The Langley Group

In 1958 NASA put together an upstart team at its Langley Research Center called the Space Task Group (STG) under the leadership of Robert Gilruth, the pioneer of flying qualities research. Gilruth assembled twenty-five young Langley engineers willing to stake their careers on a risky endeavor.21 They focused on the capsule itself;the Redstone rocket to loft it into space would be supplied by von Braun's group in Alabama. The Germans had spent more than twenty years building and flying rockets without human occupants. Similarly, the Atlas booster that would fly the orbital Mercury flights was built by Convair for the air force—founders of the West Coast ICBM culture focused on systems engineering and automatic control. In contrast to these newfangled systems types, many of the young engineers in Gilruth's Space Task Group had technical backgrounds in flight control and had worked closely with test pilots for much of their careers. The STG formed the core of what would soon become NASA's Manned Spacecraft Center in Houston, with Gilruth as its first director.

Since 1945 Gilruth had headed the Pilotless Aircraft Research Division (PARD) at Wallops Island, Virginia. The group's name sounded ominous for pilots, but these were hands-on engineers who flew things. PARD engineers began firing rockets at hypersonic speeds to create aerodynamic conditions that the day's wind tunnels could not mimic. Fourteen of the original STG engineers came from this group, including Max Faget, who designed the shapes for the Mercury, Gemini, and Apollo capsules, and even for the space shuttle.22

The remainder of the original STG came from NACA groups in instrumentation, flight testing, and stability and control (along with a group of Canadian aircraft engineers laid off from the Avro company, in part because their government chose to rely on missiles rather than aircraft for air defense). These research and design engineers had roots in flight control and piloting and included a number of men, in addition to Faget, who would go on to become household names in the American program. Cald-well Johnson, who worked closely with Faget, recalled incorporating pilots' opinions into design decisions, ''as a result of the background I had in aircraft work, I brought into play the pilot and aircraft aspects of the system.''23 Chris Kraft had cut his teeth under Hewitt Phillips at NACA Langley in flight test, instrumentation, and telemetry.24 The shrewd, technical Kraft remembered that when the STG began working on Mercury, they were ''still thinking in airplane terms''—that is, giving the astronaut everything he needed to know to fly the rocket. ''But it quickly became obvious from Air Force input that things happened so fast in rocketry that an astronaut couldn't do anything anyway.''25

Gilruth's group also included the man who would drive the inclusion of a digital computer in Apollo. Robert Chilton had flown B-17 bombers during World War II and then earned bachelor's and master's degrees at MIT, studying under Stark Draper and Robert Seamans. He spent ten years at Langley in the Stability and Control branch working with Hewitt Phillips and his assistant Charles Matthews (who went on to become Gilruth's assistant on Mercury). Among other projects, Chilton used control theory to make mathematical models of the responses of a human pilot.

Chilton helped specify the Mercury control system and selected and oversaw the contractor to incorporate it into the spacecraft. For Mercury, Chilton conceived that ''the pilot would perform a balanced role,'' of a variety of control, monitoring, and abort functions. Yet the pilot's primary job, in Chilton's view, was ''being the captain of the ship and not just the pilot.''26

A philosophy began to emerge: during normal operation, the control loops would be automatic, stabilized by feedback controls. If the primary systems failed the pilot would take over. The consequence was that in an emergency, the pilot's workload went up, because then he would rely on simple, less-automated backup systems that were presumably more reliable than the automatic systems.27 ''If the pilot had to take over [in Mercury], which we didn't think he would...he would just simply use his controls to zero, null these needles and help him maintain attitude, and look through the periscope just like centering the bubble.'' Nevertheless, Chilton recalled, the astronauts didn't like the idea—''they wanted to fly the thing.''28 As John Glenn told a press conference soon after his selection to the Mercury team, ''We don't want to just sit there and be just like a passenger aboard this thing. We will be working the controls.''29 Nevertheless, the automatic-as-primary approach would survive through Apollo.

One other man joined the STG with a unique point of view. Robert Voas was trained as a psychologist, and he worked for the navy studying ''human engineering'' or ''ergonomics'' for pilot selection, training, and operations. The navy assigned him to the STG at its founding, and he immediately began working on the role of the pilots.30

Voas realized that the question of pilot involvement bore heavily on the selection and training of the astronauts. Technical decisions had human implications: what the operator needed to do affected who would be chosen. ''Was this just someone along for the ride,'' he stated, ''or were they expected to be a very significant part of the opera-tion?''31 Voas deemed that individuals with physical fitness and experience operating technical systems would fit the bill (a decision he later regretted, because he found the Mercury Seven deficient in engineering skills).32 Nothing in these original qualifications necessitated experience in aviation. On Voas's recommendation, NASA approved a set of selection criteria that might include ''test pilot, crew member of experimental submarine, or arctic explorer.'' NASA was ready to go public with an announcement, but at the last minute President Eisenhower decreed the astronaut candidates should be chosen from the ranks of military test pilots—for both security and secrecy reasons.33 (Such limitations alone, however, should not have excluded submariners.)

The Mercury astronauts distrusted Voas, as they did human factors experts in general, whom they classified with an old pilots' enemy—flight surgeons. One NACA engineer referred to ''industrial psychology and human factors'' as ''dirty words around here.'' Chris Kraft thought Voas ''wasn't nearly as good as his advance notices.''34

But Voas did strongly advocate for the human role, ''to have a man in space and not just send up empty spacecraft that were completely automatic.'' Because a Mercury flight ''begins and ends with periods during which the astronaut does not control the vehicle's attitude or flight path,'' wrote Voas, the human role in Mercury had been ''underestimated.''35 Voas called the astronaut ''not a mere passenger, but an active controller of the vehicle'' and argued that human intervention in control loops (along with ample displays of information) improved the flexibility and robustness of the system. ''The astronaut operates as an integral part of the Mercury system,'' Voas con-

eluded, and pointed out that Mercury would show ''man's proficiency as a controller for space vehicles.''36

Voas listed seven roles for the Mercury astronauts, in order of priority: (1) ''systems management,'' which mainly involved monitoring the automatic systems;(2) ''programming'' or ''sequence monitoring,'' which involved monitoring critical events during launch and reentry;(3) controlling vehicle attitude;(4) navigation;(5) commu-nications;(6) research observations;(7) keeping attentive and fit under flight stresses; and (8) ground preparation. The pilot functioned either as a backup system himself, or as a switcher who enabled backup systems to come into play. For example, if the sequencers were to go awry, ''he must substitute himself for the malfunctioning automatic programmer,'' a task more subtle and demanding than simply responding to green and red lights like a laboratory mouse (although that is how the task might have appeared to an observer).37 Voas mapped the manual and automatic functions and the numerous ways that a given task could be divided between the two (figure 4.4).

Voas participated not only in the selection process, but also in shaping the innovative training regimen for Mercury. Again, training depended on what would be expected of the astronauts while in orbit; both changed over the course of the program. While Voas and his colleagues had deep experience in flight training, for Mercury the goal became as much to condition the astronauts not to do things (in panic or erroneous response), as it was to train them for positive actions. It also sought to condition their responses to the physical and psychological stresses of spaceflight. Because the astronauts were seen as redundant backup systems, knowing the spacecraft systems and being able to detect and diagnose failure became primary objectives.38

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