by Jay Chladek
In the command module, gamma-ray detectors were carried to study the effects of cosmic rays. This was similar to an experiment carried on Apollo 17. Cosmic rays, especially heavy high-energy ones (HZE particles), are filtered out by Earth’s atmosphere. But in space, they can be detected easily, as there is nothing to stop them until they hit something. NASA scientists in life science fields had also taken an interest in the possibly destructive effects of cosmic rays on living cells. Starting with Apollo 8’s flight, astronauts had mentioned that when their eyes were closed, they could occasionally see a bright flash, likely associated with a cosmic ray penetrating the vicinity of their optic nerves. The ASTP astronauts were asked to write down any experiences they had when noticing a similar flashing-light phenomenon. This data would be compared with readings from the radiation detectors to see if there was indeed a correlation.
From West Germany, the Apollo CSM carried an experiment called Biostack III. It was a container that carried various types of dormant living cells, from microbe spores to insect and shrimp eggs to plant seeds. Radiation detectors were located adjacent to the cell samples. The cells would be analyzed when the mission was over by allowing them to grow and develop in order to determine the effects of cosmic rays on living tissue. Earlier Biostack experiments had been flown on Apollo missions to the moon.
A joint Soviet-American experiment would obtain similar data on active fungus cultures in orbit to see how cosmic rays and zero gravity would affect them. Some fertilized killifish eggs would also be flown and hatched in sealed water bags to see how the fish developed in zero-g conditions. The combined ASTP crews would also be experiment subjects as well. Given that both groups of space travelers lived in different parts of the world, blood and tissue samples were taken before and after the flights to see what type of microbes (if any) they exchanged with one another in Earth orbit. Studies were made of the ASTP crews’ immune systems as well.
ASTP also flew some biological and materials-processing experiments in the docking module. Studies were carried out using a process called electrophoresis with special equipment developed by West Germany. In electrophoresis, an electric charge is used to separate either different biological cells or different molecular compounds from one another in a gel medium thanks to differences in their electrical properties. The process can be used to extract pure compounds or biological cells of a certain type or for removing impurities from a sample. It was hoped that performing this experiment in zero gravity would produce better results than on the ground, where gravity can alter the samples, potentially making them not as pure. ASTP was the first time an electrophoresis experiment would fly in orbit, but it wouldn’t be the last, as several shuttle missions conducted similar experiments over the next decade to study practical applications of this technology.
An electric furnace was also carried in the docking module, and this was used to conduct several experiments in materials science. The principle behind using a furnace is that materials that don’t normally combine in space under heat might be able to do so in a zero-g environment without gravity causing the heavier material to separate during cooling. The problem can be illustrated easily with a common oil-and-vinegar salad dressing. Shake the bottle, and the two materials mix together. But let the bottle sit, and eventually the heavier oil separates to the bottom while the lighter-weight vinegar settles on top.
Taking Shape
On both sides, there were some concerns about crew safety. For the most part, these concerns stemmed from the unfamiliarity each team had with equipment from the other country. The Americans and Soviets had differences in how they certified hardware and spacecraft for flight. For the most part, each side received assurances that the proven hardware flown before would do the job. But engineers made sure that there were no potential issues, just in case. For ASTP’s new equipment, the Soviets adopted a strategy similar to what NASA expected from a contractor in order to certify flight hardware for use. As designs were finalized and hardware developed, a safety review panel would check to see if any potential problems might crop up with the equipment. This kept things progressing along a positive path.
Soyuz 16 lifted off in December 1974 with ASTP backup cosmonauts Filipchenko and Rukavishnikov on board. It was a full dress rehearsal and test of the ASTP-configured Soyuz craft, with the new docking system attached to a docking collar acting as a stand-in for the American docking module. Soyuz 16 also included the internal-communications and radar equipment intended for use in ASTP. Deployment and retraction of the docking collar was tested in orbit, and tests were made with the communications systems on the frequencies that would be used for the ASTP mission itself. The crew also successfully tested lowering the internal cabin pressure with the atmosphere at 40 percent oxygen and 60 percent nitrogen for an extended period. Finally, the attached docking collar was jettisoned to test that explosive bolts could be used to separate the two spacecraft in an emergency. Soyuz 16 successfully returned to Earth after almost six days in orbit, which was the planned duration for the Soyuz half of ASTP.
With the return of Soyuz 16, that left two Soyuz missions to fly before Soyuz 19 flew the Soviet half of ASTP. Preparations were going well until Soyuz 18A experienced a launch abort that resulted in cosmonauts Vasili Lazarev and Oleg Makarov landing in the mountains of central Russia after a very short flight.
Under normal circumstances, the Soviets likely would have kept the mishap secret. But with the launch of Soyuz 19 scheduled for only three months later, the Soviets took an unprecedented step and told the Americans what had happened during the “April 5th anomaly.” The R-7 booster being used for this mission was part of an older series than the one planned for use in ASTP. While the fault was still being investigated, the newer booster already had one modification made to the electrical circuit controlling the locks between the core and third stages. If a similar failure occurred with only half the locks firing, they would be staggered around the ring instead of only on one side. So if the thrust of the third stage was needed to separate the two stages, it should have done so cleanly. NASA was satisfied with the explanation, and preparations continued with no further delays.
In Congress the launch abort plus lingering concerns about Soviet safety didn’t sit well with some. Or rather, it could be said that the situation gave some senators an excuse to give the ASTP program further scrutiny for political purposes. Among them was Senator William Proxmire from Wisconsin. The year that ASTP flew was the first year of Proxmire’s Golden Fleece Awards, which he would use as opportunities to showcase what he felt was pork barrel spending for dubious scientific studies. Yet even before that, Proxmire was a very vocal critic of NASA on Capitol Hill, and he received the ire of science and space program advocates everywhere. To many, it appeared he only criticized both NASA and the military to further his own career rather than to discourage improper spending practices. It seemed a bit strange to many people that Senator Proxmire was speaking in favor of canceling ASTP due to concerns for astronaut safety after the recent launch abort. NASA representatives spent portions of their regular briefings to Congress after Soyuz 18A to allay these safety concerns.
Tom Stafford explained the Senator Proxmire situation from his perspective in a NASA oral-history interview he conducted in 1976: “Proxmire tried everything he could to shoot the mission down. Not that he was against the Russians so much as that he was always against the space program and technology. Anything in technology, whether it was Air Force, NASA, he was against it. And I’ll tell that to his face. He likes to grab any issue, just so he can get a headline. That was the first time he was concerned about safety. Well, why wasn’t he concerned about all the other times?” Concerning the question of safety in relation to the April 5th anomaly, Stafford continues, “Well, that wouldn’t have had any effect on [Apollo] if they had aborted. That wouldn’t have affected our safety a damn bit.”
Launch Day
Ultimately, preparations came down to the final launch day for both the Ameri
cans and the Soviets. Public relations and television were a big aspect of ASTP. Most everything was negotiated in advance to prevent any last-minute substitutions or violations of protocol. To an observer, ASTP’s joint operations between the Americans and the Soviets looked like a meeting between two heads of state in space.
In public, the behind-the-scenes technical aspects of the flight would be largely ignored, and in their place would be a carefully orchestrated set of procedures for what would be done and when it would be done. Such procedures covered when the handshake would take place in orbit, who would do it, what materials would be exchanged, and which crewmembers would visit which spacecraft and when they would do so. A lot of these procedures had to be practiced in the joint training sessions, alongside the equipment familiarization. But the crews got through it, the same as any other training before a mission.
The Soviets would launch their half of the mission first, with Soyuz 19 as the primary vehicle. The backup spacecraft with the backup crew would be sitting on another launchpad, ready to go at a moment’s notice, should there be an unforeseen problem or an abort. About eight hours later, the Apollo spacecraft would lift off to begin its chase of the Soyuz for eventual rendezvous and docking. To help with communications in orbit when the craft might be out of range of ground-based tracking stations, the mission would use Applications Technology Satellite 6 (ATS-6) to relay transmissions using the Apollo’s high-gain antenna array fitted for lunar flights. This would allow for continuous coverage of the mission during nearly half of each ninety-minute orbit.
For Leonov and Kubasov, the big day came on 15 July 1975. The launch coverage was extensive as the cosmonauts were seen suiting up, riding their bus to the pad, and climbing the first set of stairs on the gantry before heading up the elevator that would take them to the spacecraft level to be strapped in. The countdown proceeded normally, and launch occurred on schedule at 12:20 GMT (08:20 EDT). The backup spacecraft did not have to be used, and Soyuz 19 entered orbit without any problems. All that was needed now was an Apollo spacecraft.
Stafford, Slayton, and Brand were asleep when the Soyuz lifted off, but when they awoke two hours later, they were informed that everything was proceeding well. It turned out to be a beautiful day with clear blue skies on 15 July. Since this would be the last flight of an Apollo spacecraft, a crowd of thousands flocked to the Space Coast to witness history in the making. KSC also got its share of international visitors, as Soviet ambassador to the United States, Anatoly Dobrynin, was on hand to watch from the Launch Control Center. Earlier that day, he watched the launch of Soyuz 19 in Washington DC at an auditorium with U.S. president Gerald Ford before flying to Florida.
For this mission, NASA set up a television camera inside the command module to transmit live pictures of the astronauts during their ascent. Countdown proceeded as normal, with no hang-ups. At 19:50 GMT (15:50 EDT) the eight engines of the Saturn 1B’s first stage ignited, and the Apollo lifted off the milk stool of pad 39B for a smooth climb into Earth orbit with a smoke trail that was visible for quite a distance. About ten minutes later, the spacecraft was in orbit and working perfectly.
And so began the two-day chase as Apollo gradually closed the distance with the Soyuz. Visual contact was made on 17 July 1975. As the spacecraft grew closer, they spent some time station keeping with one another. The rendezvous was successful, so that just left the docking. Finally, mission control had a message for both crews: “Houston is go for docking. Moscow is go for docking.” The two craft achieved a good dock, with Leonov saying, “We have capture,” and Stafford replying in Russian, “We also have capture.” Finally, Leonov said in English, “Apollo and Soyuz are shaking hands now.”
28. Photos of the ASTP spacecraft taken from each other are combined to show how the rendezvous and docking may have looked from outside. Courtesy NASA, composite by the author.
A few hours later, Stafford and Slayton opened the docking module’s hatch to the Soyuz. After a little delay, the handshake was made, and so began the joint activities between two spacecraft over a two-day period. After the pomp and ceremony of certificate signings and phone calls from state leaders, a meal between the cosmonauts and the astronauts took place. Somebody on the ground with a sense of humor had decided to decorate the Soviet toothpaste-style food tubes containing borscht with brand-name vodka labels. Later, during a press conference on orbit, Leonov was asked about the food. His reply was, “The best part of [a] good dinner is not what you eat, but with whom you eat.”
On the second day, Valery Kubasov hosted Vance Brand in the Soyuz for an introduction of the spacecraft to American audiences while Leonov, Stafford, and Slayton gave a tour of the Apollo for the Soviet viewers. Additional joint activities and experiments took place before the crewmembers retired to their original spacecraft for the final time. Remaining joint operations would take place only by radio. The spacecraft undocked and performed a second docking on 19 July to verify the system with the Soyuz active. Total docked time on orbit was a little over one day and twenty-three hours. The two craft flew in formation conducting the solar eclipse experiment and the ultraviolet atmospheric studies, with Slayton in the pilot seat while the service module’s detectors did their job.
Finally, the two spacecraft parted company for the last time. Soyuz successfully reentered and soft landed in Kazakhstan on 21 July with the event being carried on live television around the world. The Apollo spacecraft would stay in orbit for three more days, continuing its experiments. The docking module was jettisoned to gather data for a Doppler gravitation experiment a day before the Apollo spacecraft returned home.
Breathing Exhaust
To the casual observer watching Apollo’s reentry and ocean recovery on television, things seemed to go quite well. However, some serious problems cropped up, which people on the ground didn’t realize at the time. As part of normal Apollo procedures, the command module pilot flies the craft on its reentry profile. This meant that Vance Brand was in the commander’s seat for this phase of the flight, with Stafford in the center seat and Slayton occupying the far-right seat. They had some excess noise in their headsets, in addition to the noises produced by the reentry and the corrective thruster firings from the command module’s thrusters controlling the descent trajectory. As a result, the crew got slightly off sequence from the checklist.
One item in the checklist called for activation of the ELS (Earth landing system), which would deactivate the command module thrusters, jettison the cover over the command module parachutes, and fire the drogue chutes. For whatever reason, Brand didn’t arm the ELS switches, probably because he was waiting for a callout from Stafford or Slayton. When Brand noticed that the capsule had descended through thirty thousand feet without the drogue chutes deploying, he flipped the switches to jettison the cover and fire the drogue parachutes manually. But the thrusters were still active, and they began to fire when the drogue chutes deployed, in an attempt to stabilize the craft. Finally, the ELS switches were flipped on, which turned off the thrusters.
But prior to deployment of the drogue parachutes, the cabin-pressure relief valve opened to equalize the command module’s cabin with outside air pressure. So when the thrusters fired, the rush of outside air into the cabin also sucked in some thruster exhaust. The crew began to cough and feel the effects as their cabin filled with nitrogen tetroxide fumes. Nitrogen tetroxide is highly toxic, and it doesn’t take much to kill a person. When Stafford saw the fumes enter the cabin, he flipped closed the thruster isolation valve switches, which helped a little, but that still left the fumes that had already entered the cabin.
The spacecraft continued a normal descent under the main chutes and experienced a hard splashdown that immediately flipped the capsule upside down in the water before the parachutes were jettisoned. The capsule settled inverted in the water in the stable 2 position. This means that it would not flip upright into the stable 1 position until the three flotation bags on top had been inflated. So the crew was left han
ging in their seat straps, still coughing from the fumes. Brand called for Stafford to grab the oxygen masks normally worn in case of fire. Stafford unstrapped, fell into the Apollo docking tunnel, and had to contort in an odd position to grab the masks, get the masks to the others, and flip the switches that would inflate the flotation bags. Stafford picks up the story from there:
I knew I had a toxic hypoxia because I was having a hard time breathing. I was starting to grunt-breathe, to make sure I had enough pressure in my lungs . . . to keep my head clear. I looked over at Vance, and he was just hanging in his straps. He was unconscious, his arms were [limp] . . . and I said “Vance? Vance?!” He was out cold. . . . His mask had slipped off his face. So I got the mask back on his face [and] hit the high-flow valve. He came to, and he just clobbered me like a mule. People do this when they are unconscious. He just clobbered the hell out of me and knocked me back like that . . . knocked the mask back off his face and passed out again. At this time, I got a hammer lock on his head and put it [back] on him. He struggled some, but not near as bad. Fortunately with the hammer lock I got him back to [consciousness]. And then we got the [capsule] right side up real fast.
