The United States is highly dependent on this Russian-made ＂sharp weapon＂, but Russia is afraid to ＂cut off food＂ for the United States.

　　CCTV News:Faced with the threat of sanctions from the United States, Russian Prime Minister Dmitry Medvedev warned on the 10th that Russia may regard the new sanctions imposed by the United States as an "economic war" declared by the United States to Russia, and Medvedev also said that Russia will take various measures to respond. Some Russian lawmakers even threatened that Russia might restrict the export of RD-180 rocket engines to the United States.

　　Russian Foreign Ministry Spokesperson Zacharova: "All these allegations (of the United States) are groundless. Russia has warned us many times, threatened to use force and issued ‘ An ultimatum ’ It’s useless. For this hostile move by the United States, Russia will begin to prepare countermeasures. "

　　On the same day that Zacharova responded that it would start preparing countermeasures, Rjabusin, chairman of the Budget Committee of the Russian Federation Council, the upper house of parliament, said that Russia’s response measures might include restricting the export of RD-180 rocket engines for military and civilian use to the United States.

　　RD-180 is a rocket engine with two combustion chambers and two nozzles produced by Russian state-owned power machinery research and production consortium, which is used in the first stage of American Cosmos -5 rocket.

　　In 1997, the United States and Russia signed a contract for the sale of 101 RD-180 engines, worth about $1 billion. About two years ago, the US Congress banned the use of these engines after 2019. However, when it was learned that the domestic engine could not be made in the next three years, the US Congress lifted the ban. After that, the United States ordered 20 such engines from Russia.

　　NASA: Contractual obligations should be fulfilled.

　　[News Watch] Why does the United States rely heavily on Russian rocket engines?

　　Some Russian experts believe that if Russia restricts the export of RD-180 rocket engines to the United States, it will cause a major blow to the US space industry. Why is the United States so dependent on this Russian rocket engine?

Why does the United States rely heavily on Russian-made rocket engines? Since 2006, the US Air Force has subcontracted the task of launching Cosmos -5 rockets to the United Launch Alliance Company. In order to maximize profits, the company has long relied only on purchasing Russian-made RD-180 engines instead of developing engines of the same level, resulting in its ability to develop rocket engines gradually declining.

　　RD-180 Engine: Good performance and stable performance.

　　The dependence of the United States on this rocket engine is firstly due to its good performance and stability.

　　RD-180 is a rocket engine with two combustion chambers and two nozzles, produced by Russian state-owned power machinery research and production consortium. It adopts a shared turbopump and a high-pressure staged combustion cycle, with a vacuum thrust of over 400 tons and a specific impulse of 305 meters per second. Specific impulse is an important parameter to measure the efficiency of rocket or aircraft engine, which refers to the impulse generated by the amount of propellant per unit.

　　Experts believe that RD-180 rocket engine is the best product of its kind in the world at present, no matter in terms of thrust, weight or reliability, and it is the first choice for large thrust rocket engines in various countries.

　　The United States began to use the RD-180 engine on its launch vehicle in the 1990s, and successively completed the missions to the moon, Mars, Pluto and Jupiter. According to official data, over the past 20 years, more than 70 rockets with this engine have been successfully launched, with only one failure, which fully proves the stability of this engine.

　　RD-180 engine: low price

　　The second reason why the United States relies on this engine is its low price.

　　According to reports, an RD-180 rocket engine only needs about 10 million US dollars, while the proposal of American companies to develop the same type of engine by themselves is as high as 25 million US dollars.

　　U.S. Deputy Secretary of Defense robert walker once said that once the RD-180 engine is abandoned, the rocket launch cost in the United States will increase greatly, and the single launch cost will increase by at least 40%, which will increase the expenditure of the U.S. military by $1.5 billion to $5 billion in six years.

　　RD-180 engine is irreplaceable in the short term.

　　In addition, for the United States, RD-180 is irreplaceable in the short term. A committee composed of American aerospace experts concluded that it will take at least five years for the United States to develop the same type of engine products, while the current reserve of RD-180 rocket engines in the United States can only last for two years, leaving a gap of nearly three years.

　　Once Russia restricts the export of RD-180 rocket engines to the United States, it will also seriously affect the US military satellite communication system and missile defense system. At present, the space-based infrared system satellites used in these systems are all launched by Cosmos -5 rocket. The lack of RD-180 engine will delay at least 30 launch missions, putting the satellite communication and air defense warning system built in the United States at risk.