{"id":25331,"date":"2026-06-20T19:03:13","date_gmt":"2026-06-20T11:03:13","guid":{"rendered":"https:\/\/wp-productionenv-bjg9h2g2bgg5b8aa.southeastasia-01.azurewebsites.net\/news\/analysis-of-yf-115-which-is-widely-used-in-the-liquid-oxygen-kerosene-engine-of-the-second-stage-of-my-countrys-new-generation-medium-sized-launch-vehicle\/"},"modified":"2026-06-20T19:03:13","modified_gmt":"2026-06-20T11:03:13","slug":"analysis-of-yf-115-which-is-widely-used-in-the-liquid-oxygen-kerosene-engine-of-the-second-stage-of-my-countrys-new-generation-medium-sized-launch-vehicle","status":"publish","type":"post","link":"https:\/\/starpath.global\/news\/analysis-of-yf-115-which-is-widely-used-in-the-liquid-oxygen-kerosene-engine-of-the-second-stage-of-my-countrys-new-generation-medium-sized-launch-vehicle\/","title":{"rendered":"Analysis of YF-115, which is widely used in the liquid oxygen kerosene engine of the second stage of my country&#8217;s new generation medium-sized launch vehicle"},"content":{"rendered":"<p>1. Basic information<\/p>\n<p>YF-115 is a high-altitude oxygen-rich afterburning cycle liquid oxygen kerosene engine developed by the Sixth Academy of Aerospace Science and Technology. It forms a series with the YF-100 engine and is widely used in my country&#8217;s new generation launch vehicle. According to vector control capabilities, YF-115 is divided into YF-115F (one-way swing in front of the pump), YF-115G (two-way swing in front of the pump \u00b15\u00b0), and YF-115H (no swing capability). Subsequent improvements include YF-115B and Tianhuo-11.<\/p>\n<p>2. Core parameters<\/p>\n<p>(1) Structural parameters<\/p>\n<p>length<\/p>\n<p>quality<\/p>\n<p>combustion chamber<\/p>\n<p>Number of turbine pump rotors<\/p>\n<p>Nozzle area ratio<\/p>\n<p>2.325 m<\/p>\n<p>540 kg<\/p>\n<p>1<\/p>\n<p>1<\/p>\n<p>88<\/p>\n<p>(2) Performance parameters<\/p>\n<p>Thrust (vacuum)<\/p>\n<p>Specific impulse (vacuum)<\/p>\n<p>combustion chamber pressure<\/p>\n<p>Thrust to weight ratio<\/p>\n<p>180 kN<\/p>\n<p>3349 m\/s<\/p>\n<p>12 MPa<\/p>\n<p>36<\/p>\n<p>3. Development experience<\/p>\n<p>In 2002, while developing the YF-100, my country started the program demonstration and engineering design of the YF-115 using its breakthrough liquid oxygen kerosene supplementary combustion cycle engine technology. In 2005, YF-115 successfully conducted its first gas generator-turbine pump joint test. In 2006, the YF-115 successfully underwent complete machine testing. In 2012, YF-115 completed the preliminary prototype development and entered the sample development stage. In April 2013, the YF-115 was installed on the second stage of the Long March 6 and successfully conducted a hot test run. On August 29, 2014, four YF-115 machines were installed in parallel on the second stage of the Long March 7, and the power system test of the second stage of the Long March 7 was successfully conducted. On September 20, 2015, YF-115 successfully made its first flight mounted on the Long March 6 rocket.<\/p>\n<p>4. Installed application<\/p>\n<p>Long March 6: The second stage of the Long March 6 is 2.25 meters in diameter, equipped with one YF-115, has a double-swing engine, and does not have a secondary start.<\/p>\n<p>Long March 6A: The second stage of the Long March 6A has a diameter of 3.35 meters and is equipped with a YF-115 engine. The engine swings in both directions to provide control torque. During the secondary two-start mission, the engine was replaced with a YF-115B.<\/p>\n<p>Long March 6C: The second stage of the Long March 6C has a diameter of 2.9 meters. It is equipped with one YF-115 engine at one start. The engine swings in two directions to provide control torque. The theory supports secondary ignition. The YF-115B engine is used when the secondary ignition is supported.<\/p>\n<p>Long March 7: The second stage of Long March 7 has a diameter of 3.35 meters and a length of 15.445 meters. It is equipped with two non-swinging YF-115s and two double-swinging YF-115s, with a total thrust of 720 kN (73.47 tons) and a thrust-to-weight ratio of 0.73.<\/p>\n<p>Long March 7A: The second stage of the Long March 7A has a diameter of 3.35 meters, with 2 non-oscillating YF-115s and 2 double-swinging YF-115s.<\/p>\n<p>Long March 12: The Long March 12 has a diameter of 3.8 meters and is equipped with two YF-115Bs. The engine has double swing and can be started twice.<\/p>\n<p>5. Evaluation<\/p>\n<p>As a vacuum-improved engine, the YF-115 nozzle area is relatively conservative and the specific impulse is unsatisfactory. Among my country&#8217;s new generation of medium-sized launch vehicles, the capacity of any rocket equipped with YF-115 is much lower than that of similar rockets that do not use YF-115. However, it is an important product for my country&#8217;s early exploration and practice in the field of afterburning cycle technology. , YF-115 has accumulated valuable high-pressure afterburning cycle engine design, manufacturing and testing experience for our country, making our country the second country to fully master the liquid oxygen kerosene high-pressure afterburning cycle engine technology, filling a gap in the upper stage power of my country&#8217;s new generation rocket at that time, and replacing the traditional plan of the old Long March rocket&#8217;s second-stage main engine plus a touring engine.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>1. Basic information YF-115 is a high-altitude oxygen-rich afterburning cycle liquid oxygen kerosene engine developed by the Sixth Academy of Aerospace Science and Technology. It forms a series with the YF-100 engine and is widely used in my country&#8217;s new generation launch vehicle. According to vector control capabilities, YF-115 is divided into YF-115F (one-way swing [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"inline_featured_image":false,"footnotes":"","_links_to":"","_links_to_target":""},"categories":[2],"tags":[],"class_list":["post-25331","post","type-post","status-publish","format-standard","hentry","category-news"],"acf":[],"_links":{"self":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts\/25331"}],"collection":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/comments?post=25331"}],"version-history":[{"count":0,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts\/25331\/revisions"}],"wp:attachment":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/media?parent=25331"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/categories?post=25331"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/tags?post=25331"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}