PART I (B)

Concept and Design

January 1962 through December 1962


January 3

"Gemini" became the official designation of the Mercury Mark II program. The name had been suggested by Alex P. Nagy of NASA Headquarters because the twin stars Castor and Pollux in constellation Gemini (the Twins) seemed to him to symbolize the program's two-man crew, its rendezvous mission, and its relation to Mercury. Coincidentally, the astronomical symbol (II) for Gemini, the third constellation of the zodiac, corresponded neatly to the Mark II designation.


First illustration of Gemini spacecraft
Figure 11. The first illustration of the Gemini spacecraft to be released publicly. It was distributed at the same time NASA announced that the project was to be named "Gemini." (NASA Photo S-62-88, released Jan. 3, 1962.)

January 3

Manned Spacecraft Center prepared a Statement of Work to be accomplished by Air Force Space Systems Division (SSD) in its role as contractor to NASA for the procurement of Titan II launch vehicles for the Gemini program. The launch vehicle would retain the general aerodynamic shape, basic systems, and propulsion concepts of the missile. Modifications, primarily for crew safety, were to be kept to a minimum. The Statement of Work accompanied a purchase request for $27 million, dated January 5, 1962, for 15 Titan launch vehicles. Pending ratification of the Gemini Operational and Management Plan, however, funding was limited to $3 million. To oversee this work, SSD established a Gemini Launch Vehicle Directorate, headed by Colonel Richard C. Dineen, on January 11. Initial budgeting and planning were completed by the end of March, and a final Statement of Work was issued May 14; although amended, it remained in effect throughout the program.

January 5

Manned Spacecraft Center published its first analysis of the Gemini spacecraft schedule. Potential problem areas in pulse-code-modulated (PCM) telemetry, the bipropellant attitude and control system, and time required to install electrical components and wiring had not yet affected the launch schedule. Scheduled launch dates were adjusted, however, because program approval had come a month later than originally anticipated in the Project Development Plan. The first flight was now planned for late July or early August 1963 with six-week launch centers between the first three flights. Subsequent launches would occur at two-month intervals, with the last flight in late April or early May 1965. The first Agena mission was scheduled for late February or early March 1964.

January 15

Director Robert R. Gilruth of Manned Spacecraft Center (MSC) appointed James A. Chamberlin, Chief of Engineering Division, as Manager of Gemini Project Office (GPO). The next day MSC advised McDonnell, by amendment No. 1 to letter contract NAS 9-170, that GPO had been established. It was responsible for planning and directing all technical activities and all contractor activities within the scope of the contract.

January 23

Manned Spacecraft Center completed an analysis of possible power sources for the Gemini spacecraft. Major competitors were fuel cells and solar cells. Although any system selected would require much design, development, and testing effort, the fuel cell designed by General Electric Company, West Lynn, Massachusetts, appeared to offer decided advantages in simplicity, weight, and compatiblity with Gemini requirements over solar cells or other fuel cells. A basic feature of the General Electric design, and the source of its advantages over its competitors, was the use of ion-exchange membranes rather than gas-diffusion electrodes. On March 20, 1962, McDonnell let a $9 million subcontract to General Electric to design and develop fuel cells for the Gemini spacecraft.


Diagram of Fuel Cell
Figure 12. The operating principle of the fuel cell designed by General Electric, adopted for use in the Gemini spacecraft. (McDonnell, "Project Gemini Familiarization Charts," June 5, 1962, unpaged.)

January 26

After investigating potential malfunction problems of the modified Titan II/Gemini launch vehicle, Martin-Baltimore prepared a study report with plans to provide the components necessary to ensure flight safety and enhance reliability. Martin defined the malfunction problem quantitatively in terms of the probability of each cause and its characteristic effect on the system and vehicle. Martin intended to keep the launch vehicle as much like the weapon system as possible; thus the data obtained from the Air Force's weapon system development program would be applicable to the launch vehicle. Only minimal modifications to enhance probability of mission success, to increase pilot safety, and to accommodate the Gemini spacecraft as the payload were to be made. These included a malfunction detection system; backup guidance, control, and hydraulic systems; and selective electrical redundancies.

January 31

Manned Spacecraft Center notified Marshall Space Flight Center, Huntsville, Alabama (which was responsible for managing NASA's Agena Programs) that Project Gemini required 11 Atlas-Agenas as rendezvous targets and requested Marshall to procure them. The procurement request was accompanied by an Exhibit "A" describing proposed Gemini rendezvous techniques and defining the purpose of Project Gemini as development and demonstrating Earth-orbit rendezvous techniques as early as possible. If feasible, these techniques could provide a practical base for lunar and other deep space missions. Exhibit B to the purchase request was a Statement of Work for Atlas-Agena vehicles to be used in Project Gemini. Air Force Space Systems Division, acting as a NASA contractor, would procure the 11 vehicles required. Among the modifications needed to change the Atlas-Agena into the Agena rendezvous vehicle were: incorporation of radar and visual navigation and tracking aids; main engines capable of multiple restarts; addition of a secondary propulsion system, stabilization system, and command system; incorporation of an external rendezvous docking unit; and provision of a jettisonable aerodynamic fairing to enclose the docking unit during launch. The first rendezvous vehicle was to be delivered to the launch site in 20 months, with the remaining 10 to follow at 60-day intervals.


Illustration of Rendezvous mission
Figure 13. Four stages in a rendezvous mission as conceived early in 1962. (NASA Photo S-62-82, c. Jan. 3, 1962.)

February 15

Air Force Space Systems Division issued a Technical Operating Plan to Aerospace Corporation, El Segundo, California, for support of the Gemini Launch Vehicle Program; a contract followed on March 15. Aerospace was to assume responsibility for general systems engineering and technical direction of the development of the launch vehicle and its associated subsystems. Aerospace had already established a Gemini Launch Vehicle Program Office in January.

February 19

Howard W. Tindall, Jr., Flight Operations Division, requested consolidation of all Gemini computer programming and operation at Manned Spacecraft Center in Houston. The complexity of trajectory control needed for rendezvous, the novelty of computer programming required (a management rather than an arithmetic problem), the lengthy time required for such a program, the need for programmers to work with flight controllers, were all reasons to locate this work solely in Houston with no part remaining at Goddard Space Flight Center, Greenbelt, Maryland. Goddard was the primary computing center for Mercury flights. Tindall also recommended a single-source contract with International Business Machines Corporation to equip the facility.

February 19

AiResearch Manufacturing Company, a division of the Garrett Corporation, Los Angeles, California, received a $15 million subcontract from McDonnell to manufacture the environmental control system (ECS) for the Gemini spacecraft. This was McDonnell's first purchase order on behalf of the Gemini contract. Patterned after the ECS used in Project Mercury (also built by AiResearch), the Gemini ECS consisted of suit, cabin, and coolant circuits, and an oxygen supply, all designed to be manually controlled whenever possible during all phases of flight. Primary functions of the ECS were controlling suit and cabin atmosphere, controlling suit and equipment temperatures, and providing drinking water for the crew and storage or disposal of waste water.

February 19

The initial coordination meeting between Gemini Project Office and McDonnell was held at Manned Spacecraft Center, Houston. Gemini Project Manager James A Chamberlin and McDonnell Engineering Manager Robert N Lindley outlined statements of policy. The purpose of subsequent coordination meetings was to discuss and settle problems arising between McDonnell and NASA. These coordination meetings were the central focus of decision-making during the development phase of the Gemini program. After five introduction meetings (February 19, 21, 23, 27 and 28), during which McDonnell representatives described spacecraft systems, regular business meetings began on March 5; subsequent meetings were tentatively scheduled for Monday, Wednesday, and Friday of each week.

February 20

McDonnell issued specifications for the crew-station system for the Gemini spacecraft. The crew-station system would include displays of spacecraft system functions, controls for spacecraft systems, and the means of integrating two crew members into the system. The specifications also established areas of responsibility for each crew member.


Figure 14. Block diagram of the Gemini environmental control system, subcontracted by McDonnell to AiResearch Manufacturing Co. (McDonnell, "Project Gemini Familiarization Charts," June 5, 1962, unpaged.)

February 22

Martin-Baltimore submitted its initial proposal for the redundant flight control and hydraulic subsystems for the Gemini launch vehicle; on March 1, Martin was authorized to proceed with study and design work. The major change in the flight control system from Titan II missile to Gemini launch vehicle was substitution of the General Electric Mod IIIG radio guidance system (RGS) and Titan I three-axis reference system for the Titan II inertial guidance system. Air Force Space Systems Division issued a letter contract to General Electric Company, Syracuse, New York, for the RGS on June 27. Technical liaison, computer programs, and ground-based computer operation and maintenance were contracted to Burroughs Corporation, Paoli, Pennsylvania, on July 3.

February 24

McDonnell let a $32 million subcontract to North American Aviation's Rocktdyne Division, Sacramento, California, to build liquid propulsion systems for the Gemini spacecraft. Two separate systems were required: the orbit attitude and maneuvering system (OAMS) and the reaction or reentry control system (RCS). The OAMS, located in the adapter section, had four functions: (1) providing the thrust required to enable the spacecraft to rendezvous with the target vehicle; (2) controlling the attitude of the spacecraft in orbit; (3) separating the spacecraft from the second stage of the launch vehicle and inserting it in orbit; and (4) providing abort capability at altitudes between 300,000 feet and orbital insertion. The OAMS initially comprised 16 ablative thrust chambers; eight 25-pound thrusters to control the spacecraft attitude in pitch, yaw, and roll axes; and eight 100-pound thrusters to maneuvre the spacecraft axially, vertically, and laterally. Rather than providing a redundant system, only critical components were to be duplicated. The RCS was located forward of the crew compartment in an independent RCS module. It consisted of two completely independent systems, each containing eight 25-pound thrusters very similar to those used in the OAMS. Purpose of the RCS was to maintain the attitude of the spacecraft during the reentry phase of the mission.


Drawing of OAMS and RCS in Gemini spacecraft
Figure 15. The general arrangement of liquid rocket systems (OAMS and RCS) in the Gemini spacecraft. The insert displays a typical thrust chamber assembly. (McDonnell, "Project Gemini Familiarization Charts," June 5, 1962, unpaged.)

February 28

Representatives of McDonnell, North American, Manned Spacecraft Center, and NASA Headquarters met to begin coordinating the interface between spacecraft and paraglider. The first problem was to provide adequate usable stowage volume for the paraglider landing system within the spacecraft. The external geometry of the spacecraft had already been firmly established, so the problem narrowed to determining possible volumetric improvements within the spacecraft's recovery compartment.

February 28

Manned Spacecraft Center (MSC) suballotted $5.2 million to Marshall Space Flight Center for procuring Atlas-Agena vehicles for Project Gemini. Marshall was to spend no more than $2 million, however, until a Statement of Work had been made definite. Regularly scheduled meetings were planned to resolve technical and management problems between MSC and Marshall. The first Atlas-Agena launch under this program was expected to take place on or about March 15, 1964.

March 5

Harold I. Johnson, Head of the Spacecraft Operations Branch of Manned Spacecraft Center's Flight Crew Operations Division, circulated a memorandum on proposed training devices for Project Gemini. A major part of crew training depended on several different kinds of trainers and simulators corresponding to various aspects of proposed Gemini missions. Overall training would be provided by the flight simulator, capable of simulating a complete mission profile including sight, sound, and vibration cues. Internally identical to the spacecraft, the flight simulator formed part of the mission simulator, a training complex for both flight crews and ground controllers that also included the mission control center and remote site displays. Training for launch and re-entry would be provided by the centrifuge at the Naval Air Development Center, Johnsville, Pennsylvania. A centrifuge gondola would be equipped with a mock-up of the Gemini spacecraft's interior. A static article spacecraft would serve as an egress trainer, providing flight crews with the opportunity to practice normal and emergency methods of leaving the spacecraft after landings on either land or water. To train flight crews in land landing, a boilerplate spacecraft equipped with a full-scale paraglider wing would be used in a flight program consisting of drops from a helicopter. A docking trainer, fitted with actual docking hardware and crew displays and capable of motion in six degrees of freedom, would train the flight crew in docking operations. Other trainers would simulate major spacecraft systems to provide training in specific flight tasks.


Gemini Flight Simulator
Figure 16. The two major types of simulators to be used in training crews for Gemini missions. The Gemini flight trainer (above) would simulate the entire mission, while the docking trainer (below) would simulate the final stages of rendezvous. (McDonnell, "Project Gemini Familiarization Charts," June 5, 1962, unpaged.)
Gemini Docking Simulator

March 5

Westinghouse Electric Corporation, Baltimore, Maryland, received a $6.8 million subcontract from McDonnell to provide the rendezvous radar and transponder system for the Gemini spacecraft. Purpose of the rendezvous radar, sited in the recovery section of the spacecraft, was to locate and track the target vehicle during rendezvous maneuvers. The transponder, a combined receiver and transmitter designed to transmit signals automatically when triggered by an interrogating signal, was located in the Agena target vehicle.


Rendezvous Radar System components
Figure 17. The location of the main elements of the rendezvous radar system on the Gemini spacecraft and the Agena target vehicle. (Charts presented by R. R. Carley (Gemini Project Office), "Project Gemini Familiarization Briefing," July 9-10, 1962.)

March 7

McDonnell awarded a $6.5 million subcontract to Minneapolis-Honeywell Regulator Company, Minneapolis, Minnesota, to provide the attitude control and maneuvering electronics system for the Gemini spacecraft. This system commanded the spacecraft's propulsion systems, providing the circuitry which linked the astronaut's operation of his controls to the actual firing of thrusters in the orbit attitude and maneuvering system or the reaction control system.


Diagram of OAMS electronics system
Figure 18. A functional block diagram of the attitude control and maneuvering electronics system of the Gemini spacecraft. (McDonnell, "Project Gemini Familiarization Charts," June 5, 1962, unpaged.)

March 7

Gemini Project Office accepted McDonnell's preliminary design of the spacecraft's main undercarriage for use in land landings and authorized McDonnell to proceed with detail design. Dynamic model testing of the undercarriage was scheduled to begin about April 1.

March 8

Manned Spacecraft Center directed North American to design and develop an emergency parachute recovery system for both the half-scale and full-scale flight test vehicles required by Phase II-A of the Paraglider Development Program and authorized North American to subcontract the emergency recovery system to Northrop Corporation's Radioplane Division, Van Nuys, California. North American awarded the $225,000 subcontract to Radioplane on March 16. This was one of two major subcontracts led by North American for Phase II-A. The other, for $227,000, went to Goodyear to study materials and test fabrics for inflatable structures.


Gemini Land-Landing Gear
Figure 19. Gemini landing gear: part of the land landing system along with the paraglider. (McDonnell, "Project Gemini Familiarization Charts," June 5, 1962, unpaged.)

March 12

Marshall Space Flight Center delivered an Agena procurement schedule (dated March 8) to Gemini Project Office. Air Force Space Systems Division (SSD) was to contract with Lockheed for 11 target vehicles. SSD assigned the Gemini Agena target vehicle program to its Ranger Launch Directorate, which was responsible for programs using Agena vehicles. Marshall also reported the expected delivery of a qualified multiple-restart main engine in 50 weeks, an improvement that removed this development requirement as the pacing item in Agena scheduling.

March 14

Gemini Project Office (GPO) decided that seat ejection was to be initiated manually, with the proviso that the design must allow for the addition of automatic initiation if this should later become a requirement. Both seats had to eject simultaneously if either seat ejection system was energized. The ejection seat was to provide the crew a means of escaping from the Gemini spacecraft in an emergency while the launch vehicle was still on the launch pad, during the initial phase of powered flight (to about 60,000 feet), or in case of paraglider failure after reentry. In addition to the seat, the escape system included a hatch actuation system to open the hatches before ejection, a rocket catapult to propel the seat from the spacecraft, a personnel parachute system to sustain the astronaut after his separation from the seat, and survival equipment for the astronaut's use after landing. At a meeting on March 29, representatives of McDonnell, GPO, Life Systems Division, and Flight Crew Operations Division agreed that a group of specialists should get together periodically to monitor the development of the ejection seat, its related components, and the attendant testing. Although ejection seats had been widely used in military aircraft for years, Gemini requirements, notably for off-the-pad abort capability, were beyond the capabilities of existing flight-qualified systems. McDonnell awarded a $1.8 million subcontract to Weber Aircraft at Burbank, California, a division of Walter Kidde and Company, Inc, for the Gemini ejection seats on April 9; a $741,000 subcontract went to Rocker Power, Inc., Mesa, Arizona, on May 15 for the escape system rocket catapult.


Ejection seat illustration
Figure 20. An artist's version of the use of ejection seats to escape from the Gemini spacecraft. The seats were to be used before launch (off-the-pad abort) or during the first phase of powered flight (to about 60,000 feet) if the launch vehicle malfunctioned. (McDonnell, "Project Gemini Familiarization Charts," June 5, 1962, unpaged.)

March 14

Manned Spacecraft Center issued its second analysis of the Gemini program schedule. Unlike the first, it considered launch vehicles as well as the spacecraft. Procurement of the Agena target vehicle had been initiated so recently that scope for analysis in that area was limited. A key feature of engineering development for the Gemini program was the use of a number of test articles, the lack of which had sometimes delayed the Mercury program; although constructing these test articles might cause some initial delay in Gemini spacecraft construction, the data they would provide would more than compensate for any delay. No problems beset launch vehicle development, but the schedule allowed little contingency time for unexpected problems. The first unmanned qualification flight was still scheduled for late July or early August 1963, but the second (manned) flight was now planned for late October or early November 1963 and the first Agena flight for late April or early Many 1964, with remaining flights to follow at two-month intervals, ending in mid-1965. Flight missions remained unchanged from the January analysis.

March 15

Gemini Project Office restated its intention to use Project Mercury hardware and subcontractors for Gemini. Justification for using different equipment or subcontractors was required for each item.

March 16

The Air Force successfully launched a Titan II intercontinental ballistic missile. This was the first full-scale test of the vehicle; it flew 5000 miles out over the Atlantic Ocean.

March 17

McDonnell awarded AiResearch a $5.5 million subcontract to provide the reactant supply system for the Gemini spacecraft fuel cells. The oxygen and hydrogen required by the fuel cell were stored in two double-walled, vacuum-insulated, spherical containers located in the adapter section of the spacecraft. Reactants were maintained as single-phase fluids (neither gas nor liquid) in their containers by supercritical pressures at cryogenic temperatures. Heat exchangers converted them to gaseous form and supplied them to the fuel cells at operating temperatures.


Diagram of fuel cell supply system
Figure 21. Block diagram of the reactant supply system for the Gemini spacecraft fuel cells. (MSC Flight Crew Operations Division, Crew Engineering, "Gemini Familiarization Package," Aug. 3, 1962.)

March 19

Advanced Technology Laboratories, Inc, Mountain View, California, received a $3.2 million subcontract from McDonnell to provide the horizon sensor system for the Gemini spacecraft. Two horizon sensors, one primary and one standby, were part of the spacecraft's guidance and control system. They scanned, detected, and tracked the infrared radiation gradient between Earth and space (Earth's infrared horizon) to provide reference signals for aligning the inertial platform and error signals to the attitude control and maneuver electronics for controlling the spacecraft's attitude and its pitch and roll axes.


Illustration of Horizon Sensor
Figure 22. Illustrating the operation of the horizon sensor for the Gemini spacecraft. (McDonnell, "Project Gemini Familiarization Charts," June 5, 1962, unpaged.)

March 19

Thiokol Chemical Corporation, Elkton, Maryland, received a $400,000 sub-contract from McDonnell to provide the retrograde rockets for the Gemini spacecraft. Only slight modification of a motor already in use was planned, and a modest qualification program was anticipated. Primary function of the solid-propellant retrorockets, four of which were located in the adapter section, was to decelerate the spacecraft at the start of the reentry maneuver. A secondary function was to accelerate the spacecraft to aid its separation from the launch vehicle in a high-altitude, suborbital abort.


Retrograde Rocket System
Figure 23. Location and arrangement of the retrograde rocket system in the Gemini spacecraft. (McDonnell, "Project Gemini Familiarization Charts," June 5, 1962, unpaged.)

March 21

Air Force Space Systems Division awarded a letter contract to Aerojet-General Corporation, Azusa, California, for the research, development, and procurement of 15 propulsion systems for the Gemini launch vehicle, as well as the design and development of the related aerospace ground equipment. Aerojet had been authorized to go ahead with work on the engines on February 14, 1962, and the final engine was scheduled for delivery by April 1965.

March 21

McDonnell awarded a $4.475 million subcontract to the Western Military Division of Motorola, Inc, Scottsdale, Airzona, to design and build the digital command system (DCS) for the Gemini spacecraft. Consisting of a receiver/decoder package and three relay packages, the DCS received digital commands transmitted from ground stations, decoded them and transferred them to the appropriate spacecraft systems. Commands were of two types: real-time commands to control various spacecraft functions and stored program commands to provide data updating the time reference system and the digital computer.


Figure 24. Gemini spacecraft communications system, which received ground commands for transfer to spacecraft systems. (McDonnell, "Project Gemini Familiarization Manual: Manned Spacecraft, Rendezvous Configuration," SEDR 300, June 1, 1962, p. 8-1.)

March 23

Air Force Space Systems Division published the "Development Plan for the Gemini Launch Vehicle System". From experience in Titan II and Mercury programs, the planners estimated a budget of $164.4 million, including a 50 percent contingency for cost increases and unforeseen changes.

March 28

McDonnell awarded a $2.5 million subcontract to Collins Radio Company, Cedar Rapids, Iowa, to provide the voice communications systems for the Gemini spacecraft. Consisting of the voice control center on the center instrument panel of the spacecraft, two ultrahigh-frequency voice transceivers, and one high-frequency voice transceiver, this system provided communications between astronauts, between the blockhouse and the spacecraft during launch, between the spacecraft and ground stations from launch through reentry, and between the spacecraft and recovery forces after landing.


Communication System use during Mission
Figure 25. Illustrating the stages of a mission during which various elements of the Gemini spacecraft communications system would be used. (Charts presented by J. Hoffman (GPO), "Project Gemini Familiarization Briefing," July 9-10, 1962.)

March 29

The St. Petersburg, Florida, Aeronautical Division of Minneapolis-Honeywell received an $18 million subcontract from McDonnell to provide the inertial measuring unit (IMU) for the Gemini spacecraft. The IMU was a stabilized inertial platform including an electronic unit and a power supply. Its primary functions were to provide a stable reference for determining spacecraft attitude and to indicate changes in spacecraft velocity.


Inertial Guidance System
Figure 26. The Gemini spacecraft inertial guidance system. (McDonnell, "Project Gemini Familiarization Manual: Manned Spacecraft Rendezvous Configuration," SEDR 300, June 1, 1962, p. 7-23.)

March 30

Martin-Baltimore submitted a "Description of the Launch Vehicle for the Gemini Spacecraft" to Air Force Space Systems Division. This document laid the foundation for the design of the Gemini launch vehicle by defining the concept and philosophy of each proposed subsystem.

March 31

The configuration of the Gemini spacecraft was formally frozen. Following receipt of the program go-ahead on December 22, 1961, McDonnell began defining the Gemini spacecraft. At that time, the basic configuration was already firm. During the three-month period, McDonnell wrote a series of detailed specifications to define the overall vehicle, its performance, and each of the major subsystems. These were submitted to NASA and approved. During the same period, the major subsystems specification control drawings - the specifications against which equipment was procured - were written, negotiated with NASA, and distributed to potential subcontractors for bid.

April 3

Representatives of Manned Spacecraft Center, Ames Research Center, Martin, and McDonnell met to discuss the participation of Ames in the Gemini wind tunnel program. The tests were designed to determine: (1) spacecraft and launch vehicle loads and the effect of the hatches on launch stability, using a six percent model of the spacecraft and launch vehicle; (2) the effect of large angles of attach, Reynold's number, and retrorocket jet effects on booster tumbling characteristics and attachment loads; (3) exit characteristics of the spacecraft; and (4) reentry characteristics of the reentry module.


Spacecraft Components
Figure 27. Gemini spacecraft nomenclature. (McDonnell, "Project Gemini Familiarization Manual: Manned Spacecraft Rendezvous Configuration," SEDR 300, June 1, 1962, p. 2-3.)

April 4

Manned Spacecraft Center awarded the Aerospace and Defense Products Division of B.F. Goodrich Company, Akron, Ohio, a cost-plus-fixed-fee contract for $209,701 to design, develop, and fabricate prototype pressure suits. Related contracts went to Arrowhead Products Division of Federal-Mogul Corporation, Los Alamitos, California, and Protection, Inc., Gardena, California. B.F. Goodrich had begun work related to the contract on January 10, 1962. The contract covered two separate pressure suit development programs, neither of them initially identified with a particular manned space flight program. The original Statement of Work required B. F. Goodrich to produce four successively improved prototypes of an advanced full-pressure suit, and two prototypes of a partial-wear, quick-assembly, full-pressure suit. The contract was amended on September 19, 1962, to identify the development programs specifically with Project Gemini.

April 7

ACF Electronics Division, Riverdale, California, of ACF Industries, Inc., received a $1 million subcontract from McDonnell to provide C- and S-band radar beacons for the Gemini spacecraft. These beacons formed part of the spacecraft's tracking system. With the exception of frequency-dependent differences, the C-band beacon was nearly identical to the S-band beacon. Their function was to provide tracking responses to interrogation signals from ground stations.


Tracking Aids
Figure 28. Gemini spacecraft tracking aids (beacon system). (McDonnell, "Project Gemini Familiarization Charts," June 5, 1962, unpaged.)

April 9

Earl Whitlock of McDonnell presented a "Gemini Manufacturing Plan" (dated April 6) to Gemini Project Office (GPO). The schedule called for production spacecraft No. 1 to be followed by static article No. 1. Because of the normally poor quality of a first production item, GPO asked McDonnell to start static article No. 1 first on or about May 15, 1962, while leaving spacecraft No. 1 where it was in the schedule. McDonnell's contract called for four static articles, ground test units similar in construction to, and using the same material as, flight articles.

April 12

Manned Spacecraft Center confirmed that a five-day orbital lifetime of Agena systems would be adequate for currently planned missions.

April 13

Martin-Baltimore and Air Force Space Systems Division (SSD) reported to Gemini Project Office on the problems of establishing abort criteria for the malfunction detection system (MDS). Manned Spacecraft Center had formed a task force of Martin, McDonnell, and Aerospace personnel to begin a maximum effort to define overall abort criteria. On April 23, Martin submitted to SSD its descriptive study and proposed configuration of the MDS, intended to monitor the performance of launch vehicle subsystems and display the data to the astronauts. The abort decision was to be the astronauts' alone. A launch abort simulation study by Chance Vought Corporation, Dallas, Texas, completed in April showed the feasibility and desirability of manually initiated abort.

April 18

NASA announced that applications would be accepted for additional astronauts until June 1, 1962. NASA planned to select five to ten astronauts to augment the seven-member Mercury astronaut team. The new pilots would participate in support operations in Project Mercury and would join the Mercury astronauts in piloting the two-man Gemini spacecraft. To be chosen, the applicant must (1) be an experienced jet test pilot and preferably be presently engaged in flying high-performance aircraft; (2) have attained experimental flight test status through military service, aircraft industry, or NASA, or must have graduated from a military test pilot school; (3) have earned a degree in the physical or biological sciences or in engineering; (4) be a United States citizen under 35 years of age at the time of selection, six feet or less in height; and (5) be recommended by his parent organization. Pilots meeting these qualifications would be interviewed in July and given written examinations on their engineering and scientific knowledge. Selected applicants would then be thoroughly examined by a group of medical specialists. The training program for the new astronauts would include work with design and development engineers, simulator flying, centrifuge training, additional scientific training, and flights in high-performance aircraft.

April 19

McDonnell awarded a $26.6 million subcontract to International Business Machines (IBM) Corporation's Space Guidance Center, Owego, New York, to provide the computer system for the Gemini spacecraft. The digital computer was the heart of the spacecraft's guidance and control system; supplementary equipment consisted of the incremental velocity indicator (which visually displayed changes in spacecraft velocity), the manual data insertion unit (for inserting data into, and displaying readouts from, the computer), and the auxiliary computer power unit (to maintain stable computer input voltages). In addition to providing the computer and its associated equipment, IBM was also responsible for integrating the computer with the systems and components it connected with electrically, including the inertial platform, rendezvous radar, time reference system, digital command system, data acquisition system, attitude control and maneuver electronics, the launch vehicle autopilot, console controls and displays, and aerospace ground equipment.


Guidance and Control System
Figure 29. Block diagram of the Gemini spacecraft guidance and control system. (McDonnell, "Project Gemini Familiarization Charts," June 5, 1962, unpaged.)

April 25

Studebaker Corporation's CTL Division, Cincinnati, Ohio, received a subcontract for $457,875 from McDonnell to provide two backup heatshields for the Gemini spacecraft, similar in material and fabrication technique to those used in Project Mercury. The CTL heatshield would be used only if a new shield McDonnell was working on proved unusable. Test results from screening advanced heatshield materials had yielded four promising materials. McDonnell had contracted with Vidya, Inc., Palo Alto, California (March 16), and Chicago Midway Laboratories, Chicago, Illinois (mid-April), to test the new ablation materials.

April 26

At an Atlas-Agena coordination meeting, Lockheed presented a comprehensive description of its proposed propulsion development plans for the Gemini-Agena. Lockheed's planned program included: propulsion system optimization studies, a multiple-restart development program for the primary propulsion system, and a development program for the secondary propulsion system.

April 26-27

Representatives of North American, NASA Headquarters, Langley Research Center, Flight Research Center, Ames Research Center, and Manned Spacecraft Center met to review the design and testing philosophy for the half-scale test vehicle (HSTV) in phase II-A of the Paraglider Development Program. After the emergency parachute recovery system had been qualified, the HSTV would be used to evaluate paraglider stability and control in drop tests with the wing predeployed and to provide empirical data on the functioning of vehicle systems in deployment tests. At the end of the review, the NASA Half Scale Test Vehicle Design Review Board recommended 21 changes in test vehicle design and test procedures to North American.

May 1

McDonnell proposed to evaluate the Gemini redezvous radar and spacecraft maneuvering system on early flights by using a rendezvous evaluation pod to be ejected from the spacecraft in orbit. Manned Spacecraft Center (MSC) liked the idea and asked McDonnell to pursue the study. During the last week in June, McDonnell received approval from MSC to go ahead with the design and development of the rendezvous pod. It would contain a radar transponder, C-band beacon, flashing light, and batteries.

May 1

Air Force Space Systems Division (SSD) awarded a letter contract to Lockheed Missiles and Space Company for eight Agena vehicles to be modified as Gemini Agena target vehicles (GATV). Mission requirements were to (1) establish a circular orbit within specified limits, (2) provide a stable target with which the spacecraft could rendezvous and dock, (3) respond to commands from either ground stations or the spacecraft, (4) perform a complex series of orbital maneuvers by means of either real-time or stored commands if less than optimum launch of Agena or spacecraft occurred, and (5) provide an active orbit life of five days. Lockheed's analysis of these mission requirements provided the design criteria for the major modifications required to adapt the Agena to the Gemini mission: (1) modification of the primary propulsion system; (2) addition of a secondary propulsion system (two 16-pound and two 200-pound thrusters) to provide ullage orientation and minor orbit adjustments; (3) design of a digital command and communications subsystem including a programmer, controller, pulse-code-modulated telemetry system, and onboard tape recorder; (4) design of changes to provide the guidance and control functions peculiar to the GATV; and (5) addition of an auxiliary forward equipment rack with an interface capable of supporting the target docking adapter. On direction from Air Force Systems Command Headquarters, SSD authorized Lockheed to proceed with the Gemini-Agena program on March 19.

May 1

Following a Lockheed briefing on pulse-code-modulation (PCM) instrumentation systems, representatives of Goddard Space Flight Center and Manned Spacecraft Center (MSC) formed a small working group to discuss the feasibility of making the Gemini telemetry system a full PCM system. PCM was a digital telemetry system which could provide more channels of information, faster data rates, improved accuracy, and less weight of equipment per data channel. Goddard had already reviewed several PCM ground station proposals and had concluded that such a system could handle future NASA programs. All who attended the meeting agreed that a full PCM telemetry system, airborne and ground, could be implemented in time to support the Gemini program. Gemini Project Office approved the formation of an MSC-Gemini PCM Instrumentation Working Group to be responsible for the implementation and compatibility of the airborne and ground PCM system for Gemini. On June 27, Walter C. Williams, MSC Associated Director, notified Goddard of NASA's decision "to utilize a PCM telemetry system for Gemini and Agena real time data." Ten sites were selected for the installation of PCM equipment; each of these also received dual acquisition equipment, dual digital command system, and pulse coders for distinguishing between the manned Gemini spacecraft and the Agena target when both were in orbit.

May 4

Manned Spacecraft Center issued its third analysis of the Gemini program schedule. Spacecraft ground test plans had been formulated, and the construction of test hardware had begun. Two boilerplate spacecraft had been added to the program to facilitate ground testing. Flight No. 2 was the first planned to use paraglider, but the paraglider program required close attention to prevent schedule slippage; plans to substitute a parachute landing system for paraglider in this flight, should it prove necessary, had been initiated. Spacecraft manufacturing schedules were endangered by late delivery of components from vendors: chief threats to spacecraft No. 1 were components of the instrument and recording system and the inertial platform; for spacecraft No. 2, communication and electrical system components. No problems were anticipated with the booster. The analysis indicated no change in the launch schedule.

May 10-11

Gemini Project Office directed McDonnell to determine what would be involved in opening and closing the spacecraft hatches in the space environment and Manned Spacecraft Center's Life Systems Division to determine what special pressure suit features would be required to provide crew members with a 15-minute extravehicular capability.

May 10-11

Manned Spacecraft Center's Life Systems Division proposed to measure seven parameters for determining crew condition during all Gemini flights. These were, in order of priority: blood pressure, with electrocardiogram and phoncardiogram serving as first and second backup; electroenecephalogram; respiration, galvanic skin response, and body temperature. The bioinstrumentation required would cost about three and one-half pounds per man, with a total power consumption of about two watt-hours and the shared use of six channels of telemetry. Gemini Project Office reviewed these requirements and approved the following measurements: electrocardiogram, respiration rate and depth, oral temperature, blood pressure, phonocardiogram, and nuclear radiation does. Biomedical measurement devices had still to be designed, developed, qualified, and procured.

May 10-11

The postlanding survival kit proposed for use by Gemini crew members would be basically similar to the one used in Project Mercury. Each kit would weigh about 24 pounds, and one kit would be provided for each crew member.

May 11

Manned Spacecraft Center (MSC) decided to establish a liaison office at Martin-Baltimore. Scott H Simpkinson of Gemini Project Office assumed the post on May 15, but he was soon replaced by Harle Vogel, who remained in the position throughout the program. The purpose of the office was to facilitate exchange of information between MSC and Martin.

May 12

James E. Webb, NASA's new Administrator, reviewed the Gemini program. Project Gemini cost estimates at this point (£744.3 million) had increased substantially over the original estimate of $250 million. Estimated spacecraft cost had risen from $240.5 to $391.6 million; Titan II cost, from $113.0 to $161.8 million; Atlas-Agena, from $88.0 to $106.3 million; and supporting development (including the paraglider program), from $29.0 to $36.8 million. Estimated operations costs had declined from $59.0 to $47.8 million.

May 14-15

Representatives of McDonnell, Northrop Ventura (formerly Radioplane), Weber Aircraft, and Manned Spacecraft Center attended the first ejection seat design review at McDonnell in St Louis.

May 16-17

A Launch Vehicle-Spacecraft Interface Working Group was established. Gemini Project Office (GPO) and Aerospace had agreed on the need for such a group at a Gemini-Titan coordination meeting on May 11. The main function of the group, composed of Martin and McDonnell personnel with a McDonnell representative as chairman, was to provide mutual exchange of design and physical data on mechanical, electrical, and structural details between the spacecraft contractor and the booster contractor. The group would make no policy decisions; its actions were to be reviewed at regularly scheduled coordination meetings held by GPO.

May 16-17

At a mechanical systems coordination meeting, representatives of McDonnell and Gemini Project Office decided to develop more powerful retrograde rocket motors for the Gemini spacecraft. The new motors, similar in configuration to the old but with some three times the thrust level, would permit retrorocket aborts at altitudes as low as 72,000 to 75,000 feet. McDonnell's original subcontract with Thiokol was accordingly terminated and a new subcontract was let on July 20. Development of the new motors was expected to cost $1.255 million.


Figure 30. The solid-propellant retrograde rocket motor for the Gemini spacecraft. (McDonnell, "Project Gemini Familiarization Manual: Manned Spacecraft Rendezvous Configuration," SEDR 300, June 1, 1962, p. 11-30.)

May 18

McDonnell subcontracted the parachute landing system for Gemini to Northrop Ventura at an estimated cost of $1,829,272. The parachute landing system was to be used for the first Gemini flight. Gemini Project Office had decided in April on using a single-chute system, one 84.2-foot diameter ring-sail parachute. At a mechanical systems coordination meeting in Houston on May 16-17, however, it was decided to add an 18-foot ring-sail drogue parachute to the system. McDonnell proposed deploying the drogue at 10,000 feet, two seconds after release of the rendezvous and recovery system. Fifteen seconds later the main recovery parachute would switch from single-point to two-point suspension, followed in five seconds by the initiation of reaction control system propellant dump which would take no longer that 105 seconds. The recovery parachute would be jettisoned shortly after impact. At another coordination meeting on May 23-24, Manned Spacecraft Center concurred in this proposed sequencing.


Parachute Recovery System
Figure 31. The parachute recovery system to be used instead of paraglider on the first Gemini spacecraft: stowed and deployed modes. (McDonnell, "Project Gemini Engineering Mockup Review," Aug. 15-16, 1962, p. 39.)

May 21

McDonnell awarded an $8 million subcontract to Electro-Mechanical Research, Inc., Sarasota, Florida, to provide the data transmission system for the Gemini spacecraft. Both the spacecraft and target vehicle used pulse-code-modulation (PCM) telemetry, a technique for encoding data in digital form by varying the length of pulses to from an information-carrying code. Once encoded, measurements were transmitted over a radio link to ground receiving stations. The data transmission system consisted of a PCM subsystem, an onboard tape recorder, and two VHF transmitters; it was capable of transmitting data in real time or delayed time.

May 21

Amendment No. 6 to the Gemini launch vehicle procurement contract assigned $2.609 million to fund the construction necessary to convert pad 19 at Cape Canaveral for Gemini flights. The Air Force had originally constructed pad 19 for the Titan I development program. Following the final Titan I development flight (January 29) from the Cape, design of the required modifications had begun in February. In April, Gemini Project Office decided that Pad 19 would have an erector rather than a gantry, the upper third of which would be designed as a white room. The final design review of pad 19 modifications took place July 9-10, and the Army Corps of Engineers awarded the construction contract to Consolidated Steel, Cocoa Beach, Florida. Construction began in September. Work was completed and pad 19 was activated on October 17, 1963.

May 23

Representatives of McDonnell and Manned Spacecraft Center completed a series of 24 meetings to negotiate the technical details of McDonnell's plans for supporting and documenting Project Gemini, specifications for Gemini systems and subsystems, environmental and structural design criteria for the spacecraft, spacecraft performance specifications, test programs, and plans for reliability, quality assurance, and validation. Meetings had begun April 19.

May 23

Ames Research Center began the first wind tunnel test of the half-scale inflatable paraglider wing in support of the Paraglider Development Program. This was the first test of a large-scale inflatable paraglider wing in the full-scale test facility. Purpose of the test was to obtain basic aerodynamic and loads data for the combined wing/spacecraft system and to spot and evaluate potential aerodynamic and design problem areas. The flight regimes studied included wing deployment as well as glide, preflare, and flare. In the last stages of the test, the sail ripped. Since the basic objectives had already been achieved, and the failure occurred under conditions more stringent than any expected during flight testing, only minor corrective action was considered necessary and the test was not repeated. Testing ended July 25; at a paraglider landing system coordination meeting on July 26, the Ames test program was considered completed.

May 23-24

Manned Spacecraft Center concurred in McDonnell's proposed sequencing of the paraglider recovery system. In a normal mission, the drogue parachute (a small parachute to pull the recovery compartment away from the spacecraft and strip the paraglider from the recovery compartment) would deploy at 60,000 feet, followed by the release of the rendezvous and recovery section at 50,000 feet. Starting at 10,000 feet, all reaction control system propellant remaining after the paraglider had been deployed would be dumped. The paraglider wing itself would be jettisoned shortly after touchdown. At this point, plans called for the paraglider to be used on all Gemini missions except the first.


Paraglider Deployment
Figure 32. The proposed sequence of events in deploying the paraglider to land the Gemini spacecraft. (McDonnell, "Project Gemini Familiarization Manual: Manned Spacecraft Rendezvous Configuration," SEDR 300, June 1, 1962, p. 12-8.)

May 24

North American began a test program to qualify the emergency parachute system for the half-scale flight test vehicle required for Phase II-A of the Paraglider Development Program. The first two drop tests were successful (May 24, June 20); but during the third (July 10), the main recovery parachute failed to deploy. The trouble was analyzed and detailed modifications were worked out at a meeting on August 16 between North American and Northrop Ventura. The modifications proved successful in the fourth test (September 4), and Manned Spacecraft Center concurred with North American in judging the emergency parachute system for the half-scale test program to be qualified.


Emergency Parachute System for Paraglider Tests
Figure 33. The emergency parachute recovery system for the half-scale paraglider flight test vehicle for Phase II-A of the development program. (North American Aviation, Inc., Space and Information Systems Division, Paraglider Projects, "Midterm Progress Report, Paraglider Development Program, Phase II, Part A, System Research and Development," SID 62-391, Apr. 20, 1962, p. 228.)

May 29

Representatives of McDonnell, Weber Aircraft, Gemini Procurement Office, Life Systems Division, Gemini Project Office, and US Naval Ordnance Test Station, China Lake, California, concluded plans for development testing of the spacecraft ejection seat. Requirements peculiar to the Gemini spacecraft, in particular off-the-pad abort capability, caused the plan to stress testing from a stationary tower early in the test program. The purpose of these simulated off-the-pad ejection tests was to investigate the effects of varying the center of gravity on the trajectory of the ejected seat and to optimize the timing of the recovery sequence. Tower tests began July 2. They were to be followed by rocket sled ejection tests to investigate simultaneous ejection with open hatches at maximum dynamic pressure. Sled tests actually began on November 9, before tower tests had been completed.


Off-the-Pad escape mode
Figure 34. The "off-the-pad" escape mode for an aborted Gemini mission. (Charts presented by K. Hecht, "Project Gemini Familiarization Briefing," July 9-10, 1962, unpaged.)

June 1

A list of the aerospace ground equipment required to handle and check out the Gemini spacecraft before flight was presented at the first spacecraft operations coordination meeting.

June 4

The Air Force School of Aviation Medicine, Brooks Air Force Base, Texas, began a simulated long-duration Gemini mission. Two men were to live for 14 days in a 100-percent-oxygen atmosphere maintained at a pressure of 5 pounds per square inch, the proposed spacecraft environment.

June 6

McDonnell was authorized to procure an additional boilerplate spacecraft for parachute landing system tests. The original plan called for McDonnell to use the boilerplate spacecraft fabricated by North American for qualification testing of the emergency parachute system for the paraglider drop tests. McDonnell estimated, however, that modifying the North American boilerplate would cost from $17,000, to $19,000, whereas a new boilerplate would cost from $10,000 to $12.000.

June 6

Whirlpool Corporation Research Laboratories, St Joseph, Michigan, received a contract from Manned Spacecraft Center (MSC) to provide the Project Gemini food and waste management system, comprising water dispenser, food storage, and waste storage components. Food and zero-gravity feeding devices were to be provided by the US Army Quartermaster Corps Food and Container Institute, Chicago, Illinois. MSC's Life Systems Division was responsible for directing the development program.

June 20

Manned Spacecraft Center authorized North American to go ahead with Phase II, Part B(1), of the Paraglider Development Program. Letter contract NAS 9-539 followed. Under this contract, North American was to design, build and test an advanced two-man paraglider trainer, to initiate a flight simulation program for pilot training, and to complete the design of a man-rated Gemini paraglider wing. The final contract was awarded on October 31, 1962.

June 21-22

A paraglider full-scale test vehicle Design Engineering Inspection was held at North American's Space and Information Systems Division in Downey, California. The Manned Spacecraft Center inspecting team reviewed the design of the full-scale paraglider wing, capsule, and associated equipment, as well as the test program and schedules for Phase II-A of the Paraglider Development Program. The team suggested 33 changes, mostly related to hardware.

June 25

Gemini Project Office reported that a thorough study of the reentry tracking histories of the Mercury-Atlas 4, 5, 6 and 7 missions had been completed. The study indicated that a C-band radar tracking beacon should be integrated into the spacecraft reentry section in place of the planned S-band beacon. The change would improve the probability of tracking spacecraft reentry through the ionization zone.

June 27-28

After considering Gemini related investigations that might be carried out with the help of Mercury, Gemini Project Office and McDonnell decided that the most useful would be testing heatshield materials and afterbody-shingle characteristics. Samples of the Gemini heatshield were later flown satisfactorily on the Mercury-Atlas 8 Sigma 7 mission.

June 28

McDonnell and North American representatives met for the first time to exchange detailed technical information on the installation of the paraglider in the spacecraft.

June 30

Martin-Baltimore's airborne systems functional test stand went into operation at Baltimore. In this 3000-square-foot facility, all airborne systems in the Gemini launch vehicle - including flight control, hydraulic, electrical, instrumentation, and malfunction detection - were assembled on tables and benches; actual engines, but simulated propellant tanks and guidance, were used. In addition to individual and combined systems tests, the facility was used to check system design changes and trouble-shoot problems encountered in other test programs.


Test stand at Martin-Baltimore
Figure 35. Airborne systems functional test stand at Martin's Baltimore plant. (Martin, Gemini-Titan II Air Force Launch Vehicle, Press Handbook, Feb. 2, 1967, p. 4-3.)

July 2

Simulated off-the-pad ejection tests began at Naval Ordnance Test Station. Five ejections were completed by the first week of August. The tests revealed difficulties which led to two important design changes: the incorporation of a drogue-gun method of deploying the personnel parachute and the installation of a three-point restraint-harness-release system similar to those used in military aircraft. August 6-7 representatives of Manned Spacecraft Center and ejection system contractors met to review the status of ejection seat design and the development test program. They decided that off-the-pad ejection tests would not be resumed until ejection seat hardware reflected all major anticipated design features and the personnel parachute had been fully tested. Design changes were checked out in a series of bench and ground firings, concluding on August 30 with a successful inflight drop test of a seat and dummy. Off-the-pad testing resumed in September.

July 3

Gemini Project Office met with representatives of Manned Spacecraft Center's Flight Operations Divisions, McDonnell, International Business Machines, Aerospace, Air Force Space Systems Division, Lockheed, Martin, Space Technology Laboratories, Inc. (Redondo Beach, California), and Marshall Space Flight Center to outline the work to be done before final mission planning. A center coordinating group, with two representatives from each agency, was established.

July 6

Martin prepared a plan for flight testing the malfunction detection system (MDS) for the Gemini launch vehicle on development flights of the Titan II weapon system. Gemini Project Office (GPO) had requested Martin to prepare Systems Division and Aerospace approved the plan and won GPO concurrence early in August. This so-call "piggyback plan" required installing the Gemini MDS in Titan II engines on six Titan II flights to demonstrate its reliability before it was flown on Gemini.

July 11

The capability for successfully accomplishing water landings with either the parachute landing system or the paraglider landing system was established as a firm requirement for the Gemini spacecraft. The spacecraft would be required to provide for the safety of the crew and to be seaworthy during a water landing and a 36-hour postlanding period.

July 12

Representatives of Gemini Project Office (GPO), Flight Operations Division, Air Force Space System Division, Marshall Space Flight Center, and Lockheed attended an Atlas-Agena coordination meeting in Houston. GPO presented a list of minimum basic maneuvers of the Agena to be commanded from both the Gemini spacecraft and ground command stations. GPO also distributed a statement of preliminary Atlas-Agena basic mission objectives and requirements. A total of 10 months would be required to complete construction and electrical equipment checkout to modify pad 14 for the Atlas-Agena, beginning immediately after the last Mercury flight.

July 12

At technical team at Air Force Missile Test Center, Cape Canaveral, Florida - responsible for detailed launch planning, consistency of arrangements with objectives, and coordination - met for the first time with official status and a new name. The group of representatives from all organizations supplying major support to the Gemini-Titan launch operations, formerly called the Gemini Operations Support Committee, was now called the Gemini-Titan Launch Operations Committee.

July 13

To ensure mechanical and electrical compatibility between the Gemini spacecraft and the Gemini-Agena target vehicle, Gemini Project Office established an interface working group composed of representatives from Lockheed, McDonnell, Air Force Space Systems Division, Marshall, and Manned Spacecraft Center. The group's main function was to smooth the flow of data on design and physical details between the spacecraft and target vehicle contractors.

July 19

Gemini Project Office and North American agreed on guidelines for the design of the advanced paraglider trainer, the paraglider system to be used with static test article No. 2, and the paraglider system for the Gemini spacecraft. The most important of these guidelines was that redundancy would be provided for all critical operations.

July 20

NASA Administrator James E Webb announced officially that a new mission control center for manned space flight would be established at Manned Spacecraft Center (MSC) in Houston. Project Mercury flights were controlled from the center at Cape Canaveral, but these facilities were inadequate for the more complex missions envisioned for the Gemini and Apollo programs. Philco Corporation's Western Development Laboratories, Palo Alto, California, had received a contract in April 1962 to study a design concept for the flight information and control functions of the mission control center. The US Army Corps of Engineers would supervise construction of this center as it had all major facilities at MSC. The control center was expected to be operational in 1964 for Gemini rendezvous flights and to cost about $30 million.

July 25

McDonnell reported reducing the rated thrust of the two forward-firing thrusters from 100 pounds to 85 pounds to reduce disturbance torques generated in the event of maneuvers with one engine out.

July 25-26

A reliability review of the Titan II launch vehicle engine system was held in Sacramento, California, at Aerojet-General's Liquid Rocket Plant, the site where the engines were being developed. Gemini engines had to be more reliable than did intercontinental ballistic missile (ICBM) engines. This requirement meant supplementing the ICBM engine reliability program, a task being performed by Aerojet under Air Force Space Systems Division direction.

August 2

Lockheed presented study findings and design recommendations on the Agena D propulsion systems to representatives of Marshall, Manned Spacecraft Center, and Air Force Space Systems Division in a meeting at Houston. During July, NASA and the Air Force had tentatively decided to substitute the Agena D for the Agena B in the Gemini program. Lockheed's presentation at Houston was the final report on the analysis phase of the Gemini-Agena effort. It included Lockheed's evaluation of the designs of both the primary and secondary propulsion systems and its analysis of tests on the start system of the multiple-restart main engine recently completed by Bell Aerosystems Company, Buffalo, New York, the engine subcontractor. A pressurize-start tank system was selected in September.

August 2

North American began a test program to qualify the emergency parachute recovery system for the full-scale test vehicle in Phase II-A of the Paraglider Development Program. The first test was successful. In the second test (August 22), one of the three main parachutes was lost after deployment, but no damage resulted. In the third test (September 7), only minor damage was sustained despite the loss of two parachutes. The test series ended on November 15 when all recovery parachutes separated from the spacecraft immediately after deployment and the test vehicle was destroyed on impact. Manned Spacecraft Center decided to terminate this portion of the test program but directed McDonnell to supply North American with a boilerplate spacecraft for further tests at a later date.


Emergency Parachute System for Paraglider Tests
Figure 36. The emergency parachute recovery system for the full-scale paraglider flight test vehicle. (North American Aviation, Inc., Space and Information Systems Division, Paraglider Projects, "Midterm Progress Report, Paraglider Development Program, Phase II, Part A, System Research and Development," SID 62-391, Apr. 20, 1962.)

August 3

At a meeting in Los Angeles, the Air Force described to Gemini Project Office its plans for converting complex 14 at Atlantic Missile Range, Cape Canaveral, Florida. Complex 14, the site of mercury launches, would be modified for Project Gemini operations as the target vehicle launch site. The Air Force accepted the responsibility for funding, designing, modifying, and equipping the complex to an Atlas-Agena configuration. This action was scheduled as follows: preliminary design criteria by September 1 and final design criteria by October 1, 1962. Mercury Project Office reported that complex 14 would be available for Gemini on September 1, 1963.

August 9

Flight Control Operations Branch of Manned Spacecraft Center's Flight Operations Division outlined a program of training for Gemini flight controllers. This program included: (1) contractor in-plant training, a one-month course of instruction a McDonnell through which would cycle three classes of 10-15 persons and which would include three weeks of detailed systems training, one week of hardware training, and McDonnell drawing-standard familiarization; (2) individual training of flight controllers in systems and network operations, systems updating, and practical exercises; (3) team training, to include site training, for supporting personnel teams, command site teams, and remote site teams; and (4) network training in the control, communications, and decision-making aspects of the network flight control organization, and in detailed checkout of operational procedures, countdowns, systems tests, and network equipment. Because of experience in the earlier program, Mercury flight controllers would be assigned as flight controllers for Project Gemini, although their numbers would be augmented to meet the increased demands of the advanced program.

August 14

North American began flight tests of the half-scale vehicle (HSTV) in Phase II-A of the Paraglider Development Program two months behind schedule. The instrumented HSTV with the paraglider predeployed was towed aloft by helicopter. Objectives of the predeployed flights were to evaluate flight performance, longitudinal and lateral control characteristics, effectiveness of control, and the flare maneuver capability of the paraglider. Despite various minor malfunctions in all five test flights (August 14, 17, 23, September 17, and October 23, 1962), test results verified the stability of the wing/vehicle combination in free flight and the adequacy of control effectiveness.

August 15-16

Manned Spacecraft Center (MSC) formally reviewed McDonnell's engineering mock-up of the Gemini spacecraft in St Louis. The company had begun building the mock-up in January, shortly after receiving the spacecraft contract. Mock-up review had originally been scheduled for mid-July, but informal examinations by MSC representatives, including James A Chamberlin and several astronauts, had produced some suggested changes. The review itself resulted in McDonnell's receiving 167 requests for alterations. MSC inspected the revised mock-up in November.


Gemini Engineering Mockup
Figure 37. Two McDonnell technicians examine the engineering mockup of the Gemini spacecraft, exhibited to 140 industry and NASA representatives in St. Louis on August 15-16, 1962. (McDonnell Photo D4E-257884, no date.)

August 16

The Air Force and NASA agreed to use a standard Atlas space booster for the Gemini program, sharing the development cost equally. Ground rules for the standard Atlas space booster (which was then being developed by the Air Force) were (1) no new development program, (2) rearranging equipment in the pad for standardization, (3) eliminating splices, (4) combining electrical installations, (5) minimizing differences between programs, and (6) incorporating ballistic missile to the Atlas space booster would require (1) a fully-qualified engine up-rated from 150,000 to 165,000 pounds of thrust, (2) elimination vernier rockets to lower use of propellants (3) standard tank pressures, (4) standard pneumatic pressures, (5) elimination of retrorockets, and (6) standard range safety package. The first standard vehicle was expected to be available in September 1963.

August 16

The Agena status displays were reviewed and eight were approved. These displays comprised seven green lights which, when on, indicated that various functions of the Agena were satisfactory. The eighth, a red light, would go on to indicate main engine malfunction. Gemini Project Office also approved the list of commands required to control certain Agena functions during rendezvous and docking maneuvers by the Gemini spacecraft. The primary mode of command transmittal was expected to be by radio. The Gemini commands to Agena were reviewed on September 13-14, resulting in a list of 34 minimum commands to be initiated from the spacecraft during the Gemini rendezvous maneuver.

August 27

Gemini Project Office initiated a program to coordinate and integrate work on developing Gemini rendezvous and long-duration missions. This program was handled by a mission-planning and guidance-analysis coordination group, assisted by three working panels.

August 28

At a spacecraft production evaluation meeting, Gemini Project Office and McDonnell revised the projected launch date of the first Gemini flight from August to September 1963. Delays in the delivery of components from vendors caused the revision. The first manned flight (second Gemini mission), however, was still scheduled for November.

August 31

Gemini Project Office outlined plans for checking out the spacecraft at Cape Canaveral. Gemini preflight checkout would follow the pattern established for Mercury, a series of end-to-end functional tests to check the spacecraft and its systems completely, beginning with independent modular systems tests. The spacecraft would then be remated for a series of integrated tests culminating in a simulated flight just before it was transferred to the launch complex. To implement the checkout of the Gemini spacecraft, the Hangar S complex at Cape Canaveral would be enlarged. Major test stations would be housed Hangar AR, an existing facility adjacent to Hangar S. The required facilities were scheduled to be completed by March 1, 1963, in time to support the check out of Gemini spacecraft No. 1, which was due to arrive at the Cape by the end of April 1963.


Facilities at Cape Canaveral
Figure 38. Proposed layout of Gemini facilities at Cape Canaveral. (McDonnell, "Project Gemini Engineering Mockup Review," Aug. 15-16, 1962, p. 163.)

August (during the month)

Rocketdyne completed designing and fabricating prototype hardware for both spacecraft liquid propulsion systems and initiated testing of the reaction control system. Test firing of the 25-pound-thrust chambers revealed nozzle erosion causing degradation in performance after one third the specified burn time.

September 1

George W. Jeffs became Program Manager of the Paraglider Development Program at North American. He replaced N. F. Witte, who remained as Assistant Program Manager. This organizational change reflected the elevation of work on paraglider from project to program status within North American's Space and Information Systems Division. The paraglider program achieved operating division status three months later when Jeffs was appointed Vice President of Space and Information Systems Division.

September 4

Gemini Project Office directed McDonnell to provide spacecraft No. 3 with rendezvous radar capability and to provide a rendezvous evaluation pod as a requirement for missions 2 and 3. Four pods were required: one prototype, two flight articles, and one flight spare.

September 5

For Gemini rendezvous missons, Manned Spacecraft Center intended to launch the Agena target vehicle first. If conditions were normal, the spacecraft would be launched the following day.

September 6

A study group formed at the Gemini mock-up review of August 15-16 met to review the ejection seat development program. McDonnell reported the successful completion of redesign and testing which cleared the way for resumption of off-the-pad developmental testing. McDonnell described the major outstanding design task as the determination of the dynamic center of gravity of the seat-man combination under expected acceleration profiles.

September 12

Simulated off-the-pad tests of the redesigned Gemini escape system resumed with test No. 6. Test No. 7 followed on September 20. Though primarily successful, these tests revealed some problems. The seat-structure thrust pad required reanalysis and redesign. Simulated off-the-pad testing was temporarily halted until a final configuration rocket catapult became available. A rocket motor test on January 4, 1963, demonstrated the structural integrity of the thrust-pad area, and simulated pad ejection tests resumed the following month.

September 14

A coordination meeting on mission planning and guidance defined the first Gemini mission as a spacecraft maximum-heating-rate test. As many spacecraft systems as possible were to be tested, to allow the second flight to be manned. A meeting between Manned Spacecraft Center and McDonnell on September 18 established the ground rules for the first mission: the trajectory was to be ballistic with a range of about 2200 miles; primary objective was to obtain thermodynamics and structures data; secondary objective was partial qualification of spacecraft systems.


Figure 39. Planned sequence of events for a Gemini mission. (McDonnell, "Project Gemini Engineering Mockup Review," Aug. 15-16, 1962, p. 23.)


Figure 40. McDonnell's proposed sequence of events for the first Gemini mission. (McDonnell, "Project Gemini Mission Plan, Spacecraft No. 1," Sept. 14, 1962, p. 7.)

September 17

At the University of Houston's Cullen Auditorium, Director Robert R. Gilruth of Manned Spacecraft Center (MSC) introduced the nine men who had been selected for the MSC flight crew training program for Gemini and Apollo flights. Of the nine, four were from the Air Force, three were from the Navy, and two were civilians. From the Air Force were Major Frank Borman and Captains James A. McDivitt, Edward H. White II, and Thomas P. Stafford. The Navy volunteers were Lieutenant Commanders James A. Lovell, Jr., and John W. Young, and Lieutenant Charles Conrad, Jr. The two civilians were Neil A. Armstrong and Elliot M. See, Jr.

September 19

ACF Electronics delivered an engineering prototype radar beacon to McDonnell. An engineering prototype C-band beacon had operated at ACF Electronics under simulated reentry conditions with no degredation in performance.

September 19

Life Systems Division reported on continuing studies related to extravehicular operations during Gemini missions. These included evaluation of a superinsulation coverall, worn over the pressure suit, for thermal protection; ventilation system requirements and hardware; and methods of maneuvering in proximity to the spacecraft.

September 25

A preliminary design criteria review conference for complex 14, held in Los Angeles, resulted in ground rules for all contractors. Target dates established were (1) stand availability, July 1, 1963; (2) estimated beneficial occupancy date, November 1, 1963; and (3) vehicle on-stand date, February 1, 1964. Complex 14 would be used for launching the Gemini-Agena target vehicle and Mariner spacecraft, but basic modifications would be primarily for the Gemini program. On November 15, 1962, Air Force Space Systems Division reviewed the criteria summary report for complex 14 modifications and suggested only minor engineering changes.

October 1

Air Force Space Systems Division revised the Development Plan for the Gemini launch vehicle. The budget was raised to $181.3 million. Cost increases in work on the vertical test facility at Martin's Baltimore plant, on the conversion of pad 19 at Cape Canaveral, and on aerospace ground equipment had already generated a budget increase to $172.6 million during September. The new Development Plan also indicated that the first launch date had slipped to December 1963.

October 3

Manned Spacecraft Center (MSC) published the Gemini Program Instrumentation Requirements Document (PIRD), the basis for integrating the world-wide Manned Space Flight Network to support the Gemini program. In compiling PIRD, MSC had received the assistance of other NASA installations and Department of Defense components responsible for constructing, maintaining, and operating the network.

October 3

At a mechanical systems coordination meeting, McDonnell presented its final evaluation of the feasibility of substituting straight tube brazed connections for threaded joints as the external connections on all components of the spacecraft propulsion systems. McDonnell had begun testing the brazing process on June 26, 1962. Following its presentation, McDonnell was directed to make the change, which had the advantages of reducing leak paths and decreasing the total weight of propulsion systems.

October 5

McDonnell and Lockheed reported on radiation hazards and constraints for Gemini missions at a Trajectories and Orbits Coordination meeting. McDonnell's preliminary findings indicated no radiation hazard for normal Gemini operations with some shielding; with no shielding the only constraint was on the 14-day mission, which would have to be limited to an altitude of 115 nautical miles. Lockheed warned that solar flares would pose a problem at higher altitudes. Lockheed also recommended limiting operations to under 300 miles pending more data on the new radiation belts created by the Atomic Energy Commission's Project Dominic in July 1962.

October 12

Associate Director Walter C. Williams of Manned Spacecraft Center (MSC) invited top-level managers from all major government and contractor organizations participating in the Gemini program to become members of a Project Gemini Management Panel. These invitations had arisen from discussions between Williams and MSC Director Robert R. Gilruth on the inevitable problems of program management and technical development. The panel, chaired by George M. Low, Director, Spacecraft and Flight Missions, Office of Manned Space Flight, met first on November 13, 1962. In addition to NASA and Air Force representatives, the panel membership included vice presidents of McDonnell, Martin, Aerospace, Aerojet-General, and Lockheed. A similar development-management structure had worked well in Project Mercury, minimizing delays in communication and providing fast reactions to problems.

October 15

NASA awarded a contract to International Business Machines Corporation to provide the ground-based computer system for Projects Gemini and Apollo. The contract cost was $36,200,018. The computer complex would be part of the Integrated Mission Control Center at Manned Spacecraft Center, Houston.

October 19

Wesley L. Hjornevik, Manned Spacecraft Center (MSC) Assistant Director for Administration, described to members of MSC's senior staff the implications of NASA Headquarters' recent decision to cut the MSC budget for fiscal year 1963 from $687 million to $660 million, the entire reduction to be borne by the Gemini program. Hjornevik feared that the Gemini budget, already tight, could absorb so large a cut only by dropping the paraglider, Agena, and all rendezvous equipment from the program. Gemini Project Office (GPO) reported that funding limitations had already forced Martin and McDonnell to reduce their level of activity. The first Gemini flight (unmanned) was rescheduled for December 1963, with the second (manned) to follow three months later, and subsequent flights at two-month intervals, with the first Agena (fifth mission) in August or September 1964. This four-month delay imposed by budget limitations required a large-scale reprogramming of Gemini development work, reflected chiefly in drastic reduction in the scale of planned test programs. Details of the necessary reprogramming had been worked out by December 20, when GPO Manager James A. Chamberlin reported that December 1963 was a realistic date for the first Gemini flight. Gemini funding for fiscal year 1963 totaled $232.8 million.

October 25

Manned Spacecraft Center informed Lockheed that Gemini program budget readjustments required reprogramming the Gemini-Agena program. Subsequent meetings on November 2 and November 20 worked out the changes necessary to implement the Agena program at minimum cost. The overall test program for the Agena and its propulsion systems was significantly reduced, but in general neither the scope nor the requirements of the Agena program were altered. The major result of the reprogramming was a four-month slip in the scheduled launch date of the first Agena (to September 1964); this delay was about a month and a half less than had been anticipated when reprogramming began. In addition, Lockheed was to continue its program at a reduced level through the rest of 1962, a period of about six weeks, and to resume its normal level of activity on January 1, 1963.

October 31

The apogee of the basic spacecraft orbit model was set at 167 nautical miles, the perigee of the elliptical orbit at 87. The altitude of the circular orbit of the target vehicle was to be 161 nautical miles.

October (during the month)

Minneapolis-Honeywell delivered two engineering prototype attitude control and maneuver electronics systems to the prime contractor. McDonnell installed one of these systems in the electronic systems test unit (ESTU) and conducted subsystems compatibility checks, using the prototype horizon scanners. The ESTU was a simplified spacecraft mock-up with provisions for monitoring all electronic components in their flight locations. Testing began on November 19.

November 5

Goddard Space Flight Center announced the award of contracts totaling approximately $12 million to modify NASA's Manned Space Flight Tracking Network to support long-duration and rendezvous missions. The contracts were with the Canoga Electronics Corporation, Van Nuys, California, for the tracking antenna acquisition aid system ($1.045 million); Radiation, Inc., Melbourne, Florida, for digital command encoders ($1.95 million); Collins Radio Company, Dallas, Texas, for the radio frequency command system ($1.725 million); and Electro-Mechanical Research, Inc., Sarasota, Florida, for the pulse code modulation system ($7,376,379).

November 6

B. F. Goodrich delivered a prototype partial-wear, quick-assembly, full-pressure suit to Manned Spacecraft Center (MSC) for evaluation by Life Systems Division. The partial-wear feature of this suit, demanded by the long-duration missions planned for the Gemini program, comprised detachable suit components (sleeves, legs, helmets). This was the second of two partial-wear suit prototypes called for by the original contract; but MSC had, in the meantime, requested B. F. Goodrich to provide 14 more suits based on this design. The additional suits varied only in size; they were to follow the design of the prototype according to the spacifications of October 10, 1962. The prototype, originally designated G-2G, became G-2G-1 and the remaining suits were designated G-2G-2 through G-2G-15. MSC requested extensive design changes after evaluating G-2G-1 and several other suits. The final model was G-2G-8, delivered to MSC on January 21, 1963. It was later rejected in favor of a suit designed by David Clark Company, Inc., Worcester, Massachusetts, which incorporated B. F. Goodrich helmets, gloves, and additional hardware.


Pressure Suit
Figure 41. The B. F. Goodrich partial-wear full-pressure suit being developed for the Gemini program. (B. F. Goodrich Aerospace and Defense Products, "Design, Development, and Fabrication of Prototype Pressure Suits, Final Report," Feb. 1, 1965, p. 10.)

November 9

Sled ejection test No. 1 was conducted at Naval Ordnance Test Station. Despite its designation, this test did not call for seats actually to be ejected. Its purpose was to provide data on the aerodynamic drag of the test vehicle and to prove the test vehicle's structural soundness in preparation for future escape system tests. The test vehicle, mounted by boilerplate spacecraft No. 3 (a welded steel mock-up of the Gemini spacecraft aerodynamically similar to the flight article), was a rocket-propelled sled running on tracks. Although test objectives were achieved, the boilerplate spacecraft was severly damaged when one of the sled motors broke loose and penetrated the heatshield, causing a fire which destroyed much instrumentation and equipment. Despite repairs required for the boilerplate and major modification or rebuilding of the sled, Gemini Project Office foresaw no delay in the sled test program.

November 16

Andre J. Meyer, Jr., of Gemini Project Office reported that Space Technology Laboratories was conducting a study for NASA Headquarters on a "T-back" pod to be used in the spacecraft adapter as the rendezvous target instead of the Agena. The pod would be stabilized but would have no translation capabilities. Although it would be almost as expensive as the Agena, it would avoid separate launch problems.

November 21

At a mechanical systems coordination meeting, representatives of McDonnell and Manned Spacecraft Center decided to terminate McDonnell's subcontract with CTL Division of Studebaker for the backup heatshield. The decision resulted from growing confidence in the new McDonnell design as well as from CTL problems in fabricating heatshield No. 1. Termination of the CTL contract would save an estimated $131,000.

November 30

Gemini Project Office identified the primary problem area of the spacecraft liquid propellant rocket systems to be the development of a 25-pound thruster able to perform within specification over a burn time of five minutes. Three-minute chambers for the reaction control system (RCS) had been successfully tested, but the longer-duration chambers required for the orbit attitude and maneuver system (OAMS) had not. Rocketdyne was three weeks behind schedule in developmental testing of RCS and OAMS components, and five weeks behind in the systems testing.

November 30

Gemini Project Office reported revised facilities plans for implementing the preflight checkout of the Gemini spacecraft at Cape Canaveral. Project Gemini facilities were no longer to be wholly contained in the Hanger S complex on Cape Canaveral. Schedule changes and the elimination of incompatibilities between Apollo and Gemini spacecraft fuel-oxidizer and cryogenic systems made feasible the integration of Gemini facilities with the Apollo facilities planned for construction on Merritt Island. The first two Gemini spacecraft would be checked out in Hanger AF (as previously planned), but as soon as the Merritt Island facilities were complete the entire preflight checkout operation would shift to Merritt Island. The Merritt Island facilities were scheduled to be completed in the first quarter of 1964.


MSC Facilities at Cape Canaveral
Figure 42. Location of Manned Spacecraft Center facilities at Cape Canaveral and Merritt Island. (NASA, "Manned Spacecraft Center Atlantic Missile Range Operations, 1959-1964 Facilities," Apr. 15, 1963.)

November (during the month)

During the first three weeks of the month, Air Force Space Systems Division and Martin-Baltimore negotiated the terms of the contract for Phase I of the Gemini launch vehicle program. The resulting cost-plus-fixed-fee contract included an estimated cost of $52.5 million and a fixed fee of $3.465 million. This contract covered the development and procurement of the first launch vehicle and preparations for manufacturing and procuring the remaining 14 vehicles required by the Gemini program.

December 10

North American began deployment flight testing of the half-scale test vehicle (HSTV) in Phase II-A of the Paraglider Development Program. The HSTV was carried aloft slung beneath a helicopter. The main purpose of the deployment flight tests was to investigate problem areas in the transition from release of the rendezvous and recovery canister to glide - the ejection, inflation, and deployment of the paraglider wing. The first flight partially substantiated the feasibility of the basic deployment sequence, but emergency recovery procedures were necessary. In the second test (January 8, 1963), the sail disintegrated, and in the third (March 11), the rendezvous and recovery canister failed to separate. In both instances, attempts to recover the vehicle with the emergency system were thwarted when the main parachute failed to deploy, and both vehicles were destroyed on impact.


Paraglider Flight Test
Figure 43. Gemini paraglider half-scale test vehicle slung beneath an Army helicopter at the beginning of the second deployment flight test. (NAA-SID Photo 277/4, Jan. 4, 1963.)

December 10-11

Representatives of Manned Spacecraft Center, NASA Headquarters, Flight Research Center, Langley Research Center, and Ames Research Center conducted a Design Engineering Inspection of the full-scale test vehicle (FSTV) for Phase II-A of the Paraglider Development Program. As conceived during Phase I of the program, the FSTVs (the contract called for two) were to be a means of meeting a twofold objective: (1) the development of systems and techniques for wing deployment and (2) the evaluation of flight performance and control characteristics during glide. After reviewing flight test objectives, test vehicle hardware, and electrical and electronic systems, the inspecting team submitted 24 requests for alterations to North American.

December 14

A 10-percent fluctuating-pressure model of the Gemini spacecraft completed its exit configuration test program in the mach number range of 0.6 to 2.5, the region of maximum dynamic pressure. On January 15, 1963, a Gemini spacecraft dynamics stability model also completed its test program providing dynamic stability coefficients for the spacecraft reentry at mach numbers 3.0 to 10. These tests completed all the originally scheduled wind tunnel testing for Project Gemini; however, three additional test programs had been initiated. These included additional testing of the spacecraft 20-percent ejection seat model, testing of the astronaut ballute model to obtain data for design of the astronaut stabilization system, and testing of the rigid frame paraglider model to determine optimum sail configuration.


Wind tunnel model of Gemini spacecraft
Figure 44. The 10-percent model of the Gemini spacecraft used in wind tunnel testing at McDonnell. (McDonnell Photo D4E-250564, undated.)

December 17

The newly formed Scientific Experiments Panel met to solicit proposals for scientific experiments to be performed on Gemini and Apollo flights. The panel was a Manned Spacecraft Center organization whose function would be to receive, evaluate, and implement these proposals.

December 19

Titan II flight N-11, the eighth in a series being conducted by the Air Force to develop the weapon system, was launched from Cape Canaveral. It carried a design change intended to reduce the amplitude of longitudinal oscillations which had appeared during first stage operation on all seven previous Titan II flights. This phenomenon, which subsequently became known as POGO, generated g-forces as high as nine in the first stage and over three at the position on the missile corresponding to the location of the spacecraft on the Gemini launch vehicle. Fearing the potentially adverse effect on astronaut performance of such superimposed g-forces, NASA established 0.25g at 11 cycles per second as the maximum level tolerable for Gemini flights. As a first try at solving the POGO problem, Titan II N-11 carried standpipes in each leg of the stage I oxidizer feed lines to interrupt the coupling between the missile's structure and its propulsion system. This coupling was presumed to be the cause of the instability. Postflight analysis, however, revealed that the POGO fix was unsuccessful; longitudinal oscillation had actually been multiplied by a factor of two.

December 26

Air Force Space Systems Division established the Gemini Launch Vehicle Configuration Control Board to draw up and put into effect procedures for approving and disapproving specifications and engineering change proposals for the Gemini launch vehicle. It formally convened for the first time on March 5, 1963.

December (during the month)

Air Force Space Systems Division and Aerojet-General negotiated a cost-plus-fixed-fee contract for the first phase of the Gemini launch vehicle engine program, February 14, 1962, through June 30, 1963. The contract required delivery of one set of engines, with the remaining 14 sets included for planning purposes. Estimated cost of the contract was $13.9 million, with a fixed fee of $917,400 for a total of $14,817,400.


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