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On Mars: Exploration of the Red Planet. 1958-1978

[192] Money problems would always haunt the Viking project. The scarcity of dollars especially affected the development of the lander and its science payload and repeatedly tried people's patience and equanimity. Early in 1973, Joseph R. Goudy, the Langley Viking Project Office resident engineer at JPL, commented on budget cuts that led to the dismissal of about 200 employees at the California laboratory on rather short notice:
These cutbacks have created a different atmosphere and environment, resulting in a change in attitude. Six months ago, when the [Viking Project Office] came in with a new requirement or direction that required additional or premature effort, it was generally accepted with the attitude. "We don't think it's necessary but it's their money; if they want it, we'll do it." Now, with the Orbiter having to take rather severe cuts, this is no longer considered "their" money and the attitude has become much more critical. if not down-right hostile. 66
Henry Norris, looking for ways to keep his orbiter personnel from reacting too negatively to the repeated budget cuts, tried to convince them-and for the most part he succeeded-that the budget was just one of the many realities that a good engineer or manager had to live with and work around as he tried to do his job.
The tasks assigned to the orbiter teams were laid before them in a five-year schedule, which ended with a pair of mid-summer 1975 launches. The master plan was presented for the first time at the Viking Project Management Council meeting in February 1970, and it reflected the changes brought by the stretchout.
The pace of the work at JPL assumed a rhythm familiar to the people who had worked on other NASA projects. The determining factors, "drivers"....

Table 33 [193]

Viking Orbiter Schedules


Proposed before

Proposed after


1 Jan. 1970

1 Jan. 1970


Preliminary design review

May 1970

Jan. 1972

19-20 0ct. 1971

Critical design review

June 1971

Jan. 1973

9-lO July 1973

Start proof-test spacecraft test

Aug. 1972

March 1974

Jan. 1974

Qualification test completed

Nov. 1972

July 1974

Jan. 1975

Shipment of first flight hardware to KSC

Feb. 1973

Dec. 1974

Feb. 1975


July 1973

July 1975

20 Aug. 1975

9 Sept. 1975

SOURCE: Information on the 1970 master plan was awaken from Henry Norris, "Viking Orbiter Project Staff Meeting- Minutes of January 13 and 14, 1970," memo, 19 Jan. 1970.

....in NASA parlance, for the designers and engineers were master schedules that determined when major hardware components had to be completed so the launch dates could be met. But the realities of designing and building the spacecraft did not always conform to calendar milestones, and the variance led to frequent revisions of the schedules. At every step along the way, the work was formally documented in a large number of Viking project documents. By cross-checking and coordinating these documents, the project manager at Langley could be assured that the orbiter, lander, science payloads, launch vehicles, ground support equipment, flight control facilities, and the tracking system would all function as required when the hardware was brought together and assembled for the launch and flight to Mars. This system of mass documentation, formal reviews, telecons, and informal conversations worked because the people associated with the effort believed in delegated management. Jim Martin's centralized responsibility and authority for Viking was a key factor to the project's success, but equally important was the esprit de corps among the Viking teams at the working level. 67
The troops at JPL functioned within divisions responsible for specific engineering activities or disciplines. Norris and his orbiter staff allocated funds, prepared plans and schedules, assigned tasks, and received progress reports, but the divisions carried out the actual design and development of the spacecraft and experiment hardware, as well as prepared and operated such facilities as the Deep Space Network and the Space Flight Operations [194] Facility. Each division chief and his subordinates not only supervised their personnel but also selected the engineers who represented their divisions on the orbiter team.* 68
The structure of management at JPL did not fit Jim Martin's management scheme. The people at Langley had always worked through a more centralized organization, in which everyone was directly responsible to the project director, and the Viking Project Office was uneasy with the JPL system. Martin knew that the organizational structure of the lab would not likely be changed just for this mission, so he went to Pasadena in the early spring of 1970 to observe firsthand how JPL worked. Specifically, he wanted to know: How had JPL dealt with hardware problems in the past? How did it plan to manage the Viking orbiter in the future? How would it control the flight phase of a mission? 69
Henry Norris believed that the time Martin spent with division managers and Viking representatives at JPL led him to understand more clearly the lab's approach to project management. Martin was still "not entirely comfortable" with the organization, Norris reported, but at least the project director had been exposed to it and the men who filled the ranks. Likewise, the people at JPL began to appreciate the sources of Martin's concerns and continued to work with the project office to improve and strengthen JPL management control over the teams in Pasadena. 70
Although they had adopted different approaches, the personnel at Langley and JPL were working toward the same goal. Once the baseline orbiter configuration had been established in February 1969, the next major orbiter goal was the preliminary design review (PDR). This formal review, held on 19-20 October 1971, came at the end of the conceptual phase for the design of the orbiter systems; the specialists were now ready to work on the detailed design of the hardware. Once the basic soundness of all aspects of the orbiter was approved, the teams would head for the next important milestone, the critical design review (CDR). Getting to the PDR had been a major accomplishment. made difficult by the repeated problems with the budget; but the teams at JPL had completed their design work and coordinated their efforts, attending weekly meetings and frequently using the telephone along the way. In fact. more than 60 meetings were held that directly impinged upon the design of the orbiter.
The preliminary design review gave all interested parties a look at the orbiter as JPL planned to build it. Once the conceptual design was complete, work on the design of breadboards, or first working test models, of the basic orbiter subsystems would begin. These designs would be evaluated at subsystem PDRs an once approved, work on e breadboards would [195] proceed, with their suitability for conversion into flight hardware being confirmed during a series of subsystem critical design reviews. A general A general CDR for the entire Viking orbiter system would certify the readiness of the orbiter staff to go to the next step-building the flight-ready orbiters.
By October 1971, the orbiter had assumed the basic configuration it would have when launched in 1975. The spacecraft had grown considerably larger than its Mariner Mars 71 predecessor. Most noticeable visually were the larger solar panels and the larger high-gain antenna. But all the internal subsystems were taking on a Viking identity of their own as well. The Mariner inheritance was still there, but instead of directly transferring subsystems from one craft to another, the engineers were borrowing from Mariner experience and know-how. Still, it was this transfer of technological knowledge from Mariner Mars 71 and Mariner Venus 73 that permitted the Viking orbiter personnel to get the craft ready to fly on time with a minimum of problems and money crises.
Jack Van Ness, deputy Viking project manager, recorded in his "Viking Weekly Highlights Report" that the orbiter system preliminary design review was well organized and informative. Only 22 action items remained for solution. "This relatively small number is somewhat indicative of the clarity and thoroughness of the presentations." At the conclusion of the review, the Viking Advisory Review Panel and the Orbiter System Manager's Advisory Panel provided a favorable overall evaluation of the orbiter status. None of the evaluations turned up any critical problems that would give Martin's Viking Project Office cause for concern. 71
With the PDR behind them, Norris's people began to prepare the detailed designs of the 21 orbiter subsystems. Soliciting requests for proposals from industrial contractors, selecting companies to build the subsystems, and negotiating contracts occupied the months from October 1971 to July 1972. One contract was not let until July 1973. Meanwhile, the various divisions at JPL bad begun to work on the subsystems that would be built at the laboratory. Preliminary design reviews for these subsystems began in January 1972 and lasted until late November.
Close on the heels of the PDRs came the subsystem critical design reviews, which spanned January to July 1973. When the subsystem CDRs were completed, a general CDR at JPL 9-10 July 1973 evaluated the entire orbiter system as it had evolved to date. The CDR panel, the Viking Advisory Panel, and the Orbiter System Manager's Advisory Panel all expressed their confidence in JPL's performance and the quality of the teams' work. 72 The technical problems being encountered by the orbiter were the routine kind that appeared during the course of most spacecraft projects-recurring difficulties with poor-quality integrated circuits and an unhappy experience when an early production propulsion tank ruptured because of a metallurgical failure.
During the summer of 1973, only two subsystems caused genuine concern. The infrared thermal mapping (IRTM) subsystem was behind [196] schedule, but by mid-July the Santa Barbara Research Center had the trouble under control, and the subsystem CDR was held that month. The data-storage-subsystem tape recorder's failure to operate at a satisfactory speed put it on the Viking Project Office's "Top Ten Problems" list. In October the "54L" integrated circuits were also added to the list. Overall, however, the orbiter was shaping up as a well-behaved spacecraft, and everyone was pleased. Concern over the orbiter's financial problems was constant, but the project management was confident that Henry Norris's teams were on schedule and doing well. By drawing on Mariner heritage, they had the Viking orbiter under control. 73
In mid-1973, the orbiter hardware entered the test phase. The first test, called the modal test, was conducted with the orbiter development test model, to determine if the mathematical model used for the engineering load analysis was correct. The modal test ran from late May until the end of July. A week later, General Electric delivered the first computer command subsystem. In late August, the propulsion-system engineering test model was test-fired at the NASA Edwards Test Station in California, while at JPL the flight-data-subsystem breadboard was checked out with other pieces of hardware that were to be linked to it, such as the visual imaging subsystem, the IRTM, and the atmospheric water detector. During the first and second week of September, other tests were run to determine the effect of shock on various orbiter instruments. Joseph Goudy reported to Martin on the 14th that the results from the pyrotechnic shock tests were much better than they had anticipated: "None of the subsystems that were on board for the tests appeared to have suffered any adverse effectsŠ." The sensitive instruments would not be harmed when the spacecraft was explosively separated from the Centaur launch vehicle stage and the lander was explosively separated from the orbiter. 74 In mid-December 1973, JPL completed the vibration stack test of the orbiter and lander development test models. Since this was the first time that orbiter and lander hardware had been mated and tested together, everyone in Pasadena was particularly satisfied when no important questions were raised by the examinations. 75
With the new year upon them, the orbiter team focused its attention on final assembly of the proof-test orbiter and tests of this first flight-style hardware. These qualification tests would determine the spaceflight worthiness of the orbiter system designs as they had been rendered into hardware. The assembly process took three months as each of the subsystems was checked out and assembled onto the orbiter bus. During April and May, the engineers at JPL conducted the system readiness test, verifying the functioning of all orbiter components. The successful examination of the orbiter hardware prompted Goody to report to the Viking management at Langley that they were on schedule and that the assembly of the proof-test orbiter had served as a "pathfinder" for the fabrication of the flight orbiters. 76 In the process of building this first craft, officially designated Viking orbiter 1 (VO-l), the spacecraft assembly personnel members at JPL learned some....

Table 34 [whole page 197]

Growth in Capacity of Data Storage Subsystems

Mariner 64

Mariner 69

Mariner 71

Viking 75

Number of tape






Number of tracks




8 x 2

Recording rate


16 200 bits per sec

132 000 bits per sec

301 172 bits per sec, tracks1 through 7; 4 and 16 kilobits per sec, track 8

Playback rate

81/3 bits per sec

270 bits per sec

1, 2, 4, 8, or 16 kilobits

1, 2, 4, 8, or 16 kilobits

Storage capacity

5.4 million bits

23 million bits

180 million bits

640 million bits x 2

Length of tape

100 meters

111 meters

168 meters

384 meters x 2



19 kg

11 kg

7.7 kg x 2



Lockheed Electronics Co. Inc., Plainfield, N.J.

Lockheed Electronics

Lockheed Electronics

NOTE: The data subsystems (reel-to-reel tape recorders) used on the Mariner and Viking spacecraft permitted recording scientific data and sobsequently playing it back through the communications subsystem for transmission to Earth. As the number of experiments increased and the amount of data to be stored and played back grew, successive data storage systems became more complex. Each new tape recorder had greater capacity, posing new technological challenges. In Viking, each data subsystem rape recorder weighed 3.3 kg less than the Mariner 71 data subsystem recorder, while having 3.6 times the information storage capacity.That accomplishment took time and caused some real headaches for the Viking managers, but the completed recorders worked very successfully during the missions.

[198]....important lessons that would help them build Viking orbiter 2 and 3, the orbiters that would fly to Mars. One problem they encountered was the lack of sufficient work stands, particularly during the installation of the thermal insulating blanket. More stands were ordered, to avoid any bottleneck during the assembly of the flight articles. The proof-test orbiter was moved on 8 May from the Spacecraft Assembly Facility to the Environmental Laboratory, where it would go through the rigors of vibration, electromagnetic interference, pyrotechnic, thermal vacuum, and compatibility tests during the summer of 1974. At the same time, engineers would begin assembling and testing VO-2 and VO-3. 77
On schedule with satisfactory results, the VO-1 tests were completed in late August. As the JPL team turned its attention to readying VO-3 for early examination, however, unexpected budget problems brought a change in plans. 78 On 27 September, the orbiter staff was forced to order all testing of the third orbiter to cease. The second test team was disbanded; no money was available for testing. VO-3 was put into storage, and the proof-test orbiter (VO-1) was redesignated a flight unit. VO-1 and VO-2 would be the....

The thermal-control model of the Viking orbiter mated to the lander thermal-effects simulator was used in August 1973 to verify the effects solar radiation would have on the spacecraft. The science platform with imaging system and other instruments is attached under the orbiter.

[199] Building the Viking Orbiter at Jet Propulsion Laboratory in 1974. Men working inside the chassis, right, fabricate the orbiter bus structure. Below right, they attach the propulsion module to the propellant tanks. Below, solar panels are in place on the nearly completed orbiter.






[200]....spacecraft sent to Mars. To ensure the acceptability of the proof-test hardware for flight, a series of meetings were held during the next several weeks. 79 But an orbiter design qualification review scheduled for early October 1974 lost much of its significance, since the change in plans had thrown off JPL's timing. As one participant observed, it was hard for a review panel "to determine if the Orbiter met all of its requirements in spite of all the testing that has been done." 80
After several more months of work, orbiter VO-1 was verified for flight on 9 January 1975, and the VO-2 tests were completed on the 31st. The orbiters were shipped to the Kennedy Space Center in February, where a series of preflight checks would be made through the spring and summer. 81 The Viking orbiter, remarkably close to early weight predictions (see table 35), was a very carefully tested piece of equipment. For the teams at JPL, the design, development, fabrication, and assembly had, for the most part, gone according to plan, schedule, and budget.

Table 35

Viking Orbiter Specifications, 1969-1975

Orbiter Element

Baseline Orbiter

PDR Orbiter

Flight Orbiter

Feb. 1969

Oct. 1971

Feb. 1975

Bus dimensions:

- Long sides



139.7 cm

- Short sides



50.8 cm

- Height

45.7 cm

45.7 cm

45.7 cm

Distance from launch vehicle attachment points to lander attachment points


3.29 m

3.29 m

Distance across extended solar panels, tip to tip


9.75 m

9.75 m

Weight with fuel

2298.6 kg

2304.3 kg

2324.7 kg

Weight of fuel

1862 kg

1404.8 kg

1422.9 kg

Weight of science instruments

57.6 kg

65.4 kg

65.2 kg

- Visual imaging system

21.8 kg

42.05 kg

40.05 kg

- Infrared thermal mapper

13.6 kg

7.48 kg

9.30 kg

- Mars atmospheric water detector


15.90 kg

15.90 kg

SOURCE: JPL "Viking Project Orbiter System, Visual Presentation, February 13, 14, 1969''[Feb.1969]; JPL "Viking 73 Project Orbiter System PDR, October 19-20,1971, Presentation Material ' [Oct.1971]; and Martin Marietta Aerospace, Public Relations Dept., The Viking Mission to Mars (Denver, 1975). pp.III-25,III-27,III-32,III-33.

[201] Configuration of the mated Viking orbiter and capsule in cruise mode.

[201] Carl D. Newby, supervisor of the Spacecraft Development/Mechanical Support Group, oversaw the assembly of the orbiters. It was the biggest spacecraft Newby and his team had built, and because it was so big it was an easy craft on which to work-they had room to move around during the assembly process. Newby pointed out that it requires a special personality to work on space hardware and a special dedication. Fabricators come to view the spacecraft as part of their lives, to care about it. Working in a closed environment, they have to learn to live with one another, as well. Spacecraft builders must be adaptable, very careful, and thoughtful. One false move, one thoughtless motion can destroy an assembly or component worth thousands of dollars or months of time. Damage to a spacecraft usually also requires requalification of the injured components or perhaps requalification of the entire craft. Workers on the Viking orbiters-many had worked on Ranger most had worked on the Mariners-were very fond of their spacecraft.As Newby repeatedly reminded the specialists at JPL, the orbiter was a "good spacecraft to work on, it was on time and on budget." 82 Building the Viking landers, however, was a completely different story.

* Divisions and their representatives assisting the Viking orbiter staff at JPL, spring 1970: Quality Assurance and Reliability, G.E. Nichols; Project Engineering, V.R. Galleher; Data Systems, G.F. Squibb; Space Science, M.T. Goldfine; Telecommunications, J.R. Kolden; Guidance and Control, A.E. Cherniack; Engineering Mechanics, W.J. Carley; Astrionics, J.D. Acord; Environmental Sciences Simulation, N.R. Morgan; Propulsion, W.J. Schatz; Mission Analysis, P.K. Eckman; and Technical Information and Documentation, S.B. Hench.