Gemini 9A

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Gemini IX-A
The Angry Alligator - GPN-2000-001354.jpg
Gemini IX-A rendezvous with the ATDA, discovering that the docking target's payload fairing has failed to separate
Operator NASA
COSPAR ID 1966-047A
SATCAT № 2191
Mission duration 3 days, 20 minutes, 50 seconds
Orbits completed 47
Spacecraft properties
Spacecraft Gemini SC9
Manufacturer McDonnell
Launch mass 3,800 kilograms (8,300 lb)
Crew
Crew size 2
Members Thomas P. Stafford
Eugene A. Cernan
EVAs 1
EVA duration 2 hours, 7 minutes
Start of mission
Launch date June 3, 1966, 13:39:33 (1966-06-03UTC13:39:33Z) UTC
Rocket Titan II GLV, s/n #62-12564
Launch site Cape Canaveral LC-19
End of mission
Landing date June 6, 1966, 14:00:23 (1966-06-06UTC14:00:24Z) UTC
Landing site 27°52′N 75°0.4′W / 27.867°N 75.0067°W / 27.867; -75.0067
Orbital parameters
Reference system Geocentric
Regime Low Earth
Perigee 158.7 kilometres (85.7 nmi)
Apogee 311.5 kilometres (168.2 nmi)
Inclination 28.91 degrees
Period 88.78 minutes
Epoch June 6, 1966[1]

Ge09Patch orig.png S66-15621.jpg
(L-R) Stafford, Cernan


Project Gemini
← Gemini 8 Gemini 10

Gemini 9A (officially Gemini IX-A)[2] was a 1966 manned spaceflight in NASA's Gemini program. It was the 7th manned Gemini flight, the 13th manned American flight and the 23rd spaceflight of all time (includes X-15 flights over 100 kilometres (62 mi)).

Crew[edit]

Original prime crew[edit]

The original prime crew of Gemini 9 - Elliot See and Charles Bassett
Position Astronaut
Command Pilot Elliot M. See, Jr.
Pilot Charles M. Bassett II
Crew died in plane crash four months before launch

On February 28, 1966, See and Bassett were flying from Texas to inspect the Gemini 9 spacecraft at the McDonnell Aircraft plant in St. Louis, Missouri. The conditions at Lambert Field were poor and, as a consequence, in attempting a visual approach and landing, See hit one of the assembly buildings of the factory and caused the aircraft to crash, killing himself and Bassett instantly. As a consequence, the backup crew was promoted to prime crew, the first time this had occurred since the flight of Mercury-Atlas 7 in 1962.

For more details on this topic, see 1966 NASA T-38 crash.

Original backup crew and new prime crew[edit]

Position Astronaut
Command Pilot Thomas P. Stafford
Second spaceflight
Pilot Eugene A. Cernan
First spaceflight
Originally backup crew
Assigned to fly after deaths of original prime crew

New backup crew[edit]

Position Astronaut
Command Pilot James A. Lovell, Jr
Pilot Edwin E. Aldrin, Jr.

The promotion of Stafford and Cernan from backup to prime crew meant that a new backup crew was required. Jim Lovell and Buzz Aldrin were originally the backup crew for Gemini 10. This is significant as the standard crew rotation meant that a spot on the backup crew of Gemini 10 would have placed Buzz Aldrin on the prime crew of the non-existent mission after Gemini 12 (the crew rotation usually meant that after serving on a backup crew, an astronaut could expect to skip two missions and then be on a prime crew). Being moved up to the backup crew of Gemini 9 meant that Aldrin flew as part of the prime crew on Gemini 12, which played a major part in his selection for the Apollo 8 backup and Apollo 11 prime crews, ultimately making him the second man on the Moon.

Mission parameters[edit]

Gemini 9 original prime crew (front row, L-R) Elliott See, Charles Bassett;
and backup crew (back row, L-R) Tom Stafford, Gene Cernan

First rendezvous[edit]

  • June 3, 1966 - 17:45 - 18:00 UTC

Spacewalk[edit]

  • Cernan
    • Start: June 5, 1966, 15:02:00 UTC
    • End: June 5, 1966, 17:09:00 UTC
    • Duration: 2 hours and 7 minutes

Objectives[edit]

Gemini 9A launch from LC-19

One of the mission objectives was to dock with an Agena Target Vehicle in the same manner as the Gemini 8 mission. However, during the launch of the Gemini 9 Agena on May 17, 1966, its Atlas booster malfunctioned (rather than the Agena itself, as had previously caused Gemini 6 to be recast as Gemini 6A), and it failed to make it to orbit.[3] As a result, the Gemini 9 launch scheduled for later that morning was scrubbed.

On June 1, 1966 a substitute for the Agena was launched in the form of the ATDA (Augmented Target Docking Adapter), designed and built by McDonnell (the manufacturers of the Gemini spacecraft). The ATDA was made from the forward docking section of an Agena with the reentry control section of a Gemini. It was built using already tested equipment and launched using the Atlas-SLV3 rocket. The docking was canceled, though, after Stafford and Cernan rendezvoused with the target to find its payload fairing still attached over the docking port, which made it look, in Stafford's words, like an "angry alligator."

The ATDA is launched from Cape Kennedy's Pad 14 atop an Atlas launch vehicle at 10 a.m., June 1, 1966.

As well as the docking there was also a planned EVA by Cernan. The plan was for him to move to the rear of the spacecraft and strap himself into the Air Force's Astronaut Maneuvering Unit (AMU). This was the first 'rocket pack' and a predecessor of the Manned Maneuvering Unit used by Shuttle astronauts in the 1980s. It had its own propulsion, stabilization system, oxygen and telemetry for the biomedical data and systems. It used hydrogen peroxide for propellant, and because it produced extremely hot gases, Cernan's spacesuit was modified with "pants" made of woven steel known as "Chromel-R," which was later used on the gloves and Moon walking boots on Apollo spacesuits. This material was developed by the Air Force Systems Command for use in high-temperature deceleration devices for aerospace systems.[4] (The current MMU uses nitrogen gas, which remains cold when vented.)

As well as the rendezvous and EVA, the other major objective of the mission was to carry out seven experiments. The only medical experiment was M-5, which measured the astronauts reactions to stress by measuring the intake and output of fluids before, during and after the flight.

Flight[edit]

Launch attempts[edit]

Gemini 9 Target Vehicles
Agena GATV-5004
Mass 3,252 kilograms (7,169 lb)
Launch site LC-14
Launch date May 17, 1966
Launch time 15:12 UTC
Destroyed 15:19 UTC
ATDA #02186
NSSDC ID: 1966-046A
Mass 794 kilograms (1,750 lb)
Launch site LC-14
Launch date June 1, 1966
Launch time 15:00:02 UTC
1st perigee 298.4 kilometres (185.4 mi)
1st apogee 309.7 kilometres (192.4 mi)
Period 90.5 min
Inclination 28.87
Reentered June 11, 1966

The first launch attempt of Gemini 9A was on June 1, 1966. The ATDA had launched perfectly into a 298 kilometers (185 mi) orbit, though telemetry from it indicated that the launch shroud had failed to open properly. However, the Gemini spacecraft was not able to launch the same day as planned. At T-3 minutes, the ground computers could not contact the Gemini computers for some reason and the 40 second launch window opened and closed without the launch. This earned Tom Stafford the title of "Mayor of Pad 19."

The second launch attempt went perfectly with the spacecraft entering into orbit. With this launch, Stafford could say that he had been strapped into a spacecraft six times ready for launch.

Rendezvous[edit]

Tom Stafford inside the Gemini spacecraft

Stafford made the first thruster burn 49 minutes after launch, to add 22.7 meters per second (74 ft/s) to their speed, raising their perigee from 160 to 232 kilometers (86 to 125 nmi). An hour and 35 minutes later, Stafford corrected phase, height, and out-of-plane errors by pointing the spacecraft 40° down, and 3° to the left. Fifty-one seconds later, he fired the thrusters again to add 16.2 meters per second (53 ft/s) to their speed and put them into a 274-by-276-kilometer (148 by 149 nmi) orbit, closing at 38 meters per second (120 ft/s) on the ATDA.

The first radar contact with the target registered a distance of 240 kilometers (150 mi) away and they had a solid lock at 222 kilometers (138 mi). Their first visual sighting came 3 hours and 20 minutes into the mission, when they were 93 kilometers (58 mi) away. They noted that they could see the flashing strobe lights on the ATDA, designed to aid identification from a distance. This made them hope that the launch shroud had in fact been jettisoned and that the telemetry was wrong.

As they got closer, they found the ATDA to be in a slow rotation, with the conical nose shroud still attached, the two pieces hanging agape at the front like a giant, open jaw. Stafford described "It looks like an angry alligator out here rotating around". He asked if maybe he could use the spacecraft to open the 'jaws' but the ground decided against it, fearing this might cause damage to the spacecraft.

ATDA, with its payload fairing still attached, as seen from Gemini 9

The crew described how the shroud's explosive bolts had fired, but two neatly taped lanyards were holding the shroud together. In Mission Control, backup pilot Buzz Aldrin suggested that Cernan cut the spring-loaded lanyards with surgical scissors from the equipment pack. An experiment on the ground demonstrated this could indeed slice the lanyards, but also showed the ATDA bristled with dangerous, sharp edges. Ground controllers were, in Deke Slayton's words, "just aghast" at the idea, which did not take into consideration the substantial risks of the explosive bolts holding the lanyards together, the constant spinning of the ATDA, or the fact that the lanyards, under tension from the springs, might snap apart, whip back, and puncture Cernan's spacesuit.[5]

The reason for the lanyards' condition was soon discovered: Douglas built the shroud to be attached to the Agena second stage but the Air Force decided at the last minute that Atlas could achieve the desired orbit without NASA's second stage. This dropped NASA out of the launch and meant that the ATDA and fairing would be installed directly on Atlas—not Agena—and by a McDonnell crew instead of the normal Lockheed crew.

NASA had contracted the Douglas engineer to witness, inspect and sign off on the fairing installation on the Agena second stage, but because Agena would not be used, McDonnell personnel would now install the fairing with which they were unfamiliar and they refused to permit the Douglas engineer on the gantry—over the protests of the engineer and NASA personnel, saying that it was a simple structure and they did not need any help. On launch day, the McDonnell crew followed procedures published by Lockheed, which had been copied from Douglas documents. The instructions said, "See blueprint," but the Lockheed drawing was not used. The Douglas technician who normally hooked up the lanyards knew what to do with the loose ends, even without the blueprint. But he was not permitted on the gantry, and the strangers fixing the ATDA's shroud looked at the dangling straps, wondered what to do with them, and taped them under the small fairings that protected the explosive bolts.[6] After the launch, the Douglas engineer, with the help of Lockheed, set up a backup fairing and demonstrated the problem to McDonnell personnel and to George Mueller, NASA's Office of Manned Space Flight administrator.

The crew then did some planned rendezvous practice that involved them moving away from the ATDA by firing their thrusters and then practicing approaching from below the target. They then got some much needed food and rest.

On the second day of the mission, they again approached the ATDA, this time from above. Once they were stationkeeping alongside, they were given permission for their EVA. But they were tired and Stafford did not want to waste fuel keeping himself near the ATDA during the EVA when there was little they could do with it. It was decided to postpone the EVA until the third day.

EVA[edit]

Astronaut Eugene Cernan during EVA

On the third day, Cernan began the EVA, which proved to be troubled from the start. After pumping up his pressure suit to three and one half pounds of pressure per square inch, "the suit took on a life of its own and became so stiff that it didn't want to bend at all." He struggled to move inside his stiff suit.[7]" As soon as he left the spacecraft, he began tumbling uncontrollably, which was not helped by his umbilical which moved wildly and gave Cernan difficultly in controlling his movements.[8] He eventually made it back to the hatch area and began the slow climb to the rear of the spacecraft where his AMU was stored. While he was disconnecting himself from his capsule and hooking up to the backpack, his heart rate rose to about 155 beats per minute. His spacesuit had "all the flexibility of a rusty suit of armor".[9]", which made everything take much longer than expected. The lack of hand and foot holds also made him unable to gain any leverage, which made it hard to turn valves or even to perform any basic movements. While making the connections, Cernan became very tired. During this portion of the EVA, his pulse soared to about 180 beats per minute; the flight surgeon on the ground feared he would lose consciousness. As he sweated, his visor began to fog. He rubbed his nose against the visor the clear a hole so he could see.[10]" After making all the necessary connections, Cernan rested for a few minutes while Mission Control decided whether or not to proceed with the planned test of the AMU.

At this point Cernan decided that there was considerable risk in continuing the EVA. He had poor visibility from within his spacesuit and had found that he could not move very well. He would have to disconnect himself from the umbilical that attached him to the Gemini (though would still be attached by a longer thinner lead), after he had connected himself to the AMU. But when he had finished with the AMU he would somehow have to remove it with one hand, while the other held onto the spacecraft. Cernan, while physically exhausted wanted to proceed, but Stafford called an end to the proceedings and ordered Cernan back inside before getting a chance to fly the AMU[11]". He managed to move himself back to the cockpit and Stafford held onto his legs to give him a rest and assist Cernan in getting back into the spacecraft. After trying to remove a mirror mounted to the side of the spacecraft, his suit cooling system overheated and his face plate fogged up completely, denying him any vision. Cernan also felt excruciating pain as he moved back into his seat, as his suit was still fully pressurized and he had to move down far enough inside the spacecraft for the hatch to close.[8] He and Stafford managed to get the hatch closed and the cabin repressurized. Cernan had spent 128 minutes outside the spacecraft.

The Gemini spacesuit was cooled by air. When an astronaut had an increased work load he began to sweat and in the confined space of a suit the cooling system would become overwhelmed and the visor would fog. The astronaut would then be effectively blind because he had no way of wiping off the faceplate. In future Gemini EVAs, the work loads of the astronauts were reduced, but it was clear that during lunar exploration, workloads could be significant and changes were made to ensure that the Apollo EVA suit would be water cooled. This was accomplished by having the astronaut wear a garment that contained many thin tubes that circulated water near the skin. It was very effective and there were very few cases where astronauts used the "High" Cooling selection even though they were working hard and on the Moon in a 100 °C sun.

The AMU was not finally tested in space until a modified version called the Manned Maneuvering Unit (MMU) was flown by astronaut Bruce McCandless on Space Shuttle mission STS-41-B in February 1984. As a result of Cernan's experience, the AMU never again flew on Gemini, as it was not essential to developing technology for the Apollo Moon landing mission.

Stafford has said in a 2001 interview that there was a real concern that Cernan would not be able to get back into the capsule.[citation needed] As it would not have been acceptable for Stafford to cut Cernan loose in orbit he stated that the plan was to make re-entry with the astronaut still attached by his umbilical. However, such an action would have resulted in the deaths of both men.

Experiments[edit]

There were two photography experiments. S-1 hoped to image the Zodiacal light during an EVA, but this was changed to inside the spacecraft after the problems encountered by Cernan. And S-11 involved the astronauts trying to image the Earth's airglow in the atomic oxygen and sodium light spectra. They took 44 pictures as part of this experiment with three being of actual airglow.

S-10 had hoped to retrieve a Micrometeorite Collector from the ATDA, though this failed after they were unable to dock with it. They were able to image it though during their close approaches. Instead they were able to recover the collector from the Gemini spacecraft (S-12). D-12 also failed as it was an investigation of controlling the AMU.

The last experiment was D-14 which was UHF/VHF Polarization. This was an extendable antenna mounted on the adapter section at the rear of the spacecraft. It was hoped to obtain information about communication through the ionosphere. Six trials of this were performed but the antenna was broken by Cernan during his EVA.

Reentry[edit]

Gemini 9 splashes down at 9:00 A.M., June 6, 1966.

The day of the EVA was also their last in space. On their 45th revolution of the Earth, the crewmen fired the retrofire rockets that slowed them down so that they would reenter. This time the computer worked perfectly, meaning they landed only 700 meters from the planned landing site and were close enough to see the prime recovery ship, USS Wasp. The splashdown happened closer to the recovery ship than any other manned spacecraft.[citation needed]

After the mission it was decided to set up a Mission Review committee to make sure that the objectives planned for each mission were realistic and that they had a direct benefit for Apollo.

The Gemini 9A mission was supported by the following U.S. Department of Defense resources: 11,301 personnel, 92 aircraft and 15 ships.

Insignia[edit]

The Gemini 9 patch is in the shape of a shield and shows the Gemini spacecraft docked to the Agena. There is a spacewalking astronaut, with his tether forming the shape of a number 9. Although the Gemini 9 mission was changed so that it docked with the ATDA, the patch was not changed. It is also not known whether Bassett and See had designed a patch for the mission as the original crew.

Spacecraft location[edit]

The spacecraft is on display at the Kennedy Space Center Visitor Center, Florida.

See also[edit]

References[edit]

 This article incorporates public domain material from websites or documents of the National Aeronautics and Space Administration.

  1. ^ McDowell, Jonathan. "SATCAT". Jonathan's Space Pages. Retrieved March 24, 2014. 
  2. ^ Hacker, Barton C.; Grimwood, James M. (September 1974). "Chapter 11 Pillars of Confidence". On the Shoulders of Titans: A History of Project Gemini. NASA History Series. SP-4203. NASA. p. 239.  With Gemini IV, NASA changed to Roman numerals for Gemini mission designations.
  3. ^ "Gemini 9 wives very downcast". The Windsor Star (Windsor, ON). United Press International. May 17, 1966. p. 1. 
  4. ^ "The AFSC Laboratories". USAF. 
  5. ^ "Last Man on the Moon" Eugene Cernan and Dan Davis, P.123
  6. ^ "On The Shoulders of Titans - Chap. 14". Archived from the original on 2010-03-11. Retrieved 2011-10-30. 
  7. ^ "Last Man on the Moon" Eugene Cernan and Dan Davis, P.131
  8. ^ a b Cernan, Eugene; Davis, Donald A. (2013). "13". The Last Man on the Moon: Astronaut Eugene Cernan and America's Race in Space (Kindle) (Unabridged. ed.). New York: St. Martin's Press. ISBN 9781429971782. 
  9. ^ "Last Man on the Moon" Eugene Cernan and Dan Davis, P.134
  10. ^ "Last Man on the Moon" Eugene Cernan and Dan Davis, P.137
  11. ^ "Last Man on the Moon" Eugene Cernan and Dan Davis, P.140

External links[edit]