Mikhail Kotov — about the reasons for the three attempts and the significance of the new Russian heavy-class launch vehicle
On the eve of Cosmonautics Day, on April 11, the Russian Angara-A5 heavy-class launch vehicle made its first launch from the Vostochny cosmodrome. However, it was possible to realize this only on the third attempt. But the Orion upper stage was put into a reference orbit, then it separated from the third stage of the launch vehicle and delivered the Gagarinets small satellite, developed by a private company, to low Earth orbit. After that, a mock-up of the payload was placed into geostationary orbit.
Why is so much attention focused on this rocket and what does the launch of Angara mean for Russian cosmonautics?
Output to the equator
A heavy—class rocket is one of the most important links in modern cosmonautics. Its main task is to launch spacecraft into high—energy orbits, such as geosynchronous and their special case is geostationary (altitude 35,786 km from the surface of the globe near the equator).
The speed of the spacecraft on the latter is synchronized with the speed of rotation of the Earth, and for an observer on the planet, the satellites are in the same place all the time. Therefore, the geostationary orbit is a convenient place for the location of a wide variety of communication satellites: communication, broadcasting devices, signal repeaters, etc. As a rule, these are large space mechanisms, for example, most of the Russian geostationary telecommunications satellites "Express" weigh about 2 thousand kg. With the help of a light or medium-class rocket, such a mass cannot be delivered to a geostationary orbit.
In the USSR, and later in Russia, this work was traditionally performed by Proton heavy-class launch vehicles, then Proton-M. So, they delivered into geostationary orbit, in addition to communication satellites, and meteorological satellites of the Electro-L series, with their help they built orbital stations — first Salyuty, then Mir and the Russian segment of the International Space Station (ISS). In addition, heavy-class rockets are used for interplanetary missions such as ExoMars (2016) and the launch of the Spektr-RG X-ray observatory.
The transition period
Protons have been working regularly for the Russian cosmonautics since 1965, with their help almost 400 launches were made. All the main launch sites for this rocket are located at the Baikonur cosmodrome in Kazakhstan. In total, two of them were made — No. 81 and No. 200. At the same time, there are two launch positions on each site — the right and the left. Currently, PU No. 39 (the left two-hundredth site) is mainly used.
However, the Baikonur cosmodrome is still located on the territory of another state — Kazakhstan. This is a matter of national security. We started working on it quite a long time ago. The simplest option is to create a launch pad for heavy—class launch vehicles on the territory of Russia itself.
"Protons", in turn, are obsolete. The main reason is toxic fuel vapor. Asymmetric dimethylhydrazine (aka heptyl) is used as fuel, and nitrogen tetraoxide is used as an oxidizer — both substances are dangerous to humans and the environment. Therefore, it was decided to gradually switch to a new Russian heavy missile, the Angara.
A multi-module approach
Angara is the first family of modern environmentally friendly launch vehicles created in Russia after 1991. Not a reworking or modification of an existing rocket (such as the Soyuz-2), but a completely created from scratch heavy launch vehicle. It is based on the idea of multimodularity: from two universal rocket modules URM-1 and URM-2, it is possible to assemble rockets of different classes — from light (Angara-1.2) to heavy (Angara-A5), capable of lifting, in particular, into low Earth orbit (LEO) payload from 3.5 thousand kg to 24.5 thousand kg, respectively. With a mass order on the same universal modules, in theory, it will be possible to reduce not only labor costs, but also the cost per UTM.
The heavy Angara-A5 is expected to be upgraded to the Angara-A5M version by boosting the engine of the first and second stages and lightening the design. This will make it possible to put up to 27.7 thousand kg into low Earth orbit. Subsequently, it is planned to create a version of the Angara-A5B. It will replace the third stage with oxygen-hydrogen, which will increase the load capacity to 38 thousand kg. Thus, Angara-A5V will bypass Proton-M by one and a half times, which outputs 23.7 thousand kg to LEO.
From two at once
Now Angara already has two launch sites in Russia. The first is at the Plesetsk cosmodrome (from where several launches have already been made), the second is at the Vostochny cosmodrome (from where the first launch was made on April 11). Why two at once? It's about the tasks.
Plesetsk is located in the Arkhangelsk region, which is a fairly northern region — from there it is energetically more profitable to launch spacecraft into polar and near-polar orbits. From the southern (by the standards of the Russian territory) "Eastern", which is located in the Amur region, it is more efficient to put satellites into geostationary orbits.
Cable refueling towers (KZB) are used at both sites to prepare for launch. These are stationary structures equipped with elevators and ladders for lifting maintenance personnel to work sites, as well as emergency evacuation equipment for personnel and special boxes for laying their own and transit pipelines and cables (going into the rocket through on-board connectors). One such tower is enough for a whole family of Angara missiles — from light to heavy. This eliminates the need to have several different sites with the current volume of work and launches.
It is planned that another "floor" will be added at the Vostochny cosmodrome later — to service manned launches. According to the head of Roscosmos, Yuri Borisov, after a successful launch on April 11, the first manned launch of the Angara is expected to be carried out in 2028.
Causes and prospects
Now Angara is still undergoing flight design tests, there are several launches left before its completion.
So, the launch of Angara-A5 was supposed to take place on April 9, but it was postponed twice to a reserve date — it was postponed for 24 hours for technical reasons. At first, the automation interrupted the preparation 2.5 minutes before the start. The reason is a malfunction in the pressurization system of the oxidizer tank of the central unit. This is a software error that does not require any serious improvements and changes, so a second launch attempt took place a day later.
On April 10, the actions to launch Angara-A5 managed to move even further. However, a new technical problem has been identified, related, according to the results of a preliminary analysis of telemetry, to a malfunction in the engine start control system. It was also promptly corrected, and on April 11, the snow-white Angara A5 nevertheless broke away from the launch table. This launch was successful.
Mistakes and postponements are the norm for the global space industry. Often, the automatic system is reinsured, saving from possible problems at launch, especially during the first flight tests from a new launch complex.
Nevertheless, you should not expect a quick transition to this rocket. First, you need to "shoot off" all the remaining "Protons" — there are about 10 versions of M left. So you can still have time to follow the "workhorse" going down in history. But the ROS national orbital station will obviously be built with the help of Angara.
