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On Mars: Exploration of the Red Planet. 1958-1978
 
 
THE MISSION MODE DECISION
 
 
 
[148] An intensive series of meetings was held at Langley in late October and early November 1968. Part of the mission definition process, the two-week session was under the leadership of Jim Martin. Besides Langley's Titan Mars team, John Naugle. Ed Cortright, William Pickering, Don Hearth, and other senior staff members from headquarters, Langley, and JPL were there. The first week was set aside for contractors. as Hughes. McDonnell. General Electric, Boeing. the Martin Company, and JPL presented their reports and mission recommendations. 57 During the second week's internal agency deliberations, the Mars 73 team summarized the contractor reports and outlined the possible options:
 
Launch Vehicle (Titan III-C or Titan Centaur)
Support Module (Orbiter or Flyby)
Entry Mode (Direct or Orbital)
Lander (Hard or Soft, 3-Day Life or Extended Life)
Launch Mode if orbiter selected (combined or Separate) 58
 
Viewed dispassionately, it was generally agreed. all the alternatives were technically feasible. but the real question centered on what NASA could afford and realistically recommend to Congress.
 
Jim Martin's team presented two mission made alternatives to the NASA managers-(1) a Titan IIIC-powered direct-entry hard-lander with a flyby module, or (2) a Titan-Centaur-boosted orbital-release soft-lander..... 
 
 

Table 24 [149]

20 Alternative Mission Modes Examined for Viking 73

Launch Vehicle

Delivery Mode

Lander

Lifetime

Support Module

Titan IIIC

Out-of-Orbit

Soft

Extended

Autonomous

Titan IIIC

Direct

Hard

3-day

Flyby

Titan IIIC

Direct

Soft

3-day

Flyby

Titan IIIC

Direct

Soft

Extended

Autonomous

Titan IIIC

Direct

Hard

Extended

Flyby

Titan IIIC

Direct

Hard

3-day

Flyby (unfueled Mars 71)

Titan IIIC

Direct

Soft

Extended

Flyby

Titan-Centaur

Direct

Hard

3-day

Orbiter

Titan-Centaur

Direct

Soft

3-day

Orbiter

Titan-Centaur

Direct

Hard

Extended

Orbiter

Titan-Centaur

Out-of-Orbit

Hard

3-day

Orbiter

Titan-Centaur

Out-of-Orbit

Soft

3-day

Orbiter

Titan-Centaur

Direct

Soft

Extended

Orbiter

Titan-Centaur

Out-of-Orbit

Hard

Extented

Orbiter

Titan-Centaur

Out-of-Orbit

Soft

Extended

Orbiter

Separate launches for Direct orbiters and landers

Direct

Hard

3-day

Flyby

Direct

Soft

3-day

Flyby

Direct

Soft

Extended

Autonomous

Direct

Hard

Extended

Flyby

Direct

Soft

Extended

Flyby

 
SOURCE: W. I. Watson, " Viking Project Phase B Report, " M73-110-0 [circa Nov 1968] pp. 7-8.
 
....with extended life and an orbiter with a science package. Given expectations at the start of the meeting, the first option was the mission Martin's people expected to get; the second was the one they really wanted. All of the possible mission configurations were debated in an executive session on 9 November. Don Hearth and Robert S. Kramer discussed the dollar implications of the different missions, and Hearth noted that the out-of-orbit mission, at $39 million for fiscal 1970, would cost $10 million more that first fiscal year than the direct-entry mission.
 
Cortright spoke on behalf of a soft landing since the hard-lander apparently could not carry enough science for a realistic mission. He noted that the Langley senior staff preferred the Titan IIIC direct mission, as it was....
 
 

Table 25 [150]

Viking Mission Modes

Examined at 8-9 November 1968 Briefing

Launch Vehicle

Support for Cruise and Relay

Entry Delivery System

Lander

Titan IIIC

Flyby modules

Direct:

Spinning

Hard:

Limited life, relay only
Limited life, relay plus direct link
Extended life, replay plus direct link

New

-

Stabilized

-
Spinner
Stabilized
Lifting
Nonlifting

Mars 71 (unfueled)

-

Titan III- Centaur

 

 

 

 

 

 

Orbiters

Orbital:

Spinning
Stabilized

Soft:

Limited life, relay only
Limited life, replay plus direct link
Extended life, relay plus direct link

New

-

-
Spinner
Stabilized

Mars 71

Minor modification
Major modification for orbital entry

Other:

Autonomous capsules

If no orbiter above is chosen:

Orbiter flown for
orbital science

Orbiter flown for orbitalscience and as relay for lander

Separate launch

SOURCE: Langley Research Center, "Titan Mars 73 Mission Mode Briefing," 7-8 Nov. 1968, p.16.
 
....the most cost-effective and manageable approach and it met scientific needs. With no orbiter to worry about, Langley could concentrate its efforts on the lander. Although a Titan-Centaur orbiter-lander mission would benefit from Mariner technology Cortright did not believe that the smaller lander dispersions-offering more control over the area in which the lander would touch down-promised from such a mission were a significant enough advantage to merit the cost. The addition of an orbiter to the package would not prove a face-saving element should the lander fail, since the lander represented 80 to 90 percent of the project. While the orbiter-lander combination would provide the most scientific information, it was also the most costly and the most complex alternative, both technically and organizationally. Looking at the amount of data that would be returned, Cortright noted that Surveyor had provided over 10 000 photographs, but it had been the first few that had provided the biggest payoff. Since the orbiter-lander [151] approach would cost about $70 million more than the direct entry mode, Cortright believed that the agency should consider the relation between the scientific return and the expenditure. He was not convinced that the extra money would be well spent.
 
John Naugle's concerns lay in another direction: Which proposal would be the easier to sell to Congress and the new administration? Jim Webb had left NASA in October as a prelude to the end of President Johnson's term,. and Thomas O. Paine, Webb's deputy had assumed the reins of the organization as acting administrator. The significant question was what policy toward space activities would the Nixon administration pursue. With Richard M. Nixon elected to the presidency only four days before the high-level agency meeting, Naugle said that the unknowns of a new administration made it difficult to know what to do, especially in light of the criticisms by some scientists that the planetary program had been too conservative. Still, with all the uncertainties, Naugle favored the more complex mission. He believed that the costs of a lander could be reduced below current predictions and an orbiter with new science would enhance the overall mission. The orbiter had two important functions: orbital photography could be used in landing site selection, and the orbiter could serve as an information relay link, significantly increasing the amount of data returned from the Martian surface. The relay link would permit still further exploitation of the growth potential of the soft-lander for landed experiments. Naugle was willing to try to sell this orbiter-lander option to Paine, to the new president, and to Congress.
 
After considerable discussion among the NASA representatives, Don Hearth made the following summary of the mode they should recommend to Acting Administrator Paine:
 
 
This proposal met with unanimous agreement, as did the name of the new project Viking. But on 4 December 1968, NASA announced that Paine and Naugle had selected the more ambitious out-of-orbit option for Project Viking. After listening to the Langley briefing, Naugle believed that an extended life orbiter with new post-Mariner 1971 experiments was essential to Viking. Looking back, Naugle recalled: "It is a little hard to recapture the mood of the times.. .but...one of the things that figured in my mind was the fact that we were in competition with the Russians. They had a good strong program of landers, and I. . . . felt that we had to establish a good solid scientific mission." If "the Russians landed successfully in '71 or '73, what we landed. . . . had to be [152]  something that would stand up against what they had done." Acting Administrator Paine for his part was searching for a successful project for which he could assume responsibility, as most people would consider the manned lunar missions to be the work of NASA's second administrator, Jim Webb. In the autumn of 1968 when Paine looked to the future of NASA's program, he believed in the importance of unmanned planetary exploration and enthusiastically endorsed the Viking project in its most advanced form. 60
 
NASA chose a soft-lander with a "surface lifetime goal of 90 days" for the Mars project. A Mariner 1971-class orbiter would complement the lander science by providing "wide-area surveillance," which could be correlated with surface data from the landing site. The orbiter would also increase the data returned from the surface by providing a relay link between the lander and Earth. In 1968 NASA decided to employ the Titan IIID-Centaur launch vehicle for planetary missions because of its improved payload capacity. With the Titan IIID-Centaur, the lander and orbiter could be boosted together. Once the two craft reached Mars and went into orbit, the lander would be released. This approach to the mission would permit greater accuracy in landing at a preferred site, lower entry velocities, and more control over entry angles, three vital factors that affected lander survival. 61 The Titan IIID-Centaur would also permit the mission reasonable payload weights: 62
 
 

Titan IIIC

Titan IIID-Centaur

Total orbital weight

1136 kg

3400 kg

Lander

360

1000

Scientific experiments

10

30
 
This significantly improved pair of flights-an orbiter and an orbiter lander, launched about 10 days apart-would cost $415 million, up from $385 million for the smaller, less productive mission discussed during the fiscal 1969 hearings. 63
 
After 17 years of promoting, planning, debate, enthusiasm, and despair. NASA could finally get down to the task of designing and building hardware. Although dollars for Viking would always be scarce, this Mars lander would actually journey to the Red Planet. On 6 December 1968, Ed Cortright announced the formation of an interim Viking Project Office at Langley to replace the Advanced Space Project Office (Unmanned):
 
 
Effective this date, the following are reassigned to the interim Viking Project Office in the capacities as indicated:

Project Manager

James S. Martin, Jr.

Deputy Project Manager

Israel Taback

Project Scientist

Dr. G. A. Soffen

Operations Manager

William J. Buyer

Engineering Manager

Israel Taback

[153] Executive Engineer

Angelo Guastaferro

Space Vehicle Manager

Robert L. Girouard

Test Manager

William I. Watson

Asst. Spacecraft Manager

Edmund A. Brummer

Asst. Spacecraft Managers

Royce H. Sproull

Frank E. Mershon

Missions Analysis Manager

Norman L. Crabill 64

 
 
Under the organizational framework set up by Martin and his colleagues, Lewis Research Center would oversee the launch vehicle for Viking, JPL had responsibility for designing and building the orbiter, and Langley would supervise lander and system integration. Following the pattern of Lunar Orbiter, an industrial prime contractor would be selected to develop and build the lander, with Langley personnel members as technical managers. This scheme had been used successfully in numerous other NASA programs, notably the manned spaceflight projects, Mercury, Gemini, and Apollo.
 
Jim Martin opted for a reasonably simple management structure. Responsibility for the project passed directly from the Office of Space Science and Applications at headquarters through Langley's director to the project manager. All other NASA concerns working on Viking reported to Martin, who clearly established himself as the "boss." Three major tasks would dominate the years before the Viking launch: developing and building the orbiter, developing and building the lander, and selecting and building the scientific experiments. And Martin's team in Virginia would make sure that the necessary work was done on schedule and within the budget.