A Better Path Forward For Russian Space Launch -- Part 1: A Retrospective

The storied Soyuz and the venerable Proton...

For about six decades, they have been the mainstay of Soviet and Russian space launch. Together they have flown over 2000 times and supported almost every significant Soviet & Russian space mission from the beginning, including the entirety of their human spaceflight programs, if we count Soyuz's R-7 family predecessors.

They have been prolific, effective, and affordable. And yet for at least four decades, their replacements have been, with starts and stops, under development. They are, after all, quite long in the tooth. But how do you successfully replace such effective launch vehicles?

Zenit 3F   Credit: Roskosmos

The Zenit rocket family, which was intended to eventually replace both, first flew in 1985. It was sized between the smaller Soyuz and the larger Proton. It used more efficient engines than both and mostly non-toxic propellants, unlike Proton. But after the dissolution of the Soviet Union, it remained in Ukraine, so Russia could not rely on it. Since 1985, it has racked up a total of 84 launches, while Soyuz and Proton have flown far more times.

After the break up of the USSR, Russia got working on the Angara family. This modular launch vehicle was supposed to come in a range of configurations suited from medium to heavy launch. Economic constraints slowed down development, such that in the 30 years after it was conceived, it has only had 4 test launches. It is finally looking like it is almost ready, though the last test launch a few days ago had a failure of its upper stage.

There are now two versions of Angara in development -- Angara 1.2, sized for small-medium launch with about half the payload capacity of Soyuz, and Angara A5, sized to comfortably replace the Proton.

Angara A5    Credit: Russian Ministry of Defense

The price tag for A5 launches was originally projected to be around $100M, more than Proton, but in 2019, the target price was lowered to $57M (comparable to the Proton) with a goal of hitting that by 2024 once the rocket goes into series production.

By comparison, Soyuz has a base price of around $35M, with an additional ~$15M for the optional Fregat upper stage used for high energy launches. Prices for Arianespace launches are higher.

Russia has also been working for a couple of decades on a larger and more modern replacement for the crewed Soyuz spacecraft. After the original Kliper lifting body concept lost its European backing, Roskosmos began work on a capsule design that was then called Federatsiya and later renamed Orel. Now slated to fly on Angara A5, Orel seems to be gradually making progress towards becoming flight-ready.

      Soyuz spacecraft                                                  Orel  Credit: Roskosmos

In the meantime, under pressure from market price reductions ushered in by SpaceX's partially reusable Falcon family, Roskosmos has announced a number of new launch vehicle concepts utilizing partial reuse, not to mention some very ambitious super-heavy launch vehicle concepts gearing for a second Moon race. How actively any of these are being developed is a question this Western observer cannot answer.

What I can talk about, though, is the value of developing a heavy-lift launch vehicle like the Angara A5 to replace the Proton, and that of trying to use the Orel/Angara combo to replace Soyuz/Soyuz.

Let's take a look at Russian launches over the past 10 years. I will include launches of Soyuz by Arianespace from Kourou and exclude the 4 Angara test flights that only launched dummy payloads. There were a total 240 operational launches in the 10 year span of 2012 through 2021, and here's how they break down by type of launch vehicle:

You may notice that I excluded Soyuz 2-1v from the Soyuz count. The 2-1v is a substantially different launch vehicle with a very different core stage and lacks Soyuz's boosters and payload capacity. I counted it under "Small Launch" instead, along with the retired-since-2019 Rokot and inactive-since-2014 Strela small launch vehicles (converted ICBMs).

A pretty clear trend from looking at this graph is that there has been a general increase in Soyuz launches along with a pretty steady decline in Proton launches from a peak of 11 in 2012 to a low of just 1 per year in the last two years.

This can be attributed in part to pricing pressure (in particular from SpaceX Falcon launchers) that has made Proton uncompetitive in the international market, and also likely in part to a general global shift away from geostationary satellites toward low Earth orbit satellites, which not only require far less delta v to launch but also tend to be smaller.

At this point it makes sense to wonder about the wisdom of investing in a similarly priced Proton replacement when the demand for Proton has gotten so low. But of course the project was started when the launch market looked very different, and what's done is done. That said, we can ask if Russia even needs a heavy lift launch vehicle.

Let's take a look at the place of Soyuz in past launches from another perspective -- not just what it launched, but what it could have launched.

The blue line shows the percentage of payloads launched by Soyuz, showing an increase from around 50% 10 years ago to around 90% in the last couple of years.

The red line shows the percentage that could have been launched by Soyuz, including those launched by smaller launchers and co-manifested Proton payloads that likely could have been broken up into multiple Soyuz launches. Payloads launchable by Soyuz show an increase from around 70% to nearly 100%.

The picture gets even more striking if we look at what could have been launched by Soyuz in conjunction with one, or in rare cases two, orbital tug(s). The baseline orbital tug in this case would be a craft full of storable propellants that would be launched to low Earth orbit by Soyuz before the primary payload. It would wait in orbit for the payload, then rendezvous with the payload and take it to its target orbit/trajectory (e.g. GTO/GEO/TMI). Soyuz's optional Fregat upper stage seems just about right for the job with some relatively modest upgrades to enable rendezvous and docking.

Here's how we might expect the performance of such a system to compare to Proton:

The 2xSoyuz curve is for 2 Soyuz launches with a single Fregat tug, expected to cost around $85M -- not that much more than probable Angara A5 pricing or that of low-cadence Proton launches w/ a 4th stage. With a GTO* payload of over 5000kg, this should be able to handle most historical high energy Proton launches. 3xSoyuz refers to 3 Soyuz launches with two Fregat tugs, expected to cost around $135M. Such a system matches the performance of Proton with the new and rarely used Blok DM-03 upper stage (most Proton launches use the Briz-M).

Of the 240 payloads in the past 10 years, all but 1 could have been launched by one or more Soyuz launches with the help of a tug. The one exception is Nauka -- a long-awaited ISS module international partners would have been happy to launch.

So Soyuz is just a tug away from being pretty much all they need. But is it the best way to go? For a few payloads per year, it would be somewhat more expensive on a marginal cost basis, but given the savings possible through the retirement of multiple other launch vehicles and the fixed costs associated with their production lines and ground infrastructure, this streamlining seems almost certain to provide large cost savings.

Cost aside, there are at least two more reasons to keep Angara: retaining aerospace capability and employment, and Orel.

I contend that Orel itself is not a worthwhile replacement for the Soyuz spacecraft -- that they'd be better off upgrading Soyuz. Orel is designed to be a lunar-capable crew capsule that can carry 4-6 cosmonauts depending on the mission. It is indeed an upgrade compared to the Soyuz spacecraft. But this upgrade comes with a price. It is substantially larger and will likely cost more to fly. I don't believe its capabilities are worth it at this point.

The seat count increase seems unlikely to be needed, since Russia is already in the habit of selling 1 or 2 of Soyuz's 3 seats to international astronauts or tourists, despite only having a few crew launches a year. In other words, they have more capacity than they need, unless they are counting on a big increase in tourist demand at Orel prices, which again seems unlikely given the prospective competitive landscape of the coming decades.

As for the Moon, the Soyuz spacecraft is nearly capable of lunar missions, as well, and has been included, with modest modifications, in multiple lunar mission proposals going all the way back to the 60s. In fact, because of its lower mass, it would dramatically reduce the burdens for a lunar mission architecture, where mass requirements are multiplied by the transfer vehicle needing to be flown an additional 4-5km/s beyond LEO.

This then brings us to wanting to keep the Russian aerospace industry fruitfully employed and moving forward with new designs instead of just maintaining old ones. I 100% support this goal. But I believe there are better projects for them to work on.

On the spacecraft side, Russia has ambitions to build tugs, space stations, and a lunar base -- all worthy projects that could benefit from (likely even need) the resources being poured into Orel.

On the launch vehicle side, I would like to see them pursue two specific projects that could pave a way forward into a future with dramatically lower launch prices and higher cadence -- vehicles that have the potential to be cheaper to fly than Soyuz while providing Proton-like capabilities.

I plan to cover these launch vehicle ideas in part 2.

*Note that going into GEO requires substantially larger plane change maneuvers when launching from high inclination sites like Vostochny and Baikonur, so GTO launches from there tend to include a partial inclination change & perigee raise maneuver to reduce the burden on the payload. This increases GTO delta v requirements by a few hundred m/s beyond the ~2.5km/s apogee raise needed from 200km altitude LEO.