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Apollo OWS + ATM
Apollo OWS + ATM

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Other Designations: Apollo Telescope Mount. Class: Manned. Type: Space Station. Nation: USA.

The Apollo Telescope Mount began as a solar telescope built into the spaceframe of an Apollo lunar module. Initially it was to be either fre-flying (operated by a visitng crew in an Apollo CSM) or launched separately and docked to a Saturn S-IVB orbital workshop. Over many years it evolved into a piece of hardware unrelated to the Apollo LM and integrated into the Skylab space station.


Apollo ATM Chronology

11 February 1966 MSFC submitted its response to the call from Headquarters for project management proposals for the Apollo telescope mount (ATM).

The plan summarized Marshall's developmental work on ATM-type systems so far and contained specific technical and managerial concepts for implementing the ATM project. Of all its inherent strengths and capabilities, the Center emphasized the talents concentrated in the Research Projects Laboratory under Ernst Stuhlinger, the scientific arm of the Center.

11 March 1966 Summary of NASA's total agency-wide AAP effort.

At Headquarters, the directors of the program offices presented to Deputy Administrator Robert C. Seamans, Jr., and members of the Administrator's top staff a joint briefing and summary of NASA's total agency-wide AAP effort. In reviewing their presentation, Seamans emphasized three cardinal tenets regarding AAP planning: (1) The Apollo lunar landing remained the top priority and must not be compromised by any AAP activity. (2) All changes to any Apollo hardware for AAP missions had to be approved personally by either the Administrator or Seamans. Consequently, all mission planning had to be precise and definite and would be referred to Webb or Seamans for action or approval. All procurement actions would be handled in the same fashion. (3) The directors were to devise 'a clear and defensible rationale' for MP missions. Seamans reported to Administrator James E. Webb the basic findings of the 11 March review: Largely because of limited resources, the pacing item in AAP was selection and development of experiments and packages to meet the earliest possible flight dates. (Although many possible experiments were being studied, only two minor AAP experiments so far had actually been committed to development. Also, some alternatives, such as use of Gemini and Apollo experiments and inhouse development of experiment packages, had been examined with an eye toward early experiment availability.) Three leading candidates existed for alternate AAP missions: (1) an extensive lunar mapping program (beyond the needs of Apollo); (2) adaptation of lunar mapping equipment for Earth survey (though 'serious interagency problems' had to be resolved before such a mission could be planned in detail); and (3) the ATM which, because of its scientific value and compatibility with the basic Apollo system, had received top priority for definition and development by the Office of Space Science and Applications (however, serious fiscal problems remained in light of the ATM's estimated total cost of about $69 million).

17 March 1966 Approval of the ATM project.

Homer E. Newell, Associate Administrator for Space Science and Applications, asked for approval of the ATM project from Deputy Administrator Robert C. Seamans, Jr. The ATM, Newell explained, was based on an engineering and definition study effort completed 1 April by Ball Brothers Research Corporation, as well as evaluation of the concept by four NASA Field Centers-LaRC, Goddard Space Flight Center (GSFC), MSFC, and MSC. The Ball Brothers Research Corporation study had been let in September 1965, said Newell, to determine means of providing an accurate pointing capability for high-resolution solar- oriented telescopes aboard an Apollo spacecraft. Further impetus to ATM had come from the agency's cancellation of the Advanced Orbiting Solar Observatory at the end of 1965. The ATM, he said, provided the means to obtain high-resolution data about the Sun during periods of maximum solar activity and served as a basis for evaluating ability to operate as an essential element within a complete manned space science system. The need for quick project approval and hardware development had been recognized by all participating parties, Newell explained, and Goddard Space Flight Center, MSFC, and MSC had all expressed 'deep interest and desire' to manage the project. However, after review within his office, he had decided to select Goddard as the most suitable location for development of the ATM. Accordingly, he asked Seamans to approve the project development plan.

09 April 1966 Cost and schedule estimates for MSFC to integrate the ATM with the LEM.

In response to a request from Deputy Administrator Robert C. Seamans, Jr., Saturn/Apollo Applications Deputy Director John H. Disher asked Jerry McCall, MSFC' Deputy Director for Research and Development Operations, to prepare cost and schedule estimates for 'MSFC to integrate the ATM with the LEM. This request stemmed from a desire by the Office of Space Science and Applications (OSSA) to acquire ATM experiment data during upcoming periods of maximum solar activity. Disher listed guidelines for the MSFC estimates: OSSA-desired flight dates were April 1968, February 1969, and February 1970. Goddard Space Flight Center would be responsible for development of experiments aboard the ATM, as well as for the mounting structure and thermal provisions. MSFC would be responsible for development of modification kits to convert all Apollo lunar-landing-configured LEM to an AAP laboratory configuration (including provisions for reuse after three to six mouths storage in orbit); for development of interface modification kits needed to integrate the ATM and its experiments with the AAP LEM laboratory; and for installation of the modification kits and the ATM system in the LEM at KSC prior to checkout and launch. In addition, Disher told McCall that MSFC should examine two approaches to ATM LEM integration: (1) gimbal mounted and (2) hard mounted with provisions for momentum transfer for fine pointing control.

22 April 1966 Development competition for the ATM delayed until the AAP funding picture for the next two fiscal years became clearer. Program: OWS.

NASA Deputy Director Robert C. Seamans, Jr., told Associate Administrator for Space Science and Applications Homer E. Newell that he had no choice but to delay initiation of development competition on the ATM until the AAP funding picture for the next two fiscal years became clearer. Because he had been unable to identify any source for the funds that would be required for the project during Fiscal Year 1967, Seamans said, 'I am extremely reluctant to start a competition in industry at a time when we cannot see our way clear to proceeding in a timely fashion.' On the other hand, he said he recognized Newell's deep interest in the ATM project and its scientific value and he was ready to proceed with advanced study work. Accordingly, he said he had signed the sole source award to Ball Brothers Research Corporation to study adapting the ATM for automatic observations in orbit beyond the basic 14-day manned mission and to study adapting the ATM to the Apollo lunar module (LM) for extended manned operations. Seamans expressed his own conviction that, to meet the objectives of the AAP mission at the earliest possible time, it would be best to mount the ATM directly on the Apollo command and service modules. If the present fiscal problem precluded such an arrangement, he told Newell, the agency would then be in a better position at a later date to decide whether the ATM should be included as part of the LM or whether some alternate approach should be used.

10 June 1966 Renewed request for approval of ATM development.

Associate Administrator for Space Science and Applications Homer E. Newell renewed his request for approval of ATM development to Deputy Administrator Robert C. Seamans, Jr. (See 17 March 1966). Newell repeated that detailed studies in house and under contract had established the feasibility of an ATM for conducting high-resolution observations of the Sun. He pointed out that a formal ATM organization had been created at Goddard Space Flight Center with over 30 people working full time on the project, and that they had prepared detailed scientific, technical, and management plans and were ready to begin the project immediately . Newell emphasized the importance of the ATM to the overall NASA solar physics program. Cancellation of the Advanced Orbiting Solar Observatory project, he said, left the Orbiting Solar Observation as the only approved program devoted to solar physics and that spacecraft did not have the technical capability to carry out the high-resolution studies so urgently needed. Newell pleaded for project approval and assignment of necessary funds to his office so that the ATM could be completed in time for a planned launch in 1969, the next period of maximum solar activity.

11 July 1966 NASA leaders make several significant program decisions affecting AAP and post-Apollo development planning.

Meeting at Headquarters, Deputy Administrator Robert C. Seamans, Jr., Associate Administrator for Manned Space Flight George E. Mueller, and Associate Administrator for Space Science and Applications Homer E. Newell made several significant program decisions affecting AAP and post-Apollo development planning in general: MSFC would be the lead Center for developing the ATM and would be responsible for all astronomy experiments. MSFC would be the lead Center for 'lunar engineering'-i.e., design and development of lunar exploration vehicles (including surface modules, supply trucks, and roving vehicles). MSC would have responsibility for Earth resources and lunar scientific experiments.

13 July 1966 NASA announced that project management responsibility for the ATM had been assigned to MSFC.

Under the agency's 'phased project planning,' any decision to begin ATM hardware development must await preliminary design study and evaluation at Marshall. But as conceived at this stage, the ATM would comprise several high-resolution solar telescopes attached to the Apollo spacecraft, to be operated by scientist-astronauts. Subsequently, ATM experiments contracts also were transferred from Goddard Space Flight Center to Huntsville.

19 July 1966 Development responsibility for the ATM project.

Following the decision to assign development responsibility for the ATM project to MSFC the manned space flight organization had concentrated its efforts on selecting the best location for the ATM within the Apollo spacecraft. Following the decision of Deputy Administrator Robert C. Seamans, Jr., to assign development responsibility for the ATM project to MSFC (see 11 July 1966), the manned space flight organization had concentrated its efforts on selecting the best location for the ATM within the Apollo spacecraft. Associate Administrator for Manned Space Flight George E. Mueller informed Seamans of their recommendation and requested his approval that the ATM be mounted within the LM. Mueller cited the design tradeoffs that led to this recommendation, the foremost being that the LM-mounted ATM, modified for storage and reuse in orbit, offered the greatest potential for meeting ATM performance requirements and experiment objectives, including the possibility of manned operation while detached from the CSM and thus free from external disturbances during fine pointing operations. (Other possible installation locations considered but rejected were an empty bay of the service module; a specially built rack for the ATM that would be launched inside the adapter section where the LM normally rested; and inside the spent-stage experiment support module.) Mueller stated that the LM-mounted ATM could be accomplished with programmed funds using MSFC in-house effort. Also, the system would include use of the LaRC-developed control moment gyro system for fine pointing control.

22 July 1966 George M. Low summarized MSC's thinking regarding proper location of the ATM with the AAP payload configuration.

Low affirmed Houston's approval of the recent assignment of total responsibility for the ATM to MSFC (an assignment that MSC had supported from the outset). The most important task now was to 'get on with the ATM in a most expeditious manner so that we can demonstrate once and for all that there is a major place for science and applications in manned space flight.' Further, Low said, getting on with the job meant 'making Marshall's job as simple and as straightforward as possible.' Because of extremely complex technical and managerial interfaces, the benefits of total systems responsibility at MSFC would be lost if the ATM were mounted on an Apollo LM. 'We frankly don't believe that the job can be done in this manner in any reasonable length of time,' he said. For much the same reasons, MSC also withdrew earlier recommendations that the ATM could be located in a sector of the service module or in the spent-stage experiment support module. Rather, he urged that the ATM be integrated into a self-contained rack; fitted into the adapter area and launched aboard a single vehicle along with the CSM. Low cited a number of specific objections to Headquarters' recommendation that the ATM be in the LM, even though the approach was technically feasible and offered several important advantages. Nonetheless, he repeated his view that operational factors, technical and managerial interfaces, and cost and schedule considerations all favored a rack-mounted approach. Crew safety factors alone were ample justification for such an approach, and he urged that Headquarters and MSFC proceed with such a design at the earliest possible date.

25 July 1966 Choice of location for the ATM narrowed down either to the LM ascent stage or to a specially designed rack structure completely supplanting the LM. Program: OWS.

John H. Disher, Saturn/Apollo Applications Deputy Director, advised his Systems Engineering Director that, on the basis of studies and review within both the OMSF and the OSSA, the choice of location for the ATM had been narrowed down either to the LM ascent stage (with a 'half rack' in place of the descent stage) or to a specially designed rack structure completely supplanting the LM. Disher requested additional information on both of these approaches to help in making final recommendations: (1) A comparison of command and service modules interfaces for the two concepts. (2) An analysis of interfaces between the LM rack and the ascent stage. (3) Descriptions of the subsystem installations for both the LM ATM and rack ATM.

02 August 1966 Mueller requestd approval of the preliminary AAP project development plan. Program: OWS.

George E. Mueller, Associate Administrator for Manned Space Flight, advised Robert C. Seamans, Jr., of progress toward selecting the proper location of the ATM with the AAP payload cluster and requested his approval of the preliminary project development plan. Mueller. urged proceeding immediately with the project based upon mounting the ATM on a rack structure that would (1) either supplant the descent stage of the LM (thus using the LM ascent stage for mounting experiment consoles and for supporting the crew during periods of observation) or (2) attach directly to the Apollo CSM. Mueller recommended beginning development work on the ATM project immediately, rather than deferring such action until the end of the year, in order to ensure flight readiness during the 1968-1969 period of maximum solar activity. Also, Mueller strongly supported Seamans' suggestion that much in-house effort and manpower at MSFC could be brought to bear on the ATM development program. Indeed, Mueller stated that such a course was essential to successful prosecution of the ATM project within available resources, even though several important industrial contracts for ATM components were still necessary.

29 August 1966 Approval to proceed with development and procurement actions to conduct one AAP ATM flight on missions 211/212. Program: OWS.

NASA Deputy Administrator Robert C. Seamans, Jr., notified George E. Mueller of approval to proceed with development and procurement actions to conduct one AAP ATM flight on missions 211/212 (as an alternate to the basic Apollo mission assigned to those two vehicles). Since only one ATM flight was thus far approved, Seamans emphasized the importance of focusing all project effort on meeting the existing SA 211/212 schedule. Seamans asked that he be kept fully informed of all major decisions during the system definition phase of the ATM project. He cited a number of points of particular interest: the design concept for the ATM and its rationale; experiments planned for the mission (especially on the assumption of a single ATM flight); operational concepts; procurement phasing with the option for a follow-on ATM if resources permitted; organizational, procurement, and management approaches for the mission; and schedule options available if SA 211 and 212 became available for an alternate ATM mission.

02 November 1966 Mission planning for AAP flights 209 through 212. Program: OWS.

After intensive effort by AAP groups at MSFC and MSC on the ATM and AAP mission planning for Flights 209 through 212, George E. Mueller told the two Center Directors that he now had ample information for a 'reasonable plan' to proceed with AAP. First, Mueller stated that the Orbital Workshop mission could best achieve AAP objectives by launching the complete airlock, Workshop, and multiple docking adapter unmanned into a one-year orbit, with activation to be accomplished by a separately launched crew. The first two AAP missions, said Mueller, would thus provide a three-man, 28-day flight and, at the same time, would establish a large clustered space configuration for use during subsequent missions. Secondly, Mueller posited that the ATM to be developed by MSFC could readily be integrated into an LM ascent stage and could reasonably be scheduled for launch during 1968. He cited the possibility that, by eliminating some equipment from the LM, the complete CSM-LM-ATM vehicle could be launched by a single booster. However, Mueller stated his belief that the correct approach should retain those LM subsystems required to operate the vehicle in a tethered mode, even though normal operation might call for the LM/ATM to be docked to either the Workshop or the CSM. Further, Mueller expressed real concern regarding the likelihood of significant weight growths in the ATM systems. For this reason he favored separate launch of the LM/ATM combination. Mueller planned to present AAP planning along these lines during discussions over the next several days with Administrator James E. Webb and the Director of the Budget regarding NASA's planning for manned space flight in the post-Apollo era.

05 November 1966 Lunar module ascent stage/half-rack Apollo telescope mount (LM/ATM) the baseline configuration for the ATM. Program: OWS.

George E. Mueller, Associate Administrator for Manned Space Flight, recommended to Robert C. Seamans, Jr., the lunar module ascent stage/half-rack Apollo telescope mount (LM/ATM) as the baseline configuration for development of the ATM. Mueller explained that a number of 'desirable characteristics' had been examined in comparing the LM ATM with its chief rival, a CSM rack/ ATM: (1) achievement of maximum solar data (through ease of operation, ability to repair, maintain, and reuse, and the capability of adding new instruments on subsequent missions); (2) maximum employment of man's capabilities for orbital astronomy (including pointing, film retrieval, repair and maintenance, and inflight analysis of solar data); (3) modes of manned operations (docked with the Orbital Workshop and separated from the cluster via a tether); (4) minimum cost consistent with accomplishing mission objectives; and (5) highest assurance of achieving program schedules. Comparison studies had shown that both the rack ATM and the LM/ATM should use the Langley-developed control moment gyro system for fine pointing control and that both configurations required a sizable volume to allow crew access to instruments and controls. The rack/ATM concept, Mueller told Seamans, was attractive primarily because of its simplicity. However, the vehicle could not be operated at a distance from the CSM to minimize contamination or motion disturbances (items of particular concern to ATM experimenters). On the other hand, the LM/ATM offered the greatest flexibility for meeting ATM requirements without any impact on the CSM. It could normally be operated while docked to either the CSM or the Workshop or, if experiment requirements so dictated, be either tethered or in free flight. This latter capability was especially valuable, Mueller explained, because it afforded a method of evaluating the range of modes for operating future manned orbiting telescopes and would permit early determination of the most desirable approach. (Mueller had recommended to Seamans approval of the ATM project some three months earlier and Seamans had given his okay shortly thereafter .)

28 November 1966 NASA announced selection of Bendix Corporation's Eclipse Pioneer Division to negotiate a contract for development and production of a pointing control system for the ATM. Program: OWS.

The work, covering three flight units at an estimated cost of $6.9 million, was directed by MSFC. The pointing system, one of several flight systems to be developed for the ATM program, was based on design of a control moment gyro that Bendix was already developing for Langley.

05 December 1966 NASA Hq issued a schedule which introduced the cluster concept into the AAP design. The cluster concept consisted of a Workshop launch following a manned CSM launch. Program: OWS. Launch Vehicle: Saturn IB, Saturn V.

Six months later, a LM/ATM launch would follow a second manned flight. The LM/ATM would rendezvous and dock to the cluster. The first Workshop launch was scheduled for June 1968. As opposed to the habitable OWS and cluster concept which projected a much more complex program, the S-IVB SSESM had been a comparatively simple mission requiring no rendezvous and docking and no habitation equipment. A major similarity between the old S-IVB/SSESM concept and the cluster concept was use of the S-IVB stage to put the payload into orbit before passivation and pressurization of the stage's hydrogen tanks. The new cluster concept embodied the major step of making the Saturn IVB habitable in orbit, incorporating a two-gas atmosphere (oxygen and nitrogen) and a 'shirt- sleeve' environment. The OWS would contain crew quarters in the S IVB hydrogen tank (two floors and walls installed on the ground), which would be modified by Douglas Aircraft Company under MSFC management; an airlock module (previously called the SSESM) attached to the OWS, which would be built by McDonnell Aircraft Corporation under MSC management; and a multiple docking adapter (MDA), which would contain five docking ports permitting up to five modules to be docked to the Workshop at any one time. The MDA would also house most OWS astronaut habitability equipment and many experiments. The schedule called for 22 Saturn IB and 15 Saturn V launches. Two of the Saturn IBs would be launched a day apart-one manned, the other unmanned. Flights utilizing two Saturn V Workshops and four LM ATM missions were also scheduled.

16 December 1966 MSFC awarded a contract to Bendix Corporation to design and develop control moment gyros to stabilize the attitude of the ATM in orbit.

01 February 1967 Scientist astronauts participating in the ATM program to be given an opportunity to visit a number of leading astronomical observatories in the country.

Despite the fact that crew assignments for the ATM flight had not yet been made, Saturn/Apollo Applications Program Director Charles W. Mathews recommended to MSC AAP Manager Robert F. Thompson that scientist astronauts who had been participating in the ATM program at Huntsville be given an opportunity to visit a number of leading astronomical observatories in the country. In this manner, Mathews said, potential crew members could derive a better understanding of the equipment being employed, operation techniques being used, and the nature and types of observations being made.

20 March 1967 MSFC awarded Bendix Corporation a contract for development and production of the ATM pointing control system.

The control system would enable astronauts to point a telescope at selected regions of the Sun during periods of maximum solar flare activity. MSFC had earlier awarded American Optical Company a contract to build a dynamic simulator for use in developing the pointing control system.

24 March 1967 Modified OWS electrical power system.

In accordance with design discussions and decisions reached during discussions several days earlier, AAP Director Charles W. Mathews directed Center AAP Managers to implement a modified OWS electrical power system. Because of increased electrical power requirements resulting from making the OWS a habitable laboratory, solar cell arrays were added to each side of the S IVB stage to provide most of the electrical power used during AAP cluster operation. (Before this design shift, the CSM's fuel cells had been considered the primary source of power.) In addition, the ATM would still have its own solar array panels and power system.

01 May 1967 Both MSFC and MSC recognized the existence of a potential interference of contaminant materials in the vicinity of manned spacecraft with the optical equipment on the ATM.

It was also recognized that certain building materials that might create contaminate problems needed to be avoided in the ATM structure. A considerable activity concerning this contamination problem had already developed at MSFC, MSC, NASA OSSA, some contractor plants, and the ATM Principal Investigators.

05 May 1967 Revised Apollo and AAP-integrated program plan shows CSM would be available to support the first four AAP launches. Program: OWS.

Some significant features of a revised Apollo and AAP-integrated program plan were: CSM would be available to support the first four AAP launches; AAP-1/ AAP-2 in early 1969 were to accomplish OWS objectives; AAP-3/AAP-4 in mid-1969 were to accomplish the 56-day ATM objectives in conjunction with reuse of the OWS. Two additional AAP flights were planned for 1969 to revisit the OWS and the ATM using refurbished command modules flown initially on Earth-orbit Apollo flights in 1968. AAP missions planned for low Earth orbit during 1970 would utilize two dual launches (one manned CSM and one unmanned experiment module per dual launch) and two single-launch, long-duration CSM to establish and maintain near- continuous operation of the OWS cluster and a second ATM.

24 May 1967 The ATM would offer a unique combination of several important advantages over previous manned orbital astronomical experiments, ground-based observatories, and unmanned orbital observatories.

It would be the first U.S. manned mission with a primary goal of recovering scientific data. The ability to observe the Sun in previously inaccessible but important regions of the electromagnetic spectrum, to observe the details on the solar disk and in the corona for nearly two solar rotations, and to react rapidly to unpredictable and unexpected occurrences with instruments of high data acquisition capabilities would be an unprecedented combination of opportunities available only to the crewman operating the ATM. However, it was essential to recognize that the crewman's ability to observe, exercise judgment, and efficiently conduct the routine experiment tasks, as well as to rapidly respond to unpredictable phenomena would be contingent upon the existence of displays in the proper wavelength regions with sufficient resolution to observe the important features on the solar disk. Also necessary would be controls which would combine simplicity and versatility to facilitate equipment setup for data acquisition.

19 June 1967 MSFC and MSC representatives met with Principal Investigators at MSC where detailed briefings on the ATM were held.

This was the final briefing of a series on ATM systems and experiments.

05 July 1967 MSFC and MSC personnel met at MSC to resolve action items from a Headquarters test meeting held on 30 March.

The action items involved the LM/ATM thermal vacuum test program. General agreement was reached on test configuration, with MSC supporting the MSFC position that a thermal vacuum test was necessary on the ATM flight unit. MSC agreed to conduct a chamber contamination test with jointly agreed upon procedures. MSC, 'AAPO Weekly Activity Report,' 5 July 1967.

11 July 1967 Increased activity and interest in the ATM project created the necessity for conducting ATM monthly project reviews in the Office of Manned Space Flight.

MSFC provided the principal inputs on such aspects as schedules, funding, and technical performance. Material covered progress achieved during the month, current problems, and actions taken.

26 July 1967 Martin Marietta contract for payload integration in space vehicles for the AAP. Program: OWS.

NASA selected the Martin Marietta Corporation, Denver Division, for negotiation of a 27-month contract for payload integration of experiments and experiments support equipment in space vehicles for the AAP. Initial work of the contractor involved the OWS and ATM at MSFC; meteorological and Earth resources payloads at MSC; and test integration planning and support for launch operations at KSC.

23 August 1967 The ATM required a closely controlled environment during manufacture, quality checkout, and flight checkout activities.

To ensure the required control of cleanliness, temperature, and humidity, two buildings were required at MSFC-one for the manufacturing process, the other for quality checkout. An environmentally controlled area was also required at KSC for flight checkout of the ATM.

26 October 1967 An active cooling system (fluid circulation) was incorporated into the ATM thermal system to meet temperature control requirements.

An active cooling system (fluid circulation) was incorporated into the ATM thermal system to meet temperature control requirements

01 December 1967 NASA presented the ATM program to the Astronomy Missions Board at Cambridge, Massachusetts. Considerable interest was shown by the Board regarding crew participation in the ATM mission.

The Board recommended an early crew assignment for ATM, so that adequate training in solar physics could be provided, and also recommended that scientist astronauts be assigned as members of the ATM flight crew.

05 January 1968 NASA lunar exploration program developed for the period from the first lunar landing to the mid-1970s. Program: Apollo X.

A lunar exploration program had been developed which would cover the period from the first lunar landing to the mid-1970s. The program would be divided into four phases: (1) An Apollo phase employing Apollo hardware. (2) A lunar exploration phase untilizing an extended LM with increased landed payload weight and staytime capability. (3) A lunar orbital survey and exploration phase using the AAP-1A carrier or the LM/ATM to mount remote sensors and photographic equipment on a manned polar orbit mission. (4) A lunar surface rendezvous and exploration phase which would use a modified LM in an unmanned landing to provide increased scientific payload and expendables necessary to extend an accompanying manned LM mission to two weeks duration.

05 February 1968 Saturn V OWS study teams were examining a range of concepts in two distinct categories, OWS B and OWS C. Program: OWS.

OWS B would be a relatively simple, generic evolution from the Saturn I OWS being developed for the first AAP missions. It would retain the basic elements of the Saturn I OWS but would incorporate the ATM solar astronomy payload as an integral part of the OWS. Other modifications to improve overall effectiveness would be incorporated where this could be achieved with small increments of funds or time. OWS C would be a more advanced concept in the evolution toward a flexible operational system for sustained operations in Earth orbit. It would provide living and working quarters for a crew of nine and would be operable for two or more years.

12 February 1968 Objectives of the AAP-3/AAP-4 mission outlined. Program: OWS.

Objectives of the AAP-3/AAP-4 mission were to Obtain scientific data on the physical characteristics of the Sun through observations of various portions of the electromagnetic spectrum made with ATM experiments.. Obtain engineering data from the operation of the ATM attached to a LM ascent stage to support development of an advanced manned orbital observatory. Demonstrate hard dock of the LM/ATM to the MDA of the Saturn I OWS left in orbit from the AAP 1 /AAP-2 mission. Determine feasibility of reactivating and operating a Saturn I OWS as a habitable space structure for a period of up to 56 days from the AAP-3 launch date through evaluation of the CSM/S- IVB/AM/MDA.

26 February 1968 A management review of the pointing system for the ATM was held with Perkin Elmer Corporation. Conceptual design was completed and approved by MSFC.

In addition, the preliminary requirements review for the H-Alpha telescope and pointing system was satisfactorily completed by MSC.

29 February 1968 An evaluation and selection committee was formed to review the suitability of candidate chambers for ATM thermal vacuum testing.

The committee, composed of members from the OMSF Apollo Applications Program Office, MSFC, MSC, Goddard Space Flight Center, and the Jet Propulsion Laboratory, would evaluate chambers located at MSC, Arnold Engineering Development Center, The Boeing Company, and General Electric Company, in terms of availability, schedules, capability, modification requirements, contamination control, cost, and logistics.

09 March 1968 The ATM Principal Investigators presented the status of their experiments at Ball Brothers Research Corporation in Boulder, Colorado.

They reported good progress in the development of their instruments and presented material to support their assessment that delivery would be on schedule. They also stressed the importance of flying a mission as early as possible during a period of high solar activity.

18 March 1968 A task team was established to review the requirements and establish a new baseline for the LM and the ATM with the objective of reducing costs and operational complexity.

The team was composed of senior members from the OMSF, MSC, MSFC, The Martin Company, and Grumman.

25 May 1968 A LM/ATM Evaluation Board, established to make an in-depth review of the planned LM/ATM module configuration and mission, issued its final report.

The Board review concentrated on the operational and programmatic aspects related to use of the LM with the ATM. At a meeting held on 9 March, the ATM experiment status was the subject of discussion. Principal Investigators and the MSFC ATM Program Office representatives summarized progress on each experiment and on the total ATM package. At meetings held on 15 16 March, presentations were made by MSC and MSFC. MSC stressed the operational complexities of the dual-rendezvous, dualdocking capability of the LM, extravehicular activity, crew training, and mission critical sequencing. MSFC stressed the desirability of the cluster mission and, while recognizing the problems of dual rendezvous, suggested that the system and mission as configured was the best possible choice.

09 August 1968 ATM film and camera storage during launch, throughout the mission, and during reentry was reviewed.

North American representatives covered the command module's capability for film return, and Grumman representatives discussed the lunar module's crew provision storage. Principal Investigators and MSFC ATM personnel attended the presentation.

23 September 1968 A preliminary design review for the ATM was held at MSFC.

Working groups composed of scientists, engineers, and astronauts covered specific areas such as pointing control, electrical and electronic support equipment, mission operations requirements, mechanical and thermal considerations, instrumentation, communications, control and display equipment, crew station, experiments, and quality and reliability during testing and manufacture.

28 January 1969 Development tests to verify the design concept of the chain drive mechanisms of the ATM solar array system were completed.

Preliminary data and operation were very promising. This hardware would be utilized in assembly of a complete solar array to be used for deployment testing.

04 February 1969 A meeting of the ATM Contamination Working Group was held at KSC. Representatives present were from NASA Hq, KSC, MSC, and MSFC.

Experiment Principal Investigators also attended. Items covered included real-time contamination monitoring during thermal vacuum testing, thermal vacuum test plans, optical degradation from vacuum chamber operations, and cluster effluent studies. Several of the Principal Investigators expressed a desire for real- time contamination monitoring during thermal vacuum tests of the ATM. The Naval Research Laboratory was trying to develop a monitor for the ultraviolet region and was planning to submit an engineering change proposal to provide an ultraviolet source for the tests. This would allow them to operate their instruments and obtain data on their efficiency during such tests.

18 February 1969 An early test model of the ATM control computer was delivered by Bendix Corporation to MSFC where it was undergoing performance tests.

This was a preproduction unit and did not include all the functions that would be in the flight version. The first flight unit was scheduled for delivery in September 1969.

04 March 1969 A series of ATM extravehicular activity neutral buoyancy tests were performed at MSFC. Astronauts participated in both scuba gear and pressurized space suits.

Purpose of the tests was to evaluate the performance and procedures for moving film cassettes to the two ATM work stations and to perform some of the tasks required at these stations. Recommendations were made for the improvement of most of the features evaluated. As a result of the tests, equipment and procedures modifications were made.

01 April 1969 The ATM would be a manned solar observatory making measurements of the Sun by telescopes and instruments above the Earth's atmosphere. Program: OWS.

The instruments would obtain data on the transitions occurring in elements ionized in the vicinity of the Sun's surface data contained in the ultraviolet and x-ray spectrum absorbed by the Earth's atmosphere. Orbiting telescopes would also observe flares and regions of the corona hidden to Earth-bound telescopes or covered by scattered light.

07 April 1969 A small film canister, designed and fabricated at MSFC, was delivered to KSC for flight test on Apollo 10.

The canister, packed with a variety of photographic film, would obtain information on the sensitivity of film to the thermal, pressure, and radiation environment of space, in part equivalent to those which would be experienced by the ATM in flight. The test would also complement ground testing and theoretical analyses that were conducted to evaluate potential film fogging in a space environment.

15 April 1969 A meeting was held at MSFC with representatives of the camera manufacturers, North American, Grumman, and MSFC to review ATM camera stowage and handling and the CSM and LM stowage.

The following areas were discussed and assigned for further study: environment (thermal, shock, and vibration); interface control documents for the cameras and carriers; LM and CM stowage volume and weight limitations and their effect on camera configuration; and camera extravehicular activities.

21 May 1969 Saturn V "dry" Workshop decision. Program: Skylab. Launch Vehicle: Saturn IB, Saturn V.

Gilruth and Von Braun support decision to fly a complete integrated solution on a single Saturn V launch. Additional Details: Saturn V "dry" Workshop decision..

22 May 1969 KSC hosted a meeting of the AAP Principal Investigators to familiarize them with KSC facilities and equipment.

Items covered included experiment timelining, ATM test and checkout, KSC AAP- 4 vehicle flow plans, and quick-look data systems.

10 June 1969 The critical design review of the ATM control computer was held at MSFC. All submodules of the flight module control computer, with one exception, were reported as designed.

An engineering model control computer was available for examination at the review.

01 July 1969 A study was conducted to determine the feasibility of providing an artificial gravity operating mode for a second OWS. Program: Skylab.

Study results indicated there were several areas of the OWS that would require unique configuration characteristics. Among the areas of concern were antenna location and coverage; CSM/MDA docking interface strength; reaction control system characteristics, propellant consumption, and attitude control logic to maintain solar orientation in the face of gravity gradient torques; ATM mounting and deployment provisions; and the ATM solar array structure.

18 July 1969 NASA Administrator Paine approved the shift from a "wet" to a "dry" Orbital Workshop for AAP. Program: Skylab. Launch Vehicle: Saturn IB, Saturn V.

NASA Administrator Thomas O. Paine approved the shift from a 'wet' to a 'dry' Orbital Workshop concept for AAP following a review presentation by program officials on the potential benefits of such a change. On 22 July, AAP Director William C. Schneider ordered program managers at the three Centers to implement the change, abandoning the idea of using a spent Saturn IB second stage for a Workshop and adopting the concept of a fully equipped 'dry' configuration-with the ATM integrated into the total payload-launched aboard a Saturn V. Additional Details: NASA Administrator Paine approved the shift from a "wet" to a "dry" Orbital Workshop for AAP..

22 July 1969 NASA formally announced the AAP project reorientation to the "dry" Workshop configuration-both the fully outfitted workshop and integrated ATM launched aboard a single Saturn V. Program: Skylab.

Program objectives for AAP remained unchanged, however. The schedule called for first launch in 1972. The Workshop would be placed in a circular orbit first. About a day later, the three-man crew would ride aboard a Saturn IB into orbit to link up with the Workshop-ATM cluster, thus beginning the manned portion of the mission.

29 July 1969 A critical design review was held on the two H-Alpha telescopes being provided for the ATM by Perkin-Elmer Corporation. Program: Skylab.

Representatives from NASA Hq, KSC, MSC, MSFC, Harvard College Observatory, and Naval Research Laboratory attended. Except for the mechanical reticle subsystem, a requirement recently added to the telescope system, the Perkin-Elmer design appeared sound. Only minor discrepancies were noted.

30 July 1969 MSFC was studying three options for the ATM pointing control system dry OWS attitude control.

Option one was basically the same ATM pointing control system as previously configured, with an additional digital computer; option two was an all-digital computer system; and option three was primarily digital, but retained portions of the analog computer for ATM experiment pointing control.

06 August 1969 A neutral buoyancy chamber exercise for the ATM was conducted at MSFC.

The purpose was to examine some extravehicular activity concepts under development to determine their validity for incorporation into the dry OWS configuration. Crewmen were somewhat constrained and uncomfortable because, while the suits were neutrally buoyant, crewmen inside the suits were not. The neutral buoyancy exercise was followed by an ATM extravehicular activity crew station engineering review. It consisted of a suited and unsuited walk through evaluation of the ATM film replacement work stations. Several modifications were recommended.

07 August 1969 MSFC awarded a contract to Martin Marietta for the fabrication, testing, and delivery of 15 Saturn V OWS rate gyro processors, a module test set, and the retrofit of 22 ATM rate gyro processors.

The rate gyro packages would fly on the OWS and would provide precise attitude control of the OWS cluster, including the ATM.

13 August 1969 Functional and environmental development tests were performed on the ATM H-Alpha telescope zoom lens, temperature control, and optical subsystems.

The zoom lens subsystem failed during vacuum testing and was being reworked. At a later date, the camera electronics subsystem would be subjected to temperature tests, and the mechanical reticle subsystem to thermal-vacuum and vibration tests.

29 August 1969 MSFC requested McDonnell Douglas and Martin Marietta to develop preliminary design and cost data on a number of OWS system elements that were previously planned for in-house development.

Among these were fixed payload shroud, oxygen, and nitrogen bottle installation; cooling of the ATM control and display; deletion of the scientific airlock; design and fabrication of the solar array system; installation of experiments; and MDA integration and checkout.

03 September 1969 A meeting was held at MSFC that provided the ATM Principal Investigators an opportunity to express their desires regarding experiment operation during unmanned periods of the ATM OWS mission.

AAP personnel from NASA Hq, MSC, and MSFC, as well as ATM Principal Investigators, attended. The investigators felt strongly that their early participation in program decisions that affected experiments would permit a much more effective experiment program without significant budget or schedule changes.

04 September 1969 The critical design review on the ATM charger battery regulator module was held with satisfactory results.

Numerous tests on the module components were conducted. An engineering prototype was undergoing thermal cycle, charge, and discharge test.

16 September 1969 The change in AAP from the wet to the dry OWS substantially improved the probability of mission success and crew safety.

Some of the hardware and operational improvements contributing to crew safety were increased payload capability, which would reduce risks from submarginal booster performance, launching the ATM as an integral part of the OWS, thus eliminating an extra launch that involved a complex and operationally difficult unmanned rendezvous and docking; standardizing the three manned launches, using proven software and training techniques, thereby reducing some of the risks associated with new operational phases and missions; and the powering down of the CSM to a quiescent state during the orbital period of operation, with a consequent reduction in wearout or limited-life failures.

17 September 1969 An ATM control moment gyro was subjected to thermal-vacuum, vibration, and electromagnetic interference development environmental testing.

Tests indicated that, with proper insulation, no major problems existed in the thermal-vacuum area. However, with the extended requirements for the OWS, command moment gyro actuator lifetime was a concern. In addition to converting to a wet lubricant system, Bendix Corporation and Battelle Memorial Institute, Columbus, Ohio, were asked to study other steps that might be taken to ensure a 300-day lifetime for the control moment gyro actuators.

23 September 1969 An AAP test planning meeting was held at KSC. Representatives from KSC, MSC, MSFC, and NASA Hq attended.

Purpose of the meeting was to review the status of factory acceptance test planning for all modules, the preliminary CSM interface test requirements at KSC, and the KSC planning pertinent to conducting AAP integrated module tests. Open issues that would require resolution included flight experiment delivery dates, flight ATM control and display availability for integration into the MDA and compatibility for integration into the MDA, and compatibility of flight and prototype ATM delivery dates to support KSC checkout and integrated module test need dates.

27 October 1969 An ATM program review was held at MSFC. ATM Principal Investigators and representatives from NASA Hq, MSC, and MSFC attended.

Among the areas discussed were unmanned operations, thermal control, operating lifetime, and availability of acceptance checkout equipment. A study was being conducted to identify the amount of thermal control required during inflight storage periods. In addition, life testing was being performed to determine capability for extending the operating lifetime of the ATM.

04 November 1969 Two Apollo ATM-related Aerobee rockets were launched from the White Sands Missile Range, New Mexico. Program: Skylab. Launch Vehicle: Aerobee.

The rockets achieved expected performance, solar pointing systems functioned properly, payloads were successfully recovered, and preliminary results appeared excellent. The information obtained by the rocket flights on solar emission intensity, filter performance, film response, and exposure time would be available in time to provide a useful and effective feedback into the ATM instruments development program.

02 December 1969 AAP cluster systems review at MSFC.

A review team representing NASA Hq, the three manned space flight Centers, the several prime contractors involved, and many of the Principal Investigators for experiments conducted the AAP cluster systems review at MSFC. Cluster hardware subjected to scrutiny included attitude control, thermal, instrumentation and communications, structural, electrical, and crew systems, as well as mission requirements and the overall system-level capability of the AAP cluster to meet those objectives. In one significant design decision, program officials decided to parallel the electrical power system of the ATM with the rest of the cluster through the airlock to increase overall reliability of the cluster's electrical power system.

15 December 1969 Because of stringent budget restrictions MSFC was requested to carefully scrutinize the ATM experiment and supporting systems requirements.

Because of stringent budget restrictions MSFC was requested to carefully scrutinize the ATM experiment and supporting systems requirements and eliminate any existing or proposed modifications that were not mandatory to the successful accomplishment of the scientific experiment objectives. Modifications which were not yet implemented would be carefully examined to determine: If the requirements matched the approved experiment objectives. If the requirements could be met without the change. If funding or development schedules would be impacted in an unfavorable. manner if changes were authorized. If alternate approaches could be taken to meet objectives of required changes with a less unfavorable impact on funding and schedules.

22 January 1970 Apollo Applications Program Managers met at MSFC and conducted a full review of the ATM status. Program: Skylab.

Among the items covered were the film vault design, film test program, subsystems status, module ground test program, quality and reliability, mission operations support to MSC, prototype refurbishment, project schedules, and funding.

04 February 1970 The recommendation was made that serious consideration be given to providing training in solar physics to the Skylab astronauts in the immediate future.

Purpose of the training would be to obtain maximum benefit from the ATM experiments by equipping the astronauts with a well-rounded knowledge of solar physics and the training required for them to become experienced solar observers.

09 February 1970 Manned Orbiting Laboratory environment conditioning units delivered.

With the termination of the Manned Orbiting Laboratory, the Air Force provided MSFC with three environment conditioning units capable of delivering fresh air into a small enclosed space at a desired temperature and humidity. The units would be used during bench checks and troubleshooting on the ATM experiments and the related ground support equipment during storage and the preinstallation period.

17 February 1970 A ground support equipment meeting was held at MSFC with representatives from NASA Hq, MSC, MSFC, McDonnell Douglas, and General Electric Company participating.

Purpose of the meeting was to establish lines of communication and to discuss test and checkout philosophies and responsibilities, ground support equipment status, and problems of common interest. On 18 February a similar meeting was held to discuss ground support equipment associated with the ATM project.

08 April 1970 An ATM crew station review was held at MSFC.

Results of the review included the following: MSFC would investigate ATM timing sources to satisfy the 16-mm Maurer control and display sequence camera timing and sequencing requirements. An improved layout of control and display circuit breaker panel was suggested by the crew. The impact of providing a display designed to show the crew that the ATM digital computer had accepted a console-initiated keyboard command was being assessed by MSFC.

26 May 1970 The ATM critical design review was completed, with the Critical Design Review Board meeting at MSFC.

This review gave formal approval to the ATM design.

03 June 1970 The ATM thermal systems unit was delivered to MSC from Marshall.

It was subjected to the temperature and vacuum extremes of a space environment in the MSC thermal vacuum chamber as part of the qualification program of the ATM.

16 July 1970 A meeting was held at NASA Hq to discuss unmanned ATM operations. ATM Principal Investigators and personnel from MSC, MSFC, KSC, and NASA Hq attended.

Following presentations by MSC and MSFC and statements by the investigators, a daily eight-hour unmanned operation of the ATM was baselined.

30 July 1970 Inter-Center agreement on the use and control of acceptance checkout equipment-spacecraft (ACE-S/C) for the checkout of the ATM.

Skylab Program Managers Thomas W. Morgan, KSC, Leland F. Belew, MSFC, and Kenneth S. Kleinknecht, MSC, approved an inter-Center agreement on the use and control of acceptance checkout equipment-spacecraft (ACE-S/C) for the checkout of the ATM at all locations and the AM downlink at KSC.

25 September 1970 MSFC modified the existing Skylab contract with Martin Marietta. The contract change covered ATM mission support at MSC and MSFC.

20 December 1970 The payload shroud test article was successfully tested at the Plum Brook Facility of Lewis Research Center.

The purpose of the payload shroud would be to cover and protect the ATM MDA, and top portion of the AM as Skylab was launched into an Earth orbit.

26 January 1971 An ATM experiments Principal Investigator meeting was held at Boulder, Colorado.

It was designed to ensure total agreement on experiment objectives, development, operations, and data analysis, as well as to ensure that crew and mission operations requirements would be met. Representatives of MSFC, MSC, and Martin Marietta attended the meeting. The scientists who proposed the six solar astronomy experiments also attended the meeting. An update of the proposed Martin Marietta facilities designed to support Skylab was presented The solar data from ground observatories needed to support mission operations were described by National Oceanic and Atmospheric Administration personnel, and their recommendations were agreed to, with the stipulation that additional data were needed. The ATM film study identified some problem areas to be resolved, such as temperature control and radiation protection for film.

15 March 1971 Skylab trainer meeting.

A Skylab trainer meeting with representatives from MSC and MSFC reviewed the delivery schedule for the major Skylab trainer modules and experiment trainers, the schedule for initial acceptance, and the training hardware acceptance data package requirements. Delivery dates were reviewed, and a delivery schedule established. It was agreed that MSC would develop a list of trainer hardware, identify trainer systems, and develop the trainer acceptance checkout procedures. The following Skylab training modules would be delivered to MSC: OWS one-g trainer; airlock one-g trainer; airlock zero-g trainer; airlock neutral buoyancy trainer; airlock; one-g support stand; neutral buoyancy deployment assembly; MDA trainer; ATM one-g trainer; ATM zero-g trainer; and ATM neutral buoyancy trainer.

16 June 1971 Capability to switch control of the Skylab vehicle back to the instrument unit.

John L. Disher, Deputy Director of the NASA Skylab Program, approved a configuration control board change which would provide the capability to switch control of the Skylab vehicle back to the instrument unit. John L. Disher, Deputy Director of the NASA Skylab Program, approved a configuration control board change which would provide the capability to switch control of the Skylab vehicle back to the instrument unit after the initial transfer to the Apollo telescope mount digital computer control. The current configuration would preclude a switchboard and prevent the use of the IU control system should problems arise during the first critical hours of active ATM DC control. Concern over the inability to make the switchback was constantly expressed by MSC because unexpected previously unidentifiable failures occurred during actual flight in every computing system used-e.g., lunar module guidance computer, command computer IU, real- time computer complex, and the Gemini computer.

17 June 1971 An optical efficiency problem was reported in the Naval Research Laboratory ATM flight instrument at Ball Brothers Research Corporation.

A failure analysis review attended by experts from Bausch & Lomb, Ft. Belvoir, Virginia, Goddard Space Flight Center, Naval Research Laboratory, and MSC concluded that failure was due to the 'Purple Plague,' an aluminum coating overcoating on gold. An alert would be released by Goddard for dissemination throughout NASA and the Air Force to preclude further use of this particular method of coating optics.

24 June 1971 A study indicated that if the Skylab airlock could not be used for a normal extravehicular activity, contingency modes were possible.

One would be a two-man EVA to the ATM using oxygen, water, and electrical umbilical connections in the structural transition section of the airlock. Another possibility would be a one-man EVA from the CM. Selection of a contingency EVA mode would depend on the failure that prevented the nominal operation.

25 June 1971 Authority to proceed on the Skylab calibration rocket program.

Authority to proceed on the calibration rocket program was given by NASA to determine the amount of degradation of Harvard College Observatory and Naval Research Laboratory experiment data to be expected during the Skylab mission. Degradation due to decrease in mirror reflectivity, changes in photographic film sensitivity, gamma and background fogging, and aging of filters and gratings could cause misinterpretation of the solar data. To improve data evaluation, sounding rocket launchings during the mission were proposed, to carry instruments similar to those in the ATM and calibrated to a known light source. These instruments would be pointed to some of the same solar areas as were the ATM and the returned data would be compared to the ATM data.

14 September 1971 An Apollo telescope mount final acceptance review for the ATM one-g and zero-g trainers was held at MSFC.

Representatives from MSC, MSFC, Martin Marietta, and Brown Engineering Company attended. The trainers were scheduled for shipment, with an arrival date at MSC of 12 October.

30 September 1971 Apollo telescope mount results from thermal/vacuum test performed September-December 1971.

Corrective measures were being incorporated into the Apollo telescope mount as a result of the prototype thermal/vacuum test being performed in the MSC Space Environmental Simulation Laboratory September-December 1971. A number of anomalies unidentified in previous component system or subsystem tests were identified. Unlocated, the anomalies could have had serious impacts on ATM orbital operations.

08 October 1971 Personnel and equipment from other countries were being utilized in the Skylab Program.

K. Pounds (United Kingdom), M. Oda (Japan), and Pande (India) were endorsed as ground-based observers in connection with the ATM. Proposals for participation in Earth resources were anticipated from Canada, Argentina, Chile, India, Iran, Japan, Thailand, Belgium, France, Germany, Greece, Switzerland, and the United Kingdom. Numerous small articles of equipment such as zippers and lenses were obtained from England, Switzerland, Germany, and Monaco. Cameras were obtained from Sweden and Japan. Glass for the multispectral photography window came from Japan. Rockets used for ATM calibration flights were obtained from Canada.

11 November 1971 An acceptance review of the ATM experiment training hardware was held at MSFC. MSC representatives participated in the review.

Following the review, the hardware was shipped to MSC for crew familiarization in preparation for a multiple docking adapter crew compartment fit and function review.

15 December 1971 The prototype of the Skylab ATM was returned to MSFC from MSC aboard the Super Guppy aircraft. Program: Skylab.

At MSFC, the ATM was placed in a clean room in the Quality and Reliability Assurance Laboratory for a system checkout. It would next undergo vibration testing in the Astronautics Laboratory and then would be refurbished to serve as a backup for the flight model. While at MSC, the ATM prototype, which was assembled at MSFC, had been subjected to space conditions in a large chamber used for testing the Apollo spacecraft.

13 January 1972 Leland F. Belew reported that the airlock module flight article systems tests were nearly completed. Program: Skylab.

The AM had been moved from the test area on 10 January to begin the mating operation with the ATM deployment assembly and the fixed airlock shroud. The multiple docking adapter had completed shell leakage tests and was undergoing radiator leakage tests. Special illumination tests and TV camera/video recorder tests began 10 January at McDonnell Douglas. Personnel from MSC, MSFC, and NASA Hq were observing the testing.

01 February 1972 MSFC and MSC completed a Memorandum of Agreement with the National Oceanic and Atmospheric Administration (NOAA) for support contracts for Skylab.

The contract would include both ATM and crew radiation monitoring support in the areas concerning the solar network and Mission Control Center Operations. ATM support performed by the National Oceanic and Atmospheric Administration as required by MSFC and MSC would be contracted for by MSC, with that Center providing the technical monitor for the contract and technical direction during the mission simulation and inflight operations phases. Requirements would include a variety of solar data on current solar conditions and predicted solar conditions. These data would ensure effective scheduling of ATM experiments and ATM data for Principal Investigators in the form of photographs, line drawings, etc., to support their detailed analyses of solar activity. The crew radiation monitoring support would be contracted by MSC, with all technical direction provided by the MSC technical monitor. These activities would include management and operation of facilities for acquisition and transmission of solar data for crew radiation monitoring during simulations and inflight operations; a 24-hour solar watch and photographic record; and monitoring of current and future radiation environments to provide an assessment of the biological effect on the flight crew.

03 February 1972 The Apollo telescope mount flight unit was being readied for a three-month, post-manufacturing checkout at MSFC. Program: Skylab.

The ATM would be moved in May from the Quality and Reliability Assurance Laboratory to the Astronautics Laboratory for vibration tests and would be delivered to MSC I June for thermal and vacuum tests. The ATM would be launched on the first Skylab mission in 1973.

18 February 1972 Vibration testing began on the Apollo telescope mount prototype at MSFC. After vibration testing, the prototype would be disassembled and refurbished. Program: Skylab.

It would then become the backup ATM flight unit.

11 May 1972 The Apollo telescope mount crew compartment fit and function review was conducted at MSFC. Skylab astronauts participated.

ATM flight cameras and film cassettes were checked during the review.

01 June 1972 Rising costs for the ATM experiments were attributed to a number of factors. Principal among these was the delay in launch time of over four and one-half years. Program: Skylab.

The ATM development began in 1965 and was scheduled for launch in 1968. The long delay in launch time meant that the Principal Investigators, their in-house staffs, and their contractors had to be supported for the additional four years. Other factors which contributed to the cost increase were new state-of-the art developments for which NASA or the Principal Investigators had no previous experience.

17 July 1972 Skylab vibration and acoustics test program completed.

A Skylab vibration and acoustics test program which began at MSC in January 1971 was completed. The 18-month test program was characterized by extreme complexity requiring highly innovative testing techniques. It was the first time that an extensive test operation was conducted with a computer-controlled system. All components of the Skylab payload assembly were involved in the test program. The complete assembly, as it would be at launch, underwent vibration and acoustic tests. Then the cone and shroud were removed, the ATM deployed, and the CSM joined to the MDA for tests with the assembly positioned as it would be in Earth orbit.

22 September 1972 The Skylab Apollo telescope mount arrived at the KSC skid strip aboard a Guppy aircraft. Program: Skylab.

The ATM, which had been at MSC since mid-July, was immediately moved to the Operations and Checkout Building in KSC's industrial area and placed in the cleanroom for intensive checkout. The ATM was scheduled to be moved in January 1973 to the Vehicle Assembly Building for mating with the OWS atop the two-stage Saturn V launch vehicle. The Skylab orbital assembly- consisting of the OWS, the ATM, and the AM/MDA-was scheduled to be launched from Pad A of Launch Complex 39 in late April 1973.

02 October 1972 A modules and experiments design certification review was convened at MSFC.

Representatives from NASA Hq, MSC, MSFC, KSC, Ames Research Center, LaRC, Department of Defense, Department of Transportation, various NASA contractors, and Principal Investigators attended. Purpose of the review was to assess and certify that the design of the OWS, MDA, payload shroud, AM, and ATM met Skylab requirements for performance, reliability, and safety.

11 October 1972 A cluster communications compatibility meeting was held at MSC. Representatives from MSFC, Goddard Space Flight Center, and MSC attended.

Purpose was to review the status of testing AM and ATM communications systems. AM audio and television systems were nearly complete. ATM telemetry and command systems were complete.

10 January 1973 Manned Space Flight Management Council meeting.

At a Manned Space Flight Management Council meeting, William C. Schneider (NASA Hq) emphasized the mounting pressures from open work at KSC and the demanding schedule for integrated systems testing during February and March. As examples he cited the following areas: February ATM system verification AM/MDA/OWS end-to-end system test SL-2 (first manned Skylab launch) vehicle roll March Stowage and crew compartment fit and function review SL-1 and SL-2 flight readiness test

22 January 1973 An ATM calibration rocket systems launch was accomplished at the White Sands Test Facility in New Mexico.

The launch was one of a series to qualify the calibration rocket program before the Skylab missions.

24 January 1973 An evaluation to determine the impact of changing the Skylab 1 and 2 launch dates indicated that the greatest impact was on the crew training activities. Program: Skylab.

The evaluation indicated that the star charts aboard the Orbital Workshop were launch-date dependent. Changeout packages were being prepared for the star charts which would be carried in the command module. Changeout packages were also being prepared for the rendezvous book, the ATM systems checklist and data book, the flight plan, and the flight plan sequence for the activation and deactivation checklist.

29 January 1973 Checkout of the AM/MDA and ATM flight units was completed at KSC, and the units were mated to the launch vehicle. Program: Skylab.

20 February 1973 The OWS high-fidelity mockup arrived at MSFC.

The OWS high-fidelity mockup arrived at MSFC from McDonnell Douglas, Huntington Beach. It was updated for use as a systems engineering mockup along with an AM/MDA and the ATM dynamic test articles, which were modified at MSFC for this use.

03 April 1973 An ATM Naval Research Laboratory rocket calibration launch was unsuccessful due to two major discrepancies.

l he guidance system failed to work properly and the recovery system failed. The launch was a qualification test flight of the rocket vehicle, science package, and support equipment which would he flown during the manned Skylab mission to calibrate the Naval Research Laboratory instrument in the ATM. This calibration would establish the amount of misalignment or degradation of the optics, if any, in the ATM instrument due to the launch environment or contamination. Investigations were initiated to determine the causes of the failures.

16 April 1973 The Skylab 1 spacecraft on its launch vehicle was moved to Launch Complex 39A. Program: Skylab.

The Skylab 1 spacecraft on its launch vehicle was moved to Launch Complex 39, Pad A, on 16 April. The SL-1 space vehicle consisted of two launch vehicle stages, an instrument unit, and the three major payload modules of the Saturn Workshop (SWS). The two launch vehicle stages and IU (S-IC, S-II, and S-IU) were identical to the first and second launch vehicle stages of the Apollo Saturn V space vehicle. The SL-1 payload consisted of the Orbital Workshop (a converted S-IVB stage), airlock module/multiple docking adapter, Apollo telescope mount, payload shroud, nose cone, and experiments. Additional Details: The Skylab 1 spacecraft on its launch vehicle was moved to Launch Complex 39A..

14 May 1973 Skylab 1 Program: Skylab. Launch Site: Cape Canaveral . Launch Vehicle: Saturn V. Mass: 74,783 kg. Perigee: 427 km. Apogee: 439 km. Inclination: 50.0 deg.

First and only US space station to date. Project began life as Apollo Orbital Workshop - outfitting of an S-IVB stage with docking adapter with equipment launched by several subsequent S-1B launches. Curtailment of the Apollo moon landings meant that surplus Saturn V's were available, so the pre-equipped, five times heavier, and much more capable Skylab resulted.

An unexpected telemetry indication of meteoroid shield deployment and solar array wing 2 beam fairing separation was received 1 minute and 3 seconds after liftoff. However, all other systems of the OWS appeared normal, and the OWS was inserted into a near-circular Earth orbit of approximately 435 km altitude. The payload shroud was jettisoned, and the ATM with its solar array was deployed as planned during the first orbit. Deployment of the Workshop solar array and the meteoroid shield was not successful. In fact the xternal solar/meteoroid shield had ripped off 63 seconds into ascent, tearing away one solar panel wing and debris jamming the remaining panel. Without shield temperatures soared in station. Repairs by crews led to virtually all mission objectives being met.

Following the final manned phase of the Skylab mission, ground controllers performed some engineering tests of certain Skylab systems--tests that ground personnel were reluctant to do while men were aboard. Results from these tests helped to determine causes of failures during the mission and to obtain data on long term degradation of space systems.

Upon completion of the engineering tests, Skylab was positioned into a stable attitude and systems were shut down. It was expected that Skylab would remain in orbit eight to ten years. It was to have been visited by an early shuttle mission, reboosted into a higher orbit, and used by space shuttle crews. But delays in the first flight of the shuttle made this impossible.

On July 11, 1979, Skylab disintegrated when it re-entered the earth's atmosphere after a worldwide scare over its pending crash. The debris stretched from the south-east Indian Ocean into Western Australia. Additional Details: Skylab 1.

26 May 1973 Second manned day of the Skylab mission. Program: Skylab.

The second manned day of the Skylab mission was focused on entry into the OWS and deployment of the Skylab parasol. Additional Details: Second manned day of the Skylab mission..

29 July 1973 Skylab 3 activation activities curtailed. Program: Skylab.

The Skylab 3 crewmen experienced motion sickness during the first three visit days. Consequently, the Orbital Workshop activation and experiment implementation activities were curtailed. By adjusting the crew's diet and maintaining a low workload, the crew was able to complete the adjustment to space flight in five days, after which flight activities returned to normal. On 25 September, the command module was reactivated and the crew performed the final OWS closeout. Following undocking and separation, the command module entered the atmosphere and landed in the Pacific Ocean approximately 300 km southwest of San Diego. Splashdown was at 6:20 p.m. EDT. The recovery ship, U.S.S. New Orleans, retrieved the command module and crew 42 minutes after landing. The total flight time was 1427 hours 9 minutes 4 seconds. Additional Details: Skylab 3 activation activities curtailed..

25 September 1973 All primary mission objectives for Skylab 3 were accomplished. Program: Skylab. Additional Details: All primary mission objectives for Skylab 3 were accomplished..
17 November 1973 Skylab Orbital Workshop activation by the crew of Skylab 4. Program: Skylab.

The reactivation included the reservicing of the airlock module primary coolant loop. The commander and pilot experienced symptoms resembling motion sickness during the initial three days of the visit, and flight plan activities were adjusted accordingly. Crew health was good thereafter. Additional Details: Skylab Orbital Workshop activation by the crew of Skylab 4..

24 January 1974 Significant repair and maintenance accomplishments of the three manned Skylab missions were reported. Program: Skylab.

Significant repair and maintenance accomplishments of the three manned Skylab missions were reported. Additional Details: Significant repair and maintenance accomplishments of the three manned Skylab missions were reported..

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