Aerospace |
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Taming The
Fire
The machinery-building factory of Vintai is where Russians test their rocket engines. Located some 50 km from the city of Samara, the test site is called "factory" because of the old Russian tradition to hide everything pertaining to the defence sphere. The facility is fully independent, receiving only electrical power, kerosene and peroxide from the outside world. Rocket fuel is made by the local oxygen plant at the village of Vintai.
Sustained TestsThe RD-7 is in use on the first stages of the Soyuz launcher. Each and every such engine goes through a thorough testing before installation into the rocket. Usually, burn tests last for 280 seconds. In actual space flights, the Soyuz' central engine works for 320 seconds and strap-on engines for 120 seconds. "When we work for 320 seconds and more, the roar is clearly heard
in Toliatti and at the Samara airport. Sometimes sustained tests cause glass
After enduring these tests, engines rarely go into space. However, there have been a few cases when they either did fly or were put through the sustained test procedure one more time. Designed for single use, some RD-7s were put through a series of vigorous tests, showing outstanding reliability and strength. "Some of our engines successfully went through three sustained tests," says Igor Fatuev, chief designer for the RD-7 and deputy general designer at Energomash. Basing on this experience, Russian designers developed the RD-170 and RD-180 next-generation engines for repeated usage.
The Vertical StandThe factory in Vintai has several test facilities, the most powerful being the vertical stand. Its design strength of 600 t is considerably higher than the RD-7's thrust of 75 t and the NK-33's of 180 t. Operated by over 1,000 people, the vertical stand had its first fire test on 30 August 1961. Although built so long ago, the stand has been repeatedly modified, and now represents a highly-automated facility. "In fact, the stand is a stationary rocket with all essential systems - control, measuring, life-support, protection etc.," says Anatoly Anenkov. Over 300 parameters are measured, reordered and processed at its computing center. "Launch preparations" go on automatically, including building up pressure and controlling temperatures of the flame. Although it is quite difficult to calculate the exact number of tests performed since 1961, rough estimations say the figure is roughly 10,000. The General Director admits that there have been some failures on rocket engines during testing, but the steady construction of the stand allowed it to remain operational. If something goes wrong, the automatic control system of the stand closes fuel valves immediately. Fuel flow can also be terminated manually by the leading test engineer, who has a "red button" on his desk. The job is not for those with bad nerves. "I worked for 18 years at this stand and may say that only 2-3 people out of ten coming to work at the facility remain here because of the very high psychological load. To work here you must have quick reactions and intuition," says Anatoly Anenkov. On one occasion, he says, the leading test engineer managed to press the button 0.01 sec before the engine failed, narrowly preventing explosion.
Listening To The FlameI was lucky to get in a group of journalists invited to see the test on an RD-7. It lasted for a relatively short time, with 30 seconds at the nominal mode and several seconds at full throttle. We stood at an open spot some 500 ft away from the flame. Although normally people must not be on exposed positions like this when burn tests are being conducted, the General Director made an exception for the journalists. According to the Anatoly Anenkov, at nominal the engine devours 240 kg of oxygen and 100 kg of kerosene, with the flame temperature ranging between 1,300-1,400 degree Celsius. The combination of kerosene and oxygen is claimed to be the most environmentally-friendly pair in rocketry. "When ecologists come to see the place, I am always asking them where else they saw such a beautiful maiden nature all around," says Anenkov. My own eyes agreed. The surroundings did look beautiful. The test was not that dangerous - the reliability of the RD-7 is 0.998, Igor Fatuev told us. At the same time, it was not that pleasant to stay so close to the stand. I found myself unable to listen to the flame for more than ten seconds, with my hands "automatically" trying to reduce the pressure on ear-drums by inserting fingers in the openings. |
Anatoly Anenkov,
General Director of the Vintai factory, says its construction began in 1958.
Before completion in 1961. the Russians tested their rocket engines near
Moscow, including those for the world's first manned flight by Yuri Gagarin.
Engines for all other manned flights, starting from Titov's, were tested
here, in Vintai. Anenkov recalls, "We started off with the Voskhod
booster, continuing with the 7N1 Lunnik ("Mooner") powered by
RD-33s." The latter were under tests at Vintai from 1968. "On
17 May 1974 we performed the last fire test on this formidable engine, and
then shifted to the RD-7, which still remains the primary engine for us,"
says Anenkov adding that the factory has recently been modified for more
advanced designs.
windows in nearby
houses to break," confesses the General Director. The windows almost
always break when the factory conducts prolonged tests lasting up to 400
seconds. Called "sustained tests," those are performed to understand
the ultimate abilities of the engine.