April-May 1981:Salyut 6 Expedition 4, part 4

Early in 1978 four pilots arrived in Zvezdny Gorodok for evaluation as cosmonaut trainees. As with all of the CMEA cosmonaut candidates the Soviets had the last word as to who would be selected. The four men were from Cuba and were the first representatives of the western hemisphere to be evaluated for flight aboard a Soviet spaceship. Eventually two of the Cuban pilots were chosen for training.

In September 1979 they were introduced to the two Soviet cosmonauts with whom they would train for one of the crews to make a flight. Although their identities were closely kept secrets at the time the two crews consisted of: Soviet cosmonaut Yuri Romanenko and Cuban Amaldo Tamayo Mendez, 38, and Yevgeni Khrunov (USSR) and Jose Armando Lopez Falcon (Cuba), 30. Tamayo was the first black person to be selected for a Soviet spaceflight and the first black man ever to fly into space.After 12 months of joint training the two crews departed for the Baikonur Cosmodrome on 4 September 1980 after a 2 hour long press conference for CMEA journalists. The launch date was set for 18 September. After the final examinations the Romanenko/Tamayo team was selected.

Late on 18 September the yellow and white autobus with Romanenko and Tamayo aboard stopped at the launch pad and the Taimirs (their call sign) stepped out into the full glare of the TV lights. After their usual round of set speeches the cosmonauts met, and posed for photographs with, Cuban Minister of the Armed Forces Raul Castro who had visited the training centre at Zvezdny the day before. As the Taimirs boarded the Soyuz 38 spaceship on the A-2 carrier rocket, some 2 hours before launch time, the Dniepers (Popov and Ryumin) were contacted by FCC and told to expect new visitors.

Soyuz 38 in Flight

At exactly 1911:03 (all times GMT), 18 September, the engines of the carrier rocket ignited and the Soyuz 38 flight was underway. Following a nominal launch phase the Soyuz 38 spaceship with Romanenko and Tamayo aboard was inserted into near Earth orbit at 1919:50. During the launch the pulse rates of the cosmonauts had been: Tamayo 120 beats/min; Romanenko 102. The initial orbit of the Soyuz 38 was 199 x 273 km and the distance to Salyut 6/Soyuz 37 10,000 km. Following corrections to the trajectory with the Soyuz 38 SKDU on the 4th and 5th orbits the orbital parameters were:height 278 x 320 km; period 90.2 minutes; inclination 51.6°. The Taimirs then settled down to sleep while on Earth the Cuban and Soviet media announced the flight amid great publicity.

When the Taimirs awoke on 19 September the Salyut-Soyuz distance was only about 1,000 km. Shortly afterwards another approach maneouvre was made and the distance shrank to just 23 km before the actual approach was initiated. Soyuz's antenna activated the short range automatic coupling systems as this distance shrank further. Distance was automatically measured and the Soyuz TV camera focussed onto the station's navigation lights with the cosmonauts reporting every step of the operation. At 45 metres distance between the ships the approach velocity was 0.6 m/s. Contact was made at exactly 2049 at a velocity of 0.3 m/s. The coupling latches of Soyuz joined the ship’s together with a force of about 20 tonnes. Pressure was equalised between the ship and station by means of an internal hose and some 3 hours after the docking,at 2352, Tamayo broke open the internal hatches and floated into Salyut to be enthusiastically greeted by Popov and Ryumin. For the FE the fourth meeting with another crew in space must have been a stark contrast to his 175 days of comparative loneliness with Lyakhov on the last flight. At the time of the transfer Salyut was making its 17,128th orbit of the Earth. In a TV report, which included the traditional bread and salt ceremony and exchanges of telegrams with Soviet and Cuban leaders, both Romanenko and Tamayo performed somersaults to show how they had adapted to weightlessness. Both crews then settled down for sleep before beginning their week of experiments.

Aspects of Orbital Flight

September 20 was a short working day, because the doctors wanted to keep as close as possible to the timeline the Dniepers were following; so the Taimirs started several experiments, including the Sugar, Zone and medical ones. Tamayo complained to a doctor that he was not feeling as well as he had done on either of the previous two days. The doctors advised him not to rush about the station but take things easy for a while. Following that advice Tamayo settled down to orbital life, slept well and demonstrated a healthy appetite with a calorie intake of 3,500 to 3,800 calories/day. He also appeared cheerful with a high work capacity, according to the FCC directors. Doctors puzzled over the fact that Tamayo’s blood vessel content had been less than that which is normal for cosmonauts during adaptation to weightlessness.

Looking down on Cuba, Tamayo said that he thought it a wonderful sight. There were no clouds, the sky was clear, the sea looked very beautiful. Later he was able to see the night lights of Havana.

Experiments on Salyut 6

Of course, sightseeing was only for off-duty periods. Most of the Taimirs’ time aboard the station was taken up with the various experiments they had brought with them. In daily TV broadcasts the crew showed the apparatus to viewers and described its function. The experiments were grouped under the headings of medical/biological, psychometric investigations, exploration of natural resources and technological research.

The Cuban experiments, described below, were first conceived in late 1977. Seven administrative agencies, over 50 research institutes and factories and almost 500 technicians and workers brought the plans to fruition.

Medical/Biological Experiments

CORTEX: An experiment designed to study the brain's electrical activity in weightlessness. The human brain produces about one millionth of a volt in electrical output which is monitored to evaluate the neurological state of the subject via an electroencephalogram (EEG). This technique is routine in neurological science. A baseline EEG was obtained pre-flight of the cosmonaut subject’s reactions to stimuli for comparison with in-flight and post-flight EEGs.

The Cortex hardware consisted of a custom-made latex helmet,high grade silver electrodes, earphones, light and sound stimulators, amplifiers to measure the EEG and a 4-track tape recorder. All were stored in a smart leather case. In operation an EEG recording was made from one cerebral hemisphere at a time when the cosmonaut subject was either resting or performing simple mental arithmetic. EEGs were also obtained of visual and auditory evoked potential (EP) which is a measure of the brain’s electrical activity. The visual EPs were obtained by watching a flashing light.

SUPPORT: In this experiment Tamayo was required to wear,for 3 to 6 hours a day, a specially designed adjustable shoe - the Support Sandle 501 - to place a load on the arches of his foot to determine the recovery and readaptation of locomotive stability on return normal gravity conditions.” It had been noted that on return to Earth after long flights cosmonauts had a tendency towards platypodia, especially under load. The changes in gait and posture were attributed to a change in muscular tension. By placing a tension on Tamayo’s feet Cuban specialists aimed to determine whether changes in the arches of the feet were important in the disturbance of posture after return to Earth. As a control Romanenko did not wear the shoes. The experiment is to be repeated in future long-duration flights.

ANTHROPOMETRY: An experiment with the objective of determining the changes in muscular mass and bone structure in weightlessness by use of calipers to examine adipose tissue and to stimulate it.

BLOOD CIRCULATION: A series of electrocardiograms taken before, during and after the flight determined the bioelectrical alterations of the heart during adaptation to weightlessness and readaptation to 1G. The experiment involved monitoring the blood circulation. The Pneumatik 1 and Chibis suit devices were used to simulate 1G during the flight to characterise the adaptation and counteract the feelings created by blood rushing towards the cranial region.

A series of tests and samples were made before the flight and immediately afterwards to determine the cosmonaut's adaptation to, and the effects of, weightlessness. In the VISION experiment the clinical and functional states of the cosmonauts’ eyes was determined by an opthalmic investigation common to all Soviet flights but with new parameters added by Cuban specialists. The BALANCE experiment aimed at determining changes in Tamayo’s hydro-mineral balance and comparing them with Romanenko’s to determine any differences between a cosmonaut from a European climate and one from the tropics. The test series included water intake, urine excretion, body weight and blood tests to determine the content of sodium, calcium, magnesium, chlorides, creatine and other substances. The IMMUNITY experiment was aimed at the determination of characterising the changes in proteins and minerals directly related to the body's natural defences during spaceflight. Blood samples obtained before and after the flight were analysed for the content of immuniglobin, antibodies and other proteins and minerals involved in immunological reactions. Finally, the STRESS experiment determined changes produced in Tamayo’s hormonal characteristics and carbohydrates and lipid metabolism.

SUGAR: (although it might be classed as a biology experiment the Cubans termed sugar a technological one. That classification is retained here). It consisted of monitoring the growth of a sucrose mono-crystal in the crystallizer device built in Cuba. The device comprised a chamber containing four crystals submerged in different solutions which were grown for 72 hours and photographed periodically with the GDR-made EE-2 manual camera. It was the first experiment to grow single crystals of an organic compound in space. On TV Tamayo said he was surprised to see how fast the growth of the crystals had been.

ZONE: This experiment aimed at simultaneous studies of the dissolution of sucrose mono-crystals using a novel technique consisting of dissolving a solid material within a liquid area and then crystallising it using different temperature gradients. Tamayo displayed one of the containers for the experiment on TV showing three sucrose crystals inside it.

Psychometric Experiments

COORDINATION: Study of the effects of weightlessness on voluntary motor function was the basis of this experiment. Pre-flight and in-flight results were compared of a simple test to assess the psychomotor ability of Tamayo. A Cuban-built coordinograph was used for the test. By turning two cranks simultaneously, one with the left hand one with the right, Tamayo had to guide the point of a crayon between the double outline of a geometric figure without touching the line, at varying speeds.

PERCEPTION: With Cuban-built equipment based on commercial models this experiment evaluated the visual, tactile and muscular sensitivity of Tamayo.

QUESTIONNAIRE: By answering a series of set question throughout the flight psychologists could assess the cosmonauts’ reactions and mood, including behaviour. Questions ranged from “how are you adapting?” to specific aspects of the flight.

The Taimirs’ Return

In addition to their experiments the Taimirs also aided the Dniepers in the first round of their preparations for returning to Earth. Because the main crew were scheduled to return by mid-October (specifically stated by a Soviet spokesman) the Taimirs were not required to leave their Soyuz 38 ship for the Dniepers and return in Soyuz 37. Because of this the time normally taken in exchanging seats was used to pack some of the experiment results into Soyuz 38 from the main expedition as well as their own.

On 25 September, just 24 hours before their return, a short burn was conducted with the Soyuz 38 SKDU to check its operation and refine the reentry track. Early next morning (26 September) the crew had breakfast and bade farewell to the main crew. The send off was slightly more emotional than usual. At 0925 the Taimirs crossed into Soyuz 38 and closed the hatches. They donned their spacesuits and conducted the normal series of pressurisation checks. At 1234, over the Soviet Far East, the two ships parted. The separation maneouvre was performed and the Taimirs watched Salyut 6 slowly drift away.

On the last orbit before retrofire, in accordance with tradition, Vladimir Shatalov told the crew about their duties after entry into the atmosphere. He reminded them that they were to be patient if the helicopters were a little late in reaching them. It would be after dark and the helicopters would have to look for them with searchlights. Retrofire, at 1505, lasted for 180s and the ship was pulled to Earth. At 1526, at an altitude of 144 km, the three sections of Soyuz 38 separated and at 1531 the descent cabin entered the upper layers of the atmosphere. The crew experienced overloads of 4G while the external temperature topped 3,000°C. At 1540 radio contact was reestablished and by 1550 the parachutes had unfurled. At a height of about 1 m the retrorockets at the base of the descent cabin fired to slow the velocity to 3.7 m/s. Soyuz 38 had made a soft landing some 175 km SE of Dzezkazgan at 1554 just 3 km from the designated target. It was one of the most accurate landings in the Soviet space programme.

Looking slightly weary, the cosmonauts were flown from the landing site to Dzezkazgan and then to Baikonur where, just 24 hours later,Aleksei Leonov told reporters that they were in excellent shape with all signs of stress and weariness gone. The cosmonauts were accorded several national and party honours from both countries. They were received in the Kremlin on 1 October. The Soyuz 38 descent cabin is to be presented to a Cuban museum.

Progress 11 In Flight

Although the Dniepers were scheduled to return home by mid-October much work still remained for them to do before they could pack their bags. To ensure that Salyut 6 could be re-used if necessary, or brought out of orbit without using the suspect main propulsion system, the Soviets took the opportunity to dock another Progress cargo ship.

Progress 11 lifted off from Baikonur at 1510 on 28 September into an initial orbit of 193 x 279 km; period 88.8 minutes-, incl. 51.6°. After a nominal 2 day rendezvous sequence the cargo ship docked with Salyut's aft docking unit at 1703 (30 September). The cargoes delivered were mostly food, regenerators for the life-support system, pieces of equipment and water. The cosmonauts began the unloading quickly and by 4 October all the cargoes had been unloaded and the loading up of the items of no further use began. On 8 October the SKDU of Progress 11 was used to trim the orbit of the three spacecraft complex.

Simultaneously with the unloading, the cosmonauts began their descent programme which would ensure they were ready for the readaptation to the Earth's gravity. The programme included regular exercises and time wearing the Chibis suit;regular taking of salt and water supplements to rectify the partial dehydration caused by weightless conditions, and blood sampling. They also cleaned the station, leaving it as they would wish to find it, and effected a few minor repairs. Generally they worked faster than scheduled which indicated to the FCC physicians their excellent health. The final large-scale experiment before deactivation of the equipment was one designed to test the structural stability of the complex.

Descent To Earth

Early on 11 October the Dniepers were awoken to begin their preparations for the return. After breakfast the men packed the final items of scientific interest for return and, about 20 minutes before crossing into Soyuz 37, took some final pictures of the Earth. The cosmonauts had tested the Soyuz 37 SKDU the day before and all that remained once the lights had been switched off was to close the hatches and wait for the undocking signal.

At about 0630 the Salyut 6/Progress 11 and Soyuz 37 parted company. The cosmonauts had left Salyut as they had arrived, with a Progress cargo ship attached to the aft docking unit. The descent was normal following retrofire at about 0900. Throughout the descent the cosmonauts provided a running commentary. The touchdown, at 0950, was shown on TV some time later. The point of landing was a field some 180 km SE of Dzhezkazgan. The recovery helicopters were soon at the scene and the physicians erected a tent for the medical examinations. Ryumin was first out of the cabin and surprised the doctors by walking unaided to the lounge chairs provided for them.

The medical examinations showed that they had stood up well to the long flight of 185 days. The cosmonauts displayed a jaunty humour with the pressmen at the landing site and it was soon clear that Popov and Ryumin would readapt faster than any previous crew.

Returning to Baikonur the same day the cosmonauts looked happy and fit as they stepped from the aircraft. They were taken to the Hotel Kosmanavt and left to sleep in readiness for a long series of medical tests.

Readaptation to Earth’s Gravity

Exactly 20 hours after landing, and following their first sleep back on Earth, the cosmonauts surprised the doctors by taking an unaided walk lasting 1,500 paces or just about half an hour. During the walk their pulse rate quickened by just 15 to 20 beats. The medics stated that this was the fastest that any crew had overcome the first acute stages of readaptation. The crew were then allowed to eat their first real food at the same cafe where they had dined before departing for the Salyut station on 9 April. The meal consisted of salad, yoghurt, ham, pickled cucumbers, Ukrainian cabbage soup and bread given to them at the landing site. Despite their good condition, the medics said that they did not intend shortening the Dniepers’ period of post-flight tests.

The cosmonauts' day was divided into 32 separate activities, or points, 20 of them related to medicine. Breakfast, for example,featured as point 10 on the schedule. The unplanned walk was entered as a new point called “loading in the open air” The days lasted for 12 hours with some free time at the end of them. The cosmonauts requested a daily 30 minute chat with journalists in between medicals and exercises. By 15 October the men were able to play tennis. Talking to a reporter during one of his walks Ryumin said that in his opinion the only real problem with the execution of a year-long flight in space was the ability of FCC to keep the cosmonauts active and interested. With a meaningful and varied work routine a 12 month flight was possible, Ryumin said; “indeed, if it was needed to prove we could go to Mars then Leonid (Popov) and I would volunteer right now.”