Subj : Russia preparing for third and final Angara A5 demonstration mission To : All From : NasaSpaceFlight Date : Thu Dec 23 2021 22:00:04 Russia preparing for third and final Angara A5 demonstration mission Date: Thu, 23 Dec 2021 21:58:15 +0000 Description: Russia is scheduled to launch the third and final demonstration flight of the Angara A5 The post Russia preparing for third and final Angara A5 demonstration mission appeared first on NASASpaceFlight.com . FULL STORY ====================================================================== Russia is scheduled to launch the third and final demonstration flight of the Angara A5 rocket on Friday, December 24, at 15:00 UTC. Angara is being developed and built by the Khrunichev State Research and Production Space Center and is intended to replace several existing launch vehicles. Angara will attempt to place its 2,400 kg mass simulator in a near geostationary orbit (GEO) using a new Persei upper stage. After a few hours, the Persei upper stage will perform two burns to place the payload in a graveyard orbit, a few hundred kilometers above GEO. Development History To ensure Russias ability to conduct orbital launches without relying on the Baikonur Cosmodrome , the development of a new rocket began in 1992. The outcome was Angara , a fully Russian-designed and launched rocket, set to launch from the Plesetsk Cosmodrome . See Also Angara MGM-3 Updates Russian Forum Section L2 Russian Section Click here to Join L2 Several companies bid for the contract to build the new rocket, and in 1994, Khrunichev State Research and Production Space Center, who also developed the Russian Proton rocket, was selected. The initial design of Angara was to use a modified RD-170 engine on the first stage, and a liquid hydrogen and liquid oxygen powered upper stage. In 1997, the hydrolox upper stage had been replaced with a kerosene powered upper stage, and the RD-170 had been replaced with the brand new RD-191. Later in the year, Khrunichev received approval from the Russian government to proceed with the design. In 2008, NPO Energomash announced that the RD-191 had completed development and hot fire testing, making it ready for manufacturing and delivery to Khrunichev. In 2009, Khrunichev took delivery of the first complete Angara first stage, and in 2010, the Director-General of Khrunichev announced that Angara was on track for its first flight test in 2013. In 2014, 22 years after Angaras inception, the first launch took place on July 9 , as an Angara 1.2pp launched from Site 35/1 at the Plesetsk Cosmodrome. Later the same year, the first flight of the Angara A5, a heavy lift launch variant, launched from Plesetsk , carrying a MGM n1 mass simulator into a geostationary orbit (GEO). The next Angara flight would take place 6 years later, with an Angara A5 launching on December 14, 2020. Render of the Angara A5 configuration. (Credit: Mack Crawford for NSF/L2) Stage Breakdown Angara has a number of different configurations that can range between having 2 and 3 stages, depending on the mission requirements. The core of any Angara rocket is the Universal Rocket Module, or the URM-1. Angara 1.2 uses a single URM-1, while an Angara A5 uses five, with four URM-1s strapped around the center core as boosters. The URM-1 is powered by a single RD-191, burning liquid oxygen and kerosene. The second stage of Angara is the URM-2, and uses a RD-0124A, which is a derivative of the RD-0124 currently flying on the second stage of the Soyuz-2 rocket. The diameter of the URM-2 varies depending on what vehicle it flies on; Angara 1.2 is expected to use a 2.9 meter diameter URM-2 to maintain a consistent diameter throughout the vehicle, and Angara A5 uses a 3.6 meter diameter URM-2. Angara 1.2 wont use an third stage, and Angara A5 wont use one while delivering payloads to low earth orbit (LEO), but will use one when delivering payloads to higher energy orbits. "" - "" pic.twitter.com/uENNHi91Nv (@Rogozin) February 6, 2021 Angara A5 can use either the Persei, a modified Blok DM-03 upper stage, or a new cryogenic upper stage called the KVTK. The KVTK will use a LH2/LOX powered RD-0146D, and allow the A5 to lift two additional tons to GTO, for a total of 7,500 kg. Derived from the four chamber RD-170 designed for Energia, the RD-191 used on the first stage has been in development since 2001. The engine burns kerosene and liquid oxygen, producing 2.09 MN of thrust in a vacuum, and 1.92 MN of thrust at sea level, with a specific impulse of 337 seconds in a vacuum and 310.7 seconds at sea level. The second stage engine, the RD-0124A, consumes a mix of kerosene and liquid oxygen, produces 294.3 kN of thrust in a vacuum, and has a specific impulse of 359 seconds. Previous Launches The maiden flight of the Angara family was a suborbital test of the Angara 1.2pp configuration. The maiden flight was a unique configuration, used to test both the URM-1 and a 3.6 meter URM-2 ahead of Angara A5s first flight. The test ended with an intentional impact at the Kura test range in eastern Russia. Angaras second flight was the maiden flight of the Angara A5, and carried a mass simulator representing a Russian geostationary communications satellite, weighing 2,400 kg. Following a complete mission success, the payload, which was not designed to separate, was placed into a graveyard orbit by two burns of the Briz-M upper stage. Angara A5 lifts off from Plesetsk on its second demonstration mission in December 2020. (Credit: Roscosmos) Angaras third flight was identical to the second, with another mass simulator placed into a geostationary orbit, and then later placed into a graveyard orbit. Launch Profile At T-0, Angara A5 will light its five RD-191 engines and fly east from Plesetsk. 47 seconds into flight, the core URM-1 booster will throttle its RD-191 to 30% of its rated thrust, reducing stress on the vehicle and allowing the core booster to burn longer than the outboard boosters. The four side boosters will continue to burn at full thrust until three minutes and 34 seconds into flight, when they shut down and separate. At this point, the core stage will throttle up for another 111 seconds before it shuts down and separates from the second stage. Following stage separation, the second stage will light its RD-0124A engine and will burn for 14 seconds before the payload fairings deploy. Roughly seven minutes later, the second stage will shut down, and separate from the Persei third stage. After the second stage separates, Persei will light its engines to place the payload into an initial parking orbit at an altitude between 180 and 250 kilometers. Over the course of several hours, Persei will light its engines multiple times to place the payload in a geostationary transfer orbit, and then later to circularize the orbit at an altitude of roughly 36,000 km. The Persei upper stage and mass simulator are encapsulated in Angaras payload fairing. (Credit: Russian Ministry of Defense) After the payload reaches GEO, the Persei stage will light one final time to place itself and the mass simulator into a graveyard orbit, several hundred kilometers above GEO. At this point, the stage will depressurize its tanks to avoid any potential explosion in space. Angaras Future Following confirmation of mission success, Angara will have completed the three demonstration flights needed to enter operational status. There are three flights planned for Angara in 2022 two Angara 1.2 flights and a single Angara A5 flight. The next flight is scheduled for January, with an Angara 1.2 for the Russian Aerospace Forces, launching a radar satellite to a sun synchronous orbit. After that, Angara A5/Persei will launch again, scheduled for March, carrying a Russian Ekspress-AMU communications satellite to geostationary orbit. The final launch of the year is scheduled for July, with another Angara 1.2 launching a South Korean Earth observation satellite. KOMPSAT-6, also called Arirang-6, is a synthetic aperture radar satellite, and can provide images with a resolution power between 0.5 meters and 20 meters. (Lead photo: Angara A5 on the pad in Plestsk prior to its second demonstration mission in December 2020. Credit: Roscosmos) The post Russia preparing for third and final Angara A5 demonstration mission appeared first on NASASpaceFlight.com . ====================================================================== Link to news story: https://www.nasaspaceflight.com/2021/12/angara-mgm-3/ --- Mystic BBS v1.12 A47 (Linux/64) * Origin: tqwNet Science News (1337:1/100) .