The first true pilots spacecraft

Notwithstanding Mercury's triumphs of human control, rhetorical or practical, Project Gemini began to fulfill von Braun's vision: pilots as monitors during launch, but in the loop while in orbit. Gemini planners sought to explore longer-duration spaceflight, learn how to rendezvous and dock, achieve precision landings, establish the capability for ''extra vehicular activity'' or EVA (colloquially referred to as ''space walking''), and provide additional experience for flight and ground crews in manned spaceflight. Woven throughout these objectives—from orbital maneuvering to accurate reentries—was the desire to expand human control.

The Mercury capsule had been heavily dependent on sequencing devices, even with the human in the loop. Gemini simplified the system by putting much of the sequencing responsibility onto the human operator and providing numerous new thrusters and tools for control. Unlike Mercury, the Gemini spacecraft could not be controlled from the ground without significant additional equipment.53 Inside, the human operator stood at the nexus of an inertial platform, an optical tracker, and a digital computer—an assemblage that set the stage for Apollo.

In late 1962, before Gemini flew, Gus Grissom visited the SETP to explain the new program and to contrast it with Mercury. He now characterized the earlier project as containing a passive human passenger. ''The most important difference,'' Grissom told his colleagues, ''is the amount of control the pilot exercises over all functions.'' In Mercury, pilots could contribute to the mission, Grissom continued, only by manually overriding automatic systems. ''Until now, man has been a self-experimenting guinea pig.'' By contrast, ''Gemini is the first true pilot's spacecraft,'' he claimed, allowing the astronaut to step into his new role as ''the explorer of space.'' Grissom argued that Gemini would require the pilot's responses at all times, from his finger on the abort button during boost to his judgment about the time and location of reentry. ''Gemini will be a pilot controlled operational spacecraft, not just a research and development vehicle.'' Grissom pointed forward to a change in professional identity: ''the test pilot will have stepped into his proper role—the explorer of space.''54 Given the controversy that surrounded his botched recovery on Mercury, Grissom had some interest in portraying the role of the Mercury astronaut as something less than totally in control.

Unlike Mercury, where the craft reentered the atmosphere in an open-loop, ballistic fashion, Gemini would be steered by the pilot right down to the point of landing—yes, landing, a proper return worthy of a pilot's dignity. The Gemini capsule would spring a special parachute shaped like a hang glider. Under this ''paraglider'' control, the pilot would ''fly'' down from the last few thousand feet, deploy a few skids from the underside of the capsule, and land on a runway. ''The paraglider will be controlled by either pilot,'' Grissom explained, ''with the same hand controller he used in orbit...the pilots will have to locate the landing area on their own.'' The paraglider's sluggish handling qualities would call for the greatest skill.55 Guidance and control would assume new importance, both for getting the pilot to the point of rendezvous, and for selecting and navigating to a landing site.

Reporting on the SETP meeting, the New York Times echoed Grissom's words with a front-page story in 1962 under the headline ''Pilots will control Gemini spacecraft.'' The story described how after Mercury, NASA would be ''reverting to the concept of a pilot-controlled aircraft'' for Gemini. ''The Gemini capsule will be under the control of the astronauts rather than automatic instruments.''56 Where Mercury had been fully automated out of concern for possible degradation of pilot abilities in space, the program had proved the pilots' abilities and Gemini would take full advantage of them. Advancing technology would mean not more automation, but more human control.

As the tasks and technology changed, the crews evolved as well. Grissom was in the minority: of the seventeen men who flew on Gemini, only three came from the original Mercury Seven. The remainder came from subsequent sets of astronauts in the second (''the new nine'') and third (fourteen) groups of astronauts. These men tended to have higher levels of education and greater technical skills in addition to their testpilot backgrounds, reflecting the changing nature of their tasks and a new NASA emphasis on professional training over physical characteristics.

The ten Gemini missions did indeed fulfill Grissom's hopes and von Braun's vision of astronauts as active, on-orbit controllers. The first Gemini flights, unmanned in April 1964 and January 1965, flew suborbital and required a special sequencer installed in the astronaut's couch to put the craft through its paces. On the first manned Gemini mission (Gemini III, March 1965), Grissom maneuvered the spacecraft with its new set of thrusters, changing not only its orientation (as on Mercury) but also its velocity, dropping the orbit down about thirty miles, which Mercury could not do.

During rendezvous, the pilots flew a ''final approach,'' in an analogy to landing an aircraft, and carefully maneuvered into close proximity with another vehicle. Astronauts practiced rendezvous with spent booster stages on several flights, with varying degrees of success. Then, Gemini VI ( piloted by Wally Schirra and Thomas Stafford) and Gemini VII (Frank Borman and Jim Lovell) achieved a dramatic first rendezvous between two manned craft, four pilots in all. From separate launches more than ten days apart, the pilots maneuvered the two craft within inches of each other, ''window to window and nose to nose.'' Schirra, commander of Gemini VI, emphasized in his memoir his ability to control the spacecraft: ''Using what I called my 'eyeball ranging system,' I did an in-plane flyaround of Gemini 7, like a crew chief inspecting an aircraft ...I was amazed at my ability to maneuver, controlling attitude with my right hand and translating in every direction by igniting the big thrusters with my left hand mechanism.''57 Dramatic photographs of manned spacecraft from the outside highlighted the new, active role of people in space.

Subsequent Gemini missions accomplished rendezvous on different orbits (including the first one after launch, simulating a launch from the lunar surface), from orbits equal, below, or above the target vehicle, and using several different techniques, including with an unmanned target vehicle called Agena. Some of these exercises were designed to simulate maneuvers and abort modes anticipated for lunar missions, some with failures of various parts of the system.

Gemini's project summary concluded that ''the extensive participation of the flight crew in rendezvous operations is feasible.''58 The pilots liked docking;it allowed them to fly.

Technical and budgetary problems had forced the cancellation of the paraglider and with it hopes for controlled, terrestrial landing, so Gemini craft came down in the water as Mercury had. Still, Gemini pilots could maneuver during reentry. Because of its offset center of gravity, the spacecraft's roll determined the direction of lift during a critical few minutes in the atmosphere. By rolling the spacecraft to cancel or reinforce lift, the pilots could effectively control the splashdown point by up to three hundred miles down range and more than twenty-five miles side to side. Continuously rotating the spacecraft would null the lift altogether, and make for the shortest landing. Gemini missions came down within a wide range of distances from their aiming points; some were off by nearly one hundred miles (Gemini V) but a majority were within ten miles of their targets. Ten of the twelve Gemini reentries were flown with a pilot's hand on the stick.59

Gemini also produced its share of anomalies and human responses hailed as critical or heroic. On Gemini VI, with Wally Schirra and Tom Stafford in the cockpit, the launch sequence initiated but shut down prematurely. Rather than issuing an abort, in which the pilots would have dangerously ejected sideways from the spacecraft, ruining it, against established procedure Schirra kept his finger off the abort handle. He sensed that the vehicle had not moved, even though the mission clock had started, and he did not fire the ejection, avoiding the risky bailout and saving the capsule and the rocket for another day. His quick thinking was hailed as a triumph of man in the loop as he spontaneously violated an erroneous mission rule.60

On Gemini VIII, when docked with the Agena target vehicle, the spacecraft started spinning out of control. Astronauts Neil Armstrong and David Scott immediately undocked from the Agena, only to find that the problem was with their own spacecraft and not the target, and they began spinning faster. They isolated a stuck thruster while in a life-threatening tumble, and immediately aborted the mission and landed in the Pacific. Questions arose about whether the immediate undocking was the right decision, but Houston praised the astronauts and explained the situation to validate their decision. On Gemini XII, the rendezvous radar failed and Buzz Aldrin called on manual techniques to perform the rendezvous. By coincidence, he had written his MIT dissertation on pilot-oriented techniques for rendezvous in the absence of automation.61 Numerous other systems failures led to successful recoveries or real-time mission replanning.

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