A very difficult Centennial cachet cover is shown for the failure of the Gemini 6 Agena target vehicle that would have been the rocket target in orbit for the Gemini 6 crew of Wally Schirra and Tom Stafford with which to rendezvous in space, October 25, 1965. After successful launch, the agena seemed to "be wobbling" even as the rocket's attitude control system labored to keep it stable in flight. The rocket's small secondary engines ignited and the gas generator valve opened to fire the main engine to carry the agena into orbit. A telemetry signal in the Mission Control Center showed that the rocket engine had fired exactly on time. That, however, was the last good news received.
In Houston Mission Control, NASA engineers were astounded to learn there was a problem. U.S. Air Force radar was tracking what seemed to be five pieces of the target vehicle. The NASA tracking station in Carnarvon, Austalia, confirmed no telemetry was being received for the agena. It had exploded.
A dual cancelled Sokolsky cachet cover is pictured for the Gemini 6A scrub date of December 12, 1965, at Cape Canaveral, Florida.
On this launch date, ejection from their Gemini Titan 6A spacecraft by crewmembers Wally Schirra and Tom Stafford was required by flight regulations as their faltering Gemini Titan booster appeared to be failing after launch had actually been initiated. Astronaut Wally Schirra, however, thought the booster rocket had shut down and had not launched even though the spacecraft launch clock had started.
In one of the most serious moments of the Gemini Program, Schirra decides not to pull the spacecraft's D-ring that would eject the astronauts and their spacecraft away from the failing Gemini II rocket and precipitating failure of the GT 6A mission. Wally Schirra makes a tough call by not pulling the D-ring and saving his Gemini mission contrary to program spaceflight requirements.
Space Cover #249: Wally Schirra Doesn't Pull the D-Ring
Watching the day's events unfold after the October 25, 1965, mission scrub, Gemini 6 mission were three key officials from the McDonnell Company, the company that built the Gemini spacecraft: spacecraft chief Walter Burke; his deputy, John Yardley; and head of the company's launch team at the Cape, Ray Hill.
The three McDonnell managers put together an incredible plan to keep Project Gemini on schedule. They proposed using the Gemini 7 spacecraft, scheduled for a December 4 launch date on an extended 14-day mission, as the new rendezvous target for the Gemini 6 crew members, forgoing rendezvous with another agena target. For the plan to work, though, Gemini 6 would have to launch within two weeks after Gemini 7.
Incidentally it would have to launch from the same launch complex, LC 19, the Cape's only launch site equipped to handle Gemini rocket launches. The normal time between Gemini launches was two to three months, not two weeks. Preliminary discussions affirmed it would be practically impossible to pull a new plan together.
But Burke, Yardley, and Hill's idea was based on more than just a brainstorming, seat of the pants problem solving session. It was built on a fast-turnaround plan completed a few months earlier by the Martin Marietta Company, manufacturer of the Gemini Titan II booster rocket that powered both the Gemini 6 and Gemini 7 missions. The next day, Burke and Yardley flew to meet with Bob Gilruth, director of NASA's Manned Spacecraft Center. Gilruth was amazed and apprehensive about their planned idea but asked his technical directors to review it closely.
Gilruth's engineers were supportive but didn't see how it could be done. They continued discussion on it. After several hours, the managers agreed there might be a workable way to do this. They spent the following day adding the details of a prospective plan. The morning of October 28, 1965, NASA Administrator James Webb convened a press conference to announce that Gemini 7 and Gemini 6 would simultaneously participate in a rendezvous mission with a new plan. Webb called the new joint mission, the "Spirit of 76" in which the Gemini 7 spacecraft would become the target vehicle during its extended mission and Gemini 6 would become the rendezvous spacecraft.
That the entire series of events for the Gemini rendezvous plan using two spacecraft unfolded in just three days was a testament to the great trust NASA leadership had in several government contractor engineering teams supporting the Gemini Program. The reworked Gemini 6 space mission would be renamed Gemini 6A. The launch of the two Gemini spacecraft only a few days apart from one another using the same launch pad was now a top space program priority with President Lyndon Johnson's personal attention focused on the spaceflight after the failure of Gemini 6's agena target vehicle.
Gemini 6A's new launch attempt would be December 12, 1965, as the mission's countdown again was reset. The crew is now back on the launch pad on December 12th, Wally Schirra's hand was firmly on his spacecraft's "D-ring." After initial thundering of the Gemini rocket engines, suddenly things were not right. Schirra's attention was focused on launching, but things were very wrong. Schirra was ready to eject both himself and his crew mate, Tom Stafford in their spacecraft from what he thought was his failing Gemini Titan 6A rocket.
Schirra's emergency spaceflight procedures required him to pull the spacecraft's "D-ring" to eject both crew members from the Gemini Titan booster to save both astronauts from a holocaust of 150 tons of explosive rocket propellant detonating as the Gemini 6A rocket falters and crashes back onto the launch pad. The spacecraft's airborne programmer and elapsed time clock indicated the Gemini Titan has launched. However, Schirra didn't think Gemini 6A had moved in spite of the rocket's short, thundering, initial ignition; he felt the rocket had shut down and was still in its chocks. Gemini 6A had not gone anywhere. It was a heart stopping moment as Wally Schirra didn't pull the "D-ring."
Now three days later on December 15, 1965 as the new third countdown was completed, mission commander Wally Schirra coaxes Gemini 6A "...for the third time, go!" as the booster rocket thunders to life at launch complex 19, picks up speed, and blasts clear of the launch tower. Crew member Tom Stafford disbelievingly checks his flight computer but sees they are traveling at 7,830 meters per second and are now well on their way away from the Cape and speeding away into space.
Already in Earth orbit, the crew of Gemini 7, astronauts Frank Borman and Jim Lovell, await rendezvous by Gemini 6a's Schirra and Stafford. As the Gemini 7 crew orbits over the Cape, at the time of launch for Gemini 6A, they see only clouds at the time of launch. Several minutes later, orbiting over Tananarive, Malagasy Republic, Africa, the Gemini 7 crew briefly glimpse Gemini 6A now displaying its contrail and speeding to meet them in orbit.
Schirra and Stafford placed Gemini 6A in their computer for automatic rendezvous mode 3 hours 51 minutes into their flight. While Gemini 6A gained slowly on its target, Schirra dimmed the lights on his side of the spacecraft to improve outside visibility. At 5 hours 4 minutes into the flight, Schirra exclaimed, "My gosh, there is a real bright star out there. That must be Sirius." The bright "star" in fact was Gemini 7, reflecting the Sun's sunlight from 100 kilometers away as Gemini 6A steadily closed on Gemini 7, their target vehicle.
Schirra and Stafford catch Gemini 7 after 5 hours 16 minutes into their flight. Schirra prepared to make the last rendezvous maneuvers. The two spaceships were now close enough to allow Spacecraft 6A to thrust directly towards Spacecraft 7. Schirra fired his rocket thrusters and continued to close on Gemini 7 at a slower careful rate of approximately three kilometers every minute and a half. Schirra and Stafford briefly lose sight of Gemini 7 when they pass into Earth's darkness but soon after this they pick up Gemini 7's running lights.
In the terminal stage of rendezvous, the Gemini 6A crew saw the stars Castor and Pollux in the constellation Gemini aligned with their target spacecraft. Then the Gemini 7 spacecraft flashed into sunlight and became almost too bright to see. From a distance of 200 meters, the reflection from the spacecraft resembled a carbon arc search light. After a brief braking and translation maneuver, Gemini 6A slowed until the two vehicles were 40 meters apart with no relative motion between them. The World's first manned space rendezvous was now a fact for the history books.
In Mission Control in Houston, a cheering crowd of flight controllers, managers, and engineers waved small American flags, while NASA managers Chris Kraft and Bob Gilruth, beamed on the achievement being made. The exact time was recorded. It was 2:33 pm on December 15, 1965, and Gemini 6A had successfully rendezvoused with Gemini 7!
The rendezvous in space by the crews of Gemini 6A and Gemini 7 is quickly picked up as a major news item by the press and international news media and commands the World's attention around the World as the combined space rendezvous mission with two Gemini spacecraft crews achieved daring success in the face of difficult failures. This incredible achievement was indeed, the "Spirit of 76"!
A remarkable oversized combined mission cover is shown for the "Spirit of 76" with two rubber stamped cachets for the Gemini 6A mission and the Gemini 7 mission on the cover and signed by all four astronauts for the two spaceflights making the "Spirit of 76"revamped missions successful.
From top to bottom, the astronaut crew members signing the cover are Frank Borman and James Lovell of the Gemini 7 mission and Thomas Stafford and W. M. "Wally" Schirra of the Gemini 6A mission, on December 18, 1965, on board USS Wasp, CVS-18, the combined missions' primary recovery ship.
After an initial explosion and loss of Gemini 6's agena rocket scrubbing its first mission, a second mission scrub due to failure of the Gemini 6 booster rocket to launch and a razor thin scare to not eject the spacecraft and scrap this mission, and finally, successful rendezvous and mission success using Gemini 7 spacecraft as a target vehicle, the Gemini 6A crew of Wally Schirra and Tom Stafford, splashdown and are recovered by USS Wasp, the mission's primary recovery ship, December 18, 1965 and later USS Wasp also recovers the Gemini 7 crew of Frank Borman and Jim Lovell.
The remarkable turn of events by the four astronauts of Gemini 7 and Gemini 6A proved Gemini's "Spirit of 76" is successful and an amazing accomplishment of the Gemini Program!
Steve, SU 4379
posted 01-19-2014 06:15 PM
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