Fwd: The First Rendezvous in Space

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From: "Gary Johnson" <gjohnson144@comcast.net>
Date: December 17, 2013 7:31:51 PM CST
To: "Gary Johnson" <gjohnson144@comcast.net>
Subject: FW: The First Rendezvous in Space

 

 

AmericaSpace

For a nation that explores
December 14th, 2013

Of Minds & Men: The First Rendezvous in Space (Part 1)

By Ben Evans

 

Gemini VII, bearing astronauts Frank Borman and Jim Lovell on a record-breaking 14-day mission, is seen through the windows of Gemini VI-A, with fellow spacefarers Wally Schirra and Tom Stafford. This mission, in December 1965, marked the first 'true' rendezvous between two piloted vehicles in orbit. Photo Credit: NASA

Two weeks before Christmas in 1965, a pair of Gemini spacecraft—sleek little black-and-white capsules, which John Young once dubbed "Gusmobiles"—serenely circled the Earth together and in close proximity. Aboard Gemini VII, astronauts Frank Borman and Jim Lovell were midway through a record-breaking 14-day mission to spend the equivalent of a long-duration lunar voyage in Earth orbit, whilst aboard Gemini VI-A fellow astronauts Wally Schirra and Tom Stafford had taken the lead in executing the world's first rendezvous between a pair of piloted vehicles in space. It was a critical step toward achieving the late President Kennedy's goal of human bootprints on the Moon before 1970. Although the Soviet Union had managed to bring two spacecraft close together during the Vostok era, they had not performed true rendezvous. Yet the Gemini success came at the end of two disappointing months which saw a rocket explode, a pair of manned missions combined into one, a vice president fall asleep in the simulator … and a hairy on-the-pad launch abort which could easily have spelled death for Schirra and Stafford.

Flying for longer periods in space, according to flight surgeon Chuck Berry, had "qualified man to go to the Moon." In August 1965, astronauts Gordo Cooper and Pete Conrad returned in good physical shape after eight days in orbit. Next up, in late October, Schirra and Stafford would spend just two days aloft, but would actively bring their Gemini VI craft close to a Lockheed-built Agena-D target vehicle, launched atop an Atlas booster. The importance of the flight was such that both the prime crew and their backups, Gus Grissom and John Young, were highly experienced. Although it would be Tom Stafford's first mission, he was already recognized as an expert in space rendezvous. Having said this, Grissom wanted command of the first Apollo mission and pursued it relentlessly. In his autobiography, We Have Capture, Stafford noted that although Young sat through simulations with them, Grissom was often absent, racing cars or boats. Following Gemini VI would come the 14-day Gemini VII, sometime early in 1966, with Borman and Lovell.

All that changed on 25 October 1965.

Although the so-called Gemini-Agena Target Vehicle (GATV) was a fundamental aid in demonstrating rendezvous, docking, and performing linked exercises in space, doubts about its reliability were prevalent within NASA. Some managers felt that it could not be trusted to execute maneuvers with a docked Gemini, although Wally Schirra lobbied for it to fly. He also wanted a firing of the Agena's less powerful secondary propulsion system, although this was not initially incorporated into the Gemini VI flight plan.

Wally Schirra, pictured during training for Gemini VI. On most occasions, he was joined by crewmate Tom Stafford in the pilot's seat of the simulator … but on one unforgettable day he hosted Vice President Hubert Humphrey, with humorous consequences. Photo Credit: NASA

First up would be the Agena, mounted atop its Atlas rocket, from Cape Canaveral's Pad 14, boosted into a 200-mile (320-km) circular orbit. One hundred minutes later, Schirra and Stafford would follow aboard Gemini VI from Pad 19, their Titan II injecting them into a lower orbit. "Two hundred and seventy degrees behind the Agena," wrote Stafford, "you'd make a series of maneuvers that would eventually raise the orbit of the Gemini to a circular one below the Agena. Then you'd glide up below the Agena on the fourth revolution. At that time the crew would make a series of maneuvers to an intercept trajectory, then break to station-keeping and docking." This docking would occur over the Indian Ocean—some six hours into the mission—and after which Schirra and Stafford would remain linked for seven hours and return to Earth following their battery-restricted two-day flight. The astronauts wanted to relight the Agena's engine whilst docked, but NASA managers vetoed it as too ambitious.

The rendezvous, Schirra explained years later, utilised the Hohmann Transfer: "the most efficient, quickest, and prettiest way to do a rendezvous. But it is also intolerant of error. If you blow the rendezvous, fuel and time constraints won't permit another try." During their training in the second half of 1965, the astronauts practiced manoeuvres again and again, plotting them on boards. In total, they did more than 50 practice runs and spent hours rehearsing the docking with the Agena in a Houston trainer. "Housed in a six-story building," wrote Schirra in his memoir, Schirra's Space, "it consisted of a full-scale Gemini cockpit and the docking adaptor of the Agena. They were two separate vehicles in an air-drive system that moved back and forth free of friction. We exerted control in the cockpit with small thrusters, identical to those on the spacecraft. We could go up and down, left and right, back and forth. The target could be maneuvered in those planes as well, though it was inert. It would move if we pushed against it, just as we assumed the Agena would do in space."

On one occasion, Schirra hosted Vice President Hubert Humphrey in the pilot's seat. Humphrey asked if their voices could be heard from outside the trainer. When Schirra replied that it was sound-proofed, Humphrey asked if Schirra minded him taking a nap. When Humphrey awoke, he asked Schirra to tell him what had happened so that he could tell the people outside. "I was a fan of Hubert Humphrey from that day on," wrote Schirra.

Gemini VI was the last of the series to run solely on battery power, thus limiting the two astronauts to no more than 48 hours in space. Although by September 1965 NASA was pushing for just one day aloft, if all objectives were completed. "Secondary" experiments were kept to a barebones minimum. Schirra's attitude was that rendezvous was a significant challenge and left no time to "play" with experiments.

Early on 25 October, out at Pad 14, a team from General Dynamics oversaw the final hours of the Atlas-Agena countdown. The Atlas booster, tipped with the thin, pencil-like Agena, was scheduled to fly at precisely 10:00 a.m. EST. Meanwhile, Schirra—who was struggling to give up smoking—lit up a Marlboro during the ride to Pad 19. He felt, wrote Stafford, that "he could survive a twenty-four-hour flight without getting the shakes." At length, General Dynamics launch manager Thomas O'Malley pressed the firing button for the Atlas-Agena at 10:00 a.m., and the first half of the mission got underway.

The Gemini VI spacecraft (right) and its Agena target vehicle undergo boresighting tests ahead of their separate launches. Photo Credit: NASA

Or so it seemed.

There seemed little reason to doubt that the Agena would fly perfectly. The countdown had gone well. The Agena had a heritage of 140 previous flights since 1959, and its reliability was very good. It would separate from the Atlas high above the Atlantic Ocean, then fire its engine over Ascension Island to boost itself into orbit. Finally, at 11:41 a.m., Schirra and Stafford would ride their Titan into space to initiate the rendezvous.

Almost immediately after the Atlas-Agena lifted off, things started to go catastrophically wrong. It would appear that the Agena separated properly from its carrier rocket, but seemed to "wobble" a little, despite the efforts of its attitude-control mechanism to steady it. Right on time, its engine flared to life … and nothing more was heard. It had reached an altitude of about 150 miles (240 km) and was 500 miles (800 km) downrange of the Cape. Fourteen minutes after liftoff, specialists at the Bermuda radar station expected to receive tracking. They saw nothing, save the signatures of five large fragments.

Out at Pad 19, Schirra and Stafford were listening to the updates and were puzzled. "Maybe it's the tracking station," Schirra speculated. "Let's wait for Ascension Island." Their countdown was held, but at length Ascension, too, saw nothing. Later, the Carnarvon station in Australia saw nothing, and the assumption had to be made that the target vehicle had been lost. Subsequent investigation revealed that the Agena had exploded, due to a pre-launch change in the oxidiser feed sequence protocol. If it represented a programmatic failure with the vehicle, the issue spelled trouble for Project Gemini, which depended upon the Agena as its primary rendezvous target. In the meantime, a disappointed Schirra and Stafford were extracted from Gemini VI and headed off into town with Chief Astronaut Al Shepard and backup crewman John Young.

"Boys," Shepard told them, "what we need is a good party!"

A new Agena would not be ready until early 1966, but a perfect alternative lay on the horizon. Immediately after the Agena's loss, Frank Borman overheard a conversation between McDonnell officials Walter Burke and John Yardley: the former suggested launching Gemini VII as Schirra and Stafford's "new" docking target. A study of sending Geminis up in quick succession had been done months earlier and seemed ideal, but for one thing. Burke sketched his idea onto the back of an envelope, but Borman doubted the practicality of installing an inflatable cone onto the end of Gemini VII to permit a physical docking. Several senior NASA managers, including George Mueller and Charles Mathews, dismissed the entire idea, since it would require the launch of both Geminis within an impossibly tight two-week period.

Others thought it could be done. Joseph Verlander and Jack Albert proposed stacking a Titan II and placing it into storage until another had been assembled. The Titan's engine contractor, Aerojet-General, had stipulated that the vehicle must remain upright, but this could be achieved and the rocket kept on the Cape's disused Pad 20. Immediately after the first Gemini's launch from Pad 19, the second Titan could be moved into position and sent aloft within a week. The plan, however, held little appeal and received little enthusiasm, with most attention focused on swapping the lighter Gemini VI for the heavier Gemini VII, thereby making good of a bad situation by using the Titan II already on the pad to fly Borman and Lovell's 14-day mission.

Flight controllers—with Flight Director Chris Kraft seated at center—watch their monitors in dismay after the loss of the Agena on 25 October 1965. The incident led to the development of a new plan to fly a rendezvous mission between two manned craft, Gemini VI-A and Gemini VII. Photo Credit: NASA

Over the following days, as this was discussed in the higher echelons of NASA management, it became evident that if the two spacecraft were swapped, the earliest that Borman and Lovell could be launched would be 3 December 1965. However, if the Gemini VII spacecraft was too heavy for Gemini VI's Titan, a delay until around 8 December would become necessary to erect the more powerful Gemini VII Titan. It was then envisaged to launch Schirra and Stafford on their rendezvous mission with another Agena sometime in February or early March 1966.

As these plans crystallized, Burke and Yardley posed their joint-flight idea to senior NASA officials, who found few technical obstacles, with the exception that the Gemini tracking network might struggle to handle two missions simultaneously. At first, Flight Director Chris Kraft thought they were out of their minds, but after consulting his control team and Deke Slayton, the head of Flight Crew Operations, relented. The prospects for Burke and Yardley's plan steadily brightened when it became clear that the heavy Gemini VII—which, after all, was intended to support a mission seven times longer than Gemini VI—could not be lofted into orbit by Schirra and Stafford's Titan: the booster lacked the necessary impulse. Yet the question of tracking two vehicles at the same time remained. Then, another possibility was aired. Could the tracking network handle the joint mission if Gemini VII were regarded as a "passive" target for Gemini VI? Borman and Lovell would launch first and control of their flight would proceed normally as Gemini VI was prepared to fly.

As soon as controllers were sure that Gemini VII was operating satisfactorily, they would turn their attention to launching Gemini VI; in the meantime, Borman and Lovell's flight would be treated like a Mercury mission, wrote Deke Slayton, "where the telemetry came to Mission Control by teletype, letting the active rendezvous craft have the real-time channels that were available." This mode would continue until "Gemini VI-A"—renamed to distinguish it from the original Agena-based mission—had completed its tasks and returned to Earth. After Schirra and Stafford's splashdown, Borman and Lovell would again become the focus of the tracking network.

Wally Schirra and Tom Stafford, shown here preparing to board Gemini VI for their ill-fated 25 October 1965 launch attempt, would eventually fly in mid-December, after a hair-raising abort of the Titan II's rocket main engines. Photo Credit: NASA

Before NASA Headquarters had even come to a decision, the rumor mill had already informed the press, some of whom reported the possibility of a dual-Gemini spectacular. On 27 October, Administrator Jim Webb and his senior staff discussed the idea and issued a proposal for the joint flight to the White House. He informed President Lyndon B. Johnson that, barring serious damage to Pad 19 after the Gemini VII launch, Schirra and Stafford's Titan could be flown within days to rendezvous with Borman and Lovell. Johnson, residing at his ranch in Austin, Texas, approved the plan on 28 October, and his press secretary announced it would fly in January 1966. At NASA, however, December 1965 was considered more desirable.

As October turned to November, preparations gathered pace. Gemini VI-A's Titan was destacked and placed in bonded storage under plastic covers, and the heavy-lift Titan for Gemini VII was erected in its place. Pad Leader Guenter Wendt's first reaction when he saw the short, nine-day Gemini VI-A pad schedule was "Oh, man, you are crazy!" Although Schirra and Stafford's mission would essentially not change, that of Borman and Lovell was slightly adjusted to circularize its orbit and mimic the Agena's flight path as closely as possible. Yet their own mission was fraught with great risk.

Since their assignment to Gemini VII, Borman and Lovell had been intensely focused on their primary objective: to spend 14 days (330 hours) in space, thereby demonstrating that astronauts could physically and psychologically withstand a maximum-length trip to the Moon and back. The results from the two previous long-duration flights, Gemini IV and Gemini V, had been mixed. Jim McDivitt and Ed White had returned fatigued after four days, while Gordo Cooper and Pete Conrad had hardly enjoyed their eight days sitting in an area the size of the front seat of a Volkswagen Beetle. Sleeping in shifts of four or five hours apiece had proven impractical, Borman and Lovell learned, so they resolved to sleep and work together. Moreover, they felt that their "work" time would not benefit from a rigid plan, opting instead for a broader outline which they could adapt in orbit.

At 2:30 p.m. EST on 4 December 1965, Gemini VII roared into orbit. "We're on our way, Frank!" yelled Lovell as the Titan rolled and pitched in its ascent trajectory, achieving orbit five and a half minutes later. After a station-keeping exercise with the Titan, they settled down to eight days of experiments, ahead of the launch of Gemini VI-A and the rendezvous. As the flight wore on, conditions became increasingly less comfortable, with both men complaining of stuffy noses and burning eyes. The cabin, Borman reported, was too warm. Removing their suits helped, yet even that had been a matter of some debate on the ground. Days earlier, on 29 November, Bob Gilruth had requested approval from NASA Headquarters for the astronauts to remove their suits after the second sleep period and only don them at critical junctures, such as rendezvous and re-entry. By the time Gemini VII launched, the plan had been amended slightly: one of them had to be suited at all times, but the other could remove his garment for up to 24 hours. Both men, however, had to be fully-suited for rendezvous and re-entry. Still, the intense discomfort was there and, as the mission wore on with no major issues, the rationale behind the one-suit-on/one-suit-off decision became unsupportable.

This fish-eye view of the interior of Gemini VII reveals the limited space available to Frank Borman and Jim Lovell during their 14-day mission. Within this cramped volume were not only the men themselves, but their food, experiments, cameras … and bags for their bodily wastes. Both astronauts likened it to living for two weeks in a men's room. Photo Credit: NASA

Even with his suit unzipped and gloves off Borman sweated heavily, while the unsuited Lovell remained dry. After 24 hours, Lovell asked to sleep unsuited, to which Borman agreed, despite his own discomfort. Lovell, the larger of the two, had more difficulty getting out of his suit in the confined cabin and, although he donned some lightweight flight coveralls for a few minutes, he removed them just as quickly, due to the intense warmth.

After four days of this torment, Borman asked the flight controller on the Coastal Sentry Quebec tracking ship to ask Chris Kraft about the chances of both men taking off their suits. Capcom Gene Cernan discussed the request, firstly, with Deke Slayton, before approaching Kraft, but there was little option but to ask Lovell to put his suit back on so that Borman could remove his suit. Concern was mounting, however, about how alert the astronauts would be for the Gemini VI-A rendezvous if they were so hot and uncomfortable. Bob Gilruth certainly favoured both men having their suits off at the same time, and Chuck Berry, looking at the biomedical data, saw clear signs that blood pressures and pulse rates were closer to normal when Borman and Lovell were unsuited. Eventually, on 12 December—the very day that Schirra and Stafford were due to fly—NASA Headquarters finally agreed to allow the Gemini VII crew to remove their uncomfortable suits.

The astronauts' patience was, however, tried on a number of occasions—most notably when a urine bag broke in Borman's hands. "Before or after?" asked Chuck Berry. When Borman affirmed it was after, Berry replied "Sorry about that, chief." After the flight, Lovell would describe their living and working conditions in a similar manner to Cooper and Conrad: like sitting in a men's toilet for a fortnight without access to a shower. This did not bode well for the physicians. After splashdown, one of their tasks was to examine calcium loss in space, and they would be obliged to not only sift through Borman and Lovell's liquid and solid waste, but also microscopically analyse the contents of their underwear. …

In the meantime, Wally Schirra and Tom Stafford's Gemini VI-A Titan had been raised on Pad 19 on 5 December. A computer problem quashed hopes to launch on the 11th, but the prospects were bright for a second attempt the next day. Launch was scheduled for six seconds past 9:54 a.m., and the countdown clock ticked perfectly toward an on-time liftoff. Precisely on cue, the Titan's first-stage engines ignited with a high-pitched whine.

Clouds of smoke hang ominously around Pad 19 as Gemini VI's Titan sits motionless in the seconds after the abort. Note the absence of an escape tower atop the Titan; in an emergency, Schirra and Stafford would have used ejection seats. Many astronauts doubted the reliability and survivability of the seats, which factored into Schirra's decision not to use them that day. Photo Credit: NASA

Then, after less than 1.2 seconds, they shut down.

Instantly, Schirra, his hand clasping the D-handle to fire their ejection seats, faced a life-or-death decision. The mission clock on the instrument panel had started running—as it would in response to the vehicle lifting off—but he could feel no movement. If the Titan had climbed even a few inches, there was a very real risk that its full load of volatile propellants could explode in a holocaust. In his autobiography, Stafford remembered vividly the moment that the behemoth came alive and, just as vividly, the instant at which its roar ceased. "The sound of the engines died even though the clock started and the computer light came on, both indications that we had lifted off," he wrote. "But I could feel that we hadn't moved. More important, there was no word from [Capcom] Al Bean confirming liftoff, which was critical." In fact, it was the feeling of stillness that convinced Schirra not to risk ejecting.

Kenneth Hecht, head of the Gemini escape and recovery office, was surprised that he did not eject, but in reality, neither Schirra nor Stafford had much confidence in the seats and instinctively desired to remain with their "bird" as long as possible. Stafford felt that the 20-G acceleration of an ejection would have left him with, at best, a cricked neck for months. Moreover, there was a very real risk of death.

Yet Schirra would not have put them in any undue danger. "If that booster was about to blow," he said, "if we really had a liftoff and settled back on the pad, there was no choice. It's death or the ejection seat."

 

Copyright © 2013 AmericaSpace - All Rights Reserved

 

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AmericaSpace

For a nation that explores
December 15th, 2013

Of Minds & Men: The First Rendezvous in Space (Part 2)

By Ben Evans

 

Beautiful view of Wally Schirra and Tom Stafford's Gemini VI-A spacecraft, viewed by astronauts Frank Borman and Jim Lovell aboard Gemini VII. Schirra's gutsy decision to sit tight after the 12 December pad abort ensured that this historic rendezvous mission could go ahead. Photo Credit: NASA

"It's death … or the ejection seat!" For Wally Schirra, command pilot of Gemini VI-A, steely nerves were a mainstay of his career as a naval aviator and as one of America's first astronauts.

As noted in yesterday's history article, on the morning of 12 December 1965, aboard the tiny black-and-white spacecraft with his crewmate Tom Stafford, the countdown clock ticked to zero, the twin engines of the giant Titan II booster roared to life … and abruptly shut down. Clasping the D-handle which would have fired both of their ejection seats, Schirra was faced with a life-or-death decision. If he pulled the handle, he might—only might, for the seats themselves were inherently dangerous—save their lives at the risk of eliminating any chance to complete NASA's goal of a manned orbital rendezvous before the end of 1965. On the other hand, if he didn't pull the handle, Schirra and Stafford might survive … or perhaps meet their maker in a holocaust of flame as the Titan's volatile load of propellants exploded. He elected to stick with his craft, and he and Stafford lived to fly another day.

"Schirra," wrote fellow astronaut Gene Cernan, "had balls." Indeed he did.

In emotionless tones, Schirra reported that propellant pressures in the Titan were dropping and test conductor Frank Carey responded with "Hold Kill" to denote that a shutdown had indeed occurred. When the smoke had cleared, and after receiving assurances that the ejection seat pyrotechnics had been safed, Pad Leader Guenter Wendt and his team returned to Pad 19 and Gemini VI-A to begin extracting the two disappointed astronauts. "It took 90 minutes to raise the erector and get us out, a lot longer than it should have," wrote Stafford in his memoir We Have Capture. "Although he had kind words for Guenter and the pad crew, Wally was furious." The families of the two men were also understandably anxious, and from then onward it would become standard practice to have another astronaut present with them during a launch attempt. The day itself was already a bad one: a Cape Kennedy rescue helicopter had crashed in the nearby Banana River, and Dr. Randy Lovelace—bane of the astronauts' lives during their selection, courtesy of his invasive Lovelace Clinic—and his wife had been tragically killed in a private aircraft crash in Aspen, Colo.

A disappointed but relieved Tom Stafford (left) and Wally Schirra depart Pad 19 after the 12 December pad abort. Their quick thinking and actions that day helped to ensure that they could be quickly recycled to launch a few days later … and saved the rendezvous mission. Photo Credit: NASA

Later that very same afternoon, President Lyndon B. Johnson told NASA Administrator Jim Webb that he had been "greatly disturbed" by the launch abort, although he was assured that enough time still remained to identify the Titan glitch, fix it, and then get Gemini VI-A into orbit before the end of Frank Borman and Jim Lovell's Gemini VII mission. That glitch did not take all that long to find: an electrical tail plug had dropped prematurely from the base of the rocket and activated an airborne programmer—a clock in Gemini VI-A's cockpit which should not have started until liftoff. The plug had rattled loose from its housing. Although the plug had been installed properly, tests revealed that some plugs did not fit as snugly as others and that they pulled out much more easily.

Then, as engineers pored over engine trace data, it became clear to Ben Hohmann of the Aerospace Corporation that the Titan's oxidizer pressure and overall thrust had begun to decline before the plug fell out. Subsequent analysis identified a blockage in the gas generator and, eventually, an Aerojet technician found the answer: a thimble-sized dust cover had been left on its fuel inlet port during processing. Months earlier, when the engine was still at Martin's plant in Baltimore, the gas generator had been removed for routine cleaning, and when the check valve at its oxidizer inlet was detached, a plastic cover was installed to keep dirt out. As checkout of the engine proceeded, the dust cap was overlooked and forgotten. To be fair, its location would have been almost impossible to find. However, had the initial tail plug dropout not stopped the launch, the gas generator blockage certainly would have. "It was serendipitous that we shut down," said Joe Wambolt, then a Gemini propulsion engineer, in an interview published years later in Quest magazine, "because the other engine was not going to thrust."

In his autobiography, Wally Schirra wrote that, had he known of this "second" brewing problem at the time, he probably would have chosen to fire the ejection seats.

As well as demonstrating the steely nerves of the Gemini VI-A crew—one of Schirra's first messages had been "We're just sittin' here breathing"—the abort also verified, in the most dramatic manner possible, that the Titan's malfunction detection system worked. Sensing no upward movement, it had correctly and automatically closed the valves to prevent more fuel entering the combustion chambers and had duly shut down the engines. Catastrophe had been averted, and Gemini VI-A rose spectacularly into orbit at 8:37 a.m. EST on 15 December. The launch was carefully timed to enable Schirra and Stafford to enter an orbit whose plane closely paralleled that of Frank Borman and Jim Lovell … and enable suitable conditions for a rendezvous on their fourth circuit of Earth.

Glorious view of the Indian Ocean, captured by the astronauts of Gemini VI-A. Photo Credit: NASA

Six hours of work awaited them. At orbital insertion, they were trailing Gemini VII by almost 1,200 miles. An hour and a half after launch, Schirra pulsed his ship's thrusters to increase the apogee—the highest point of their orbit—to some 180 miles and close the distance to some 600 miles (960 km); this was followed at 10:55 a.m. by a "phase-adjustment" burn, whose purpose was twofold. Firstly, it reduced the distance between them and the target, and secondly, it raised the lower point of Gemini VI-A's orbit (its "perigee") to about 120 miles (190 km). Most importantly, it established the timing for the subsequent chase. Half an hour later, Schirra turned the spacecraft 90 degrees to the "right"—in a southward direction—and again fired the thrusters to push Gemini VI-A into the same plane as Borman and Lovell. By this point, three hours after launch and entering their third orbit, they had narrowed their distance still further to about 300 miles (480 km). At 11:52 a.m., Capcom Elliot See told them that they should soon be able to establish radar contact with Gemini VII … and shortly thereafter a flickering signal was replaced by a solid lock-on.

Stafford, meanwhile, busied himself with a circular slide rule and heavily crosshatched plotting chart on his lap, checking the computer's analysis of the radar data and relaying information to Mission Control. Shortly thereafter they placed their spacecraft in the "computer"—or automatic—rendezvous mode, and Schirra dimmed the interior lights to aid his visibility. At 1:41 p.m., he announced his first visual sighting of what he thought was a star: "My gosh, there is a real bright star out there. That must be Sirius."

It wasn't. It was Gemini VII, glinting in the sunlight just 60 miles (96 km) away. They lost sight of it briefly when it entered Earth's shadow, but when their eyes adjusted they identified its blue tracking lights. Twelve minutes later, when the target was 40 miles (64 km) ahead and the geometry was correct, Schirra initiated the terminal phase manoeuvre designed to close the range to about two miles. He then executed a pair of mid-course correction burns and, at 2:27 p.m., just a few thousand feet from their target, started pulsing Gemini VI-A's forward thrusters to steadily reduce the closure rate.

Closer and closer they drifted, until Schirra and Stafford were just 120 feet from Borman and Lovell, with no relative motion between them. Back on Earth, flight controllers erupted in applause and waved small American flags, while Chris Kraft, Bob Gilruth, and other senior NASA managers fired up celebratory cigars. Unlike the Soviet Vostok 3 and 4, which had merely drifted past each other at a distance of several miles as a result of being in slightly different orbits in August 1962, Wally Schirra and Tom Stafford had achieved a "real" rendezvous. "I don't think rendezvous is over until you are stopped," he wrote, "completely stopped, with no relative motion between the two vehicles, at a range of approximately 120 feet. That's rendezvous!"

Backdropped by the grandeur of Earth, Gemini VII drifts serenely in the inky darkness. Photo Credit: NASA

From their vantage point in the "passive" spacecraft, Borman and Lovell had expressed fascination at the thruster bursts and spurts emerging from Gemini VI-A. At one stage, they were startled to see a tongue-like jet some 30 feet (9 meters) long! The rendezvous cost Schirra barely 38 percent of his fuel and left him plenty in reserve to fly a tour of inspection of, and station-keep with, Gemini VII for the five hours and three orbits. At one stage, Schirra maneuvered as close as a foot (30.4 cm), allowing he and Stafford to hold up a "Beat Army" card in their window to torment Borman, a West Point graduate. In response, Borman held up a "Beat Navy" card. Gemini VI-A moved to the rear of its sister craft, then came nose-to-nose, and so stable were both Geminis that, for a time, neither Schirra or Borman had to touch his controls.

At length, the two spacecraft went their separate ways … but not before Schirra and Stafford took the opportunity for a prank. Borman and Lovell were initially alarmed to hear Stafford report that he saw "an object, looks like a satellite, going from north to south, probably in polar orbit … Looks like he might be going to re-enter soon. Stand by one. You just might let me try to pick up that thing." Then, over the communications circuit came the sound of the Gemini VI-A astronauts playing "Jingle Bells." The "object," it seemed, was the familiar, jolly, red-suited, white-bearded old man himself, making his annual "re-entry" to deliver his payload of presents to terrestrial children. …

In fact, Mickey Kapp, producer of Bill Dana's "José Jiménez in Orbit" album, had provided Schirra with a small, four-hole Hohner harmonica just days before launch. Schirra had secured it in one of the pockets of his space suit with dental floss. "I could play eight notes," he wrote, "enough for 'Jingle Bells.' It may not been a virtuoso performance, but it earned me a card in the musicians' union of Orlando." Not to be outdone, Francis Slaughter, of the Cape's Flight Crew Operations Office, had fitted small bells to the boots of Stafford's suit … supposedly as a joke, but little realizing they would provide backing rhythm for Schirra's Christmas soiree. Today, the tiny harmonica and Stafford's bells are enshrined in the Smithsonian.

Gemini VI-A splashed down safely on 16 December, followed by Gemini VII a couple of days later. Despite their discomfort, Borman and Lovell had suffered few ill-effects from two weeks in space, and Schirra and Stafford had demonstrated that rendezvous between two piloted vehicles could be practically achieved early in a mission. Although triumph and tragedy would both characterise NASA's path in space and on the ground over the next two years, the achievement of the two Geminis, just days before Christmas in 1965, had shown that the Moon was drawing ever closer and President Kennedy's goal of bootprints on its dusty surface was steadily turning from a hopeless dream into a reality.

 

Copyright © 2013 AmericaSpace - All Rights Reserved

 

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