The purpose of this post is to provide access to documentation regarding SYNCOM for those who wish to learn more about this early Hughes satellite project.

The NASA Press Release dated 8/11/61 announcing the SYNCOM project is presented below.

A further NASA press release, dated 10/8/61, that provides details of the satellite design and operation is shown below.

Links are provided to the following SYNCOM documentation:

NASA Technical Report TR R-233 Volume I “SYNCOM Engineering Report” describes the SYNCOM II satellite and its subsystems, the communications ground stations, the telemetry and control ground stations, and reports upon the satellites first 150 days in orbit.

NASA Technical Report TR R-252 Volume II “SYNCOM Engineering Report” covers the launch of the SYNCOM III satellite, its performance during the first 100 days in orbit, the televising of the 1964 Summer Olympic Games and various communications tests conducted.


Commercial Communications Satellite, January 1960

Editor’s note:  The Hughes Report presented below along with the attached NASA commentary can be found in NASA SP-4407, Volume III, 1995.

By the end of 1959, Harold A. Rosen and his team had reworked their initial mid-1959 design for a geosynchronous communications satellite into a form that was very close to what was actually first launched as Syncom 1 in 1963. This report describes that design; only relevant excerpts appear here. The report anticipated a NASA program for communications satellite research and development that might provide a source of funding to Hughes for developing the satellite; however, NASA first chose to support a lower orbit satellite proposed by RCA called Relay. During discussions with NASA in 1960, the space agency suggested to Hughes the use of a larger Thor Delta booster rather than the Scout booster specified in this report. This would allow the satellite to be launched from Cape Canaveral in Florida rather than the Jarvis Island launch site discussed in the report.

Commercial Communications Satellite 

Report RDL/B-1, Engineering Division

H.A. Rosen and D.D. Williams,

Hughes Aircraft Company

January 1960.



This document describes an inexpensive communication satellite system for inter- continental transmission of television, telephonic, and teletype messages on a commercial basis.

The system proposed uses an active repeater in a satellite having a circular orbit in the plane of the earth’s equator with a period of 24 hours. Such a satellite is generally recognized as the ultimate communication satellite because it remains stationary to the earth.  The NASA has a program which is expected to lead eventually to such a satellite. The schedule for the program is not firm, but NASA testimony to Congress indicates that the goal is four to five years away. This conclusion is reached from the technical specifications that NASA has until now believed are necessary, involving heavy (800 to 3000 pounds), complex payloads with two to three years’ life as an objective. As a more immediate pro- gram, NASA will put a number of 100-foot diameter passive balloon reflectors into orbit during this year. These balloons will be tracked by several organizations, and will provide valuable scientific information. However, such reflectors are not of any real commercial value because [of] large amounts of power per unit bandwidth and immense tracking antennas required to give even the intermittent coverage afforded by low-altitude orbits.

There are several military communication satellite programs now under way. None of these conflict with the commercial program proposed here; the military programs use high power active repeaters in low-altitude orbits in order to avoid any requirements for large antennas at the terminals.

The presently proposed commercial system can be put into operation within one year. This radical improvement in schedule is achieved primarily through the design of a very light (25 pound) satellite repeater, a design based on realistic objectives for satisfactory commercial application. The light payload required with the present concept permits use of an inexpensive solid-propellant booster, the Scout. This results in a program cost of 5 million dollars.

The advantages of such a program would be several fold. Financially, it is believed that the initial development, terminal installations, and launching costs could be recovered in a fraction of the first year’s operation. It is expected that the useful life of a repeater will be about one year, and that the cost of replacing the repeater in orbit will be about 0.5 million dollars.

The suggested communication system is capable of large growth. The first repeater will cover most of the continental United States, all of Europe, all of South America, and much of Africa. An additional repeater would cover Hawaii, Australia, Japan, and other parts of the Orient. In addition to extension of geographic coverage, the existence of the communication link will result in an increase in foreign business which in turn will result in greater use of the facility. Extrapolation of recent trends in overseas messages shows that the present cable capacity between the U.S. and Europe will be exceeded within the next two years. Since the proposed facility is much less expensive than a cable, it is logical to expect this overflow to be handled by the proposed facility.

In addition to its commercial value, the proposed communication satellite should contribute greatly to national prestige and friendly foreign relations.


The proposed communication system consists of a satellite repeater in a synchronous, equatorial orbit operating in conjunction with two or more ground terminals, each of which is linked by land lines or microwave relays to the appropriate domestic communication systems.

The repeater consists of a transistorized UHF receiver and an L-band (2 KMC) transmitter having a power output of 2.5 watts. Since the electrical power is supplied by solar cells, the useful life of the repeater is expected to be limited only by the life of the transmitting tube to about one year. Besides serving as the communication repeater, the receiver-transmitter is also used as a guidance signal repeater, and the receiver additionally acts as a command receiver.

The payload also contains a compressed nitrogen attitude and vernier velocity control system, which provides for proper illumination of the solar cells, correct aiming of the directional antenna, and precise adjustments of the orbit.

The ground terminals consist of a large aperture antenna shared by the 25-KW [kilo- watt] UHF transmitter and the low noise L-band receiver. The antenna reflector will be fixed, and the small departures of the payload from an exactly stationary orbit will be fol- lowed by moving the antenna feed.

The satellite is launched using the NASA Scout, and two additional solid-propellant rockets are used to establish the desired orbit. The launching site will be Jarvis Island, an equatorial island approximately 1300 nautical miles south of Hawaii. The use of this suit- ably located equatorial site results in a large decrease in required propulsion system per- formance and guidance complexity.

Further technical detail is furnished by the following sections of this proposal.  (omitted from the NASA publication)


An estimate of the development cost of the communication system is given in Table 6-1, and an estimate of the cost of the entire program is given in Table 6-2.

The amount of confidence which can be placed in these figures is worth some discussion. The costs of the Scout rocket, attitude guidance, launcher, and ground support equipment were obtained from the Vought Astronautics brochure, “Space Research Vehicle Systems Developed from NASA Scout,” published in August, 1959. The UHF TV transmitter is a production item and its cost is firm. The cost of the ground antenna was estimated by an experienced supplier of such devices. Island construction costs were estimated by an overseas construction company which has had considerable experience with [Atomic Energy Commission] projects in the Marshall Islands.

The development cost estimates were obtained from the individuals who would be responsible for the various items. Although some variation in cost of particular items is to be expected, the chances that the total will remain under the 1.2 million dollar figure seems quite good, because of the strong appeal of the project to creative engineers and the subsequent high degree of enthusiasm with which the job will be performed

Table 6.1 Development Cost

     TWT $0.15M
     Structure   0.15M
     5th and 6th Stages   0.05M
     Environmental Testing   0.25M
          Total $0.70M
     Antenna Design $0.05M
     Transmitter Modifications   0.05M
     Low Noise Receiver Design   0.10M
          Total $0.20M
     Transmitter Design $0.05M
     Receiver Design   0.09M
     Antennas   0.02M
     Computer   0.04M
          Total $0.20M
     Auxiliary Antennas $0.05M
     Computer   0.05M
          Total $0.10M
Total Development Cost $1.20M


Table 6.2 Program Cost

Development Cost
Terminal Cost
     Antenna $0.30M
     Transmitter   0.12M
     Receiver   0.03M
     Building and Land   0.10M
$0.55M     X 2      $1.10M (2)
Jarvis Island Construction
     Construction of Buildings $0.25M
     Construction of Airstrips   0.25M
     Launcher   0.25M
     Ground Support Equipment   0.70M
     Transportation   0.25M
$1.70M     X 2      $3.40M (2)
     Scout with Attitude Guidance $0.361M
     Payload   0.072M
$0.433M   X 3      $1.30M (3)
     Salaries of Field Personnel $0.200M
     Reserve   0.200M
$0.400M      $0.40M
Total Program Cost      $5.00M


It is concluded that it is technically feasible, within the present state of the art of rocket and electronic technology, to establish a commercial 24-hour communication satellite using the Scout rocket vehicle. It is recommended that NASA encourage such a program and recognize it as an important new application of the Scout. This program can be accomplished by the Hughes Aircraft Company within a year at a cost of 5 million dollars.

Commercial Satellite Communication Project; 22 October 1959

Editor’s note:  The Hughes IDC presented below along with the attached NASA commentary can be found in NASA SP-4407, Volume III, 1995.

By 1959, work on communications satellite research and development was going on in several industrial firms besides Bell Laboratories. The Department of Defense had taken the lead in sponsoring research on active repeater satellites, while NASA concentrated its initial efforts on passive reflectors. In particular, the Department of Defense was supporting research on a complex satellite project called Advent, which intended to develop a satellite for use in geosynchronous orbit. An engineering team at Hughes Aircraft in mid-1959, led by Harold Rosen, devised a proposal for a much simpler geosynchronous satellite and asked the company to support its development. This memorandum reports to Hughes vice president for research, A.V. Haeff, the conclusions of an internal task force set up to assess the proposal of Rosen and his team, which also included Donald Williams and Thomas Hudspeth. (The appendices referred to in this memo are not included.) Over the following months, Hughes managers debated whether to provide support for the proposal from company funds or to seek government support for the project. Enough corporate funds were made available to keep the project going, but it was not until NASA contracted with Hughes to develop and demonstrate what became known as Syncom that the project became the foundation for the many geosynchronous satellites to follow.


Hughes Aircraft Company

Interdepartmental Correspondence

 To: A. V. Haeff     cc: See Distribution                        Date: 22 October 1959

Subject:  Commercial Satellite Communication Project;    From: S. G. Lutz    Preliminary Report of Study Task Force

(Task Force working members are: E. D. Felkel,  S. G. Lutz,  D. E. Miller,  H. A. Rosen and J. H. Striebel)

1. It is the unanimous opinion of the Task Force working members that the satellite communication system proposed by Dr. H. A. Rosen is technically feasible, is possible of realization within close to the estimated price and schedule, has great potential economic attractiveness and should not encounter too serious legal or political obstacles.

2. The Task Force has, of necessity, concentrated on technical aspects of the program and has not been able to make an adequate market survey. The phraseology, “great potential economic attractiveness” is justified by the following:

a. A rapidly increasing demand for new long-distance communication facilities is being created by: (1) Population increase, (2) Shrinkage of travel time via commercial jet aircraft, (3) Increasing foreign industrialization and international commerce, (4) Increasing military communication loads, and (5) Forthcoming decrease in HF [high-frequency] communication capability because of the declining sunspot cycle. Rather than being able to open more HF radio circuits to carry the increasing traffic, new circuits (cable, scatter or satellite) will be needed to pick up perhaps a third of the traffic now carried by HF circuits.

b. The Bell System, which formerly depended on radio for intercontinental phone circuits, has been investing heavily and profitably in long submarine cables; four in the past few years. The first trans-Atlantic phone cable provided thirty-six circuits (about 140 kc [kilocycle] bandwidth), cost about $30,000,000.00, and reportedly paid out in its first two years. A second trans- Atlantic cable soon will be placed in service at a reported cost of $40,000,000.00, presumably for a similar number of circuits. Tropospheric scatter radio chains are comparable in cost and are geographically constrained.

c. Comparing the proposed satellite system ($5,000,000.00 for 4500 kc band- width) with submarine cable, it could carry up to thirty times as much traffic at one-sixth the investment!

3. Converting “potential” into “actual” economic attractiveness will depend on acquiring communication traffic, most probably via cooperative agreement with one or more communication common carriers. General Telephone may be the best prospect (certainly a better one than the complacent Bell System) because it is trying to gain stature despite Bell’s long-distance monopoly. The proposed satellite system could bypass Bell landlines in linking General’s east coast and west coast systems, in addition to giving it non-Bell circuits to Europe and other continents. General Telephone also could negotiate more efficiently with the communication services of other countries and even other domestic companies (Western Union, etc.) than [Hughes Aircraft] could; not being a common carrier. This and related market survey problems seemed too sensitive to be explored adequately by the engineers of this task force, even if time and suitable contracts had been available. General Telephone need not be the only potential partner, of course, for even a smaller common carrier might supply enough traffic to get started. As few as six circuits (30 kc out of the available 4500 kc) to Europe should justify a five-million-dollar investment in proportion to submarine telephone cables.

4. . . . (15 October [Interdepartmental Correspondence] from Lutz to Haeff, Jerrems) lists three questions which define the scope of the market survey believed to be desirable. To this list should be added a study of the relative costs and outage times for splicing a broken cable vs replacing a dead satellite repeater. As a preliminary estimate, keeping a launching in readiness on Jarvis Island should be less expensive than keeping a cable ship in readiness and a new satellite could be put up in hours, instead of the weeks required to locate and repair a cable-break.

5. Technical aspects of the proposed program have been evaluated in more detail, and with higher confidence in the conclusions, than was possible with the preceding economic aspects. The crux of the technical attractiveness of this program (and an important economic consideration as well) lies in quick-reaction capability at low cost. By being able to keep the weight of a simple broadband repeater payload below 25 lbs, it can be put in stationary orbit by an inexpensive (one-third million dollars) solid-fuel Scout booster. Everyone else (NASA, RCA, Space Electronics, Signal Corps) has viewed a stationary orbit repeater as a more sophisticated, hence heavier device, with attitude control to use high gain antenna beams on the satellite. More payload weight requires a larger liquid-fueled rocket and severe logistic problems in transporting or making liquid oxygen for an equatorial launch. The alternative of launching from the U.S. and “dog-legging” into an equatorial orbit increases guidance problems and requires Saturn thrusts. Thus, NASA and others consider the stationary orbit communications repeater as a high-cost program for 1965-70. This Task Force has convinced itself of the feasibility of putting 25 lbs, or possibly 30 lbs, into a useful quasi-stationary orbit with a Scout booster, of achieving a 4500 kc bandwidth repeater within this weight and of doing this within a year of the date that full funding is provided.

6. How can Hughes expect to do so much better than others? The answer does not lie in any startling but questionable innovations, inventions or breakthroughs. Rather, the answer lies chiefly in application of the Hughes brand of System Engineering, plus exploiting Hughes competence in low-noise reception and traveling-wave-tube development. The starting point was to assume a quasi-stationary orbit (satellites held within about 5 ̊ angular limits of desired point on the stationary orbit), to be put there by a Scout booster. The limited payload weight to 30 lbs on the basis of Chance Vought performance predictions, or to 25 lbs on derating the predicted velocity by 800 fps. This obviously limits the satellite transmitting power, energized from solar cells, to a watt or so. [3] Transmission at or near 2 kmc (the accepted optimum frequency for space communication) favors high antenna gain and use of traveling-wave-tubes. The nearest to a break- through was the assurance by Dr. J. T. Mandel of the feasibility of developing a 2.5 watt periodic PM focused 2 kmc high efficiency traveling-wave-tube of one pound, including its INDOX VI focusing magnets. The low satellite power is handled at the earth terminals by low noise (cooled maser or parametric) reception and very high antenna gain (58 db). In achieving the latter at reasonable costs, the quasi-stationary position of the satellite avoids the need for full azimuth and elevation control which has been made even 80 ft steerable parabolas so expensive. At similar cost, the beam from a 150 ft truncated parabola can be steered through a +5 ̊ range. Thus, the burden is put on the earth- terminals, where it belongs. The satellite antenna design is a compromise between using an omni-directional antenna for maximum simplicity and using a 17̊ beam for maximum gain. While either of these extremes could be fatal, the compromise of a spin-stabilized doughnut pattern provides 6 to 9 db gain, with simplicity. Finally, with adequate design for a 14 db S/N ratio, the addition of frequency modulation raises the S/N ration to a commercial 32 db.

7. Because of the importance of assessing feasibility of staying within the weight capability of the Scout booster, Ed Felkel was named to the Task Force to analyze the weight of the payload package. His report shows confidence of keeping it safely within weight.

8. Putting the satellite in orbit and keeping it in position entails a sequence of individually practicable operations within today’s state of the art. Cumulatively, however, the multiplicity of stages plus operations of velocity adjustment, de-spinning, re-spinning and incremental orbit adjustment present a currently-indeterminable hazard to the success of any one firing. It is believed that a combination of (a) careful and conservative engineering with step-by-step pre-testing, (b) adequate training on analog simulators, (c) study of any troubles in earlier NASA Scout firings, and (d) adequate determination of the cause of any initial Hughes failure, will result in adequate probability of success within the programmed three tries. Admittedly, there can never be certainty of success in only three attempts. However, a fourth or subsequent firings should not increase the program cost proportionately.

9. As might be expected, the Task Force study has resulted in significant system improvements, by Dr. Rosen as well as by Task Force members and others. For example, the payload configuration has been broadened to improve spin-stability and has been stiffened by a central column. More important, perhaps, has been the swing away from design primarily for television relaying, with additional narrower i-f channels for other communication services, toward the simpler and more flexible and potentially rewarding approach of coordinated use of a broad-band single-channel repeater simultaneously by several earth-terminals. This mode of operation requires that earth-terminals equalize their transmitting powers by monitoring the spectrum from the satellite, rather than depending on AGC of separate i-f channels in the satellite to prevent a too-strong earth- signal from weakening other retransmissions. Also, this mode of operation provides flexibility of bandwidth reapportionment between earth-terminals in accordance with shifting relative traffic loads. In short, this approach overcomes the “two at a time” limitation of most prior proposals and thus approached more closely the eventual many-user “exchange in orbit” concept. Furthermore, it accomplishes this without sacrificing television capability, requiring only that other traffic be limited during a television program and be kept out of the television band.

10. Determination and resolution of possible legal and political problems and governmental restrictions obviously is beyond the scope of this Task Force. A few of the pos- sible problems will be mentioned. The usual difficulties with the Federal Communications Commission can be expected in obtaining a license for a new type radio service for frequencies have not yet been allocated. Similar, or worse, difficulties can be expected with the corresponding regulatory bodies of other nations where earth-terminals are located. Characteristically, the FCC makes no precedent-setting decisions without holding industry-wide hearings and these could be competitively detrimental. Furthermore, the State Department might become involved because of the international nature of this venture. Next, some governmental agency probably has control of Jarvis Island and would insist on approving its use. Finally, NASA probably would have to sanction the commercial sale and use of Scout boosters and could impose other controls on the program, such as requiring provision for removing dead repeaters from orbit, or provision for disabling their elec- tronics in event that the project is abandoned with repeaters still in orbit. As a ray of sun- shine, NASA’s mission is non-military space technology. They have expressed encouragement toward commercial projects which would not require NASA funds. If NASA becomes “sold” on the proposed project, they might provide inestimable assistance in surmounting the other governmental obstacles. One recognizes that exploration by a Hughes representative of the above governmental restrictions could readily “leak” to competitors, or even to the press, and be highly detrimental. This danger can be avoided, it is believed, by retaining a consultant to make this preliminary investigation without disclosing his client or the details of the project.

11. The impact of the proposed program on the military services could be both good and bad. It would be conclusive proof of Hughes’ competence to execute a major space program and in Hughes’ confidence and initiative in undertaking it without governmental funds. Thus, it should put us in better competitive position for managing future governmental space projects. It could have a bad impact, however, in “showing up” the inefficiency of military satellite programs.

12. It is known that Bell,  RCA and probably other large companies recognize the potential attractions of satellite communication and probably have program plans. It is reasonable to assume that Bell would plan to invest several times the cost of the trans-Atlantic cable in a big stationary orbit project, timed to the availability of big boosters, five or ten years hence. Pressure for additional international circuits may lead them to re-examine the feasibility of moving faster by using a smaller booster and lighter payload, much as we propose. Certainly they could be expected to do this if they learned that their chief competitor, General Telephone, planned such a program in cooperation with Hughes. Most of the prestige value and a portion of the economic value would be sacrificed if our communication satellite were not the first. This indicates the need for a quick decision and a fast program under tight security.


 I. If another company gets into orbit first, much of the publicity and prestige value will be lost and we would have to compete for traffic. Furthermore, this must be a low-cost program and delays increase costs. Consequently, the program should be planned to start development now. The expensive commitments (for rockets, ground installations, etc.) can be deferred for a few months without delaying the launching date.

II. Fund the traveling-wave-tube development separately as a commercial product. A one-pound tube of this capability should find application in Signal Corps portable microwave relay repeaters, possibly in field television transmitters, as well as in other programs. A quarter-million for its development seems a normally good product development risk. This tube is the heart of the proposed satellite electronic system and will be its longest lead-time component.

III. Fund the remainder of the payload development and earth-terminal (antenna and low-noise receiver), in an amount of about $850,000.00.  Also, take an option three Scout boosters, plus necessary real estate,  etc. If this is too large a commitment in advance of completion of the comprehensive market survey and negotiations with potential customers, fund a sufficient fraction to carry the development program this long. Delaying the start of development would delay completion of the program correspondingly.

IV. Explore with General Telephone Company,  at top management level, their interest in a non-Bell long-distance and overseas capability and their willingness to cooperate as the common carrier in the proposed program. Avoid disclosing details which might permit General’s electronic subsidiary, Sylvania, to attempt to replace us. Reach a working agreement which will permit prompt working-level discussions of General’s cooperation in the program. If negotiations with General fail,  try the next best company.

V. A task force, or project team, consisting of key personnel loaned as required from several organizations—Communications Division, Research Laboratories, Systems Development Laboratories—should be set up to carry out the program.

Success: The Surveyor Missions

The Surveyor I spacecraft was launched from the Kennedy Space Center at 14:41 GMT on May 30, 1966 by the Atlas Centaur (AC-10) using the direct ascent single burn mode for

Launch of Surveyor I, May 30, 1966

Centaur. It soft landed on the lunar surface at 6:17 GMT on June 2. Some thought it was miraculous that Surveyor succeeded on its first attempt. Bob Roderick, the Hughes project manager, said when asked prior to launch what were the chances of success, “A thousand to one.” And the mission was carried on live national television. When the first picture of the lunar surface and one of the footpads appeared some minutes after touchdown it was there on your living room TV. The same picture lingered for such a long time that jokes were made that the operations crew was so surprised at the successful landing that they had no further procedures available.

Needless to say this mission was a huge success. Over 11,000 pictures were returned from the moon and it was definitely proved that objects landing on the moon would not sink into many feet of lunar dust as some scientists had predicted. The spacecraft survived the lunar night and came alive with the rising sun on July 6 and returned even more pictures.

The Shadow of Surveyor I At the End of the First Lunar Day

It came to light after the soft landing that an American flag had been carried to the moon by Surveyor I. It had been purchased by Shel Shallon, Hughes Surveyor project office staff, from a SavOn drug store in Los Angeles for 23 cents.  After carefully cleaning the flag, Shel had a technician in Florida place it in a structural member of the spacecraft. This caused some concerns with NASA and JPL officials, but since the mission was successful, this was not a major issue.

In an apt follow up to the successful Surveyor I mission, Pat Hyland, Hughes vice president, placed a telephone call to Bob Seamans, NASA Deputy Administrator, and asked him, “Have you got any more programs that you want us to screw up?”

The Surveyor 2 spacecraft was launched from the Kennedy Space Center at 12:32 GMT on September 20, 1966 by the Atlas Centaur (AC-7) using the direct ascent single burn mode for Centaur. The mission was terminated when as a result of a vernier engine failure during the midcourse maneuver the spacecraft tumbled out of control.

The Surveyor III spacecraft was launched on at 7:05 GMT on April 17, 1967 by the Atlas Centaur (AC-12) using the parking orbit mode for the first time in an operational mission. This mode requires a Centaur restart in orbit. A soft landing was achieved at 00:04 GMT on April 20, 1967. The vernier engines did not shut off at touchdown and continued in operation until shut down by ground command. Subsequently the spacecraft lifted off twice before finally coming to rest. The landing occurred on a 12.5 degree slope inside a 200 meter crater. An additional payload of a soil mechanics surface sampler that allowed digging, picking and handling of lunar soil was included. The spacecraft operated through the first lunar day, experiencing a total eclipse of the sun by the earth and returning 6300 pictures.

Surveyor 4 was launched from the Kennedy Space Center at 11:53 GMT on July 14, 1967 by the Atlas Centaur (AC-11) using the Centaur direct ascent single burn mode. Contact was lost with the spacecraft just prior to burn out of the solid rocket motor and could not be recovered.

Surveyor V was launched at 07:57 GMT on September 8, 1967 by the Atlas-Centaur (AC-13) using the parking orbit injection mode that required a Centaur main engine restart after a 7-minute coast period. A significant problem developed during the transit phase when it was discovered that the helium tank that provides pressurization for the vernier propulsion system had developed a leak. A significant effort by the mission operations crew developed a workaround plan that resolved the problem—see Surveyor V Odyssey. As a result of this effort the spacecraft soft-landed on the lunar surface at 00:46 GMT on 9/11/67 at the planned landing site. About two days after landing the vernier engines were fired briefly (0.55 seconds) to observe erosion effects on the lunar surface at the request of the Apollo program office. An alpha scattering instrument provided data for the chemical analysis of the lunar surface material. The spacecraft returned 19000 pictures. During the second lunar day the spacecraft returned another 1000 pictures. Surveyor did not respond to any commands on the third lunar day but was reawakened on the fourth lunar day setting a record by surviving three lunar nights.

Surveyor VI was launched at 07:39 GMT on November 7,1967 by the Atlas Centaur (AC-14) using the parking orbit ascent mode. Touchdown occurred at 01:01 GMT on November 10, 1967. The highlight of this mission was the performance of a lunar hop. The vernier rocket engines were restarted and fired for 2.5 seconds. This lifted the spacecraft 12 feet off the surface and moved it laterally 8 feet. The Surveyor VI television camera provided the best quality pictures and returned over 30000 pictures. The alpha scattering instrument was operated extensively and provided chemical analysis of the lunar surface material. The spacecraft survived the lunar night, but could not sustain any further operations.

Surveyor VII was launched at 6:30 GMT on January 7, 1968 by the Atlas Centaur (AC-15) using the parking orbit ascent mode. Touchdown occurred at 1:05 GMT on January 10, 1968. The prior Surveyor landing sites were all in the area being considered for Apollo mission landings near the lunar equator. The landing site selected for Surveyor VII, shown below, was in the lunar highlands at 41 degrees south latitude and was of greater interest to the scientific community.Both a alpha scattering instrument and a soil mechanics surface sampler were carried on this mission. The surface sampler was used to overcome an alpha scattering deployment problem and to move the instrument on the lunar surface. The spacecraft returned 21000 pictures and survived the first lunar night and continued operations until February 20.

Apollo 12 with astronauts Pete Conrad and Alan Bean landed at the Surveyor 3 landing site and recovered pieces of that spacecraft on November 19-20, 1969.

Pete Conrad With Surveyor III

The Surveyor V Odyssey

The Surveyor V Crew: Jim Cloud, Mal Meredith, John Ribarich, Neal Hertzmann, Ed Ellion, and Len Davids

Editors Note:  This description of the recovery of Surveyor V originally appeared in a special edition of the Hughes News on September 15, 1967.  It is believed that Jim Cloud provided the technical details herein.

A telephone call from a JPL man located at El Segundo, buckets collecting simulated spacecraft fuel at a remote spot in Placerita Canyon, a word that probably no more than one in a thousand had heard, and a tremendous effort sparked by HAC’s Jim Cloud all figured heavily in Surveyor V’s successful soft landing on the moon Sunday evening.

Mr. Cloud, husky, brown-haired 15-year Hughesite who has been with the Surveyor Program since its inception and is the assistant program manager for Engineering/ Manufacturing, was credited by NASA and JPL officials with leading the sterling effort that saved the mission after a problem in the high pressure regulator made success appear only remotely possible.

And while the rest of the world waited breathlessly right up to the touchdown at 5:46:45 pm (PDT) Sunday for the moment of ultimate success, Mr. Cloud was convinced as early as Friday evening that Surveyor V was a good bird and would make it all the way.

 No Guesswork

 He was specific in his interpretation of why Surveyor V succeeded as he recounted with uncanny detail the hair-raising 48 hours between the time the trouble developed and touchdown.

“People and the flexibility of the spacecraft, “ he said, “but primarily people. We had a great team and nothing asked wasn’t done. Everyone worked long, hard hours to get the job done. The whole effort was just tremendous.”

He didn’t say it (NASA and JPL officials said it for him), but he was there the entire time leading the effort, making and assessing critical calculations all the way, and coming up with the right decisions at the right time.

It all began just before the scheduled midcourse correction, a mere 1 degree change in trajectory to put the spacecraft right on target in the moon’s Sea of Tranquility. The Atlas Centaur booster had been extremely accurate, the best yet in a Surveyor launch. But that 1 degree change was required to put Surveyor at the exact spot NASA wanted to explore as a potential landing site for the Apollo astronauts.

 Involves Verniers

 Midcourse correction and the final phases of terminal descent involve three vernier engines aboard the Surveyor spacecraft. The vernier system includes three thrust chambers and a propellant feed system composed of three fuel tanks, three oxidizer tanks, and high pressure helium tanks, propellant lines, and valves for arming, operating, and deactivating the system.

Each vernier engine has a pair of fuel and oxidizer tanks. The tanks contain Teflon expulsion bladders to permit complete and positive expulsion of their contents. These bladders are deflated by injecting pressurized helium into the tanks, forcing fuel and oxidizer into the feed lines. The fuel and oxidizer ignite immediately when they mix in the thrust chambers.

The midcourse correction was executed successfully with a 14-second vernier engine burn. Then, propulsion specialists reported a possible anomaly in the helium pressure.

“Within a couple of minutes we were assessing data and in 5 minutes confirmed that we were losing pressure through the high pressure regulator,” Mr. Cloud said.

 Particle or Damage?

Ed Ellion, manager of the Propulsion Department in Space Systems Division, and Bob Breshears, head of the Propulsion System Analysis group for Surveyor (and also cited by NASA and JPL of outstanding work), were called in and hypothesized two failure modes.

The first was that a particle, barely visible to the naked eye, had become stuck in the valve seat. The second, the valve seat may have been damaged during final testing on earth.

At any rate, the propellant tank pressure increased to the point that it opened the relief valve and vented helium into space.

They quickly calculated the burning time required to establish a pressure differential to keep the valve open long enough to dislodge the particle, if that were the case.

Flight path and trajectory people preferred to turn the spacecraft around 180 degrees before firing the engines to maintain the trajectory, but with the pressure dropping so rapidly it was decided to fire the engines and thrust the spacecraft off the trajectory with a sun line maneuver, or toward the sun, one of the standard reference points (along with the star Canopus).

 Attack Begins

That first non-standard burn was for 10.05 seconds. John Ribarich did the maneuver analysis, as he did for all the maneuvers up to the terminal descent.

It immediately became clear that the pressure decay had not diminished and a second non-standard vernier engine burn was ordered, this time away from the sun to compensate for the sun line maneuver. The firing went 23 seconds.

The problem persisted. Thirty-five of the 180 pounds of fuel on board had been used, the standard allowance for midcourse correction. NASA, JPL, and HAC officials huddled to discuss the problem, the mission, and possible alternatives, including the much publicized high earth orbit.

Mal Meredith, manager of the Guidance and Trajectory Department in Space Systems Division, who worked with Mr. Cloud on the trajectory and terminal analysis, joined with JPL’s Bill O’Neil to calculate the possible earth orbit. Mr. Breshears was convinced that the spacecraft could be put into earth orbit at any time until the helium pressure registered 1900 psi.

Then came the call from the JPL man assigned to Surveyor work at El Segundo.  Editor’s note:  The consensus is that Don Pedretti, who later became a Hughes employee, placed this telephone call from his assigned location at KSC in Florida.

Don Pedretti asked if the ullage factor had been taken into account.

Ullage, the word so little known, is the amount of space a container lacks of being full. If the ullage in the fuel tanks and high pressure helium tank could be filled with trapped gas resulting from engine firings, that gas would serve as a pressure against the fuel and force it into the feed lines, just as the escaping helium would do.

At this time, Mr. Breshears determined that the ullage pressure would be great enough at any time almost up to the moment of impact to allow firing of the main retro and perhaps a little more. If so a landing might be possible.

“This was the turning point,” declared Mr. Cloud. “Now the odds were down to about a 1000 to 1 for a successful landing even though the minimum fuel requirements permitted only a few hundred feet of error at touchdown.

 Battle Gets Hot

 The battle to land on the moon was now joined in earnest.

Late Friday, Merle Guenther headed a JPL crew that began testing actual engine flow rates as a function of feed pressure at Edwards AFB. This data was used to confirm prior calculations of engine capability to control the vernier descent with a decreasing pressure system. Later, they took the engines to the Hughes test site in Placerita Canyon to check the ullage theory on the S-6 test vehicle, outfitted with a fuel system.

Dr. Ellion, Phil Donatelli, head of Surveyor Vernier Propulsion Section; Frank Danis, and several other Hughesites, working in conjunction with JPL counterparts at Placerita, filled the propellant tanks on 820 psi to simulate the predicted ullage pressure on the vernier engine tanks on Surveyor V at terminal descent, using alcohol and Freon.

Buckets were placed under each of the thrust chambers and the engines were fired. When the engines stopped firing at 500 ps1 (below that figure the engines won’t operate), the alcohol-freon expelled into the buckets weighed 68 pounds.

That was Sunday morning…and the odds for success improved vastly, between 1 in 4 and 1 in 10.

Between the completion of the tests at Pacerita and the actual terminal descent phase, three thrusting maneuvers, all analyzed by Mr. Ribarich, were executed to lighten the vehicle, to attempt to trap more ullage gas, and to pinpoint the spacecraft on the landing site. The final 5-second tweak burned off 4.3 pounds of fuel and put the spacecraft back on the original trajectory despite the zigzag flight from earth and left a helium-ullage pressure of about 850 psi, sufficient for the landing.

Also late Saturday, the men involved in determining the non-standard terminal descent began the horrendous task of dovetailing seemingly infinite numbers of calculations in order to put Surveyor V in the right place, at the right time, at the right speed.

Men worked furiously computing, calculating, checking, performing in minutes and hours functions that normally take days and weeks.

 But Restrictions Tough

 All they had to do was come up with an entirely new terminal descent sequence to override the pre-programmed sequence data already onboard the spacecraft. Only now, the restrictions were twice as severe as for a normal landing.

All functions in the terminal descent phase normally accomplished in a three minute period now had to be performed in about half the time.

New and precise times for igniting the vernier engines and main retro rocket, commanding the jettison of the main retro rocket, as well as turning the thrusters to high power thrusting, had to be determined.

Jettisoning of the main retro rocket, normally accomplished at about 35,000 feet, would have to be done at slightly more than 4000 feet, with the possibility that it would remain trapped in the descending spacecraft. And additional steering time was desired so that the radar altimeter doppler velocity sensor would be effective.

Time, on earth and at the moon, was a critical factor.

Key figure in solving the timing problem was Neal Hertzmann, manager of Flight Control Subsystems. In a simulation study, conducted Saturday night, he determined that it would be impossible to initiate steering before main retro burnout as proposed. The simulation showed that with the acceleration loop saturated steering would not be effective and a significant limit cycle was possible.

Based on this information, for main retro jettison and vernier engine high power thrusting, plus further data on retro engine “tail-off” supplied by Larry Spicer of HAC and Rich Haserot of JPL, HAC’s Len Davids came up with a new terminal descent analysis.

Mr. Davids, of the Guidance and Trajectory Department, manually calculated the proposed descent on plotting paper, put the data into a 7094 computer at JPL, used the time-shared GE 265 computer in Bldg. 105 at the Airport Site via tie line, and modified the information on the spot in Space Flight Operations Facility at JPL. (In Bldg. 105, Chief Switchboard Operator Elsie Grob spent virtually all of Saturday and Sunday handling tie lines which had problems of their own.)

The new non-standard terminal descent sequence was confirmed late Saturday in a closed-loop simulation designed by Jan Sikola at Space Flight Operations Facility and conducted on Surveyor SC-6 at Cape Kennedy being prepared for launch.

All data that would override the on-board data was put on the final tape a couple of hours before the scheduled landing.

To pre-plan such a landing with its extensive maneuvers would normally require 4 to 6 weeks. The 20 to 30 men who lived with the mission accomplished the virtually impossible in 40 hours.

The name Surveyor V will be long remembered, but it never would have made the headlines without names like Neal Hertzmann, Arnold Neil, Len Davids, Mal Meredith, Ed Ellion, John Ribarich, Bob Breshears, Frank Danis, Larry Spicer, Rich Haserot, Merle Guenther. Paul Sterba, who computed the new center of gravity on the vehicle after the loss of helium to see that the capability for attitude control during main retro burn hadn’t been upset.

 Others Named

 Also Dick Dibos and Frank Rickman, who determined the final roll angle for optimum operation of the radar altimeter doppler velocity sensor at low velocities; George Kerster, who contributed to the terminal sequence timing and retro tailoff work; Jack Stockey and Jeff Leising of JPL who determined that retro would have to follow burnout by more than 5 seconds or it might bump the spacecraft.

Without Ed Pfund, HAC’s director of Spacecraft Performance Analysis Command and Bud Wrather, head of Mission Control, and Ray Cress at Goldstone, who performed coolly throughout the mission. Without Ed Hawthorne, spacecraft manager, who put together a bird that through its flexibility met every challenge.

And certainly without Jim Cloud, directing, calculating, making the critical recommendations to the JPL project office for the final decisions.

Editor’s note:  Several months later Hughes published a report with the technical details of the Surveyor V mission.