Issue 60

Editor’s Note: If you missed part 1 you can find it HERE. If you’re interested in a couple of relevant videos please check out: https://youtu.be/_cHm7bJolnE (29 seconds) & https://youtu.be/ZHO_Xi4N_Mg (2.5 minutes)

Let’s pick it up from 29 Oct 1965. NASA Flight Control in Houston TX was in high gear. Gene Kranz, the Gemini Flight Director summed it up with this statement: “It was like watching Patton’s Third Army break off their offensive, perform a pivotal maneuver, turn, and march 100 miles in the dead of winter to relieve Bastogne.” The pivot from ‘wait until spring 1966 to attempt a Gemini-Agena docking mission’ to what would be a dual Gemini RPO mission was underway and at full throttle.

On 29 Oct, the Titan II that would be used to launch Gemini VII was brought to LC 19 to replace its slighter weaker brother that was slated for Gemini VI. At Goddard in Maryland, work was commencing on the reconfiguration of the tracking network that would allow two simultaneous Gemini missions. In Houston, crew training for Gemini VII’s extended flight, and Gemini VI’s rendezvous attempt, was in full swing. It was a busy time leading up to 4 Dec 1965 when Gemini VII’s launch went off flawlessly and Frank Borman and Jim Lovell began their 14-day marathon. Imagine sitting in a Volkswagen bug front seat for 14 days, weightless of course. Fortunately, these two astronauts were close and compatible good friends. They were in a nice circular orbit and that would be what Gemini VI wished for in their mission that would launch 9 days later. But first at the Cape there was a task to fix up the launch pad after Gemini VII launch and get Gemini VI out there and ready to go. No sooner had Lovell and Borman flown over the Atlantic, repairman and welders raced to the pad to begin cleanup and take care of any damage that had taken place. Fortunately, the damage was minimal. Instrumentation was replaced. In one day, Gemini VI’s Titan II booster was erected, the spacecraft mated, and all testing and documentation completed. The normal 1-2 months of preparation was accelerated to 8 days. The launch team was ready for Gemini VI’s launch on 12 Dec.

Sunday morning at 0954 EST the main engines of Gemini VI roared to life. The roar turned into a sputter and the malfunction detection system began shutting down the engines. Whoa, this was a pucker factor event. 1.2 seconds after engine start, an electrical tail plug erroneously fell from the bottom of the booster. The purpose of this plug was to initiate the mission timer in the spacecraft to notify the crew the rocket had lifted off. Thus, inside the Gemini VI spacecraft, there were indications that the rocket had begun its upward climb. The “clock” was running, but the seat of the pants indicated they were not going anywhere. Here’s what the Flight rules said, pull the D-ring (ejection handle), and await a 20G ride on the ejection seats. Not a very popular option with the astronauts. But astronaut Schirra relied on a very sophisticated decision-making tool known as his “the seat of his pants” to realize the rocket was going nowhere. He remained cool and calm by the lack of acceleration. The pad crew quickly safed the system and the astronauts, for the second time, exited their capsule. There were now only six days left in Gemini VII’s flight. A typical turnaround after such a hang fire would take four days. That of course assuming the problem that caused the shutdown in the first place had been determined and fixed. By nighttime, the engine maker had discovered that the engine had shut down before the tail plug had come loose from its connector. Obviously, the tail plug had been shaken loose by the vibration of the engine start, but the fact that it had fallen out was not a cause of the preemptive shutdown.

Aerojet began a frantic search at the pad for the root cause of the failure. By morning the next day people were tired and knew little more than the night before. Then came the moment of discovery: backtracking through the engine’s history Aerojet engineers determined that a small, thimble-size cap-type cover had been placed on the gas generator port prior to removing the generator for cleaning at the Martin factory in Baltimore. The cover had never been removed once the cleaning was done! Quickly personnel verified that, indeed, there was a cover at the oxidizer inlet port. The cover was removed, the generator cleaned and checked out, and the engine reassembled that day later. Back to GO!

On 15 Dec 1965 a great deal was riding on the success of this plan-a plan that was hatched only two months ago. Many had said it was an utterly ridiculous idea, including some of those who had since come on board to lead a risky, fast paced strategy to orbit Gemini VI and test the technique of rendezvous and proximity operations for the first time. National security and prestige were on the line, and so too were a few reputations. Schirra and Stafford climbed into Gemini VI for their third launch attempt. At 0837 the engines of the Titan II roared to life. Five seconds later, the engines were still operating, and Schirra reported from the cockpit “Oh, the clock has started. It’s a real one!” Gemini VI was on its way. Third time was a charm! Just less than eleven days after its sister ship had left the same pad, Schirra and Stafford were on their way to execute a first-ever RPO in space. At Titan II upper stage cut off, Stafford checked his on-board computer and saw 7,830 meters per second; they were in orbit and the Gemini VI was on her way to join Gemini VII.

Let’s relive the Gemini VI chase. The rendezvous profile Gemini VI would fly was dubbed “M=4” (M equals four) and involved four orbits or six hours of maneuvering to catch up to Gemini VII. Just past the half way mark, Gemini VI’s radar lock signal flickered on as it locked onto Gemini VII. At five hours, five minutes into the chase, a bright star appeared in the cockpit window. Stafford made the report over to his commander Schirra, “Hey I think I got it. That’s Gemini 7!” Although Schirra first thought it was a star, it was indeed Borman and Lovell’s spaceship twinkling from the Sun’s illumination. The tempo of mid-course corrections picked up and soon an orbital dance commenced.

Following braking and tweaking, and appropriately bringing down the range rate as the range to Gemini VII closed, Schirra and Stafford brought their spacecraft to within 40 meters and zeroed

out the relative motion between the two craft. For three orbits, Gemini VI worked with the passive Gemini VII “target.” The two-spacecraft stayed within 90 meters of each other and got as close as 30 centimeters-close enough to communicate using hand written signs. For example, the Gemini VI crew were both Annapolis graduates and on board the Gemini VII was Borman a West Pointer. Well, the big game, Army-Navy, was soon to be played and the Gemini VI crew held up a sign “Beat Army.” Borman was not impressed. Get back to work! Schirra and Stafford each took turns at the controls. Docking

type approaches were flown and confidence soared as the four astronauts went through their paces. At one point Gemini VI “parked” 12 meters from Gemini VII and for 20 minutes stayed put in

type approaches were flown and confidence soared as the four astronauts went through their paces. At one point Gemini VI “parked” 12m from Gemini VII and for 20 minutes stayed put in a stable and hands off manner. A 90m circumnavigation maneuver to fly

around Gemini VII was accomplished. Believing the 90m goal not being representative of real station keeping, Schirra and Stafford repeated the fly around at 30m range. All the astrodynamics education Wally speaks of in his book paid off. It was not that RPO was easy, it was that they understood the dynamics and were very patient in applying thrust as they skirted about Gemini VII. As Gemini VII was about to begin its 12th day on orbit, Gemini VI bid the crew of Gemini VII

What was it that allowed the rapid decision making and light-speed execution witnessed in the era? First, we believe all of the decisions of the period, especially those that have been recounted here, were firmly grounded in the context of well-focused objective. As former NASA administratorMike Griffin recently pointed out to us, Kennedy’s speech before Congress was the quintessential directive for achieving a goal. “Man, Moon, Decade” The vision contained all that was needed to

provide a desired end state within a specified time. In the case of rendezvous, it was a noble accomplishment to target, but it was most important because it was a means to a more ambitious (and clearly defined) end. Certainly, the machines of Gemini 76 enabled the rapid turn in the final months of 1965. The Titan II was an ICBM by design, and responded as an ICBM in action. Gemini designer James Chamberlain’s vision of Gemini as a modular, simple, easily tested spacecraft paid dividends. But when we talked to some of the main actors involved about the success of Gemini 76, they focused on people and process. Gene Kranz, a Gemini flight director (who would later take over for

Chris Kraft) keyed on the personnel in “… ops and admin being the same, just changing hats.” In other words, those responsible for flight operations were also the managers/leaders/engineers. As operators, they understood from a technical and operational basis the risk and opportunities of their decisions. As managers, they were enabled to make decisions with little bureaucracy. The man in charge of all flight directors, Chris Kraft, answered the go/no-go decision for Gemini 76 for the operations crew: he was only three men removed in the management chain from the president of the US. Plus no one had to build any PowerPoint slides back then…humor!

We asked Captain Jim Lovell, USN ret, of Gemini VII and Lt Gen Tom Stafford of Gemini VI about the secrets to success of the mission recently. Lovell stated, “I don’t think technology had much to do with this-it was the management.…” Stafford responded, “We didn’t need a cast of thousands, or countless reviews, or rooms full of people, we had the goal and a can-do attitude accompanied with the will to succeed.”

Well, I’ll bring this space history lesson in for a landing. What can we learn from the first-ever RPO accomplished in space? The journey in 1965 was one of stumbling and setbacks, but on 15 December 1965 Gemini VI caught up to and danced with Gemini VII and thus with have the first ever RPO and an amazing Gemini 76 story of how we got to that day. They hurdled the unknown and found that while armed with astro knowledge and GRIT, this RPO stuff was doable. In his book “The Unbroken Chain,” Guenter Wendt, the launch pad boss (recall the Apollo 13 line by Tom Hanks “I vonder vhere Guenter vent?”) sums up the Gemini 76 mission saying “a new high point had been established in our trails for our assault on the Moon. To me, this was the crown jewel of the Gemini entire program.”

Gemini 8 would go on to accomplish the first ever docking in preparation for Apollo. In fact, the Gemini 8 mission would take a turn towards danger after it completed the rendezvous and docking. A stuck thruster put Armstrong and Scott into an accelerating tumble and Neil had to wrestle back control. With that, Neil Armstrong would solidify his place in line as the man to first set foot on the Moon. I hope on 15 Dec you’ll take time to celebrate the Gemini 76 accomplishment that was 57 years ago in 1965!