From the morning DPC. Station is experiencing and will continue to experience S- and Ku band communications issues/blockages due the solar array SARJs or TARJs (hard to tell which because of static) being locked due to contamination concerns from the Soyuz. The crew asked about power concerns and were told there are none. A scheduled PAO event was cancelled. All window covers are to remain closed due to contamination concerns as well.
<snip>The high beta angle is pushing Soyuz MS-22's SOTR system harder than other times though it had to be designed for these conditions. This I seem to recall not the first SOTR loop failure in the history of Soyuz, Progress and Soyuz derived station Service module components.
Quote from: russianhalo117 on 12/15/2022 06:33 am<snip>The high beta angle is pushing Soyuz MS-22's SOTR system harder than other times though it had to be designed for these conditions. This I seem to recall not the first SOTR loop failure in the history of Soyuz, Progress and Soyuz derived station Service module components.Might a temporary shade be rigged, as was for Skylab?Or, reprogram the solar tracking function, or the standard ISS attitude, and use the USOS solar panels,and/or the ISS body, to shade the spacecraft, at least some of the time?
Dec 14, 2022As a spacewalk was being planned to move a radiator onto a new module on the space station a cooling system on the Soyuz MS-22 spacecraft was seen leaking into space. This resulted in the space walk being cancelled and the crew investigating this problem while trying to limit effects on the station's scientific experiments.
Some reports (eg Ars) are speculating that the coolant is ammonia, presumably because it is used in the US orbital segment external loop (the internal loop uses water).However note that the Russian designs have preferred to use silicone oil in the external loop (eg mentioned re:Mir on page 43, but AIUI the ROS currently uses it) and water/glycol for the internal loop (see page 7).While ammonia will evaporate harmlessly (as it has in previous ISS ammonia leak incidents), silicone oil would not.
Two redundant internal thermal loops are filled with Triol, water with a 30 percent solution of glycerin, which lowers the freezing point to –7°C. Triol also contains antifreeze, biocide, and ultraviolet-light-sensitive additives to aid in leak detection. Internal loops are considered cooling loops. Two redundant external thermal loops are filled with polymethyl siloxane. External thermal loops interface with internal loops. External thermal loops are called heating loops. These loops interface with the body-mounted radiators which contain ammonia heat pipes.
Can someone please confirm that the current day Soyuz spacecraft uses water/glycol for cooling? Or if not, what is used today?
Mission Controllers Assess Soyuz Coolant LeakGround teams at Mission Control in Moscow continue to assess a coolant leak detected from the aft end of the Soyuz MS-22 spacecraft docked to the International Space Station. As a result, the planned Dec.14 Roscosmos spacewalk was canceled to allow time to evaluate the fluid and potential impacts to the integrity of the Soyuz spacecraft.NASA and Roscosmos will continue to work together to determine the next course of action following the ongoing analysis. The crew members aboard the space station are safe, and were not in any danger during the leak.The Soyuz MS-22 spacecraft carried NASA astronaut Frank Rubio and Roscosmos cosmonauts Sergey Prokopyev and Dmitri Petelin into space after launching from the Baikonur Cosmodrome in Kazakhstan on Sept. 21.Learn more about station activities by following the space station blog, @space_station and @ISS_Research on Twitter, as well as the ISS Facebook and ISS Instagram accounts.Get weekly video highlights at: http://jscfeatures.jsc.nasa.gov/videoupdate/Get the latest from NASA delivered every week. Subscribe here: www.nasa.gov/subscribeAuthor Mark GarciaPosted on December 15, 2022Categories Expedition 68Tags Canadian Space Agency, European Space Agency, International Space Station, Japan Aerospace Exploration Agency, JAXA, NASA, Roscosmos, Soyuz
The European robotic arm controlled by cosmonaut Anna Kikina surveys the Soyuz MS-22 crew ship after the detection of a leak that cancelled Wednesday’s spacewalk. Credit: NASA TV
Quote from: dawei on 12/15/2022 08:36 amCan someone please confirm that the current day Soyuz spacecraft uses water/glycol for cooling? Or if not, what is used today?Katya Pavluschenko is reporting Isooctane:https://twitter.com/katlinegrey/status/1603319799903551488
Quote from: eeergo on 12/15/2022 08:54 amQuote from: dawei on 12/15/2022 08:36 amCan someone please confirm that the current day Soyuz spacecraft uses water/glycol for cooling? Or if not, what is used today?Katya Pavluschenko is reporting Isooctane:https://twitter.com/katlinegrey/status/1603319799903551488From the quoted article it is not entirely clear what is used: either LZ-T2-K (isooctane-based) or PMS-1,5R (described as an organosilicon compound) (its chemical formula is on p. 94 of the article). The disadvantage of LZ-T2-K is that it is highly flammable (flash point of -9°C), which is why they started looking for alternatives. PMS-1,5R was introduced in the external loop of the Mir space station and is also used in the external loop of the Russian ISS modules. As for Soyuz and Progress, the article says: "LZ-T2-K and PMS-1,5R are interchangeable and used in the thermal control system of Soyuz and Progress". So not clear which if the two is used on Soyuz MS-22.
The official statement of Roscosmos: https://t.me/roscosmos_gk/7875
According to preliminary information, on Thursday, December 15, there was damage to the outer skin of the instrument and assembly compartment of the Soyuz MS-22 manned spacecraft. The crew reported that the warning device of the ship's diagnostic system went off, indicating a pressure drop in the cooling system. A visual inspection confirmed the leak, after which it was decided to interrupt the planned extravehicular activities by the crew members of the ISS Russian Segment Sergey Prokopiev and Dmitry Petelin. To establish the causes of the incident, Anna Kikina, using the camera on the manipulator installed on the Nauka module, photographed and filmed the outer surface of the ship. The data was transmitted to Earth, the specialists began to study the images. At the moment, all systems of the ISS and the ship are operating normally, the crew is safe. After analyzing the situation, a decision will be made on further actions of both specialists on Earth and members of the crew of the ISS Russian Segment. 7.9K viewsedited Dec 15 at 08:50
Quote from: B. Hendrickx on 12/15/2022 09:21 am[snip]As for Soyuz and Progress, the article says: "LZ-T2-K and PMS-1,5R are interchangeable and used in the thermal control system of Soyuz and Progress".Just below that they state: "Both coolants, not being electrolytes, have low corrosivity to all metallic materials used in STR KA. The PMS-1.5r coolant was used for the first time for filling the external circuits of the modules of the Mir orbital station. The PMS-1.5r coolant is used to fill the outer contours of the International Space Station and its modules."From which one can deduce it is not used on vehicles (probably because the risk is doesn't cumulate as much in exchangable craft compared to permanent modules).
[snip]As for Soyuz and Progress, the article says: "LZ-T2-K and PMS-1,5R are interchangeable and used in the thermal control system of Soyuz and Progress".
Quote from: eeergo on 12/15/2022 09:28 amQuote from: B. Hendrickx on 12/15/2022 09:21 am[snip]As for Soyuz and Progress, the article says: "LZ-T2-K and PMS-1,5R are interchangeable and used in the thermal control system of Soyuz and Progress".Just below that they state: "Both coolants, not being electrolytes, have low corrosivity to all metallic materials used in STR KA. The PMS-1.5r coolant was used for the first time for filling the external circuits of the modules of the Mir orbital station. The PMS-1.5r coolant is used to fill the outer contours of the International Space Station and its modules."From which one can deduce it is not used on vehicles (probably because the risk is doesn't cumulate as much in exchangable craft compared to permanent modules).It is very hard for me to get "[PMS-1,5R] is not used on vehicles" from "LZ-T2-K and PMS-1,5R are interchangeable and used in the thermal control system of Soyuz and Progress."Trying to use language instincts that imbue unspoken meaning when dealing with machine translated text is probably best avoided. For what it's worth, I take the second quote above as more general information about PMS-1.5r made stilted by the translation process.
Quote from: Twark_Main on 12/15/2022 04:28 amSome reports (eg Ars) are speculating that the coolant is ammonia, presumably because it is used in the US orbital segment external loop (the internal loop uses water).However note that the Russian designs have preferred to use silicone oil in the external loop (eg mentioned re:Mir on page 43, but AIUI the ROS currently uses it) and water/glycol for the internal loop (see page 7).While ammonia will evaporate harmlessly (as it has in previous ISS ammonia leak incidents), silicone oil would not. From page 20 of this document, there a description of the thermal control system on the Russian segment of the ISS, confirming the presumption that the ROS uses silicone oil in the external loop. Ammonia is mentioned as well.