Longyun (rocket engine)

{{Short description|Rocket engine}}

{{redirect|Longyun|the Chinese politician|Long Yun}}

{{distinguish|Lingyun (rocket engine)}}

{{infobox rocket engine

|name = Lingyun

|image =

|image_size =

|caption =

|country_of_origin = China

|date =

|first_date =

|last_date =

|designer =

|manufacturer = Jiuzhou Yunjian

|purpose =

|associated =

|predecessor =

|successor =

|status = Under development

|throttle_range = 30%~100%

|type = Liquid

|oxidizer = LOX

|fuel = liquid methane

|mixture_ratio =

|cycle = Gas-generator cycle

|pumps =

|description =

|combustion_chamber=

|nozzle_ratio =

|thrust =

|thrust_at_altitude=

|thrust(Vac) = {{convert|770.2|kN|lbf|lk=on}}

|thrust(SL) = {{convert|686.5|kN|lbf|lk=on}}

|thrust_to_weight=

|chamber_pressure=

|specific_impulse=

|specific_impulse_vacuum=350s

|specific_impulse_sea_level=290s

|total_impulse =

|burn_time =

|gimbal =

|capacity =

|dimensions =

|length =

|diameter =

|dry_weight ={{convert|880|kg|lb|abbr=on}}

|used_in =

|notes = {{cite web |title=Longyun Engine JiuZhou Cloud Arrow (Beijing) Space Technology Co., Ltd. |url=http://en.jzyjspace.com/product/27.html |website=en.jzyjspace.com}}

}}

The Longyun ({{zh|s=龙云|p=Lóngyún}}, lit. Dragon Clouds) is a gas-generator cycle rocket engine burning liquid methane and liquid oxygen under development by Jiuzhou Yunjian.

History

In 2018, the gas generator test for the Longyun engine was completed.{{cite web |last1=Jones |first1=Andrew |title=Chinese Linkspace reaches 300 meters with launch and landing test |url=https://spacenews.com/chinese-linkspace-reaches-300-meters-with-launch-and-landing-test/ |website=SpaceNews |access-date=15 March 2024 |date=12 August 2019}} The engine completed multiple start-up hot test runs in May 2021.{{cite web |title=JiuZhou YunJian "LongYun" engine has completed multiple start-up hot test runs_JiuZhou Cloud Arrow (Beijing) Space Technology Co., Ltd. |url=http://en.jzyjspace.com/news/46.html |website=en.jzyjspace.com |access-date=15 March 2024}} In October 2021, launch startup Rocket Pi signed a deal to use the Longyun engine to power its Darwin-1 reusable launch vehicle.{{cite web |last1=Jones |first1=Andrew |title=New Chinese launch firm signs deal for reusable rocket engines |url=https://spacenews.com/new-chinese-launch-firm-signs-deal-for-reusable-rocket-engines/ |website=SpaceNews |access-date=15 March 2024 |date=31 October 2021}}

Space Epoch conducted a ground test of a 4.2-meter stainless steel stage powered by the Longyun engine in January 2023.{{cite web |last1=Alaieva |first1=Liliia |title=The Chinese are preparing to launch a "miniature Starship" |url=https://universemagazine.com/en/chinese-startup-tests-miniature-starship/ |website=The Universe Magazine |access-date=15 March 2024 |date=20 January 2023}}

In April 2024, Longyun passed a long duration hot firing test with the servo mechanism rotating to the maximum angle of ±8°. The engine has also reportedly passed the customer acceptance test.{{cite web |title=九州云箭 70 吨级“龙云”火箭发动机高压泵后热摇摆试验圆满成功 |url=https://www.ithome.com/0/683/938.htm |website=www.ithome.com |publisher=ithome}}

References