Russia’s Angara rocket has conducted its first orbital launch on Tuesday morning, flying in its impressive heavy-lift Angara 5 configuration to carry a payload mass simulator into orbit. Liftoff from the Plesetsk Cosmodrome in Northwest Russia was on schedule at 08:57 local time (05:57 UTC).
Angara 5 Debut:
During that mission the Angara, operating in a special configuration designed to allow testing of the URM-1 and URM-2 stages developed for the new series of rockets, flew for 21 minutes before successfully reentering over the Kura Test Range in Eastern Russia – a site which Russia often uses as a target for missile tests.
Angara is the first new rocket to be developed by Russia since the fall of the Soviet Union.
Designed as a modular rocket, it is able to fly in several different configurations to suit payload needs. The configuration that was tested Tuesday was the Angara 5; the largest and most powerful member of the series currently planned.
It became the most powerful rocket launched by Russia – or the Soviet Union – since the second and final flight of the Energia rocket carried Buran into orbit in November 1988. The Angara 5 also becomes the largest rocket ever to launch from Plesetsk.
Developed by Khrunichev, the Angara family is centred around two stages, named the Universalniy Raketniy Modul – Universal Rocket Module, or URM. The URM-1 forms the first stage of all Angara configurations, with the larger versions using additional URM-1 stages as boosters.
The URM-2 is an upper stage used as the second stage of the larger vehicles, while the smaller Angara-1 variants make use of existing upper stages instead.
Two Angara-1 rockets have been designed; the Angara-1.1 uses a Briz-KM upper stage and payload fairing taken from the Rokot vehicle and would be used to launch small satellites. The Angara-1.2 uses instead the Blok-I stage from the Soyuz-2-1b, providing a greater payload capacity.
The Angara-3 and Angara-5 both use the URM-2 second stage, with the first stage augmented by two and four additional URM-1s respectively. An Angara-7 has been proposed with six URM-1s clustered around the core vehicle. At present, however, the only configurations Russia intends to operate are the Angara-1.2 and the Angara-5.
Each URM-1 is powered by a single RD-191M engine, which derives from the RD-170 series first used on the Zenit and Energia rockets. In total four URM-1s have flown prior to Tuesday’s launch; in addition to July’s test mission three modified stages were used on the Russo-Korean Naro-1 rocket which achieved one success and two failures between August 2009 and January 2013.
The second stage during Tuesday’s launch, the URM-2, is powered by an RD-0124A engine. This engine is a minor modification of the RD-0124 used on the Soyuz-2-1b and 2-1v, adapted to longer-duration burns.
The Angara 5 can fly in two-stage configuration for low Earth orbit missions, but for missions to higher orbits a third stage can be added. Three different upper stages are planned; the existing Briz-M and a Blok-DM stage – likely the DM-03M – as well as the proposed cryogenic KVTK. Tuesday’s launch used a Briz-M.
The Briz-M was first flown in 1999 and is used as the fourth stage of most Proton rockets – although a small number use Blok-DM stages instead.
The Angara launch marked the eighty-third flight for the stage, a total which includes two test missions boosted by Proton-K rockets and eighty launches atop Proton-M vehicles.
The Briz consists of a core module housing the engines and some fuel tanks, with an toroidal unit surrounding it which houses additional propellant tanks. The additional tank can be jettisoned once its fuel is depleted, reducing the mass of the rocket.
For smaller vehicles, such as the Rokot, a modified Briz stage has been developed. The Briz-KM, which has flown 22 times, omits the additional tank. A prototype version, the Briz-K, was also used for the first three Rokot launches – two of which were suborbital tests.
The Briz-KM stage was proposed for one of the Angara-1 configurations, however no launches of this variant are currently planned.
The Briz-M is powered by an S5.98M (14D30) engine, with four 11D458M vernier motors to help control the vehicle. Unlike the first two stages which are fuelled by paraffin (kerosene) and liquid oxygen, the Briz-M burns unsymmetrical dimethylhydrazine (UDMH), oxidised by dinitrogen tetroxide.
The Angara-5 is the largest rocket ever launched by Russia. However, the Soviet Union built and flew two much larger vehicles; the N1 during the late 1960s and early 1970s and the Energia in the mid-late 1980s. Between them these two rockets made six launches, five of which failed to achieve orbit.
The N1 was designed by Sergei Korolev for the Soviet lunar program during the 1960s; and was intended to carry a modified Soyuz spacecraft and the LK lunar lander into orbit around the Moon.
Relying upon propulsion systems far inferior to their American counterparts, the N1 featured 30 engines on the first stage and over forty in the vehicle as a whole. Four test flights were conducted between 1969 and 1972, all of which failed during first stage flight.
Following the fourth failure, long after the Soviet Union had lost the race to the Moon, development of the N1 was abandoned.
During the 1980s, Energia was developed to place heavy payloads, including the Buran spaceplane, into low Earth orbit.
A single-stage core vehicle augmented by four liquid-fuelled boosters – which became the first stage of the Zenit rocket – the Energia relied upon either an upper stage, or its payload acting as an upper stage, to place its cargo into orbit.
Its first launch carried Polyus, a prototype heavy military satellite. Although the Energia itself performed as expected, the launch was unsuccessful as Polyus – which had to perform its own insertion burn to complete the launch – had been misprogramed to perform a 360 degree turn instead of the necessary 180 degree turn and consequently fired its engines in the wrong orientation. The spacecraft failed to achieve orbit.
The second Energia launch successfully deployed the Buran spacecraft, a spaceplane similar in appearance to America’s Space Shuttle, on an unmanned test flight.
Despite a successful mission, with Buran orbiting the Earth twice before landing back at the Baikonur Cosmodrome, the program was cancelled for financial and political reasons following the collapse of the Soviet Union.
As a result, the Buran launch also marked the final flight of Energia.
The largest rocket currently in service with Russia is the Proton-M, which is mostly used to launch communications satellites into geostationary orbits.
Proton, which was developed during the 1960s, is an aging design and relies upon toxic hypergolic propellants. Angara-5 will eventually replace the Proton, which is scheduled for retirement around 2030.
Tuesday’s test flight did not carry a functional payload. Instead the rocket placed into orbit IPM, a demonstration payload simulating the mass of a communications satellite.
Although details of the payload’s planned trajectory were not been published, it is likely to be targeting either a near-geosynchronous orbit or a geosynchronous transfer orbit since these are the orbits operational missions will carry this type of satellite to.
The mission began with liftoff from Site 35/1 at the Plesetsk Cosmodrome. The Russians decided not to provide live coverage of the launch.
Construction of this pad, which was originally intended for the Zenit rocket, began in 1986.
Construction halted during the early 1990s, with parts of the uncompleted complex later being used to outfit Sea Launch’s Odyssey launch platform, however the pad was later selected for redevelopment as Angara’s launch complex at Plesetsk. The only previous launch from Site 35/1 was the Angara’s maiden flight in July.
Flying almost due East from Plesetsk, Angara’s core stage throttled down around 47 seconds after liftoff, remaining at partial thrust until booster separation, which was expected to occur three minutes and thirty four seconds into flight.
The core URM would have then burned for another minute and fifty one seconds, propelling the upper stages into space. The core stage would then separate, with second stage ignition occurring shortly afterwards. The payload fairing was expected to have separated about fifteen seconds into second stage flight.
The second stage was then expected to burn for a little over seven minutes, taking Angara close to orbital velocity. The Briz-M would then take over, inserting the payload into orbit during its first burn, before making a series of further burns to raise its orbit and reduce its inclination.
On a typical Proton mission the Briz-M would make three to five burns over a period of seven to nine hours – although shorter three-burn missions are now rare after they were found to increase the chances of the Briz-M suffering an engine failure.
The Briz-M portion of the Angara launch is likely to have followed a similar profile. Depending on the mass of the payload, Proton-M/Briz-M launches can place satellites directly into geosynchronous orbit or into a transfer orbit from which they would normally manoeuvre themselves.
It was later revealed this mission would involve four burns, with the flight concluding at 14:57 UTC.
Tuesday’s mission marked the first time a geosynchronous launch has been conducted from the Plesetsk Cosmodrome; all of Russia’s geosynchronous missions to date have been launched with Zenit, Proton or occasionally Soyuz rockets from Baikonur – while the Zenit and Soyuz have also flown geosynchronous missions from foreign sites.
The Angara launch was the eighty-seventh orbital launch attempt of 2014 and the thirty-fourth launch of a Russian or former-Soviet rocket this year.
Russia has three more launches planned before the end of the year, with Soyuz missions from Plesetsk and Baikonur scheduled and a commercial Proton launch planned from Baikonur.
Two Angara launches are planned for 2015, with the Angara-1.2 and 5 carrying their first functional payloads into orbit. Details of these missions remain unclear and these missions may slip into 2016 or even 2017.
(Images via the Buran Section in the L2 Russian section, including four recovered videos (in Russian – converted and digitalized) – with additional images via RSC Energia, Roscosmos and public domain)
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