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Angara-5 completes its second test launch Originally expected in 2016, the second test launch of the Angara-A5 rocket was to carry the vehicle's first operational spacecraft. However manufacturing problems delayed the mission until 2020 and left it with a 2.4-ton payload simulator, IPN, once again. The Vehicle No. 71752 finally lifted off successfully on the morning of December 14, 2020, nearly six years after the original flight of the Angara-5 variant.
The second Angara-5 flight at a glance:
Preparing for flight Even before the first Angara-5 rocket embarked on its maiden test mission in December 2014, the PO Polyot company in the Siberian town of Omsk was busy working on the second and third vehicles. During 2014, PO Polyot manufactured the propellant tanks and other structural components of Vehicle No. 71752 intended for the second launch and also started outfitting key sections of the rocket. In parallel, the company's Division No. 67 was welding the bulkheads of propellant tanks for the third rocket (Vehicle No. 71753), while Division No. 14 was manufacturing flanges. Similar work on Vehicle No. 71754 was planned for 2015. Due to delays with the production of some parts at PO Polyot itself and others to be delivered from subcontractors, in particular from KB Armatura, the overall progress was under great pressure. (726) As of the beginning of 2015, the second rocket was expected to leave the assembly line by November. (725) However, by mid 2016, the rocket was yet to be completed with its launch slipping to the middle of 2017. Mission plan for the second Angara-5 flight
Angara-A5 rocket with Briz-M upper stage. In mid-2014, the first deputy to Roskosmos head Aleksandr Ivanov told the Ekho Moskvy radio station that Angara-5 vehicles had already been ordered for launches of operational satellites scheduled in 2016 or 2017. In an interview with the ITAR-TASS news agency in August 2014, the head of GKNPTs Khrunichev Vladimir Nesterov said that during its second mission, Angara-5 would be carrying an operational payload, even though the launch vehicle would officially remain in flight testing phase until 2020. As was the case with the first launch, GKNPTs Khrunichev's marketing arm, International Launch Services, ILS, was expected to "sell" available payload onboard the rocket to a customer outside Russia at a discounted rate, given the risk involved. However these plans had to be dropped as the second mission's launch schedule became uncertain. By 2015, plans were made for the new rocket's second mission to launch the Angara-5/Block DM-03 variant carrying the Angosat communications satellite, which was previously slated for delivery by a Zenit rocket from the Sea Launch platform. Both, Block DM-03 and Angosat, were being developed at RKK Energia in Korolev near Moscow. Once again, that plan also had to be abandoned in the face of new production delays at the manufacturing plant in Omsk. Ultimately, the rocket was assigned to carry a payload simulator, officially identified as IPN, from Russian Imitator Poleznoi Nagruzki. It apparently consisted of a metal rod holding multiple ballast rings to achieve the necessary mass. Together with a conical adapter, the simulated payload had a mass of 2,406 kilograms in the second launch of Angara-5, reportedly still below the actual payload that the rocket would be able to deliver to the geostationary orbit. Still, the total specific impulse developed by the Angara-5/Briz-M system during its second mission would be enough for the delivery of a 2.4-ton payload to the geostationary orbit, apparently as required by the original technical assignment for the project from the Ministry of Defense. As in the previous mission, the cargo would remain attached to the Briz-M upper stage. The second Angara-5 takes shape in 2017 During the Moscow Air and Space Show, MAKS-2017, the newly appointed head of GKNPTs Khrunichev Aleksei Varochko promised that the second Angara-5 rocket would be shipped from its manufacturing plant in Omsk to Moscow on July 25, 2017. Varochko's statement quoted by the Interfax news agency appeared to indicate that one of the five URM-1 modules comprising Angara-5's first stage would be sent to TsNIIMash for disassembly and testing in order to certify the vehicle's manufacturing line in Omsk for serial production. This assurance was apparently required after the manufacturing problems had been found in the first vehicle produced in Omsk. According to Varochko, the second Angara-5 rocket would then be sent to Plesetsk in February or March 2018. In the meantime, the factory in Omsk was working on the components of the third and fourth Angara rockets, however their final assembly was apparently been held off until the newly established production process could be certified as sound. However, only on October 6, 2017, Roskosmos State Corporation suddenly announced that the components of the second Angara-5 rocket "had been continuing to arrive" at GKNPTs Khrunichev in Moscow. According to Roskosmos, a train which departed the factory in Omsk on October 6 carried the BB-3 side booster for the rocket's first stage and a similar stage intended for dynamic testing in order to confirm the readiness of the manufacturing plant in Omsk for serial production. The state corporation did not specify when other boosters had been or would be dispatched, but said that the final assembly of the second Angara-5 vehicle would be completed at GKNPTs Khrunichev in Moscow and that the rocket would be shipped to the Plesetsk launch site in 2018. Angara boosters undergo dynamic testing On Jan. 16, 2018, PO Polyot factory in Omsk shipped another pair of URM-1 modules to Moscow, including the BB-1 strap-on booster for the first stage and the core booster, serving as the second stage for the Angara-5 rocket. It was clear from the accompanying press release that BB-2 and BB-4 boosters were yet to be delivered to complete the four-booster first stage. According to Roskosmos, a prototype of the URM-1 delivered earlier had been undergoing testing at TsNIIMash at the time. The testing began at the end of 2017 and, as of January 24, 2018, the trials at TsNIIMash were expected to last for several more months, Roskosmos said. Photos released at the time showed the apparent arrival of the prototype booster at the dynamic testing facility in TsNIIMash on Nov. 29, 2017, and the same booster in vertical position on Jan. 24, 2018. In an interview with the Izvestiya daily published on January 17, Director General of GKNPTs Khrunichev, Aleksei Varochko said that the second Angara-5 rocket would be delivered to the Ministry of Defense in 2018. However Varochko did not specify the actual launch date and hinted that the company had still been looking for a commercial customer, which would agree to fly its payload during the second Angara-5 mission. It probably also meant that there was no military or other federal payload assigned to that launch. That fact was confirmed in the August 16 TASS interview with the Head of Roskosmos Dmitry Rogozin who hinted that the Ministry of Defense was yet to determine the payload and the upper stage for the second mission of the Angara-5 rocket, which was now expected in 2019. Second Angara-5 slips well into 2020 On September 18, 2018, a train, carrying the final URM-1 booster for the second Angara-A5 rocket, departed its production plant in Omsk for Moscow, where the rocket was to undergo final assembly and testing, Roskosmos State Corporation said. In the meantime, the vibration and strength tests of the URM-1 prototype at the TsNIIMash facility were successfully completed, according to Roskosmos. The State Corporation re-confirmed the scheduled launch of the second Angara-5 vehicle in 2019, but did not specify the exact date or the type of payload for the mission. However, after the expanded management meeting at GKNPTs Khrunichev on February 7, 2019, the company announced that the next launch of the Angara-A5 rocket had been scheduled for December of that year. On April 1, 2019, the head of GKNPTs Khrunichev Aleksei Varochko told the official Russian media that the payload for the second Angara-5 launch (still planned before the end of the year) would be selected in August. By September 2019, officials promised to roll out the second Angara-5 rocket in November, but its launch was now projected "before or after the new year." On December 7, 2019, a message posted on the Twitter account attributed to robot Fedor, but believed to be operated by the Roskosmos head, announced that the second Angara-5 rocket would be "transferred to customer" in the first quarter of 2020, with the possibility of the launch in the following quarter. The message essentially confirmed another lengthy delay of the mission. Moreover, the January 15, 2020, post on the same account added that the launch would take place "on the decision of the Ministry of Defense, most likely, in the Summer of 2020." On February 12, 2020, speaking to a group of Russian military veterans visiting GKNPTs Khrunichev, Varochko said that the second Angara-5 would be shipped to the launch site in March or April 2020. He also promised that the same train used to deliver the vehicle from Moscow to Plesetsk, will then return to Omsk to deliver the third Angara-5 rocket to Moscow for the completion of its assembly.
On April 16, 2020, Head of Roskosmos Dmitry Rogozin announced that the Angara-5 rocket had been undergoing tests at GKNPTs Khrunichev's checkout station and that there had been no issues with the vehicle. Rogozin promised to complete the testing before the end of the month and to transfer the rocket to the military in preparation for its shipment to Plesetsk launch site. He also published an undated image of the rocket's boosters apparently during their integrated electric tests. On June 18, 2020, RIA Novosti reported, quoting industry sources, that the second flight of the Angara-5 rocket was scheduled for November 3 of the same year. On July 16, 2020, Roskosmos announced that preparations for loading of the boosters for the second Angara-5 mission aboard a train for their delivery to Plesetsk had began at GKNPTs Khrunichev. The photo released with the announcement showed lifting of the URM-1 booster with a crane inside Khrunichev's assembly hall. Second Angara-5 returns to launch pad
The second Angara rocket shortly after its delivery to the launch pad on Nov. 17, 2020. The 23-car train carrying components of the second Angara-5 rocket left GKNPTs Khrunichev in Moscow for Plesetsk during the night from August 13 to August 14, 2020. By that time, its launch was still expected on November 3 of the same year. On August 23, 2020, Roskosmos announced that the Angara-5 rocket was being unloaded in Plesetsk in preparation for flight tests. According to the official TV of the Russian Ministry of Defense, the military acceptance service also began inspecting the vehicle. On October 3, 2020, TASS announced that the launch of the second Angara-5 rocket was scheduled for November 24 of that year, but around the middle of November, the liftoff was set for November 28, 2020, at 08:22 Moscow Time (12:22 a.m. EST). The rollout of the vehicle to the launch pad at Site 35 was planned for November 17. During a visit of the Russian Minister of Defense Sergei Shoigu to Plesetsk on November 17, the official Russian TV channels showed the Angara-5 vehicle on its transporter-erector next to its umbilical tower, apparently shortly after the rocket's delivery to the pad. In the following two days, at least one photo of the rocket standing vertically on the pad was circulated on the Internet. On November 20, Head of Roskosmos Dmitry Rogozin posted a photo of the Angara-5 on the pad with a caption saying that "only a few days left until the beginning of the Angara-A5 heavy-class vehicle flight tests." According to the Russian industry sources, after its original rollout to the pad, the fully assembled launch vehicle would undergo test fueling and defueling of its URM-1 and URM-2 boosters. The defueled rocket would then be lowered into horizontal position and rolled beyond the perimeter of the launch complex to a special outdoor area set up for fueling of the Briz-M upper stage. There, the low-pressure tanks of the Briz-M stage, BND RB, would be loaded with their toxic hypergolic propellant components. (All high-pressure tanks aboard Briz had been loaded with pressurized gases previously, inside its processing facility). After the completion of fueling operations with the Briz-M, the rocket would be returned to the launch complex and re-installed on the pad for final processing and fueling of main boosters with kerosene fuel and cryogenic liquid oxygen for the planned liftoff. On November 23, TASS reported that the launch had to be postponed for several days due to low insulation resistance between two units discovered during the tests on the launch pad. At the same time, an industry source familiar with the matter told RussianSpaceWeb.com that after the rollout of the rocket to the pad, personnel had encountered problems while connecting ground equipment to the vehicle ahead of fueling tests. According to another source, there was no telemetry flow from the rocket to ground control. However, specialists were able to upload the flight program in the control system of the launch vehicle and its upper stage. The decision was made to resolve the issue after the return of the rocket to the vehicle assembly building, pushing a possible launch date to December 4 or 5, at the earliest. According to industry sources, the test fueling of the rocket finally took place on November 25, but various issues could delay the launch to as late as December 11. That launch date was reportedly close to multiple warranties on the rocket's systems. It is typical for the Russian rocket industry to end the warranties by December 31 of a particular year, however according to one report, there were deadlines on this particular vehicle coming even a week earlier then the end of the year. Naturally, the delay of the mission beyond the warranty deadline might require a complex re-certification process which launch officials often want to avoid. The rocket was reportedly returned to the assembly building by November 29 and another meeting on the status of the mission was planned for November 30. Due to the scheduled mission of the Soyuz-2-1a rocket with Gonets-M satellites, whose ground track was passing in the proximity of the Angara launch pad in Plesetsk, it was decided to keep the 2L vehicle in the assembly building. After the successful launch of the Soyuz on December 3, the State Commission overseeing the Angara flight testing met on December 4 to approve the return of the Angara-5 2L vehicle to its launch pad. According to various reports, the officials considered December 11 and December 14 as potential launch dates for the second Angara-5 rocket. Ultimately, the liftoff was set for December 14, 2020, at 08:50 Moscow Time. The rocket was rolled out to the outdoor Briz-M fueling pad on December 7, where operations of loading the space tug's low-pressure tanks with propellant components had started and were scheduled to be completed on December 8, followed by the transfer of the rocket to the launch pad on December 9. Both operations reportedly went as planned, though official photos documenting the delivery of the rocket to the launch pad were dated December 10, 2020.
The Angara-5/Briz-M vehicle lifted off as scheduled on December 14, 2020, at 08:50:00.282 Moscow Time from Site 35 in Plesetsk. Moments later, the rocket disappeared in the overcast sky as the snow continued falling at the launch site. According to the Russian military, assets of the Titov Chief Test Center began tracking the vehicle at 08:53 Moscow Time. Shortly thereafter, the Ministry of Defense announced that the orbital section of the rocket including the Briz-M upper stage and the mass simulator had separated from the third stage of the launch vehicle 12 minutes after liftoff. The military also confirmed that the further orbital insertion would follow a typical flight profile with three maneuvers and four engine firings of the upper stage engine. According to Roskosmos, the separation of the Briz-M upper stage took place 12 minutes and 28 seconds after the liftoff. According to tracking sources, the parking and the initial transfer orbits reached by the Briz-M upper stage were well within the required parameters after the launch, as confirmed by both the telemetry from the space tug and the data from navigation satellites. After a slightly shorter-than-planned but expected third engine firing, Briz-M jettisoned its external tank at T+13,465 seconds in flight (12:34:24 Moscow Time). There was only insignificant deviation in altitude of the transfer orbit at that point. According to the 18 Space Control Squadron in the United States, the external tank was left in a 380 by 36,849-kilometer orbit with an inclination 60 degrees toward the Equator. The stage then began its fourth maneuver to enter the target orbit, circling the planet 1,107 kilometers higher than the geostationary altitude of 36,000 kilometers above the Earth's surface. (The orbital inclination of the mission was still expected to match the equatorial plane). The target altitude for the second Angara mission was chosen to ensure that even in case of a major deviation in Briz-M's arrival trajectory, the stage would end up well away from the heavy international satellite traffic in geostationary orbit. Additional measurements of orbital parameters were made after the vehicle re-entered the view of Russian ground stations near the end of the orbital insertion process 9 hours 9 minutes and 53 seconds after the launch, which was concluded with a simulation of the payload release. (No objects were actually separated from the Briz-M stage). The latest data showed that the orbital parameters of the target orbit were very close to planned. The upper stage completed its final maneuver slightly ahead of schedule, but the final trajectory measurements showed perfect parameters of the target orbit. Experts credited a new algorithm in the pre-launch calibration of the gyroscopic instruments aboard Briz-M for the space tug's accuracy. The Briz-M then performed two additional maneuvers to enter a burial orbit, followed by the deactivation of its systems 12 hours 48 seconds and 58 seconds after liftoff from Plesetsk. Before and after the first maneuver to reach the disposal orbit, ground control conducted radio-measurements of Briz-M's orbital parameters. Once again, minor deviations in the orbital period and eccentricity were found to be well below average statistics accumulated during previous Briz-M flights and well within the requirements for the mission. According to 18 Space Control Squadron in the United States, the Briz-M and its cargo was tracked in a 36,923 by 37,595-kilometer orbit with an inclination 0.1 degrees toward the Equator. (The inert stage was 1,137 by 1,809 kilometers above the heavily populated geostationary orbit.) Planned launch timeline of the Angara-5 rocket launch on Dec. 14, 2020:
Known components of the Angara-5 rocket during its second launch:
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