In discussing the advanced manned spacecraft program at NASA Centers, Maxime A. Faget of STG detailed the guidelines for aborted missions and landing:
The Martin Company presented the first technical review of its Apollo feasibility study to STG officials in Baltimore, Md. At the suggestion of STG, Martin agreed to reorient the study in several areas: putting more emphasis on lunar orbits, putting man in the system, and considering landing and recovery in the initial design of the spacecraft.
Representatives of STG visited The Martin Company in Baltimore, Md., to review the progress of the Apollo feasibility study contract. Discussions on preliminary design of the spacecraft, human factors, propulsion, power supplies, guidance and control, structures, and landing and recovery were held with members of the Martin staff.
An Apollo Egress Working Group, consisting of personnel from Marshall Space Flight Center, Launch Operations Directorate, and Atlantic Missile Range, was formed on November 2. Meetings on that date and on November 6 resulted in publication of a seven-page document, "Apollo Egress Criteria." The Group established ground rules, operations and control procedures criteria, and space vehicle design criteria and provided requirements for implementation of emergency egress system.
The organizational elements and staffing for the MSC Apollo Spacecraft Project Office was announced:
Robert O. Piland, Deputy Project Manager
William F. Rector, Special Assistant
Calvin H. Perrine, Flight Technology
Lee N. McMillion, Crew Systems
David L. Winterhalter, Sr., Power Systems
Wallace D. Graves, Mechanical Systems
Milton C. Kingsley, Electrical Systems
(Vacant), Ground Support Equipment
Jack Barnard, Apollo Office at MIT
(Vacant), Reliability and Quality Control
Emory F. Harris, Operations Requirements
Robert P. Smith, Launch Vehicle Integration
Owen G. Morris, Mission Engineering
Marion R. Franklin, Ground Operational Support Systems
Alan B. Kehlet, Engineering
Alan B. Kehlet, Acting Manager, Quality Control and Engineering
Herbert R. Ash, Acting Manager, Business Administration
A meeting to review the lunar orbit rendezvous (LOR) technique as a possible mission mode for Project Apollo was held at NASA Headquarters. Representatives from various NASA offices attended: Joseph F. Shea, Eldon W. Hall, William A. Lee, Douglas R. Lord, James E. O'Neill, James Turnock, Richard J. Hayes, Richard C. Henry, and Melvyn Savage of NASA Headquarters; Friedrich O. Vonbun of Goddard Space Flight Center (GSFC); Harris M. Schurmeier of Jet Propulsion Laboratory; Arthur V. Zimmeman of Lewis Research Center; Jack Funk, Charles W. Mathews, Owen E. Maynard, and William F. Rector of MSC; Paul J. DeFries, Ernst D. Geissler, and Helmut J. Horn of Marshall Space Flight Center (MSFC); Clinton E. Brown, John C. Houbolt, and William H. Michael, Jr., of Langley Research Center; and Merrill H. Mead of Ames Research Center. Each phase of the LOR mission was discussed separately.
The launch vehicle required was a single Saturn C-5, consisting of the S-IC, S-II, and S-IVB stages. To provide a maximum launch window, a low earth parking orbit was recommended. For greater reliability, the two-stage-to-orbit technique was recommended rather than requiring reignition of the S-IVB to escape from parking orbit.
The current concepts of the Apollo command and service modules would not be altered. The lunar excursion vehicle (LEV), under intensive study in 1961, would be aft of the service module and in front of the S-IVB stage. For crew safety, an escape tower would be used during launch. Access to the LEV would be provided while the entire vehicle was on the launch pad.
Both Apollo and Saturn guidance and control systems would be operating during the launch phase. The Saturn guidance and control system in the S-IVB would be "primary" for injection into the earth parking orbit and from earth orbit to escape. Provisions for takeover of the Saturn guidance and control system should be provided in the command module. Ground tracking was necessary during launch and establishment of the parking orbit, MSFC and GSFC would study the altitude and type of low earth orbit.
The LEV would be moved in front of the command module "early" in the translunar trajectory. After the S-IVB was staged off the spacecraft following injection into the translunar trajectory, the service module would be used for midcourse corrections. Current plans were for five such corrections. If possible, a symmetric configuration along the vertical center line of the vehicle would be considered for the LEV. Ingress to the LEV from the command module should be possible during the translunar phase. The LEV would have a pressurized cabin capability during the translunar phase. A "hard dock" mechanism was considered, possibly using the support structure needed for the launch escape tower. The mechanism for relocation of the LEV to the top of the command module required further study. Two possibilities were discussed: mechanical linkage and rotating the command module by use of the attitude control system. The S-IVB could be used to stabilize the LEV during this maneuver.
The service module propulsion would be used to decelerate the spacecraft into a lunar orbit. Selection of the altitude and type of lunar orbit needed more study, although a 100-nautical-mile orbit seemed desirable for abort considerations.
The LEV would have a "point" landing (±½ mile) capability. The landing site, selected before liftoff, would previously have been examined by unmanned instrumented spacecraft. It was agreed that the LEV would have redundant guidance and control capability for each phase of the lunar maneuvers. Two types of LEV guidance and control systems were recommended for further analysis. These were an automatic system employing an inertial platform plus radio aids and a manually controlled system which could be used if the automatic system failed or as a primary system.
The service module would provide the prime propulsion for establishing the entire spacecraft in lunar orbit and for escape from the lunar orbit to earth trajectory. The LEV propulsion system was discussed and the general consensus was that this area would require further study. It was agreed that the propulsion system should have a hover capability near the lunar surface but that this requirement also needed more study.
It was recommended that two men be in the LEV, which would descend to the lunar surface, and that both men should be able to leave the LEV at the same time. It was agreed that the LEV should have a pressurized cabin which would have the capability for one week's operation, even though a normal LOR mission would be 24 hours. The question of lunar stay time was discussed and it was agreed that Langley should continue to analyze the situation. Requirements for sterilization procedures were discussed and referred for further study. The time for lunar landing was not resolved.
In the discussion of rendezvous requirements, it was agreed that two systems be studied, one automatic and one providing for a degree of manual capability. A line of sight between the LEV and the orbiting spacecraft should exist before lunar takeoff. A question about hard-docking or soft-docking technique brought up the possibility of keeping the LEV attached to the spacecraft during the transearth phase. This procedure would provide some command module subsystem redundancy.
Direct link communications from earth to the LEV and from earth to the spacecraft, except when it was in the shadow of the moon, was recommended. Voice communications should be provided from the earth to the lunar surface and the possibility of television coverage would be considered.
A number of problems associated with the proposed mission plan were outlined for NASA Center investigation. Work on most of the problems was already under way and the needed information was expected to be compiled in about one month.
[This meeting, like the one held February 13-15, was part of a continuing effort to select the lunar mission mode].
Milton W. Rosen, NASA Office of Manned Space Flight Director of Launch Vehicles and Propulsion, recommended that the S-IVB stage be designed specifically as the third stage of the Saturn C-5 and that the C-5 be designed specifically for the manned lunar landing using the lunar orbit rendezvous technique. The S-IVB stage would inject the spacecraft into a parking orbit and would be restarted in space to place the lunar mission payload into a translunar trajectory. Rosen also recommended that the S- IVB stage be used as a flight test vehicle to exercise the command module (CM), service module (SM), and lunar excursion module (LEM) [previously referred to as the lunar excursion vehicle (LEV)] in earth orbit missions. The Saturn C-1 vehicle, in combination with the CM, SM, LEM, and S-IVB stage, would be used on the most realistic mission simulation possible. This combination would also permit the most nearly complete operational mating of the CM, SM, LEM, and S-IVB prior to actual mission flight.
NAA studies resulted in significant changes in the command module environmental control system (ECS).
Wernher von Braun, Director, Marshall Space Flight Center, recommended to the NASA Office of Manned Space Flight that the lunar orbit rendezvous mode be adopted for the lunar landing mission. He also recommended the development of an unmanned, fully automatic, one-way Saturn C-5 logistics vehicle in support of the lunar expedition; the acceleration of the Saturn C-1B program; the development of high-energy propulsion systems as a backup for the service module and possibly the lunar excursion module; and further development of the F-1 and J-2 engines to increase thrust or specific impulse.
NAA was directed by the Apollo Spacecraft Project Office at the monthly design review meeting to design an earth landing system for a passive touchdown mode to include the command module cant angle limited to about five degrees and favoring offset center of gravity, no roll orientation control, no deployable heatshield, and depressurization of the reaction control system propellant prior to impact. At the same meeting, NAA was requested to use a single "kicker" rocket and a passive thrust-vector-control system for the spacecraft launch escape system.
The first Apollo boilerplate command module, BP-25, was delivered to MSC for water recovery and handling tests. Flotation, water stability, and towing tests were conducted with good results. J. Thomas Markley of MSC described all spacecraft structural tests thus far as "successful."
An NAA study on the shift of the command module center of gravity during reentry proposed moving the crew and couches about ten inches toward the aft equipment bay and then repositioning them for landing impact.
A review of body angles used for the current couch geometry disclosed that the thigh-to-torso angle could be closed sufficiently for a brief period during reentry to shorten the overall couch length by the required travel along the Z-Z axis. The more acute angle was desirable for high g conditions. This change in the couch adjustment range, as well as a revision in the lower leg angle to gain structure clearance, would necessitate considerable couch redesign.
Elimination of the requirement for personal parachutes nullified consideration of a command module (CM) blowout emergency escape hatch. A set of quick-acting latches for the inward-opening crew hatch would be needed, however, to provide a means of egress following a forced landing. The latches would be operable from outside as well as inside the pressure vessel. Outside hardware for securing the ablative panel over the crew door would be required as well as a method of releasing the panel from inside the CM.
NAA completed a study of reentry temperatures. Without additional cooling, space suit inlet temperatures were expected to increase from 50 degrees F at 100,000 feet to 90 degrees F at spacecraft parachute deployment. The average heat of the command module inner wall was predicted not to exceed 75 degrees F at parachute deployment and 95 degrees F on landing, but then to rise to nearly 150 degrees F.
North American made a number of changes in the layout of the CM:
North American reported several problems involving the CM's aerodynamic characteristics; their analysis of CM dynamics verified that the spacecraft could - and on one occasion did - descend in an apex-forward attitude. The CM's landing speed then exceeded the capacity of the drogue parachutes to reorient the vehicle; also, in this attitude, the apex cover could not be jettisoned under all conditions. During low-altitude aborts, North American went on, the drogue parachutes produced unfavorable conditions for main parachute deployment.
Northrop Corporation's Ventura Division, prime contractor for the development of sea-markers to indicate the location of the spacecraft after a water landing, suggested three possible approaches:
MSC Flight Operations Division examined the operational factors involved in Apollo water and land landings. Analysis of some of the problems leading to a preference for water landing disclosed that:
The Mission Analysis Branch (MAB) of MSC's Flight Operations Division cited the principal disadvantages of the land recovery mode for Apollo missions. Of primary concern was the possibility of landing in an unplanned area and the concomitant dangers involved. For water recovery, the main disadvantages were the establishment of suitable landing areas in the southern hemisphere and the apex-down flotation problem. MAB believed no insurmountable obstacles existed for either approach.
North American simplified the CM water management system by separating it from the freon system. A 4.5- kilogram (10-pound) freon tank was installed in the left-hand equipment bay. Waste water formed during prelaunch and boost, previously ejected overboard, could now be used as an emergency coolant. The storage capacity of the potable water tank was reduced from 29 to 16 kilograms (64 to 36 pounds) and the tank was moved to the lower equipment bay to protect it from potential damage during landing. These and other minor changes caused a reduction in CM weight and an increase in the reliability of the CM's water management system.
At ASPO's request, Wayne E. Koons of the Flight Operations Division visited North American to discuss several features of spacecraft landing and recovery procedures. Koon's objective, in short, was to recommend a solution when ASPO and the contractor disagreed on specific points, and to suggest alternate courses when the two organizations agreed. A question had arisen about a recovery hoisting loop. Neither group wanted one, as its installation added weight and caused design changes. In another area, North American wanted to do an elaborate study of the flotation characteristics of the CM. Koons recommended to ASPO that a full-scale model of the CM be tested in an open-sea environment.
There were a number of other cases wherein North American and ASPO agreed on procedures which simply required formal statements of what would be done. Examples of these were:
At El Centro, Calif., Northrop Ventura conducted the first of a series of qualification tests for the Apollo earth landing system (ELS). The test article, CM boilerplate 3, was dropped from a specially modified Air Force C-133. The test was entirely successful. The ELS's three main parachutes reduced the spacecraft's rate of descent to about 9.1 meters (30 feet) per second at impact, within acceptable limits.
The Operational Evaluation and Test Branch of MSC's Flight Operations Division considered three methods of providing a recovery hoisting loop on the CM: loop separate from the spacecraft and attached after landing, use of the existing parachute bridle, and loop installed as part of the CM equipment similar to Mercury and Gemini. Studies showed that the third method was preferable.
The Mission Analysis Branch (MAB) of MSC's Flight Operations Division studied the phenomenon of a spacecraft's "skip" when reentering the earth's atmosphere from lunar trajectories and how that skip relates to landing accuracies. When an Apollo CM encounters the earth's atmosphere (this study used 91,440 meters [300,000 feet] as the practical altitude), the vehicle bounces or "skips" back above the atmosphere. From this point, the spacecraft follows a ballistic trajectory until it re-encounters the atmosphere. During this skip portion of reentry, there is no control of the vehicle's flight trajectory. The length of this skip is, therefore, determined by the angle and speed at the start of this ballistic trajectory. The distance of the skip in turn determines the spacecraft's landing area. Variations in both speed and angle at the start of the skip thus are directly related to landing accuracy, but the effect of these variations is felt much more in shallow than in steep trajectories. In light of these factors, MAB recommended that, for Apollo flights, the skip phase of reentry be made at the steepest practicable angle consistent with maximum allowable acceleration forces.
MSC Flight Operations Division (FOD) recommended a series of water impact tests to establish confidence in the CM's recovery systems under a variety of operating conditions. FOD suggested several air drops with water landings under various test conditions. Among these were release of the main parachutes at impact, deployment of the postlanding antennas, actuation of the mechanical location aids, and activation of the recovery radio equipment.
MSC made several changes in the CM's landing requirements. Impact attenuation would be passive, except for that afforded by the crew couches and the suspension system. The spacecraft would be suspended from the landing parachutes in a pitch attitude that imposed minimum accelerations on the crew. A crushable structure to absorb landing shock was required in the aft equipment bay area.
A joint North American-MSC meeting reviewed the tower flap versus canard concept for the earth landing system (ELS). During a low-altitude abort, MSC thought, the ELS could be deployed apex forward with a very high probability of mission success by using the tower flap configuration. The parachute system proposed for this mode would be very reliable, even though this was not the most desirable position for deploying parachutes. Dynamic stability of the tower flap configuration during high- altitude aborts required further wind tunnel testing at Ames Research Center. Two basic unknowns in the canard system were deployment reliability, and the probability of the crew's being able to establish the flight direction and trim the CM within its stability limits for a safe reentry. Design areas to be resolved were a simple deployment scheme and a spacecraft system that would give the crew a direction reference.
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.
The System Engineering Division (SED) examined the feasibility of performing an unmanned earth orbital mission without the guidance and navigation system. SED concluded that the stabilization and control system could be used as an attitude reference for one to two orbits and would have accuracies at retrofire suitable for recovery. The number of orbits depended upon the number of maneuvers performed by the vehicle, since the gyros tended to drift.
At a NASA-North American Technical Management Meeting at Downey, Calif., North American recommended that Apollo earth landings be primarily on water. On the basis of analytical studies and impact tests, the contractor had determined that "land impact problems are so severe that they require abandoning this mode as a primary landing mode." In these landings, North American had advised, it was highly probable that the spacecraft's impact limits would be surpassed. In fact, even in water landings "there may be impact damage which would result in leakage of the capsule." (ASPO Manager Joseph F. Shea, at this meeting, "stated that MSC concurs that land impact problems have not been solved, and that planning to utilize water impact is satisfactory."
Three days later, Shea reported to the MSC Senior Staff that Apollo landings would be primarily on water. The only exceptions, he said, would be pad aborts and emergency landings. With this question of "wet" versus "dry" landing modes settled, Christopher C. Kraft, Jr., Assistant Director for Flight Operations, brought up the unpleasant problem of the CM's having two stable attitudes while afloat - and especially the apex-down one. This upside-down attitude, Kraft emphasized, submerged the vehicle's recovery antennas and posed a very real possibility of flooding in rough seas. Shea countered that these problems could be "put to bed" by using some type of inflatable device to upright the spacecraft.
In response to MSC's new criteria for the landing gear of the LEM, Grumman representatives met with Center officials in Houston to revise the design. Grumman had formulated a concept for a 419-cm (165-in) radius, cantilever-type configuration, In analyzing its performance, Grumman and Structures and Mechanics Division (SMD) engineers, working separately, had reached the same conclusion: namely, that it did not provide sufficient stability nor did it absorb enough of the landing impact. Both parties to this meeting agreed that the gear's performance could be improved by redesigning the foot pads and beefing up the gear struts. Grumman was modifying other parts of the spacecraft's undercarriage accordingly.
At the same time, Grumman advised MSC that it considered impractical a contrivance to simulate lunar gravity in the drop program for test Mockup 5. Grumman put forth another idea: use a full-sized LEM, the company said, but one weighing only one-sixth as much as a flight-ready vehicle. SMD officials were evaluating this latest idea, while they were reviewing the entire TM-5 program.
To determine flotation characteristics of the spacecraft, the Stevens Institute of Technology began a testing program using one-tenth scale models of the CM. Researchers found that the sequence in which the uprighting bags were deployed was equally critical in both a calm sea and in various wave conditions; improper deployment caused the vehicle to assume an apex-down position. These trials disproved predictions that wave action would upright the spacecraft from this attitude.
Further testing during the following month reinforced these findings. But because sequential deployment would degrade reliability of the system, North American held that the bags must upright the spacecraft irrespective of the order of their inflation. Stevens' investigators would continue their program, examining the CM's characteristics under a variety of weight and center of gravity conditions.
North American proposed an idea for increasing the CM's land landing capability. This could be done, the company asserted, by raising the water impact limits (thus exceeding normal tolerances) and stiffening the shock struts. Presently, the spacecraft was incapable of a land landing within established requirements (i.e., in a 46-km [25-nm] wind). While even approximate figures were not available, the maximum wind velocity in which the CM could land - without exceeding crew tolerances - was probably between 19 and 28 km (10 and 15 nm) per hr. (No precise data on land and water landings would be available until after the drop tests of boilerplate 28 late in the year.)
Personnel of the ASPO Crew Integration Branch, however, were pessimistic about the North American scheme. They doubted that shock attenuation could be readily increased, nor did they see as likely any relaxation of crew tolerances. Further, the probability of a land landing introduced tighter constraints on wind conditions at the launch site. As they viewed it, the only feasible way to improve the spacecraft's ground capability was through some mechanism that would further absorb the landing impact.
During a pad abort, propellants from the CM's reaction control system (RCS) would be dumped overboard. Structures and Mechanics Division (SMD) therefore established a test program to evaluate possible deleterious effects on the strength of the earth landing system's nylon components. SMD engineers would expose test specimens to RCS fuel (monomethyl hydrazine) and oxidizer (nitrogen tetroxide). This testing series would encompass a number of variables: the length of exposure; the time period between that exposure and the strength test; the concentration of propellant; and the rate and direction of the air flow. Testing was completed near the end of the month. SMD reported that "no significant degradation was produced by any of the test exposure conditions."
On the basis of current systems reliabilities and the design reference mission, North American estimated at one in a hundred the possibility that returning Apollo crewmen would land on solid ground rather than on water. The contractor used this estimate in formulating test programs for boilerplate 28 and spacecraft 002A and 007.
Portable life support systems (PLSS) stowed against the aft bulkhead in the CM would prevent the crew couch from stroking fully. This condition would be aggravated if, at impact, the bulkhead was forced inward. North American spokesmen maintained that, in a water landing, the bulkhead would give only slightly and that the couch struts would not compress to their limits. They argued, therefore, that this condition would be of concern only in a land landing. On the contrary, said MSC. Center officials were adamant that any interference was absolutely unacceptable: it would lessen the attenuation capability of the couch (thereby jeopardizing crew safety); possibly, the bulkhead might even be ruptured (with obviously disastrous results). Because of this problem - and because the capability for extravehicular transfer from the CM to the LEM was required - MSC invited representatives from the three contractors involved to meet in Houston to deal with the question of PLSS stowage.
Developmental testing began on a new landing device for the CM, one using rockets (mounted on the heatshield) that would be ignited immediately before impact. The current method for ensuring the integrity of the spacecraft during a landing in rough water involved strengthening of the aft structure. The new concept, should it prove practicable, would offer a twofold advantage: first, it would lighten the CM considerably; second, it would provide an improved emergency landing capability.
William A. Lee, ASPO Assistant Manager, asked Systems Engineering Division to study the feasibility of an abbreviated mission, especially during the initial Apollo flights. Because of the uncertainties involved in landing, Lee emphasized, the first LEMs should have the greatest possible reserves. This could be accomplished, he suggested, by shortening stay time; removing surplus batteries and consumables; and reducing the scientific equipment. Theoretically, this would enable the LEM pilot to hover over the landing site for an additional minute; also, it would increase the velocity budgets both of the LEM's ascent stage and of the CSM. He asked that the spacecraft's specifications be changed to fly a shorter mission:
The following definitions were specified for use in evaluating design reliability, for design tradeoff studies, and in appropriate Interface Control Documentation:
NASA launched Apollo mission PA-2, a test of the launch escape system (LES) simulating a pad abort at WSMR. All test objectives were met. The escape rocket lifted the spacecraft (boilerplate 23A) more than 1,524 m (5,000 ft) above the pad. The earth landing system functioned normally, lowering the vehicle back to earth. This flight was similar to the first pad abort test on November 7, 1963, except for the addition of canards to the LES (to orient the spacecraft blunt end forward after engine burnout) and a boost protective cover on the CM. PA-2 was the fifth of six scheduled flights to prove out the LES.
North American recommended to MSC that, for the time being, the present method for landing the CM (i.e., a passive water landing) be maintained. However, on the basis of a recent feasibility study, the contractor urged that a rocket landing system be developed for possible use later on. North American said that such a system would improve mission reliability through the increase in impact capability on both land and water.
ASPO Manager Joseph F. Shea informed LEM Subsystems Managers that recent LEM schedule changes and program review activities had led to some confusion with regard to schedule requirements and policies. Shea pointed out that in some instances subsystem delivery schedules had been established which were inconsistent with the overall program. Where this had occurred, prompt action by the Subsystems Managers was required to recover lost ground. Shea then laid down specific ground rules to be followed, and requested that waivers of these ground rules be submitted no later than August 15, along with a demonstration that reasonable alternatives had been investigated. Only the ASPO Manager would approve any waivers.
MSC's Assistant Director for Flight Operations, Christopher C. Kraft, Jr., told ASPO Manager Joseph F. Shea that postlanding operational procedures require that recovery force personnel have the capability of gaining access into the interior of the CM through the main crew hatch. This was necessary, he said, so recovery force swimmers could provide immediate aid to the crew, if required, and for normal postlanding operations by recovery engineers such as spacecraft shutdown, crew removal, data retrieval, etc.
Kraft said the crew compartment heatshield might char upon reentry in such a manner as to make it difficult to distinguish the outline of the main egress hatch. This potential problem and the necessity of applying a force outward to free the hatch might demand use of a "crow bar" tool to chip the ablator and apply a prying force on the hatch.
Since this would be a special tool, it would have to be distributed to recovery forces on a worldwide basis or be carried aboard the spacecraft. Kraft requested that the tool be mounted onboard the spacecraft in a manner to be readily accessible. He requested that the design incorporate a method to preclude loss of the tool - either by designing the tool to float or by attaching it to the spacecraft by a lanyard.
Owen E. Maynard, Systems Engineering Division chief, summarized for ASPO Manager Joseph F. Shea the recovery requirements for Apollo spacecraft. The CM must float in a stable, apex-up attitude, and all of the vehicle's recovery aids (uprighting system, communications, etc.) must be operable for 48 hrs after landing. In any water landing within 40 degrees north or south latitude, the Landing and Recovery Division had determined, the crew either would be rescued or recovery personnel would be in the water with the CM within this 48-hr period. Thereafter, Maynard said, the spacecraft had but to remain afloat until a recovery ship arrived - at most, five days.
Owen E. Maynard, Systems Engineering Division chief, advised his branch managers of the U.S. Public Health Service's (PHS) growing concern that Apollo spacecraft and crews might bring organisms back from the moon. PHS feared that such organisms would be "capable of multiplying in the earth environment and [that] precautionary measures must be undertaken to prevent global exposure." Therefore, Maynard told his group, PHS believed that the CM, its environment, and its crew must not be allowed to contact the earth's environment. Maynard further advised that efforts were already underway to define the design of an isolation facility, and isolation facilities for the recovery ships were being contemplated.
As a result of this strong stand by PHS, Maynard said, "It appears that ASPO will soon be requested to show what spacecraft measures are being taken to assure that the CM environment will not be exposed to the earth atmosphere. The spacecraft," Maynard told his group - who already knew as much - "has not been designed to preclude CM environment exposure." Actually, much the opposite had long been assumed to be part of normal operating procedures. Maynard therefore ordered subsystem managers to review their individual systems to determine:
A North American layout of the volume swept by the CM couch and crewmen during landing impact attenuation showed several areas where the couch and or crewmen struck the CM structure or stowed equipment. One area of such interference was that the center crewman's helmet could overlap about four inches into the volume occupied by the portable life support system (PLSS) stowed beneath the side access hatch. The PLSS stowage was recently changed to this position at North American's recommendation because the original stowage position on the aft bulkhead interfered with the couch attenuation envelope. The contractor was directed by MSC to explain this situation.
At-sea operational qualification tests, using boilerplate 29 to simulate spacecraft 009, were completed. All mechanical system components performed satisfactorily, except for the recovery flashing light. Test results were:
MSC analysis of Grumman ground support equipment (GSE) showed that a serious problem in manufacturing and delivery of GSE would have a significant program impact if not corrected immediately. Information submitted to NASA indicated a completion rate of 35 percent of that planned. Grumman was requested to initiate action to identify causes of the problem and take immediate remedial action. A formal recovery plan was to be submitted to NASA, considering the following guidelines:
A memorandum for the file, prepared by J. S. Dudek of Bellcomm, Inc., proposed a two-burn deboost technique that required establishing an initial lunar parking orbit and, after a coast phase, performing an added plane change to attain the final lunar parking orbit. The two-burn deboost technique would make a much larger lunar area accessible than that provided by the existing Apollo mission profile, which used a single burn to place the CSM and LM directly in a circular lunar parking orbit over the landing site and would permit accessibility to only a bow-tie shaped area approximately centered about the lunar equator. On August 1, the memo was forwarded to Apollo Program Director Samuel C. Phillips, stating that the trajectory modification would increase the accessible lunar area about threefold. The note to Phillips from R. L. Wagner stated that discussions had been held with MSC and it appeared that the flight programs as planned at the time could handle the modified mission.
MSC Director Robert R. Gilruth informed MSFC Director Wernher von Braun that for the past two years MSC had studied the use of the mapping and survey system (M&SS) in conjunction with the Apollo program. The system objective would be lunar mapping and landing site certification, and management responsibility was assigned to the MSC Experiments Program Office. System parameters had been established and a decision made to configure the M&SS hardware and supporting systems in a cylindrical container. The container - a "payload module" - would be carried in the spacecraft-LM adapter in place of the LM during the boost phase of flight. The payload module would have docking capability with the CSM like the LM's and, in the docked mode, would map and survey the moon in a programmed lunar orbit.
The M&SS experiment had already been funded by NASA OMSF and would support five possible flights beginning with AS-504. Gilruth forwarded a statement of work and requested MSFC to study it and furnish MSC a cost estimate, technical proposal, and management plan by July 29.
Robert O. Aller, NASA OMSF, told Apollo Program Director Samuel C. Phillips that considerable analysis, planning, and discussion had taken place at MSC on the most effective sequence of Apollo missions following the first manned flight [Apollo 7]. The current official assignments included three CSM/LM missions for CSM/LM operations, lunar simulation, and lunar capability. MSC's Flight Operations Directorate (FOD) had offered an alternate approach of that sequence by proposing that the third mission be a lunar-orbit mission rather than a high earth-orbit mission. Aller preferred the FOD proposal, since it would offer considerable operational advantages by conducting a lunar-orbital flight before the lunar landing. He recommended Phillips consider that sequence of missions and that consideration be given to including it as a prime or alternate mission in the Mission Assignments Document. "Identifying it in that document," Aller said, "would initiate the necessary detailed planning."
In an exchange of correspondence, KSC Director Kurt H. Debus and MSC Director Robert R. Gilruth agreed that close coordination was required between the two Centers regarding launch site recovery and rescue in the event of malfunction leading to an unsuccessful abort before or just after ignition during a launch phase. Coordinated recovery and rescue plans were being formulated for such an emergency. Plans would also include the Department of Defense Eastern Test Range and required coordination with DOD. On December 19 Debus was informed by NASA Hq. that his proposal for a slide wire emergency system had been reviewed and approved.
NASA announced an Apollo mission schedule calling for six flights in 1968 and five in 1969. NASA Associate Administrator for Manned Space Flight George E. Mueller said the schedule and alternative plans provided a schedule under which a limited number of Apollo command and service modules and lunar landing modules, configured for lunar landing might be launched on test flights toward the moon by the end of the decade. Apollo/uprated Saturn I flights were identified with a 200 series number; Saturn V flights were identified with a 500 series number. The 1968 schedule was:
These flights would be flown in the above order and as rapidly as all necessary preparations could be completed.
The 1969 flight schedule called for five manned Apollo/Saturn V flights, AS-505 through AS-509. Four of these-505, 506, 507, and 508-were programmed as lunar mission development flights or lunar mission simulations. It was considered possible that the lunar landing could be made on Apollo/Saturn 509, but it was also possible this might be delayed until one of the remaining six Saturn V flights.
Eberhard F. M. Rees, head of the Apollo Special Task Team at North American Rockwell, met with Kenneth S. Kleinknecht, MSC, and Martin L. Raines, Manager of the White Sands Test Facility, to review the team's recent operations and the responses of North American and its numerous subcontractors to the team's recommendations. Kleinknecht listed what he thought were the chief problems facing the CSM program: the S-band highgain antenna (which he said should be turned over entirely to the task team for resolution); the parachute program; the environmental control system; and contamination inside the spacecraft. He urged that the team take the lead in developing solutions to these problems.
James P. Nolan, Jr., Chief of Plans, NASA OMSF, wrote Mission Operations Director John D. Stevenson describing a potential post-reentry fire hazard in the command module. A hazard might result from incomplete mixing of pure oxygen in the cockpit with normal air after landing, which could produce pockets of almost pure oxygen in closed cabinets, equipment bays, wire bundles, and interstices of the spacecraft. (Two test chamber explosions and fires had occurred at Douglas Aircraft Co. under similar conditions during the early 1950s, he advised.) Nolan suggested that the potential fire hazard be critically reviewed, including possible additional chamber flammability testing. Several weeks later, Stevenson informed Apollo Program Director Samuel C. Phillips that he had discussed Nolan's ideas with MSC Director Robert R. Gilruth, ensuring attention by the Flammability Review Board. He reported that MSC was planning an additional series of chamber tests to determine whether such a fire hazard actually existed.
NASA Hq. asked that MSC consider a variety of lunar photographic operations from orbit during manned landing missions. Cancellation from Apollo of the lunar mapping and survey system had eliminated any specially designed lunar photographic capability; but photography was still desired for scientific, operational, and contingency purposes. Presence of the CSM in orbit during manned landing missions, Headquarters OMSF said, would be a valuable opportunity, however limited, for photographic operations. MSC was asked to evaluate these operations to define whatever hardware and operational changes in Apollo might be required to capitalize upon this opportunity.
Howard W. Tindall, Jr., Chief of Apollo Data Priority Coordination, reported that several meetings devoted to the question of the LM's status immediately after touching down on the lunar surface, had reached agreement on several operational techniques for a "go/no go" decision. Basically, the period immediately after landing constituted a system evaluation phase (in which both crew and ground controllers assessed the spacecraft's status) - a period of about two minutes, during which immediate abort and ascent was possible. Given a decision at that point not to abort, the crew would then remove the guidance system from the descent mode and proceed with the normal ascent-powered flight program (and an immediate abort was no longer possible). Assuming permission to stay beyond this initial "make ready" phase, the crew would then carry out most of the normal procedures required to launch when the CM next passed over the landing site (some two hours later).
David B. Pendley, Technical Assistant for Flight Safety at MSC, recommended to ASPO Manager George M. Low an official policy position for landings on land. Pendley stated that despite all efforts by the Center's Engineering and Development Directorate to develop a safe land-landing capability with the CSM, the goal could not be attained. The best course, he told Low, was to accept the risk inherent in the fact that a land landing could not be avoided in an early launch abort-accept the risk openly and frankly and to plan rescue operations on the premise of major structural damage to the spacecraft. "If we do not officially recognize the land landing hazard," Pendley said, "this will place us in an untenable position should an accident occur, and will further prejudice the safety of the crew by continuing a false feeling of security on the subject."
The Apollo Crew Safety Review Board met to assess land landing of the CSM in the area of the launch site if a flight were aborted just before launch or during the initial phase of a flight. In general the Board was satisfied with overall planned recovery and medical operations. The only specific item to be acted on was some means of purging the interior of the spacecraft to expel any coolant or propellant fumes that might be trapped inside the cabin. The Board was also concerned about the likelihood of residual propellants trapped inside the vehicle even after abort sequence purging, a problem that MSC secured assistance from both the Ames and Lewis Research Centers to solve. At the Board's suggestion, MSC's Crew Systems Division also investigated the use of a helmet liner for the astronauts to prevent head injury upon impact. Finally, the Board recommended continued egress training with fully suited crews, including some night training.
NASA Hq. released a 12-month forecast of manned space flight missions, reflecting an assessment of launch schedules for planning purposes. Five flights were scheduled for the remainder of 1969:
The MSF Management Council, meeting at KSC, agreed that MSC would take the following actions for augmenting the capability of the Apollo system to accomplish a successful lunar landing mission and for planning further lunar exploration:
In a report to the Administrator, the Associate Administrator for Manned Space Flight summed up the feeling of accomplishment as well as the problem of the space program: "The phenomenal precision and practically flawless performance of the Apollo 9 lunar module descent and ascent engines on March 7 were major milestones in the progress toward our first manned landing on the moon, and tributes to the intensive contractor and government effort that brought these two complex systems to the point of safe and reliable manned space flight. The inevitable developmental problems that plagued the LM propulsion system were recurring items in our management reporting, and the fact that essentially all major test objectives were met during last Friday's flight operations is an outstanding achievement. The earth orbital simulations of the lunar descent, ascent, rendezvous, and docking maneuvers, taking Astronauts McDivitt and Schweickart 114 miles [183.4 km] away from the CSM piloted by Dave Scott and safely back, were a measure of the skill of the Apollo 9 crew and the quality of the hardware they were flying."
NASA announced that Apollo 10, scheduled for launch May 18, would be a lunar orbit mission during which two astronauts would descend to within 15,240 meters of the moon's surface. The decision followed reviews of technical and operational data from the Apollo 9 earth-orbit mission. The prime crew would be astronauts Thomas P. Stafford, spacecraft commander; John W. Young, command module pilot; and Eugene A. Cernan, lunar module pilot. Backup crew members were L. Gordon Cooper, Jr., Donn F. Eisele, and Edgar D. Mitchell. With the exception of the actual landing, the mission plan was the same as for the lunar landing mission. Stafford and Cernan were to enter the LM, separate from the CSM, descend twice to within 16 kilometers of one of the preselected landing sites, and then rendezvous and dock with the CSM. Because of propellant limitations in the ascent stage, landing and subsequent liftoff from the moon would be impossible.
In a telephone conference, MSC personnel and members of the Interagency Committee on Back Contamination agreed to eliminate the requirement for a postlanding ventilation filter for Apollo 12, approve a plan for sterilization of the CM in the Lunar Receiving Laboratory (LRL), release the spacecraft at the same time as the crew release, and approve the LRL Bioprotocol Summary. The ICBC planned to meet on June 5 to complete planning and documentation for Apollo 11.
The Interagency Committee on Back Contamination met in Atlanta, Ga. Basing its decision on medical and biological data obtained during a 21-day observation period, the committee lifted the quarantine on the Apollo 11 crew and the personnel in quarantine with the crew. The CSM was also released from quarantine. However, all loose equipment removed from the spacecraft and held in the Lunar Receiving Laboratory would remain in quarantine until the lunar samples were released. The committee also agreed that a postlanding ventilation filter would not be required on Apollo 12.
The Interagency Committee on Back Contamination recommended changes in Apollo mission recovery procedures, including: