North American gave a presentation at MSC on the block change concept with emphasis on Block II CSM changes. These were defined as modifications necessary for compatibility with the LEM, structural changes to reduce weight or improve CSM center of gravity, and critical systems changes. (Block I spacecraft would carry no rendezvous and docking equipment and would be earth-orbital only. Block II spacecraft would be flight-ready vehicles with the final design configuration for the lunar missions.)

NASA and North American discussed visibility requirements on the CM and came to the following conclusions: the contractor would provide four portholes in the protective shroud so the astronauts could see through both side and forward viewing windows, and ensure that all windows were clean after launch escape tower separation. North American proposed the addition to Block II CM of a collimated optical device for orientation and alignment during docking. MSC Flight Crew Operations Directorate recommended that mirrors be added to increase external and internal field of vision.

The Block II CSM configuration was based on three classes of changes: mandatory changes necessary to meet the

1. Functional requirements of the lunar mission.
2. Manufacturing or fabrication changes (identified only with improved fabrication techniques).
3. Technically desirable and weight reduction changes.

North American held a design review of the CM heatshield substructure. Use of titanium in place of stainless steel was being evaluated as part of a weight reduction study for the Block II spacecraft. Added reliability and a weight saving of several hundred pounds might be achieved thereby. Three factors would be considered: the brittleness of stainless steel at extremely cold temperatures, the higher cost of titanium, and the verification of diffusion bonding of titanium honeycomb.

To verify a narrower hatch configuration proposed for Block II spacecraft, North American evaluated the capability of an astronaut wearing a pressurized space suit and a portable life support system to pass through the main hatch of the CM for extravehicular activities. Subjects were able to enter and leave the mockup without undue difficulty despite the presence of gravity.

At the April 7-8 NASA-North American Technical Management Meeting (the first of these meetings to be held at MSC's new home, "NASA Clear Lake Site 1"), ASPO Manager Joseph F. Shea summarized his office's recent activities concerning the Block II spacecraft. He spelled out those areas that ASPO was investigating - which included virtually the whole vehicle between escape tower and service engine bell. Shea outlined procedures for "customer and contractor" to work out the definitive Block II design, aiming at a target date of mid-May 1965. These procedures included NASA's giving North American descriptions of its Block II work, estimates of weight reduction, and a set of ground rules for the Block II design. And to ensure that both sides cooperated as closely as possible in this work, Shea named Owen E. Maynard, Chief of MSC's Systems Engineering Division, and his counterpart at Downey, Norman J. Ryker, Jr., to "honcho" the effort.

Joseph F. Shea, ASPO Manager, in a letter to North American's Apollo Program Manager, summarized MSC's review of the weight status of the Block I and the design changes projected for Block II CSM's.

The Block II design arose from the need to add docking and crew transfer capability to the CM. Reduction of the CM control weight (from 9,500 to 9,100 kilograms (21,000 to 20,000 pounds)) and deficiencies in several major subsystems added to the scope of the redesign. Additional Details: here....

North American conducted a preliminary study on removal of one of three fuel cells from the Block II CSM. The contractor predicted a total weight saving of about 168 kilograms (370 pounds), with potential indirect reductions in the cryogenic systems, but this change would require a significant increase in reliability.

MSC's Apollo Spacecraft Program Office (ASPO) approved a plan (put forward by the MSC Advanced Spacecraft Technology Division to verify the CM's radiation shielding. Checkout of the radiation instrumentation would be made during manned earth orbital flights. The spacecraft would then be subjected to a radiation environment during the first two unmanned Saturn V flights. These missions, 501 and 502, with apogees of about 18,520 km (10,000 nm), would verify the shielding. Gamma probe verification, using spacecraft 008, would be performed in Houston during 1966. Only Block I CM's would be used in these ground and flight tests. Radiation shielding would be unaffected by the change to Block II status.

North American and MIT Instrumentation Laboratory representatives met in Houston to discuss electrical power requirements for the guidance and control systems in Block II CMs. They had determined the additional electrical power needed for the guidance and control system 24 volts was available,

Eagle-Picher Company completed qualification testing on the 25-amperehour reentry batteries for the CM. Shortly thereafter, Eagle-Picher received authorization from North American to proceed with design and development of the larger 40-ampere-hour batteries needed for the later Block I and all Block II spacecraft.

The Guidance and Control Implementation Sub-Panel of the MSC-MSFC Flight Mechanics Panel defined the guidance and control interfaces for Block I and II missions. In Block II missions the CSM's guidance system would guide the three stages of the Saturn V vehicle; it would control the S- IVB (third stage) and the CSM while in earth orbit; and it would perform the injection into a lunar trajectory. In all of this, the CSM guidance backed up the Saturn ST-124 platform. Actual sequencing was performed by the Saturn V computer.

North American and Honeywell reviewed the Block II CSM entry monitor subsystem's compatibility with the stabilization and control system. The proposed configuration, they found, combined maximum reliability with minimum size and weight and would provide adequate mission performance.

ASPO's Operations Planning Division defined the current Apollo mission programming as envisioned by MSC. The overall Apollo flight program was described in terms of its major phases: Little Joe II flights (unmanned Little Joe II development and launch escape vehicle development); Saturn IB flights (unmanned Saturn IB and Block I CSM development, Block I CSM earth orbital operations, unmanned LEM development, and manned Block II CSM/LEM earth orbital operations); and Saturn V flights (unmanned Saturn V and Block II CSM development, manned Block II CSM/LEM earth orbital operations, and manned lunar missions).

MSC informed North American that a flashing light on the CSM, as an aid for visual rendezvous, was not required. (A request for some such device had been generated at the Block II mockup review.) Houston's position was based on the current CSM/LEM configuration, which called for rendezvous radar on both spacecraft and the ability of both vehicles to effect the rendezvous using either its own radar or that in the target vehicle.

MSC's Assistant Director for Flight Crew Operations, Donald K. Slayton, told the Apollo Program Manager that the current display and keyboard (DSKY) for the Block II CSM and for the LEM were not compatible with existing display panel design of both vehicles from the standpoint of lighting, nomenclature presentation, and caution warning philosophy. In his memorandum, Slayton pointed out mandatory operational requirements of the DSKY to ensure compatibility and consistency with the existing spacecraft display panel design.

With reference to lighting, he said all numerics should be green, nomenclature and status lights white, and caution lights should be aviation yellow. All panel lighting should be dimmable throughout the entire range of brightness, including off.

In regard to nomenclature, Slayton pointed out that abbreviations on the DSKY should conform to the North American Interface Control Document (ICD). The referenced ICD was being reviewed by Grumman and North American and was scheduled to be signed December 1, 1964.

Referring to the caution and warning system, he pointed out that all caution lights on the DSKY should be gated into the primary navigation and guidance system (PNGS) caution light on the main instrument panel of both vehicles and into the PNGS caution light on the lower equipment bay panel of the CM.

Slayton requested that preliminary designs of the DSKY panel be submitted to the Subsystem Managers for Controls and Displays for review and approval.

Officials from North American and MSC Crew Systems Division defined the container design and stowage of survival kits in the Block II CM. The equipment would be packed in fabric rucksacks and would be installed in the spacecraft's stowage compartment. (This method eliminated a removable hard container used in the Block I vehicle and would save weight.)

MSC informed North American that the Center would furnish a VHF transmitter to serve as a telemetry dump for all manned Block I flights. This would permit wide flexibility in testing the CSM S-band's compatibility with the Manned Space Flight Network prior to Block II missions.

The Configuration Control Panel approved a deployment angle of 45 degrees for the adapter panels on Block I flights. North American anticipated no schedule impact. MSC and North American were jointly evaluating the acceptability of this angle for Block II missions as well. A most important consideration was the necessity to communicate via the CM's high-gain antenna during the transposition and docking phase of the flight.

MSC approved plans put forth by North American for mockups of the Block II CSM. For the crew compartment mockup, the company proposed using the metal shell that had originally been planned as a simulator. Except for the transfer tunnel and lighting, it would be complete, including mockups of all crew equipment. Additional Details: here....

ASPO's Systems Engineering Division (SED) investigated the possibility of partial donning of the space suit (sans helmet and gloves) and the consequent effects upon operation of the CM environmental control system (ECS). (Current ECS design called for shirtsleeve and full-suited operations.) The systems engineers found that, with vehicle reliability based upon shirtsleeve environments, wearing part of the suit contributed little toward protecting the astronaut against loss of cabin pressure.

Most pressure-seal failures in the spacecraft would still allow the astronaut time to don the complete suit. Catastrophic failures (i.e., loss of windows or hatches) were highly improbable, but if one of this type occurred, depressurization would be so rapid as to preclude the astronaut's donning even a part of the suit. Actually, overall mission reliability was greatest with the shirtsleeve environment; continuous suit wear degraded the garment's reliability for the lunar exploration phase of the flight. Moreover, a number of design changes in the spacecraft would be required by partial suit wear.

SED concluded that, to build confidence in the spacecraft's pressurization system, Block I CM's should be outfitted for partial suit wear. In Block II vehicles the suit should not be worn during translunar mission phases (again because of mission reliability). SED recommended to the ASPO Manager, therefore, that he direct North American to incorporate provisions for partial suit wear in Block I and to retain the shirtsleeve concept for the Block II spacecraft.

The Preliminary Design Review of the Block II CM was held at North American's Downey, Calif., plant. Ten working groups evaluated the spacecraft design and resolved numerous minor details. They then reported to a review board of NASA and North American officials. Additional Details: here....

The first meeting of the Configuration Control Board was held at MSC with ASPO Manager Joseph F. Shea as chairman. Approval was given to delete 10 Apollo guidance and navigation systems; and W. F. Rector III was directed to look into the use of computers and prototype units for electronic systems integration. In other actions, a decision on changes to CSM specifications to provide for the heavyweight LEM (a proposed increase from 12,705 to 14,515 kg (28,000 to 32,000 lbs)) was deferred until the next meeting; and Owen Maynard was directed to identify all Block II changes that must be implemented regardless of impact and have them ready for Board action by February 18, 1965.

MSC was studying several approaches to the problems of automatic thermal control and automatic reacquisition of the earth by the S-band high-gain antenna while the CSM circled the moon. (The Block II spacecraft, MSC had stated, must have the ability to perform these functions wholly on its own. During an extended stay of the LEM on the lunar surface, when the CSM pilot needed uninterrupted sleep periods, antenna reacquisition was absolutely essential for telemetering data back to earth. And although the requirements for passive thermal control were not yet well defined, the spacecraft's attitude must likewise be automatically controlled.)

Robert C. Duncan, chief of the MSC Guidance and Control Division, presented his section's recommendations for solving these problems, which ultimately won ASPO's concurrence. Precise spacecraft body rates, Duncan said, should be maintained by the stabilization and control system. The position of the S-band antenna should be telemetered to the ground, where the angle required for reacquisition would be computed. The antenna would then be repositioned by commands sent through the updata link.

MSC negotiated a backup Block II space suit development program with David Clark Company, which paralleled the Hamilton Standard program, at a cost of $176,000. Criteria for selecting the suit for ultimate development for Block II would be taken from the Extravehicular Mobility Unit Design and Performance Specification. A selection test program would be conducted at MSC using the CM mockup, the lunar simulation facility, and the LEM mockup.

MSC canceled plans (originally proposed by North American) for a device to detect failures in the reaction control system (RCS) for Block I CSMs. This was done partly because of impending weight, cost, and schedule penalties, but also because, given an RCS failure during earth orbit, the crew could detect it in time to return to earth safely even without the proposed device. This action in no way affected the effort to devise such a detection system for the Block II CSM or the LEM, however.

MSC relayed to NASA Headquarters North American's cost estimates for airlocks on the Apollo CM:

During late February and early March, North American completed a conceptual design study of an airlock for the Block I CMs. Designers found that such a device could be incorporated into the side access hatch. A substitute cover for the inner hatch and a panel to replace the window on the outer hatch would have to be developed, but these modifications would not interfere with the basic design of the spacecraft.

MSC directed North American to delete the rendezvous radar from Block II CSMs. On those spacecraft North American instead would install LEM rendezvous radar transponders. Grumman, in turn, was ordered to halt its work on the CSM rendezvous radar (both in-house and at RCA) as well as all support efforts. At the same time, however, the company was directed to incorporate a tracking light on the LEM (compatible with the CSM telescope sextant) and to modify the spacecraft's VHF equipment to permit range extraction in the CSM.

To eliminate interference between the S-IVB stage and the instrument unit, MSC directed North American to modify the deployment angle of the adapter panels. Originally designed to rotate 170 degrees, the panels should open but 45 degrees (60 degrees during abort), where they were to be secured while the CSM docked with and extracted the LEM.

But at this smaller angle, the panels now blocked the CM's four flush- mounted omnidirectional antennas, used during near-earth phases of the mission. While turning around and docking, the astronauts thus had to communicate with the ground via the steerable high gain antenna. For Block II spacecraft, therefore, MSC concurrently ordered North American to broaden the S-band equipment's capability to permit it to operate within 4,630 km (2,500 nm) of earth.

ASPO proposed deletion of a liftoff light in the Block II CM. The Block I design provided a redundant panel light which came ON at liftoff as a part of the emergency detection system (EDS). This light gave a cue to the pilot to verify enabling of the EDS automatic abort, for which manual backup was provided. The Block II CM would incorporate improved EDS circuitry without manual backup. Deletion of the liftoff light in the CM was proposed to save weight, power, space, and reliability, and to eliminate a crew distraction during the boost phase of flight.

Structures and Mechanics Division engineers were studying several schemes for achieving the optimum weight of Block II CMs without compromising landing reliability: reducing velocity by retrorockets or "explosions" in the parachutes; controlling roll attitude to 0 degrees at impact through a "rotatable pot" structure; changing landing medium (i.e., shape hole in water and/or aeration of the water).

North American summarized its position on the design of the CM for earth impact in a letter to MSC. A number of meetings had taken place since the NASA North American Technical Management Meeting February 25, 1964, at which the decision was made to reorient Apollo impact to water as the primary landing site.

The letter reviewed the history of boilerplate 28 drop tests and a series of MSC North American meetings during the last two months of 1964 and the first two of 1965. On February 12, at a meeting at Downey, California, North American had recommended:

• Design for 0.99999 criteria.
• Retain the 27.5 degrees hang angle to eliminate the requirement for redesign of upper crew compartment side wall. The dual hang angle configuration should be eliminated for spacecraft 017 and subsequently through Block II.
• Allow plastic deformation of the aft heatshield.
• Continue investigation of possible upper deck and tunnel problems.
• Fly spacecraft 009 with a probability of success at water impact of 0.999, and continue boilerplate 28 testing to give assurance of meeting this criterion.

At the time of the April 27 letter, North American was implementing the design changes defined in the Apollo CM design changes for water impact. The changes were based on North American's best understanding of agreements between it and MSC regarding criteria, loads, definition of the ultimate land envelope, structural analysis, and the requirement that no-leakage integrity within the ultimate load level be demonstrated by test.

Although North American was including real-time digital command equipment in Block II CSMs (as NASA had directed), the firm recommended that such equipment not be placed on Block I vehicles. North American based their contention on two factors:

1. the anticipated cost and schedule impacts; and
2. command capability was not essential during earth orbital flights.

In response to a query, Apollo Program Director Samuel C. Phillips told NASA Associate Administrator for Manned Space Flight George E. Mueller that plans to use VHF communications between the CSM, LEM, and extravehicular astronauts and to use X-band radar for the CSM/LEM tracking were reviewed. Bellcomm reexamined the merits of using the Unified S-Band (USB) type which would be installed in the CSM and LEM for communication with and tracking by the earth.

It was found that no appreciable weight saving or weight penalty would result from an all USB system in the Apollo spacecraft. Also, it was determined there would be no significant advantage or disadvantage in using the system. It was noted, however, that implementation of an all S-band system at that stage of development of the design of the CSM, LEM, and astronaut equipment would incur an obvious cost and schedule penalty.

Memorandum, Phillips to Mueller, "Use of Only Unified S-Band Communication Equipment in Apollo Spacecraft," May 5, 1965.

May 6

After lengthy investigations of cost and schedule impacts, MSC directed North American to incorporate airlocks on CMs 008 and 014, 101 through 112, and 2H-1 and 2TV-1. The device would enable astronauts to conduct experiments in space without having to leave their vehicle. Initially, the standard hatches and those with airlocks were to be interchangeable on Block II spacecraft. During October, however, this concept was changed: the standard outer hatch would be structured to permit incorporation of an airlock through the use of a conversion kit (included as part of the airlock assembly); and when an airlock was installed, an interchangeable inner hatch would replace the standard one.

MSC directed North American to install Block II-type, flush-mounted omni-directional S-band antennas on CMs 017 and 020. These antennas would survive reentry and thus would afford telemetry transmissions throughout the flight. On June 25, the Center ordered that they be installed in the toroidal (doughnut shaped) section of the aft heatshield.

To aid reacquisition and tracking of the high-gain antenna, MSC directed North American to study the feasibility of an inertial reference system on Block II spacecraft, one that would use rate signals from the CSM's stabilization and control system. Without this system, the astronauts would have to perform anywhere from 250 to 500 antenna reacquisitions during a single lunar mission. And during sleeping periods, when the CM pilot was alone in the vehicle, it was mandatory that the antenna automatically reacquire the earth.

ASPO Manager Joseph F. Shea replied to a recommendation by the Assistant Director for Flight Operations to incorporate warning lights in Block I and II CMs to indicate failure of the gimbal actuator secondary drive motors. ASPO decided that no failure indication would be provided for the redundant drive motors in Block I spacecraft because:

1. in-flight checkout procedures would provide for exercising the gimbal actuators by the primary and secondary drive motors prior to service propulsion system burns; and
2. all manned Block I missions would be conducted in earth orbit and reaction control system deorbit capability was stipulated.

ASPO advised North American that, at present, no unmanned flights were planned for the Block II CM. After the company concluded its own analysis of Apollo requirements, MSC would determine whether the heatshield must be verified prior to manned missions. But because of the long "lead time" involved, North American should continue securing the requisite instrumentation pending a final decision.

MSC reviewed a lighting mockup of the crew compartment in the Block II CM. The design concept, though needing further refinement, was deemed acceptable. Engineers from Crew Systems Division found that lights on the fingertips of the suit gloves worked quite well; optimum positioning was as yet undetermined, however. At the same time, MSC reviewed the design of the Block I side hatch (i.e., not modified to meet Block II extravehicular requirements). Reviewers found North American's major problems were warpage and crew ingress from space. Further, the design of both side hatches needed "additional coordination" with that of the umbilical access arm of the launch tower to ensure compatibility.

MSC and North American discussed the brittleness of the boost protective cover and the possibility that, during tower jettison or abort, the cover might break up and cause damage to the spacecraft. Having investigated a number of various materials and construction techniques, North American recommended adding a nylon fabric to strengthen the structure. Company engineers believed that, thus reinforced, the cover would be less likely to tear apart in flight. Even though this would increase the weight of the cover by about 27 kg (60 lbs), MSC concurred. The change applied to both Block I and Block II CMs, and was effective for spacecraft 002, 009, and all subsequent vehicles.

Independent studies were made at MSC and North American to determine effects and impact of off-loading certain Block II service propulsion system components for Saturn IB missions. The contractor was requested to determine the weight change involved and schedule and cost impact of removing one oxidizer tank, one fuel tank, one helium tank and all associated hardware (fuel and oxidizer transfer lines, propellant quantity sensors and certain gaging wire harnesses) from CSM 101 and CSM 103. The MSC study was oriented toward determining technical problems associated with such a change and the effects on spacecraft operational requirements. The North American study indicated that removing the equipment would save about 690 000, along with a weight reduction of approximately 454 kg (1,000 lbs). Additional Details: here....

The operational requirement for Block I and Block II CSM HE orbital communications capability was investigated. ASPO requested that appropriate contract direction and specification change notices be submitted immediately to eliminate this capability from the Block II CSM and the practicality of eliminating the HE orbital capability from the Block I CSM be investigated.

Structures and Mechanics Division (SMD) presented meteoroid protection figures for the Apollo CSM. (During April, General Electric (GE) had developed reliability estimates for the LEM, based on revised design criteria, for the 8.3-day reference mission. The probability for mission success, GE had found, was 0.9969.) SMD'S figures were:

All of the above figures, both GE's and SMD's, were derived from the inherent protection afforded by the spacecraft's structure. Thus no additional meteoroid shielding was needed. (Meteoroid protection would still be required, of course, during extravehicular operations.)

North American began redesigning the side hatch mechanism in the CM to satisfy the requirement for extravehicular transfer from Block II spacecraft. Two basic modifications to the Block I mechanism were required: (1) enlarging it to overcome thermal warpage; and (2) adding some hinge retention device to secure the hatch once it was opened.

North American and MSC attended a design review at Ling-Temco-Vought on the environmental control system radiator for the Block II CSM. After reviewing design and performance analyses, the review team approved changes in testing and fabrication of test hardware.

North American and its subcontractor, LTV, conducted a design review on the environmental control system radiator for the Block II CSM. Both parties agreed upon a backup effort (i.e., a narrower selective stagnation panel), which would be more responsive to thermal changes in the spacecraft. Testing of this backup design could follow that of the prototype and still meet the design release.

North American proposed an additional pane of glass for the windows on Block II CMs. Currently, both blocks of spacecraft had one pane. Should meteoroids pit this pane, the window could fail during reentry at lunar velocities. The meteoroid protection group in Structures and Mechanics Division were evaluating North American's proposal, which would add about 10.43 kg (23 lbs) to the vehicle's weight. No such added protection was required on Block I spacecraft.

The Critical Design Review (CDR) of the Block II CSM was scheduled to be conducted in November and December 1965, with the first phase being held November 15-18, and the second phase December 13-17.

The first phase activity would be a review of drawings, schematics, procurement specifications, weight status, interface control drawings, failure analysis, proposed specification change notices, and specification waivers and deviations. The second phase of the review would be a physical inspection of the mockup of the Block II CSM.

The review would be conducted by review teams organized in the several areas and headed by team captains, as follows: Structures and Propulsion, O. Ohlsson; Communications, Instrumentation, and Electrical Power, W. Speier; Stabilization and Control, Guidance and Navigation, A. Cohen; Crew Systems, J. Loftus; and Mission Compatibility and Operations, R. Battey.

In the absence of a firm requirement, and because of limited utility, reported Robert C. Duncan, Chief of the Guidance and Control Division, the horizon photometer and star tracker were being deleted from the primary guidance system in Block I CSMs. (Block II guidance systems would still contain the devices.)

The Block II CSM Critical Design Review (CDR) was held at North American, Downey, Calif. The specifications and drawings were reviewed and the CSM mockup inspected. Review Item Dispositions were written against the design where it failed to meet the requirements.

As a result of the CDR North American would update the configuration of mockup 27A for use in zero-g flights at Wright-Patterson AFB. The flights could not be rescheduled until MSC approved the refurbished mockup as being representative of the spacecraft configuration.

The Block II Apollo food stowage problems were explored at North American. Methods of restraint were resolved to allow accessibility of the man-meal assemblies. The contractor, Melpar, Inc., would rework and reposition mockup man-meal assemblies to conform with suggestions by the Crew Provisions Office of the MSC Apollo Support Office and North American representatives.

A decision made at a Program Management Review eliminated the requirement for a land impact program for the CM to support Block I flights. Post-abort CM land impact for Saturn IB launches had been eliminated from Complex 37 by changes to the sequence timers in the launch escape system abort mode. The Certification Test Specification and related Certification Test Requirements would reflect the new Block II land impact requirements.

NASA Hq. requested the Apollo Spacecraft Program Office at Manned Spacecraft Center to evaluate the impact, including the effect on ground support equipment and mission control, of a dual AS-207/208 flight as early as AS-207 was currently scheduled. ASPO was to assume that launch vehicle 207 would carry the Block II CSM, launch vehicle 208 would carry the lunar excursion module (LEM), and the two launches would be nearly simultaneous. Kennedy Space Center (KSC) and Marshall Space Flight Center (MSFC) were asked to make similar studies for their systems. Response was requested by February 7, 1966.

ASPO Manager Joseph F. Shea informed Apollo Program Director Samuel C. Phillips, in response to a January 28 TWX from Phillips, that MSC had evaluated the capability to support a dual launch of AS-207 208 provided an immediate go-ahead could be given to the contractors. Shea said the evaluation had covered mission planning, ground support equipment (GSE), flight hardware, and operations support. Modifications and additional GSE would be required to update Launch Complex 34 at Cape Kennedy to support a Block II CSM. The total cost of supporting the AS-207/208 dual launch was estimated at $10.2 million for the GSE and additional boiler plate CSM configuration, but Shea added that these costs could be absorbed within the FY 1966 budget. Shea recommended that the dual mission be incorporated into the program.

NASA Hq. requested the MSC Apollo Spacecraft Program Office to reassess the spacecraft control weights and delta-V budget and prepare recommendations for the first lunar landing mission weight and performance budgets. The ASPO spacecraft Weight Report for April indicated that the Block II CSM, when loaded for an 8.3-day mission, would exceed its control weights by more than 180 kilograms and the projected value would exceed the control weight by more than 630 kilograms. At the same time the LEM was reported at 495 kilograms under its control weight. Credit for LEM weight reduction had been attributed to Grumman's Super Weight Improvement Program.

ASPO Manager Joseph F. Shea informed Rocco A. Petrone, KSC, that structural problems in the CSM fuel and oxidizer tanks required standpipe modifications and that they were mandatory for Block I and Block II spacecraft. Retrofit was to be effective on CSM 011 at KSC and other vehicles at North American's plant in Downey, Calif.

In response to a query on needs for or objections to an Apollo spacecraft TV system, MSC Assistant Director for Flight Crew Operations Donald K. Slayton informed the Flight Control Division that FCOD had no operational requirements for a TV capability in either the Block I or the Block II CSM or LM. He added that his Directorate would object to interference caused by checkout, crew training, and inflight time requirements.

MSC Director Robert R. Gilruth asked LaRC Director Floyd Thompson to conduct a study at Langley to familiarize flight crews with CM active docking and to explore problems in CM recontact with the LM and also LM withdrawal. MSC would provide astronaut and pilot-engineer support for the study. Apollo Block II missions called for CM active docking with the LM and withdrawal of the LM from the S-IVB stage, requiring development of optimum techniques and procedures to ensure crew safety and to minimize propellant utilization. LM withdrawal was a critical area because of clearances, marginal flight crew visibility, and mission constraints. Previous simulations at LaRC indicated the possibility of using the Rendezvous Docking Simulator.

NASA Task Team - Block II Redefinition, CSM, was established by ASPO. The team - to be in residence at North American Aviation during the redefinition period - was to provide timely response to questions and inputs on detail design, overall quality and reliability, test and checkout, baseline conditions, configuration control, and schedules.

Astronaut Frank Borman was named Task Team Manager and group leaders were: Design, Aaron Cohen; Quality and Reliability and Test and Checkout Procedures, Scott H. Simpkinson; Materials, Jerry W. Craig; Specifications and Configuration Control, Richard E. Lindeman; and Scheduling, Douglas R. Broome.

The NASA Block II CSM Redefinition Task Team was augmented by the assignment of Gordon J. Stoops as Group Leader-Program Control, with the following functions:

• Liaison with North American Aviation Program Control and Contracts to expedite updating of the contract change authorizations and the issuance of timely program technical direction.
• Liaison with the ASPO CSM project Engineering and Checkout Division and CSM Contract Engineering Branch at MSC to expedite contract change authorizations and ensure timely program technical direction.

Prime and backup crews for Apollo 7 (spacecraft 101) were named, with the assignments effective immediately. The prime crew for the engineering-test-flight mission was to consist of Walter M. Schirra, Jr., commander; Donn F. Eisele, CM pilot; and R. Walter Cunningham, LM pilot. The backup crew was Thomas P. Stafford, commander; John W. Young, CM pilot; and Eugene A. Cernan, LM pilot. Names had been reported to the Senate Committee on Aeronautical and Space Sciences on 9 May.

A Block II spacecraft vibration program was begun to provide confidence in CSM integrity and qualify the hardware interconnecting the subsystems within the spacecraft. A test at MSC was to simulate the vibration environment of max-q flight conditions. The test article was to be a Block II CSM. A spacecraft-LM adapter, an instrumentation unit, and an S-IVB stage forward area simulation would also be used.

MSC notified NASA Hq. that - with the changes defined for the Block II spacecraft following the January 27 Apollo 204 fire and with CSM delivery schedules now reestablished - it was necessary to complete a contract for three additional CSMs requested in 1966. North American Aviation had responded September 15, 1966, to MSC's February 28 request for a proposal, but action on a contract had been suspended because of the AS-204 accident. NASA Hq. on June 27, 1967, authorized MSC to proceed.

W. R. Downs, Special Assistant for Advanced Systems, MSC Structures and Mechanics Division, discovered that bare or defectively insulated silver-covered copper wires exposed to glycol/water solutions would ignite spontaneously and burn in oxygen. Copper wire or nickel-covered copper wire under identical conditions did not ignite. The laboratory results were confirmed in work at the Illinois Institute of Technology. In a June 13 memorandum, the Chief of the Structures and Mechanics Division recommended that if additional testing verified that nickel-coated wires were free of the hazard, consideration should be given to an in-line substitution of nickel-coated wires for silver-coated wires in the LM. It was understood that the Block II CSM already had nickel-coated wires. In a June 20 memo to the ASPO Manager, the Director of Engineering and Development pointed out that silver-plated pins and sockets in connectors would offer the same hazards. He added that Downs had also identified a chelating agent that would capture the silver ion and apparently prevent the reaction chain. In a July 24 memorandum, ASPO Manager George Low said that, in view of recent spills of ethylene glycol and water mixtures, spacecraft contractors North American Aviation and Grumman Aircraft Engineering had been directed to begin actions immediately to ensure that a fire hazard did not exist for the next manned spacecraft. Actions were to include identification of the location of silver or silver-covered wires and pins and of glycol spills.

NASA Office of Manned Space Flight had redefined the Apollo Block II manned mission flight plan, ASPO informed the MSC Director of Science and Applications. The first manned flight plan called for

1. an open-ended mission up to 10 days,
2. sufficient instrumentation,
3. no extravehicular activity,
4. a CSM rendezvous with the S-IVB stage, and
5. no experiments that required spacecraft integration.

The purpose of spacecraft 105 testing was to establish transition relations between the primary and secondary structure that supported systems' interconnecting hardware (wiring, tubing and associated valves, filters, regulators, etc.) and demonstrate structural integrity of the Block II CSM when subjected to qualification vibration environment, with special emphasis on interconnecting hardware. The test vehicle was being configured with complete basic Block II wiring harness and fluid systems. The vehicle would be checked out before and after each phase of testing to verify wiring harness impedance and continuity and fluid systems pressure integrity. The fluid systems would be at operating pressure during the testing.

The Apollo Program Director requested MSC to assign the following experiments to AS-205, spacecraft 101: M006 - Bone Demineralization, M011 - Cytogenic Blood Studies, M023 - Lower Body Negative Pressure, S005 - Synoptic Terrain Photography, and S006 - Synoptic Weather Photography. Additional Details: here....

A CSM shipment schedule, to be used for planning throughout the Apollo program and as a basis for contract negotiations with North American Aviation, was issued by NASA Hq. The schedule covered CSM 101 through CSM 115, CSM 105R, and CSM 020 and the period September 29, 1967, through November 17, 1969.

ASPO announced that a detailed review of the Block II CSM would be held to gain a better understanding of the hardware. ASPO Manager George M. Low pointed out that it had been customary in the Gemini and Apollo Programs to conduct Design Certification Reviews (DCRs) before manned flight of the "first of a kind" vehicle. He added that the detailed review should address itself to design and analysis, test history and evaluation of test results, and the understanding of operational procedures for each element in the CSM. To ensure the most thorough review, MSC divisions would conduct preliminary reviews. The division chiefs would then present their findings to the directorates, the ASPO management, and the MSC Director.

The NASA task team for CSM Block II redefinition, established on April 27, was phased out. During its duration the task team provided timely response and direction in the areas of detail design, overall quality and reliability, test and checkout, baseline specifications, and schedules. With the phaseout of the team, Apollo Spacecraft Program Office policies and procedures would be carried out by the ASPO resident manager. A single informal point of contact was also established between MSC and North American for engineering and design items.

Key dates in the spacecraft 101 schedule were agreed to during a meeting of Samuel C. Phillips, Robert R. Gilruth, George M. Low, and Kenneth S. Kleinknecht with North American management: inspection of wiring, October 7, 1967; completion of manufacturing, December 15, 1967; delivery, March 15, 1968. In addition, several decisions were reached concerning certain systems of spacecraft 101. Among these, it was agreed that the entry monitor system would not be checked out on spacecraft 101.

NASA Hq. informed MSC that NASA Deputy Administrator Robert C. Seamans, Jr., had approved the project approval document authorizing four additional CSMs beyond No. 115A. MSC was requested to proceed with all necessary procurement actions required to maintain production capability in support of projected schedules for these items.

ASPO Manager George Low, in a memorandum to CSM Manager Kenneth Kleinknecht, remarked that he had "just read Dale Myers' letter to you . . . on the subject of Northrop Ventura performance. In addition I have . . . read a letter from Dick Horner to me in response to my letter . . . of September 29, 1967. Additional Details: here....

Walter J. Kapryan of the MSC Resident ASPO at KSC told the KSC Apollo Program Manager that one of the primary test objectives of the SM-102 static-fire test was to determine system deterioration caused by the static-fire sequence and exposure to residual hypergolics trapped in the system during subsequent prelaunch operations. Additional Details: here....

Apollo Program Director Samuel C. Phillips told ASPO Manager George M. Low that a review had begun on the "Apollo Spacecraft Weight and Mission Performance Definition" report dated December 12 and that his letter indicated approval of certain changes either requested or implied by the report. Phillips added that his letter identified a second group of pending changes for which insufficient information was available. He stressed his serious concern over the problem of spacecraft weight growth and said weight must be limited to the basic 45,359-kilogram launch vehicle capability. "According to the progression established in your report, CM's 116 through 119 could exceed the parachute hand-weight capability. I would like to establish a single set of controlled basic weights for the production vehicles. For product improvement changes a good rule is a pound deleted for every pound added. For approved changes to the basic configuration, it is the responsibility of NASA to understand the weight and performance implication of the change and to establish appropriate new control values. . . ."

In response to action required by the CSM 2TV-2 and CSM 101 Wire Board in October 1967, Dale D. Myers, CSM Program Manager at North American Rockwell, submitted to MSC results of a wire improvement study for the umbilical feedthrough area for the lower equipment bay. Additional Details: here....

Design Certification Reviews of CSM 101 and LM-3 were held at MSC. Significant program-level agreements reached included validation of a 60-percent-oxygen and 40-percent-nitrogen cabin atmosphere during launch; reaffirmation of the February 6 Management Council decision that a second unmanned LM flight was not required; and the conclusion that, in light of successful static firing of the 102 service propulsion system and subsequent analysis, a static-firing of the 101 system was not required.

ASPO Manager George M. Low requested Joseph N. Kotanchik to establish a task team to pull together all participants in the dynamic analysis of the Saturn V and boost environment. He suggested that Donald C. Wade should lead the effort and that he should work with George Jeffs of North American Rockwell, Tom Kelly of Grumman and Wayne Klopfenstein of Boeing, and that Lee James of MSFC could be contacted for any desired support or coordination. The team would define the allowable oscillations at the interface of the spacecraft-LM adapter with the instrument unit for the existing Block II configuration, possible changes in the hardware to detune the CSM and the LM, and the combined effects of pogo and the S-IC single-engine-out case. Low also said he was establishing a task team under Richard Colonna to define a test program related to the same problem area and felt that Wade and Colonna would want to work together.

ASPO Manager George M. Low explained to the Apollo Program Director the underlying causes of slips in CSM and LM delivery dates since establishment of contract dates during the fall of 1967. The general excuse, Low said, was that slips were the result of NASA-directed hardware changes. "This excuse is not valid." He recounted how NASA-imposed changes had been under strict control and only essential changes had been approved by the MSC Level II Configuration Control Board (CCB). Additional Details: here....

ASPO Manager George Low advised Apollo program officials at KSC that, to collect adequate data for evaluating any potential toxicological hazard inside the spacecraft, collection of gas samples of the cabin atmosphere must be made for 12 hours during the unmanned altitude chamber test with all systems operating. Low asked that this requirement be included in the spacecraft test procedures. Additional Details: here....

ASPO Manager George M. Low met with Christopher C. Kraft, Jr., and Donald K. Slayton, Directors of MSC Flight and Flight Crew Operations, and several members of their staffs (including astronaut Walter M. Schirra, Jr.) to discuss using the flight combustion stability monitor (FCSM) on the Apollo 7 flight. Additional Details: here....

Dale D. Myers, Apollo CSM Program Manager at North American Rockwell, advised MSC officials of his company's investigation of two pilot-chute riser failures during recent drop tests of the Block II earth-landing system. Should there be any imperfections in either hardware or assembly techniques, Myers explained, the Block II pilot chute and riser system could be a marginal-strength item. Investigations had determined that early manufacturing processes had allowed a differential length between the two plies of nylon webbing in the pilot-chute riser which caused unequal load distribution between the two plies and low total riser strength. Because of the earlier test failures, Myers said, the pilot chute riser had been redesigned. The two-ply nylon webbing had been replaced by continuous suspension lines (i.e., 12 nylon cords) and the 5.5-millimeter-diameter cable was changed to 6.3-millimeter cable. He then cited a series of recent tests that verified the redesigned pilot-chute riser's strength to meet deployment under worst-case operational conditions.

NASA and contractor technicians successfully conducted the final parachute drop test to qualify the Apollo CSM earth-landing system. The Block II ELS thus was considered ready for manned flight after 12 Block I, 4 Block II, and 7 increased-capability Block II Qualification Tests - that had followed 77 Block I, 6 Block II, and 25 increased-capability Block II Development Drop Tests.

In the continuing effort to reduce costs while still maintaining a balanced and viable program, ASPO Manager George M. Low recommended to NASA Hq. that CSM 102 be deleted from the manned flight program. He estimated total savings at $25.5 million (excluding cost of refurbishment after the current ground test program). In addition, he said, during the static structural test program at North American Rockwell, CSM 102 would be subjected to loads that would compromise structural integrity of the vehicle for manned flight.

On August 7, Low asked MSC's Director of Flight Operations Christopher C. Kraft, Jr., to look into the feasibility of a lunar orbit mission for Apollo 8 without carrying the LM. A mission with the LM looked as if it might slip until February or March 1969. The following day Low traveled to KSC for an AS-503 review, and from the work schedule it looked like a January 1969 launch. Additional Details: here....

NASA Associate Administrator for Manned Space Flight George E. Mueller reported to his superiors that launch preparations for the Apollo 7 mission were running ahead of schedule. Spacecraft 101 had been erected and mated with the launch vehicle on August 9. Additional Details: here....

NASA Resident ASPO Manager Wilbur H. Gray at Downey told Dale D. Myers, North American Rockwell CSM Manager, that NR quality coverage of spacecraft testing no longer provided NASA with confidence in test results and that NASA Quality Control would return to monitoring test activities in and from the ACE (acceptance checkout equipment) control room. Gray charged that North American had progressively backed away from contractually agreed steps of the November 30, 1967, Quality Program Plan, and that these actions had affected test readiness, testing, and trouble shooting to the point that test acceptance could not be accepted with any reasonable assurance. Gray said that - unless North American responded by immediate reinstatement of the procedures which, as a minimum, were those that worked satisfactorily on CSMs 103 and 104 - NASA formal acceptance of operational checkout procedures would be discontinued and contractual action initiated. An annotation to George Low from Kenneth S. Kleinknecht, MSC's CSM Manager, indicated the letter had been written with the concurrence and at the suggestion of Kleinknecht.

Myers replied: "I regret that NASA feels any lack of confidence in current test results. . . . For the past year, there has been a constant improvement program carried out in Test Quality Assurance to (1) perform quality evaluation and acceptance of test results in real time and (2) upgrade the test discipline to be consistent with good quality practice. I believe that this improvement program has been effective and is evidenced by the current efficiency of test and expedient manner in which test paper work is being closed out. While there is naturally some cost benefit experienced from the successful improvements, cost never has been placed as a criteria above quality. . . .

"Again, I want to emphasize that the CSM Program has not nor will not intentionally place cost ahead of quality. . . . The procedures which worked satisfactorily on CSM 103 and 104 are being improved to provide better test discipline and more effective Quality Assurance coverage. Test progress on CSM 106 to date indicates a greater test effectiveness and a greater confidence in test results than any previous CSM's." Additional Details: here....

MSC Director Robert R. Gilruth sent Eberhard F. M. Rees, MSFC Deputy Director, his "personal commendation" and appreciation for Rees's leadership of the Apollo Special Task Team and its efforts to bring the CSM program out of the difficult period early in 1967. The work of Rees and his group, said Gilruth, had made an outstanding contribution to the Apollo program and had given NASA management "a significantly higher level of technical confidence" that the Block II spacecraft could safely perform its mission. In addition, Gilruth noted, Rees's "diplomacy in interfacing with North American management also created a much better NASA-contractor relationship and mutual understanding of program technical requirements."

In preparation for the flight of Apollo 8, NASA and industry technicians at KSC placed CSM 103 atop the Saturn V launch vehicle. The launch escape system was installed the following day; and on October 9 the complete AS-503 space vehicle was rolled out of the Vehicle Assembly Building and moved to the launch pad, where launch preparations were resumed.

While the flight of Apollo 7 was still in progress, ASPO Manager George M. Low ordered that CSM 101 be returned to Downey as quickly as possible at the end of the mission to begin postflight testing as quickly as possible. Therefore, no public affairs showing of the spacecraft could be permitted.

ASPO Manager George M. Low apprised Program Director Samuel C. Phillips of MSC's plans for television cameras aboard remaining Apollo missions. With the exception of spacecraft 104 (scheduled for flight as Apollo 9), television cameras were to be flown in all CMs. Also, cameras would be included in all manned LMs (LM-3 through LM-14).

The CSM Flight Readiness Review Board convened at MSC. Martin L. Raines presented the Reliability and Quality Assurance assessment and pointed out the improvement in discrepancy reports between spacecraft 101, 103, and 104 and concluded that 104 was better than 103 and ready to fly. George M. Low noted that the CSM Review had been outstanding.

A radiation survey of CSM 107 was planned to determine if the radiation produced by onboard sources would be of a sufficient level to impair the effectiveness of proposed experiments to measure the natural radiation emitted from the lunar surface. The survey would be conducted at KSC by personnel from the Goddard Space Flight Center.

The spacecraft walk-down team, established by ASPO in July in an effort to stem the increased number of human errors found in flight hardware, made a walkaround inspection of CSM-110 (Apollo 14 hardware). Cooperation of North American Rockwell and the Resident Apollo Spacecraft Program Office was excellent during the preparation and implementation of the inspection. No significant discrepancies were found by the inspection team during the several hours of inspection.

Ground rules for service module design and integration, established during recent changes in the lunar orbital science program, were reported. The Apollo LM experiment hardware would be installed and tested at KSC. A single scientific instrument module configuration was being proposed for Apollo 16-19 with modification kits developed, as required, to install Apollo 18 and Apollo 19 experiments. An expanded Apollo LM data system would be available for Apollo 16 (spacecraft 112).

NASA Deputy Administrator George M. Low and Associate Administrator for Manned Space Flight Dale D. Myers met and decided there was no foreseeable mission for CSMs 115 and 115a; funds would not be authorized for any work on these spacecraft; and skills would not be retained specifically to work on them.