YF-100K Development in April 2024 (+TQ-15A)
This post was originally published on Ko-fi on May 3rd 2024.
Last month saw a few ignitions of the YF-100K leading to new data from the firings. Two tests were reported in April so let's recap!
April 12th
April 12th reportedly had an engine perform what Chinese media are calling a 'twice-ignition' test. This test had the engine fire once, wait a set period, and fire again without anything being modified by engineers. The test was believed to be a demonstration of an in-flight restart, likely for an entry or landing burn.
Media also highlighted that the specific engine used was ignited 30 times over 15 separate tests, they did not specify what kinds of test. This singular engine is now believed to have surpassed 3,900 seconds of firings according to the Academy of Aerospace Propulsion Technology, which is a subsidiary of China Aerospace Science and Technology Corporation.
According to Gao Xinhui, a Senior Researcher at the academy, the engine is still close in heritage to the YF-100. He also said the following:
"Through continuous improvements and tests, the new engine has had stronger power and better operating efficiency compared with existing types. Our engineers have also extensively reduced its overall weight and size," - "We will continue to carry out such tests to check how many times it can be reused, and examine its performance in each test."
April 28th
Four YF-100K's reportedly fired up for the first time together on the 29th. This test is believed to have verified two things: the combined ignition of four YF-100K's, and the thermal environment around the engines.
All four engines are thought to have achieved 130 tons of thrust each for a total of 520 tons of thrust for an unspecified amount of time. What is known according to Li Bin, a Deputy Head at the academy, was that the test simulated a lift-off scenario.
Little detail is known about the test configuration but it is believed to be similar in dimensions to the Long March 12, which currently has tanks being manufactured for a debut flight later this year. The Long March 12 may be the first vehicle to fly the YF-100K's.
April 30th TQ-15A
LandSpace has also been firing its TQ-15A engines this month since installing a niobium alloy nozzle. These firings are likely ahead of the second batch of Zhuque-2's, which I believe will use the engine, and mass production.
According to LandSpace, the most recently tested engine was fired nine times, for a total of 2,030 seconds, before being inspected and fired for a further 17 times, and 2,740 seconds, This single engine has fired 26 separate times for 4,770 seconds. Notably, the engine was not majorly cleaned between each firing and surpassed the 20 relights that LandSpace has been believed to be aiming for.
In an unforeseen turn of events, Xinhua News was on site for the test firings with LandSpace and either knowingly or unknowingly released images of the injector plate of the TQ-15A engine. In the image, you can see where each injector terminates as well as the nine 'zones' they create in the engine, these zones are likely to solve combustion instability like with the F-1 engine. (By see I mean approximate, I have a diagram but it is awful. If I can find another image inside I will make a higher-quality one.)
LandSpace believes that these firings have laid a solid foundation for mass production and that the niobium alloy nozzle is ready for flight. This could mean that the four launches of Zhuque-2 this year are imminent, but that remains to be seen.