China's Manned spaceship equipped with 52 engines

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Last updated at: (Beijing Time) Wednesday, October 15, 2003

China's Manned spaceship equipped with 52 engines

One leading engineer designing China's first manned spaceship said here Wednesday that Shenzhou-5 was equipped with 52 engines, which ensures its precise move and orbit keeping.

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One leading engineer designing China's first manned spaceship said Wednesday in Jiuquan that Shenzhou-5 was equipped with 52 engines, which ensures its precise move and orbit keeping.

Qin Wenbo, vice chief engineer of the spaceship, said that designing the spaceship's propulsion systems was one of the most demanding tasks.

"It's very difficult to decide when we should ignite the engines and how long they should work," said Qin, who is also vice chief engineer of Shanghai Aerospace Institute.

A total of 28 engines were installed in the propulsion module, eight in the re-entry module and the rest in the orbit module, Qin said.

"After repeated tests since China launched its first spaceship, Shenzhou," Qin said, "it has been proved that our propulsion systems are reliable."

Engineers have also installed two cameras in the re-entry module, which is expected to transmit audio and video signals to the ground command and control center.

Qin said that the headquarters could not only talk to the astronaut, but also monitor physical data of the nation's first spaceman.

Chinese food for Chinese astronauts

While flying China's first spacecraft, the astronaut will enjoy himself over a rich variety of Chinese food.

The recipes for the astronaut include rice cooked with nuts, dates and other delicacies, spicy and sour shredded meat and diced chicken meat. The astronaut will also serve himself with a drink of medicinal herbs and tonics after a meal, according to a top space official.

Su Shuangning, head of the team for developing the astronaut support system, said that the astronaut will have three meals a day while flying in the outer space. "We planned the recipes in a scientific way, in such a way as to ensure that the food will be nutritious enough for space missions while tasting good," he added.

The so-called "space food", food consumed by astronauts while in the outer space, should be limited in quantity and size but highly nutritious while producing no residue.

"It must suit the astronaut's physiological changes in the weightless situation," he said, adding that space flight results in loss of calcium in bones, atrophy of muscles, and a drop in red blood cell count.

The Chinese astronaut will have a choice of 20 plus types of food. In their early space flights, Soviet and American astronauts had liquid or semi-solid food in toothpaste tube-like container, and ate in a mouth-to-mouth manner.

Astronauts now can eat roughly the same way as when they are on earth. According to Su, China-made space food is largely in one-bite size, consisting of meat, fish or dessert. They are coated with an edible protective covering for the convenience of the astronaut who can eat one piece at each bite in order not to produce residue that may keep sputtering in the capsule.

Su also said that Chinese scientists are experimenting with cultivation of vegetables in space stations that can be eaten without cooking.

Conditions for life in Shenzhou-5 are about the same as on earth

The spacecraft comprises three main parts: the propulsion module, orbital module and re-entry module. The orbital and re-entry modules, both airtight, are where the astronaut lives and works during his space journey.

While in space, however, he works, eats and sleeps in the orbital module, according to Su Shuangning, a chief designer for the astronaut system under China's space flight program. "The onboard life support system creates an intra-module environment about the same as on earth," the expert said.

Elaborating, he said that the astronaut system is fitted with sub-systems for air pressure, ventilation, sterilization, temperature and humidity. These ensure normal temperature, moisture and air pressure, including the pressure of oxygen and carbon dioxide, inside the two modules.

Shenzhou-5 operates primarily on preset programming, meaning that the astronaut plays a supplementary role in monitoring the flight and in controlling and running the spaceship in the course of the flight. His task is to observe and record the conditions of the orbiting spaceship for reference of the ground control center.

The astronaut relies mainly on the control center for information. At regular intervals, he reports to the center the conditions of the on-board systems and the flight. He also informs the center of his own conditions -- whether he feels well, whether he sleeps well, whether his appetite is good, as well as his urination and bowel movement.

"In case a mal-function occurs when the spacecraft changes its orbit, the astronaut will step in to control the flight manually," Su said.

While in the space vehicle, the astronaut has three meals a day-- breakfast, lunch and supper, the recipes including canned food, dehydrated rice and fruit, which can be re-hydrated and heated. The so-called "space food," food consumed by astronauts in space, produces limited residue, but is rich in calories and highly digestible. Chinese food is available, the likes of rice cooked with nuts, dates and other delicacies, spicy and sour shredded meat and diced chicken.

The astronaut does not have a bed to sleep on. He has a sleeping bag hung on the interior wall of the spacecraft, and sleeps in it when he is free from the duty of reporting to the ground control center. According to Hu, he will sleep twice during the space journey, for three or four hours at a time.

While flying, the astronaut also writes the flight log, talks with the ground center and with his doctors. "If he has time to spare," the expert said, "he may take photos and videos of the outer space."

Solar panels -- power station for Shenzhou

As Shenzhou-5 departed from its rocket carrier and entered into the preset orbit, the two pairs of solar panels stretched out like huge wings, converting solar energy into electricity to power China's first manned spacecraft.

"With the functions of power supply and charging, the solar panels work like a small power plant," explained Kong Xudong, chief designer of the solar panels. As the spaceship is equipped with batteries with limited capacity, the Sun will be the main source of energy supply.

The panels, built at a cost of more than 10 million yuan (over 1.2 million US dollars), are made of the most advanced lightweight composite materials, according to the expert.

The difficulty in designing and manufacturing lies in how to make the panels adaptable to such uncertainties as the complicated environment and the dense plasma, atomic oxygen and ultraviolet irradiation in the low orbit, which are harmful to the structure and chips of the panels.

The craft circles the Earth once every 90 minutes and has to stand the tests of vast temperature differentials up to 180 degrees centigrade. This requires the solution to the contraction and expansion problems of the materials used.

The experts said that they had developed a testing device that simulates the space environment and used special materials to build the panels.

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