP-19A effort that made a March 15 completion by Western Ways possible. On May 27, W. H. Gray, RASPO Manager, wrote another letter of commendation thanking North American for completing BP-19A in time for a drop test in May 1968.
Liftoff at 7:00 a.m. EST was normal but, during the first-stage (S-IC) boost phase, oscillations and abrupt measurement changes were observed. During the second-stage (S-II) boost phase, two of the J-2 engines shut down early and the remaining three were extended approximately one minute to compensate. The third stage (S-IVB) firing was also longer than planned and at termination of thrust the orbit was 177.7 x 362.9 kilometers rather than the 160.9-kilometer near-circular orbit planned. The attempt to reignite the S-IVB engine for the translunar injection was unsuccessful. Reentry speed was 10 kilometers per second rather than the planned 11.1, and the spacecraft landed 90.7 kilometers uprange of the targeted landing point.
The most significant spacecraft anomaly occurred at about 2 minutes 13 seconds after liftoff, when abrupt changes were indicated by strain, vibration, and acceleration measurements in the S-IVB, instrument unit, adapter, lunar module test article, and CSM. Apparently oscillations induced by the launch vehicle exceeded the spacecraft design criteria.
The second-stage (S-II) burn was normal until about 4 minutes 38 seconds after liftoff; then difficulties were recorded. Engine 2 cutoff was recorded about 6 minutes 53 seconds into the flight and engine 3 cutoff less than 3 seconds later. The remaining second-stage engines shut down at 9 minutes 36 seconds - 58 seconds later than planned.
The S-IVB engine during its first burn, which was normal, operated 29 seconds longer than programmed. After two revolutions in a parking orbit, during which the systems were checked, operational tests performed, and several attitude maneuvers made, preparations were completed for the S-IVB engine restart. The firing was scheduled to occur on the Cape Kennedy pass at the end of the second revolution, but could not be accomplished. A ground command was sent to the CSM to carry out a planned alternate mission, and the CSM separated from the S-IVB stage.
A service propulsion system (SPS) engine firing sequence resulted in a 442-second burn and an accompanying free-return orbit of 22,259.1 x 33.3 kilometers. Since the SPS was used to attain the desired high apogee, there was insufficient propellant left to gain the high-velocity increase desired for the entry. For this reason, a complete firing sequence was performed except that the thrust was inhibited.
Parachute deployment was normal and the spacecraft landed about 9 hours 50 minutes after liftoff, in the mid-Pacific, 90.7 kilometers uprange from the predicted landing area (27.40 N 157.59 W). A normal retrieval was made by the U.S.S. Okinawa, with waves of 2.1 to 2.4 meters.
The spacecraft was in good condition, including the unified crew hatch, flown for the first time. Charring of the thermal protection was about the same as that experienced on the Apollo 4 spacecraft (CM 017).
Of the five primary objectives, three - demonstrating separation of launch vehicle stages, performance of the emergency detection system (EDS) in a close-loop mode, and mission support facilities and operations - were achieved. Only partially achieved were the objectives of confirming structure and thermal integrity, compatibility of launch vehicle and spacecraft, and launch loads and dynamic characteristics; and of verifying operation of launch vehicle propulsion, guidance and control, and electrical systems. Apollo 6, therefore, was officially judged in December as "not a success in accordance with . . . NASA mission objectives."