electrical power and telemetry systems, and the spacecraft command recorder and decoder subsystems; major modifications in the propulsion system; and addition of the docking adapter and shroud.

The main engine is being given a multiple restart capability so that it may be started as many as five times in orbit for rendezvous and postrendezvous maneuvers. A secondary propulsion system is also being added to provide small velocity changes and propellant orientation for main engine start. The docking capability is achieved by adding to the AGENA an adapter, built by McDonnell, and provided as Government-furnished equipment to Lockheed.

GEMINI LAUNCH FACILITY

In 1963 an extensive program was completed for modifying an existing TITAN launch pad, launch complex 19 (fig. 16), for all GEMINI spacecraft. Modifications are presently underway on the old MERCURY launch pad, launch complex 14, to accommodate the ATLAS-AGENA, which will be the GEMINI target vehicle utilized for rendezvous operations. The Air Force is funding this project, and the work is progressing on schedule. Construction started in September of 1962 and will be completed by the end of 1964, in plenty of time to meet the ATLAS-AGENA launch schedule.

PROJECT APOLLO

The APOLLO program is evolving rapidly. The years of 1961 and 1962 (fig. 17) involved decisionmaking and 1963 contracting and beginning of the development and manufacture phase. In 1964, further progress will be made in this phase. The year 1965 will be one of testing, and in 1966 we will begin the flight program.

The ultimate objective of the APOLLO program is to achieve U.S. preeminence in space by landing men on the Moon and returning them safely to Earth in this decade. This accomplishment will provide the United States with a broad foundation of operational capability in space and the associated technology; a valuable complex of developmental, test and operational support facilities; and a trained Government and industrial team. All will open the door to the further exploration of space.

Specific APOLLO objectives are shown here (fig. 18). Unmanned orbital flights

First, before it is safe to commit a man to flight, the spacecraft and launch vehicle must be qualified in unmanned orbital flights. In these flights, the following will be verified: performance of the SATURN IB launch vehicle, including guidance and control operation and structural integrity; the structural integrity and compatibility of the spacecraft and adapter in relation to the launch

SPECIFIC APOLLO OBJECTIVES

UNMANNED ORBITAL QUALIFICATION-APOLLO SPACECRAFT/SATURN IB

MANNED ORBITAL FLIGHTS

a. LONG DURATION MISSION

b. RENDEZVOUS AND DOCKING

UNMANNED ORBITAL QUALIFICATION APOLLO SPACECRAFT/SATURN V
MANNED LUNAR FLIGHT

a. ORBITAL LUNAR MISSION SIMULATION

b. LUNAR MISSIONS

NASA M64-794

FIGURE 18

vehicle; the satisfactory firing and restarting of the spacecraft engines and the safe recovery of the spacecraft command module; and the capability of the guidance and control system to perform entry at earth orbital speeds. When unmanned flight testing has progressed to the point where it is safe for men to orbit the earth in the APOLLO spacecraft, the second major flight objective, that of manned Earth orbital flights, will be pursued.

Manned orbital flights

Manned Earth orbital flights will be conducted in two major phases. In the first phase, only the command and service module portion of the spacecraft will be manned, in the long duration, 14-day mission. Both crew and equipment will be exposed to the rigors of the space environment, and the equipment reliability essential to a lunar mission will be demonstrated.

An unmanned lunar excursion module (LEM) will be remotely controlled and evaluated by the astronauts in the command module for the purpose of checking operation of the LEM systems and performance of the descent and ascent engines after exposure to space vacuum and temperature. Rendezvous and docking of the command and service module spacecraft with the unmanned LEM will be accomplished.

Successful completion of these tests will make it possible to proceed to the second phase of manned Earth orbital tests, in which rendezvous and docking operations will be perfected. The LEM engines will be fired by the astronauts; the guidance system and rendezvous trajectories will be checked; and docking maneuvers will be demonstrated as the manned LEM moves out in space away from the command module and then comes back to rendezvous and dock. Finally, the necessary ground network support system will be verified.

Unmanned orbital qualification

In unmanned orbital qualification, final flight tests of the complete lunar space vehicle will be performed. Unmanned reentry will be demonstrated to verify the spacecraft heat shield. Tracking and communication networks will be exercised in unmanned lunar mission trajectories.

Manned lunar flights

Manned Earth orbital flights will first be conducted with a complete fully manned lunar space vehicle in a simulation of the lunar mission. All phases of crew and equipment performance will be tested. Manned circumlunar flights to perfect operational techniques and to test the satisfactory operation of all systems will be conducted. The first manned lunar landing will then be made.

SYSTEMS ENGINEERING

Systems engineering effort is basic to the success of the program. It provides programwide technical analysis and guidance to insure that the functional and performance requirements placed on all elements of the APOLLO system are within the present or projected state of the art and can be developed within the scope of the program. The bulk of systems engineering on all elements of the program is done at the centers. We maintain a technical competence in systems engineering within manned space flight. This competence is concentrated on overall systems that interface more than one center.

We have considerable analytic work underway in the study of flight trajectories of all phases of the mission to determine the interactions of vehicle weights, fuel consumption, guidance and navigation characteristics, and to allow for the establishment of alternate or emergency mission profiles. Included in this work is an investigation of the effects of selecting a particular lunar landing site and of particular lunar lighting conditions on hardware requirements.

A portion of our effort is devoted to undertaking special investigation to review specialized areas such as guidance and navigation, propulsion systems, fuel cells for the production of electric power, and environmental control systems.

Systems engineering also analyzes and synthesizes the communications and tracking facilities that will be required on the vehicle and on the ground. For example, initial studies have been completed on the shipborne facilities requirements for operation with the launch vehicle and spacecraft during the earth orbital phases of the missions. Study is also being made to determine whether or not a common frequency band and common electronic equipment should be used to provide for near-earth as well as deep-space communications. This would offer an opportunity to reduce the weight of the space vehicle equipment.

In quite a different field, we are continually studying APOLLO requirements related to the natural space environment. Among the areas considered in this study are: lunar topography, including large and small scale roughness and possible bearing strength; the determination and prediction of possible levels of radiation to be expected from solar flares; and the micrometeoroid problem.

The manned space flight organization in the past year has issued comprehensive specifications for the functional and performance re

quirements of the major system elements. These specifications have treated such items as the launch vehicle and spacecraft propulsion systems, guidance, navigation, control, space vehícle and ground communications and tracking facilities, life support systems, and ground and in-flight checkout requirements. Systems engineering continually reviews these specifications to be sure that they incorporate the results of the latest study and analysis and that they reflect the current status of hardware development.

On behalf of an effective weight control program, we have established control and design goal weights for all vehicle stages and spacecraft modules. The control weights are the maximum weights consistent with the APOLLO mission; design goal weights are desirable program goals. The latter are used to determine specification weights, which are enforced upon the contractors.

The second step in the weight control program is to make sure that contractors meet specification weights. For this purpose, we have initiated an advanced system of weight accounting and reporting. Last June we put into effect a NASA mass properties standard, which not only standardizes the weight reporting of the contractors, but also supplies information which allows us to make future weight predictions so that we can solve weight growth problems before they become critical.

Let us turn to some specific examples of systems engineering effort. Early in the program, systems engineering played a major role in the selection of the mission mode to be followed. The lunar orbit rendezvous mode was finally chosen because it provides advantages in schedule, cost, and development simplicity while maintaining probabilities of mission success and crew safety that are equal to, or better than, those of the other modes studied.

In this mode, the spacecraft, which includes a command module, a service module, and a lunar excursion module (LEM), will be launched through an Earth parking orbit into a lunar transfer trajectory by the three-stage SATURN V launch vehicle. Some 72 hours later, the service module propulsion system will deboost_the spacecraft into an orbit some 80 miles above the lunar surface. Two of the three astronauts will transfer from the command module to the lunar excursion module, which will separate from the remainder of the spacecraft and descend to a preselected area on the lunar surface. The third crew member will remain in the command module orbiting the Moon.

After lunar exploration, the two crew members will ascend in one of the two stages of the LEM on a trajectory that will permit rendezvous with the orbiting command module. After the crew has transferred to the command module, the LEM will be jettisoned and the command module will be returned to the vicinity of the Earth by again using the service module propulsion system. The service module itself will be jettisoned prior to the reentry of the command module into the Earth's atmosphere. The command module will be slowed for a safe landing on water or land by aerodynamic braking and, in the final phase, by parachute deployment.

SPACE VEHICLES

The space vehicles that will be used to achieve the above objectives are shown here (fig. 19). The SATURN I space vehicle consists