satellite services, such as improved communications for surface vessels. These studies will provide an understanding of the degree to which satellite systems can meet maritime requirements.

This year, the National Oceanic and Atmospheric Administration requested NASA's assistance to determine the potential role of satellites in meeting needs for nation-wide disaster warning. Hurricanes, earthquakes, tornadoes, forest fires, floods, epidemic and transportation catastrophies have local and regional effects. Timely warning might significantly reduce the costs to life and property. A satellite system appears feasible within this decade to relay warning data directly to inexpensive home receivers, routing messages to each of the fifty states or to smaller regions as appropriate. These are examples of the types of studies we undertake to determine the technology, the subsystems and space systems which we should develop. Let me now turn to a discussion of the principal spacecraft program we use to develop and test these systems and occasionally even to provide operational data-the series of Applications Technology Satellites (ATS).

Applications technology satellites

The ATS program is dedicated to the development and flight test of technology not only for communications, but also for meteorology, navigation, tracking and data relay, and educational television experiments such as the one we have planned with India.

After we completed our test program with ATS 1 and 3 successfully, we offered their use to the whole user community for experiments to demonstrate new applications and provide experience in satellite use. A number of organizations have participated in these user experiments. For example, the State of Alaska has transmitted educational material consisting of TV and voice radio via ATS 1. From June to December 1970, equipment checkout and link testing have been carried out by Alaska totaling 108 hours of satellite use.

The Corporation for Public Broadcasting has completed an experiment in transcontinental interconnection by transmitting television program material from the East to the West Coast via satellite and conventional surface means in parallel. The received signals were compared and the satellite signals rebroadcast on two occasions by station KCET in Los Angeles. The experiment confirmed that acceptable quality TV pictures can be distributed via satellite to ground stations which are located in an urban environment and are smaller and cheaper than those required by the INTELSAT system. The Corporation gained valuable experience in overcoming operating problems associated with such distribution.

Other user tests with ATS 1 and 3 have included medical communications between NIH and the University of Wisconsin, educational communications between Stanford University and Brazil, maritime communications with the Netherlands Coast Guard, and aircraft communications with the U.K. Royal Aircraft Establishment. Progress with our user requirements studies leads us to anticipate new and expanded opportunities.

NOAA continues quasi-operational use of ATS 1 and 3, receiving data from the 2000-line camera on each satellite at their Wallops Island, Virginia facility. This provides NOAA with a source of data from synchronous orbit which is useful for observation of short-term weather phenomena as shown in the chart (SC70-224 rev). Recent correspondence from NOAA cites nine specific contributions of these pictures to accurate and timely predictions of severe storms over the areas shown in the next chart (SC71–2006).

Results from the aeronautical L-band experiment on ATS 5 have been of special interest. Equipment working with the L-band transponder on ATS 5 was carried aboard the SS Manhattan in the spring of 1970 on a voyage through the Northwest Passage. Results of tests in teletype transmissions and ranging were generally excellent, even at the worst look-angles and path-lengths. Comparative receiving tests were also conducted in the equatorial zone. The results confirm the desirability of L-band for aeronautical and marine navigation and traffic control. The ATS 5 experiment which measures precipitation losses at millimeter frequencies has also provided data of value to our technical consultation activities which I will describe later. This part of the spectrum appears usable for space broadcasting. The possibility of completing the original ATS 5 mission has led us to study the feasibility of despinning ATS 5 by remote control using a satellite which could observe ATS 5 by television, rendezvous and dock with it, despin it, and then un-dock, prior to using the same satellite to observe the deployment of the ATS-F unfurlable antenna.

In-house and contractual studies of the feasibility of this experiment indicate that it is feasible using adaptations of already developed technology. It would provide valuable information on the behavior of large, deployable structures such as the ATS-F antenna, and would be a step in the application of remotecontrol manipulator techniques for real-time operations in space. Teleoperators can augment man's remote effectiveness, performing work that is hazardous, beyond man's physical capability, or which man would ordinarily perform inefficiently. The experiment could prove a first step toward development of a capability for remote-controlled repair and refurbishment in orbit, possible recovery of automated satellites, or perhaps resupply of manned spacecraft. Study of the implications seems attractive.

ATS-F and G

The major current mission of the Communications Programs is the development of ATS-F and G. These spacecraft will be appreciably larger than the earlier ATS spacecraft (SC71-2007), weighing about 2500 pounds in orbit. Fairchild-Hiller Corp. has the contract for construction of the flight equipment under the direction of the GSFC.

The technical objectives of the ATS-F and G are to space test a thirty-foot diameter deployable antenna with good performance at frequencies up to 6 GHz; point the antenna and spacecraft with an accuracy of 0.1 degree; space test precision attitude measuring technology; and provide a high gain steerable antenna at synchronous altitude for advanced space application concepts.

Because of its capability to produce powerful, highly directional television signals, the large-aperture antenna will be applicable to improved mass instruction broadcasting in developing areas as well as to tracking and communicating with lower-altitude satellites. It will also permit accurate measurements of surface sources of ratio interference to satellite communications.

ATS-F and G will both carry additional applications experiments which make use of and require the basic capability and technology of the spacecraft. Experiments for ATS-F have been selected as follows and are detailed in my full statement:

tracking and data acquisition experiment to track and receive telemetry from and transmit commands to NIMBUS E;

ATS F&G CHARACTERISTICS

WEIGHT:

ANTENNA DIAMETER:

2500 POUNDS 30 FEET 50 FEET

MAXIMUM DIMENSION:

END OF LIFE POWER: 400 WATTS

POINTING ACCURACY:

0.1°

ORBIT:

LAUNCH VEHICLE:

LAUNCH DATES:

GEOSTATIONARY

TITAN IC 1973 & 1975

aeronautical communications and traffic control experiment to provide a transponder on ATS-F operating in the aeronautical L-band for multiplechannel communications and position-location tests with aircraft. The recent policy determination by the Office of Telecommunications Policy to have the government use L-band for aeronautical satellite services will increase the value of this experiment;

propagation and communications experiments in the millimeter wave frequency bands;

radio frequency interference experiment to measure interfering signals originating on the visible Earth in the communication satellite frequency bands;

high resolution infrared camera experiment to observe thermal changes of the Earth's surface and atmosphere in close time sequence and provide night viewing capability; and

some seven scientific experiments to measure particle flux and direction and the behavior of the Earth's magnetic field.

A laser communications experiment originally selected and planned for ATS-F ran into technical difficulties too severe to overcome within schedule and cost constraints and has been removed from the payload complement. It is being considered for flight on ATS-G.

Promising experiment proposals for ATS-G have been received in high power transmitting tubes, laser propagation and communications, radar sea state measurement, and high resolution atmospheric sounding. Their selection will include coordination across program disciplines to optimize the total experiment package.

After launch, ATS-F will be maintained over the U.S. for about 12 months to permit full data acquisition from its experiments. Then it will be moved to 35° E. longitude for a cooperative instructional television experiment with India and cooperative experiments with other countries as described more fully in my statement for the record.

That is the status of NASA's current ATS program. Now let me touch briefly on our cooperative Applications Satellite (CAS) program in which we supplement on a cost-shared basis-the main thrust of our technology development and test efforts.

Cooperative application satellites

CAS-A is a cooperative program with the French Space Agency. Centre Nationale D'Etudes Spatiales (CNES). Project objectives are to obtain scientific data on wind speed and direction, air temperature, and air pressure at 45,000 foot altitude and to develop and demonstrate satellite and balloon technology for range and range-rate measurements to locate balloon position. The CAS-A satellite, being developed and funded by France, is proceeding well toward a launch from Wallops Island in the third quarter of 1971. NASA's contribution consists of the Scout launch and technical and scientific consultation.

The second cooperative project, CAS-C, is an outgrowth of an earlier, cooperative, scientific project with the Government of Canada, the International Satellites for Ionospheric Studies (ISIS) program. The success of ISIS led to the substitution of a Communications Technology Satellite for the last of the projected ISIS spacecraft. We have worked with the Canadian Department of Communications (CDC) during 1970 to define the experiment payload. The Government of Canada has approved the program, and expects to fund about 80% of the total program costs.

The overall objective of the CAS-C/CTS is to advance the state of the art in spacecraft and related ground-based technologies relevant to broadcasting, remote-area communications, and other satellite systems. The CAS-C mission includes development, demonstration and flight test of communications experiments at 12 and 15 GHz, and spacecraft technology and user experiments of importance to both countries.

Under the agreement, NASA will develop and test a 200 watt, super-efficiency, 12 GHz transmitter tube. The tube development, its associated power conditioning equipment, the launch vehicle and spacecraft environmental testing will be funded by NASA. Canada will be responsible for the balance of the experiments, spacecraft design, fabrication, integration and systems testing. The Canadian experiments will include an unfurlable light-weight solar array of over 1 kw capacity, liquid metal slip rings, electric-propulsion station-keeping thrusters,

and an accurate stabilization system for satellites with flexible appendages. After launch from the Eastern Test Range by NASA, the U.S. and Canada will conduct experiments directed toward demonstrating a broad spectrum of services for small villages on a time-shared basis.

Mission studies for future technology flight programs

During 1970 we started advanced mission studies for an ATS-H class of spacecraft, which we are considering for a possible first launch in 1976 or 1977. The principal mission objective will be space technology necessary for future information networks, such as the Biomedical Communication Network discussed earlier, including the technologies of high power and multiple beams for multiple-link communications to a wide distribution of small users. ATS-H will test the technologies of combined shaped-beam and multiple-beam antennas required to provide coverage to irregularly shaped geographic areas and to provide highly directive links to small user terminals.

The bandwidth required to meet the future demand for information networks forces us to the 11.7 to 12.2 GMz band, and the tradeoff between ground station costs and satellite transmitter costs suggests the need for superefficient transmitting devices with power outputs in excess of 1 kw. These power levels require high-power, high-voltage power supplies.

We are also conducting advanced mission studies of small, standardized spacecraft which could be dedicated to quick, economical flight test of single experiments in order to overcome the four-year lead time experienced between selection and flight on an observatory-class satellite. These Small Applications Technology Satellites (SATS) would be Scout- and Delta-class spacecraft having standardized designs and specified experiment interfaces. Our goal is to be able to accept experiment hardware, integrate it with a spacecraft and launch within approximately six months of flight go-ahead.

Experiments being developed in our Advanced Applications Flight Experiment (AAFE) program will provide us with an inventory of designed experiments from which we can select flight payloads either for ATS or SATS missions, depending on their size, development schedule, or need for combination with other experiments.

We are also continuing our Tracking and Data Relay Satellite studies in concert with NASA's Office of Tracking and Data Acquisition, and in coordination with DoD. Under an agreement with DoD, NASA has responsibility for low and medium data-rate systems and technology. We will initiate two parallel study contracts on such systems this spring, with an expected completion date of early 1972.

Air Traffic Control Satellites

In late 1970 the Office of Telecommunications Policy (OTP) reviewed the projected requirements for air traffic communications, navigation and air traffic control and considered the capability of existing technology and space flight systems to meet those requirements. On January 7 that office issued a Statement of Government Policy on Satellite Telecommunications for International Civil Aviation Operations, committing our nation to a new satellite application in aeronautical and maritime communications and traffic control. That policy statement recognized the primary responsibility of the Department of Transportation (DOT) to establish the preoperational and operational systems to serve the airlines and NASA's role to support DOT as required and to conduct general research and development activities in this area.

The ability of the Government to make this policy determination was largely provided by the general research and development conducted by NASA in the ATS series.

DOT has the responsibility for defining the requirements, program budgeting, and management of pre-operational and operational systems activity. It is NASA's job to support the DOT in joint studies which will assess the technical approaches and cost effectiveness of commercial proposals for preoperational services. Our efforts will include in-house and contractor support studies.

Radio Interference and Propagation Program (RIPP)

As society, industry, and technology advance, increasing use is made of radio transmission for communications. The advent of communications satellites in the early 1960's added a new dimension to the uses of radio, permitting new applications but also creating a new demand for the limited Radio Frequency (RF) spectrum. Regulation of use of the RF spectrum is the responsibility of