Russian Space Program: News & Discussion #3

Scorpius wrote:

Yes, yes, of course. After all, before Elon, no one came up with the idea of creating reusable launch vehicles.

Well Russia has of course played with glider type designs for reusable stages, but I am not aware of any flyable prototypes. But a self powered landing using the stage's own engine and retractable landing gear is a SpaceX thing whether we like it or not (That is what the Amur is supposed to be too). It might not be as efficient as the glider concept but it is all we have right now. And I credit Musk for making it happen. Credit where it is due. I honestly don't get the treatment that guy gets around this forum. He may be an opportunistic oligarch but he invests in projects and gets things done. And as far as I am aware, he is not a russophobe or anything, is he?

Daniel_Admassu wrote:
Well Russia has of course played with glider type designs for reusable stages, but I am not aware of any flyable prototypes. But a self powered landing using the stage's own engine and retractable landing gear is a SpaceX thing whether we like it or not

They did not come up with it, such rockets have been a regular occurrence in media for atleast 50 years, take You only live twice or Tintin as examples.

(That is what the Amur is supposed to be too)

I hope not is is very inefficient and would only feed the pindo's and liberust's retarded delusions about Russians being copiers.

It might not be as efficient as the glider concept but it is all we have right now. And I credit Musk for making it happen. Credit where it is due. I honestly don't get the treatment that guy gets around this forum. He may be an opportunistic oligarch but he invests in projects and gets things done. And as far as I am aware, he is not a russophobe or anything, is he?

Because the filth in question is a deranged retard who gets credited as some form of omniscient genius in all scientific fields while probably not even being able to comprehend the basics of Newtonian physics.

Judging by the projects this moron supports, which somehow always manage to be neither grandiose nor practical I would be willing to bet you that a litteral monkey would do a better job given the same subsidies.

Scorpius wrote:
So they have already worked out all possible schemes for launching payloads into space, and conducted research in the field of reusable launch vehicles with completely different parameters. Including the landing of the first stages with the help of engines. In particular, methane engines designed for 25-fold use were developed. And all this was long before anyone heard about the existence of Elon Musk. Therefore, to say that Russian developments are "inspired" by SpaceX developments is nonsense. In reality, the process was rather the opposite.

I admit that I was not aware of the powered descent recovery design attempts by Russia or the SU. Was it a conceptual presentation thing or did it also have a technical design? I simply didn't know. I am aware of methane engine designs of the Soviets for second and third stages.

But as a concept people everywhere are bound to think of a solution (and one as obvious as vertical landing) at some point or another. Technical capacity, feasibility, risk or a myriad of other factors may inhibit them from developing prototypes. That would have been a whole new challenge.

My point was putting something to work should count for something. And the fact that Russia has just started on a technical solution (its own, I am sure) for this concept indeed seems Inspired by Ellon Musk's work. And that is not necessarily a bad thing.

Reusable has been an expensive failure so far... the US Space Shuttles were terribly inefficient and cost a fortune to operate and use... The Russian Mir programme was cheaper than the US space shuttle programme and was vastly more useful.

But a self powered landing using the stage's own engine and retractable landing gear is a SpaceX thing whether we like it or not

Powered craft with undercarriage that lands on its own... that was the US Space Shuttle and the Soviet Buran wasn't it?

Using wings and aerodynamic shape for air braking to land on a conventional runway is vastly more efficient and safer than a vertically landing rocket....

To actually become efficient they would need to reuse each rocket 40-50 times and they are not getting anywhere near that... it is a stupid idea pissing away billions of dollars... lots of people are getting very rich over this and the US taxpayer is getting screwed.

What Musk is doing is essentially what the west does regarding plastic recycling...

GarryB wrote:

Powered craft with undercarriage that lands on its own... that was the US Space Shuttle and the Soviet Buran wasn't it?

Using wings and aerodynamic shape for air braking to land on a conventional runway is vastly more efficient and safer than a vertically landing rocket....

The Shuttle and Buran didn't use powered descent, they were gliders. They may have energy stored on board for control purposes (operating aerodynamic controls surfaces, telemetry, extending landing gear and so on) but the flight itself was unpowered. An that indeed is the key to efficiency of gliders. The Buran however was also supposed to have turbojets for the atmospheric phase of its descent which would have given it much more control of the landing.

What I really don't buy is this notion that reusability is less efficient than the alternative. How come? Musk and the NASA suppliers before him may have made it so for obvious reasons. They sell you something as completely reusable and after the first trip they ask for a new rocket's worth to 'refurbish' the thing. That was what Honeywell/Rocketdyne were doing with Shuttle. I can't be sure what the SpaceX model would be for extortion.

That does not mean that ultimately reusable craft (even powered ones) won't be more efficient than discarded ones in the hands of someone else. Even hot parts of engines might one day become reusable with minimal overhaul.

I was just wondering. Would a booster with a few smaller engines at the top angled outwards like the ones on the Soyuz launch escape tower allow for the rocket to avoid flying back down trough its own hot fumes?

The-thing-next-door wrote:I was just wondering. Would a booster with a few smaller engines at the top angled outwards like the ones on the Soyuz launch escape tower allow for the rocket to avoid flying back down trough its own hot fumes?

The Soyuz emergency escape column is used to temporarily 'suspend' the manned module long enough to allow the rest of the stack to fall down and get far away. The landing then can proceed with the parachute deployed and final thrusters for touchdown. The column carries its own fuel. It is nowhere powerful enough to suspend and land the whole rocket. Theoretically you can have a powerful engine at the top to land a stage with the potential advantage of solving the 'balancing' problem of bottom engines. But the downside would be extra weight as the rocket will also need a bottom engine for liftoff in the first place. With computers doing the balancing work for most rockets however, it is a moot advantage.

Daniel_Admassu wrote:Theoretically you can have a powerful engine at the top to land a stage with the potential advantage of solving the 'balancing' problem of bottom engines. But the downside would be extra weight as the rocket will also need a bottom engine for liftoff in the first place. With computers doing the balancing work for most rockets however, it is a moot advantage.

You are forgetting that it would also prevent the booster from being damaged by its own fumes on decent.

kvs wrote:we will have hordes of Musk lemmings
bitch that vertical landings are superior and reflect higher levels of technology.

In the west snake oil is what passes for advanced technology.

You never hear about how superior Russia is in the fields of nuclear physics or radar technologies, only that Russia does not make cellphones. I would take the criticism of these retards as praise, after all in the west good design choices and efficiency are viewed as workarounds for thoes who are unable to manufacture overcomplicated crap.

kvs wrote:
Vertical descent is really an idiotic concept. Instead of using aerodynamics afforded by the thick layers of the atmosphere, we
have the pointless fighting of gravity which requires extra fuel to be carried up and then down. It also means burning out any
reusable engine twice as fast.

Granted aerodynamic reentry is more efficient than a powered one, there are a few things to consider:

1. Launching a rocket is not just about lifting power. It is also about keeping it upright. But this problem diminishes rapidly once the vehicle gains momentum in the particular direction and then changing direction will be the difficult task. But for the first few seconds of the liftoff, it had been a major engineering challenge which was tackled with side thrusters and then thrust gimballig. First analog and then digital control systems have been developed for the purpose. Soviet Union was a pioneer in that regard despite the early help the competition had from the German V2 team after the war.
With a descent flight the problem essentially reverses and the rocket becomes more and more unstable as it slows down. With the engine located at the bottom, thrust gimballing would be less straightforward. So this is an inherent downside of vertical landing.

2. The amount of fuel and engine thrust required for descent is far less than for liftoff not just because you would be carrying less load but also because you are not working against gravity as hard - as you want to descend, not ascend. But however little propellant it is, it has to be carried along during ascent and the weight problem becomes a compounded exponential problem as some more fuel is needed to carry this additional fuel and so on. By the way this is the core of the Tsikolovsky equation as he is the first to solve the required differential equations for ascent out of a diminishing gravity well.

3. Aerodynamic reentry will inevitably require additional hardware such as wings, folding mechanism, stabilizers and landing gear, while a vertical powered one will only require the latter. This additional gear also needs to be carried along with the associated compounded fuel problem discussed above.

4. Unpowered gliding is inherently a less controllable flight as it is constrained for trajectory and timing. It also depends a great deal on the weather condition. Unlike the Shuttle and Buran which can reenter at a suitable moment, separated rocket stages do not have such luxury.

Overall sophisticated control systems are rendering much of the previous avionics problems obsolete. In my opinion revisiting the reusable vehicle idea is worth the effort, whichever one a design team is comfortable with.

FWIW my view is that fly-back strap-ons (eg Baikal) are the optimum solution for reuseability & economics.  They have the advantage of returning the expensive components (ie the engines) in better condition by not having to fly thru their own rocket plume, and therefore avoid the expensive disassembly, inspection and refurb that SpaceX is currently forced to perform between flights (in similar fashion to NASA activities to return the shuttles to flight condition). Flight controls are simplified, being an extension of the now well-developed UAV technologies.

The flyback vehicle can be designed with a detachable propulsion stage so that on recovery the engine compartment is unbolted and piping/hydraulic/electrical connections are disconnected using graylock couplings, tubing fittings and electrical QCDCs.  The engine module goes into the engine shop for inspection and refurb as needed, while the rest of the vehicle goes back to the hangar for inspection, de-fuelling and return to the parts inventory. Engine compartments are returned to inventory once their refurb is complete and then re-integrated with a new flyback module once a mission has been assigned.

Naysayers (usually Muskian groupies) always shit on the concept and say that winged flyback boosters "don't scale" but that is nonsense.  While it is true that the lift-off mass will be higher (due to the necessity for deployable wings, flight control surfaces, air-breathing engine & fuel, undercarriage etc) that isn't a significant obstacle.  SRBs with inefficient and heavy solid fuel and casings are effective and have been used for decades by both NASA (shuttle) and the USAF military launchers (Titan III, IV) so why should extra mass of the strap-ons be an issue?  Their only job is to push the stack up through the lower atmosphere and gain altitude so the core and high-energy upper stage can work more efficiently. if they are heavy, so what?  Use more of them...

Regarding Amur, I see this vehicle as a Soyuz replacement, essentially the Soyuz 6 or Soyuz-LNG concepts, a new-architecture modern launcher that will capable of both expendable and re-useable operation.  Use of LNG as opposed to RP-1 kerosene will greatly reduce fuel costs and simplify engine refurb for a quicker return to sevice.  Given that SpaceX has been operating vertical descent rockets, and that China is going to have its own with the Long March 8, its sensible for Russia to have some capability in this regard.  Neglecting the technology entirely would be narrow-minded, and it may well have useful niche applications beyond commercial rocketry.

The Shuttle and Buran didn't use powered descent, they were gliders.

That is exactly right...

Claiming landing using rocket fuel is a good idea is like wanting to replace the parachute with jet packs... it is just insane and offers very few benefits, but plenty of pretty clear costs and problems.

The Buran however was also supposed to have turbojets for the atmospheric phase of its descent which would have given it much more control of the landing.

No. The Buran had turbojets fitted for landing practise without needing to launch an Energyia rocket... it was for testing landing and flight handling on the full sized aircraft.

Buran was only launched once and it was launched in auto pilot mode so no human has ever landed a Buran.

What I really don't buy is this notion that reusability is less efficient than the alternative. How come?

When you reuse a plastic bottle by buying water in a plastic bottle and then just refilling the bottle it makes sense... simple and essentially free... water from a tap...

The problem was that with the Space Shuttle you have millions of pieces that all interact and it has been up into space and back through the vibration and shuddering g force of launch and reentry... you essentially have to take the thing completely to pieces and inspect it very carefully before you top it up and use it again. Heat tiles needed to be replaced, and the engines taken to pieces and meticulously checked for cracks or damage... it took time and was expensive and parts had to be designed to last which make them more expensive.

The Buran didn't have the rocket engines the US space shuttle had so much less weight, much less inspection and problems because the rocket engines of the Energyia were destroyed with use... they were designed to be used once... not dozens of times.

Even the cost of recovering and panel beating the main central fuel tank for the US shuttle was expensive... and those solid rocket boosters it needed to get into space were terribly expensive too.

To be reusable they have to land safely... they are having trouble doing that.

Now you build a business model expecting to be able to reuse something dozens or more times and they keep getting destroyed with use... well of course the money side is not going to work properly...

That does not mean that ultimately reusable craft (even powered ones) won't be more efficient than discarded ones in the hands of someone else. Even hot parts of engines might one day become reusable with minimal overhaul.

One day. But for now it makes more sense to recover bits with wings and gliding than adding the weight of all the extra fuel it will take to land parts for reuse.

But the downside would be extra weight as the rocket will also need a bottom engine for liftoff in the first place. With computers doing the balancing work for most rockets however, it is a moot advantage.

The amount of fuel needed for each landing is going to be big anyway... that is why gliding was selected for the Shuttles and parachutes for almost everything else...

Vertical descent is really an idiotic concept.

It is like.... how can we make returning to earth much more complex and expensive and more likely to fail...

On the moon there is no atmosphere so there is no alternative but on earth and mars and venus etc it makes sense to use natural in place air breaking.

With a descent flight the problem essentially reverses and the rocket becomes more and more unstable as it slows down. With the engine located at the bottom, thrust gimballing would be less straightforward. So this is an inherent downside of vertical landing.

The traditional solution is to ditch the engines and fuel tanks and just land the capsule with parachutes which seems to work just fine...

2. The amount of fuel and engine thrust required for descent is far less than for liftoff not just because you would be carrying less load but also because you are not working against gravity as hard - as you want to descend, not ascend

Everything you land with you have to take with you when you take off... so to have 10 tons of fuel for landing you have to burn 100 tons of fuel to get into space with you. Parachutes and wings are much lighter and cheaper and simpler.

3. Aerodynamic reentry will inevitably require additional hardware such as wings, folding mechanism, stabilizers and landing gear, while a vertical powered one will only require the latter. This additional gear also needs to be carried along with the associated compounded fuel problem discussed above.

The weight of the wings and components is negligible... in fact if you are only a rocket going to the space station then you don't need a huge shuttle... just a small cheap capsule that can use aerodynamic braking and parachutes for landing.

4. Unpowered gliding is inherently a less controllable flight as it is constrained for trajectory and timing. It also depends a great deal on the weather condition. Unlike the Shuttle and Buran which can reenter at a suitable moment, separated rocket stages do not have such luxury.

Space shuttles were found to be ridiculously expensive to use as a mere space shuttle... ie take people to and from a space station. Soyuz was much more efficient and air braking and parachutes works just fine.

Overall sophisticated control systems are rendering much of the previous avionics problems obsolete. In my opinion revisiting the reusable vehicle idea is worth the effort, whichever one a design team is comfortable with.

Trying to take off and land with a rocket is asking for trouble... it is more expensive even if it works properly and it wont work properly.

kvs wrote:

This advance in rocket manufacturing economics suggests that detachable URM engine sections that can parachute back to the
surface may be the optimal solution. One would assume that the cost of the fuel tanks is less than the cost of either the RD-191
or RD-171 based on complexity. It is doubtful that the cost of the metal used for the tanks and shell are high.

The parachute option over land would involve the use of small retro-thrusters like the manned capsules.

This actually could be an even better idea. I am thinking huge chutes stowed at the two ends of the module with additional inflatable bag cocoons softening the landing. The problem with parachute descent is landing in the wild and helicopter recovery requirement. Do you think a purposed Mi-26 can handle an empty URM-1?

Regarding the propellant tanks, it is not just about the metal cylinders but also the associated lines, pumps, valves, sensors, wiring and all the man hours spent on their production and inspection. They might not be as expensive as the engines (Which I am not sure) but they constitute a large part of the cost. So recovering them intact would be great.

Adding retro thrusters for touchdown would over complicate the solution and defeat the purpose.

kvs wrote:
The parachute option over land would involve the use of small retro-thrusters like the manned capsules.    

I was just about to suggest the exact same thing. This method of deceleration has seen a wide variety of uses since the 1960's from Vostok-1 to the BMD's and mars probes.

The Zenit-based strap-ons for Energia and Buran were originally intended to be recoverable by parachute, and was to include landing gear for a horizontal touchdown.  They never got around to trialling the recovery option (mass simulators were fitted instead), but the intent was clearly there.

Big_Gazza wrote:
The Zenit-based strap-ons for Energia and Buran were originally intended to be recoverable by parachute, and was to include landing gear for a horizontal touchdown.  They never got around to trialling the recovery option (mass simulators were fitted instead), but the intent was clearly there.
......

Interesting. I have always (subconsciously) wondered what those bulges were on the side of the Energia strapons. Pity they didn't get to try them out.

The picture shows landing on an unpaved terrain. An inflatable bag would have served better in that case. That is my amateur opinion. If I am seeing things correctly, there seems to be a set of small thrusters on the sides, next to the rear landing gear.

This ofcourse was at the late years of the Soviet Union and probably cost overruns and budget issues have compelled the engineers to include some efficiency measures. Russia should also continue on that effort.

Regarding the propellant tanks, it is not just about the metal cylinders but also the associated lines, pumps, valves, sensors, wiring and all the man hours spent on their production and inspection. They might not be as expensive as the engines (Which I am not sure) but they constitute a large part of the cost. So recovering them intact would be great.

Making them as simple as possible and also single use makes rather more sense...

Adding retro thrusters for touchdown would over complicate the solution and defeat the purpose.

The VDV already land armoured vehicles using various parachute arrangements with inflated balloons under the vehicle that collapse like airbags to reduce impact speeds at the last second, but also have retro rockets fitted to the parachute cluster to fire as soon as a hanging sensor hits the ground meaning the parachutes don't need to be so big and the payload can come down slightly too fast so it gets down quicker and has less time to drift. When the sensor touches the ground the retro rockets fire dragging the payload in an upward direction reducing its fall speed and then the large gas bags under the vehicle hit the ground and then burst further slowing the descent at the last second to make landing more tolerable...

The Zenit-based strap-ons for Energia and Buran were originally intended to be recoverable by parachute, and was to include landing gear for a horizontal touchdown. They never got around to trialling the recovery option (mass simulators were fitted instead), but the intent was clearly there.

You mean Musk is a time traveller?

Interesting. I have always (subconsciously) wondered what those bulges were on the side of the Energia strapons. Pity they didn't get to try them out.

For test launching it was probably considered an unnecessary added complication, but if they were taking lots of flights to the moon surface then it would become worth an effort.

This ofcourse was at the late years of the Soviet Union and probably cost overruns and budget issues have compelled the engineers to include some efficiency measures. Russia should also continue on that effort.

Buran also had a crew escape capsule... would have saved the crew of Challenger, not so sure about the one on reentry though... might have been moving too fast...