Military of China, force comment.
Military of China, force comment.

chart: Long March II FT1 rocket Xinhua News Agency reporters Gao Wei and Sun Yanxin preparation.

Xinhua (microblogging) Beijing October 2 (Reporter Wang), “Temple” was successfully launched, opened China’s first manned space mission space rendezvous and docking the big screen. Has a “sky,” said the Long March II F rocket has to assume a new historical mission – help Temple One target aircraft and unmanned spacecraft, Shenzhou VIII “space meet.”

although still called “the long two F” or called a modified “long two F”, but a new look from outside to inside the rocket, carrying capacity and in the orbit accuracy has greatly improved. With the researchers as saying: “This is a new rocket.”

spend Von Karman fairing curve

China Aerospace Science and Technology Corporation a hospital rocket designer Jing Mu-chun said that the improved long two F rocket target launch vehicle and spacecraft with two states, carrying capacity of 8.6 tons and 8.1 tons, compared with the traditional status of “long two F” increased by 0.6 tons and 0.1 tons. As the unmanned target aircraft, the launch of Long F of this state to cancel the escape tower rocket device.

in launching the “One Temple”, the rocket is the biggest change on the shape of the fairing, not only by the previous length of 10.7 meters to 12.7 meters, the maximum diameter of 3.8 m from the previous to 4.2 m , but also used the head of the von Karman flow wire curve, which is the most significant changes to attract the public eye.

Von Karman is the master of American engineering mechanics, the theory of space technology pioneer. Von Karman curve is based on his research results and draw the curve.

“fairing increases lengthened, and the ‘Temple One’ is closely related to the volume of ‘Temple One’ bulky than the Shenzhou spacecraft.” Jing Mu-chun said, “the head fairing design uses The significance of von Karman curve to better reduce the air resistance, reduce the load impact. “

However, the production of von Karman curve fairing, it is not as easy as Tannangquwu with high technical difficulty. Jing Mu-chun explains; “different from before, after von Karman curve is not a flat head start, involving a number of complex processing and issue of material forming.”

“long two F” development team conducted a series of painstaking research process, verification, finally will use the von Karman curve fairing from theory into reality.

addition to changes in the shape of the fairing, the rocket booster rocket body structure of the system of internal top shape has changed from the original ellipsoid into a cone. Jing Mu-chun, said: “This can carry more propellant, the rocket carrying capacity by more than 100 kilograms, which is not on the manned space program has a small contribution.”

used to use two sets of group to improve the accuracy

any rocket blasted off after the predetermined trajectory has been able to, and ultimately to precisely target into orbit, mainly by the rocket’s control system to complete the process.

introduced, according to Jing Mu-chun, improved long two F rocket control system is a new system, from the use of the program, principles, specific equipment, software and hardware aspects of the traditional status of “long two F” changed a lot, which is equivalent to the replacement of a new rocket “brain.”

inertial measurement unit, referred to as “used to group” is the core of the rocket control system, affect the accuracy of the key components of the rocket into orbit.

and the previous two F rocket compared to the long, long two F rocket improved control system of a major change is the abolition of the original air-gyro platform, as a group with two measuring devices are used. As a result, can better meet the rocket in the yaw direction of the pitch maneuver requirements.

With the above-guided tools, improved long two F rocket guidance system, the first use of the iterative guidance technology. These practices are designed to meet the rocket into orbit rendezvous and docking mission to the accuracy and reliability of rail and adaptive and other requirements.

However, the first rendezvous and docking mission to the “Temple” of the orbit is not very high accuracy requirements, but the “Shenzhou 8″ high precision of the orbit. Therefore, the project developed two sets of guidance in selecting the program: When the target launch vehicle, the rocket using only perturbation guidance; when launching spacecraft, the rocket a “perturbation + iteration” combination guidance.

reporter learned that as many as 170 in a number of technological change in the rocket system, far more than this number of important changes. Long two F rocket development team also power systems, telemetry systems and fault detection systems, a series of measures to continuously improve the reliability of the rocket, which is an eternal, endless process.