3,000 second at a time! Compatibility between ZQ-2 control system and second-stage vernier engine verified

2020-07-16 18:27:47 LANDSPACE 1782

On July 14, 2020, Zhuque-2 (ZQ-2), a carrier rocket independently developed by LandSpace and also the first LOX+LCH4 Liquid Rocket Engine(LRE)in China, was tested to verify the compatibility between ZQ-2’s control system and the second-stage vernier engine. The latter, a 10-ton LOX+LCH4 LRE, passed a 3,000-second hot-firing test run, thereby setting a record for the time of one test on a pump-fed cryogenic LRE in China. It reached the domestic advanced level, with all of its technical data satisfying the general requirements of the rocket.


For the first time, sub-cooled propellant loading and operating conditions were assessed in the test. The success indicates that TQ-11 is the first lOX+LCH4 engine passing the test on propellant sub-cooling, and LandSpace is the sole Chinese private aerospace enterprise mastering the technique in propellant sub-cooling and possessing the capacity for the sub-cooling test, with many of the engine’s performance parameters attaining the domestic advanced level.

ZQ-2’s electromechanical servo featured high reliability, great testability, good maintainability, lightweight, and low costs. In this test, the engine was controlled through the electromechanical servo for assessing oscillation, including sine wave, square wave, and triangle wave. The assessment covered the maximum sway and the frequency range of 0.1-25 Hz. The static and dynamic characteristics of the servo were identified and its performance met the requirements of the rocket’s control system. The oscillation program and the electromechanical servo of the engine passed the test, demonstrating the compatibility and coordination between the engine and the control system.


As proved by the test, TQ-11

1. is the only LOX+LCH4 engine tested with total test duration exceeding 10,000 seconds

This type of engine has been tested for over 10,000 seconds in total. A single-engine has been tested for 4,500 seconds, over 6 times its rated operating time, while one test lasted for 3,000 seconds. All tops the highest records of cryogenic LREs in China. The design, production, assembly quality, and work reliability of the engine have been fully assessed.

2. is China's first LOX+LCH4 engine adopting sub-cooled and cryogenic propellant.

LOX and LCH4 propellants were sub-cooled through heat change with liquid nitrogen. Sub-cooling enabled increase in propellant density, decrease in saturated vapor pressure, increase in engine thrust and thrust-to-weight ratio, reduction in rocket size, and it is a key measure in expanding payload capability and reducing launch costs.

Other tests included generator sequence fluctuation test, assessment of continuous regulation of mixture ratio, assessment of the oxygen & methane pressurization system, and verification of the simulated flight procedure. It was found that the technical data of the engine meet the rocket flight requirements. In the future, the engine would be tested under extreme boundary conditions and its maximum life span would be explored. We intend to provide ZQ-2 with a robust engine and lay a solid foundation for reusable rocket technology.

关于“天鹊”10吨级液氧甲烷发动机  (TQ-11)

TQ-11, as the only Chinese multi-nozzle LOX+LCH4 Liquid Rocket Engine (LRE), is the second-stage vernier engine of ZhuQue-2 (ZQ-2) Metha-LOX Launch Vehicle. With a vacuum thrust of 8.2 ton, TQ-11 adopts a gas generator circulation and a co-axial turbo-pump for 4 thrust chambers, shares valves with the 80-ton main engine, and forms the second-stage propulsion system of ZQ-2.

About Zhuque-2 (ZQ-2)

ZQ-2, a medium-scale LOX+LCH4 carrier rocket independently developed by LandSpace, is the first of its kind developed in China. The 49.5-meter-long ZQ-2 rocket measures 3.35 meters in diameter and produces 268 ton of lift-off thrust at 216 ton in mass. It can deliver 6-ton payloads into 200-kilometer LEO or 4-ton payloads into 500-kilometer SSO.

 The ZQ-2 family, which is designed based on the design concept of "one combination of propellants, one rocket body diameter and two types of engines", forms a series of liquid launch vehicles with capacity ranging from several tons to tens of tons and covering low, medium and high earth orbits via different design combinations.