Russian Space Program: News & Discussion #4

I am more excited about the costs of the Irkut and even smaller methane rocket than Amur.

For some context, 500 kg range to LEO is quite useful.

https://en.wikipedia.org/wiki/SCISAT-1

A Fourier transform spectrometer atmospheric composition measuring satellite with a mass of 260 kg.

VTOL is moronic.   The payload is reduced to carry fuel up and then down for vertical landing.   Gliding empty boosters down to the surface
like the Space Shuttle makes vastly more sense.    Imagine if they made the Shuttle VTOL.   It would never have been put into service.

Another waste of resources from VTOL is extended use of the rocket motors.   If you are going to save money by reusing them, then
why cut down their useful life by 50%?

Well another interesting aspect... imagine a first stage that is not a rocket.... but an air breathing scramjet... instead of the first stage full of fuel and oxygen, you could make it quarter the weight and size and scoop up air as it climbs... rockets that go into orbit don't just go straight up into space... they climb initially vertically and then roll over on their side and accelerate to orbital speeds and climb out of the atmosphere... the portion when the main rocket... which is also the biggest and heaviest because it has to carry everything up off the ground from a standing start... an air dropped rocket with a scramjet first stage that is started at say 10km altitude and mach 0.7 from some sort of transport type could launch horizontally and those wings could support it as it accelerates as well as recover that section after separation... it might climb to 40km altitude and be moving a mach 15 or more... you could make it very big and very powerful... and reuse it...

GarryB wrote:Well another interesting aspect... imagine a first stage that is not a rocket.... but an air breathing scramjet... instead of the first stage full of fuel and oxygen, you could make it quarter the weight and size and scoop up air as it climbs... rockets that go into orbit don't just go straight up into space... they climb initially vertically and then roll over on their side and accelerate to orbital speeds and climb out of the atmosphere... the portion when the main rocket... which is also the biggest and heaviest because it has to carry everything up off the ground from a standing start... an air dropped rocket with a scramjet first stage that is started at say 10km altitude and mach 0.7 from some sort of transport type could launch horizontally and those wings could support it as it accelerates as well as recover that section after separation... it might climb to 40km altitude and be moving a mach 15 or more... you could make it very big and very powerful... and reuse it...

Scramjets always need a 1st stage therefore they are only used as 2nd stage engines. Perhaps detonation engines because they currently have been tested for smaller sizes. Sadly we dont know the size of Irkut but its weight but the Amur is 360 tons while the re-usable Irkut is 25 tons.

GarryB wrote:Well another interesting aspect... imagine a first stage that is not a rocket.... but an air breathing scramjet... instead of the first stage full of fuel and oxygen, you could make it quarter the weight and size and scoop up air as it climbs... rockets that go into orbit don't just go straight up into space... they climb initially vertically and then roll over on their side and accelerate to orbital speeds and climb out of the atmosphere... the portion when the main rocket... which is also the biggest and heaviest because it has to carry everything up off the ground from a standing start... an air dropped rocket with a scramjet first stage that is started at say 10km altitude and mach 0.7 from some sort of transport type could launch horizontally and those wings could support it as it accelerates as well as recover that section after separation... it might climb to 40km altitude and be moving a mach 15 or more... you could make it very big and very powerful... and reuse it...

The idea is a good one, but as posted by gopnik not currently viable for the engines suggested.

But indeed, why not use the oxygen in the atmosphere to power lift off in lower layers of the atmosphere. So we reduce the
first stage to just the base fuel without carrying the oxidant. But the reason for carrying the oxidant is that it can be supplied
to the rocket motors in quantities vastly larger than can be drawn locally from the air.

It then makes more sense to have the first stage be winged stage that lifts off from a runway and carries the upper stages
mounted on top (e.g. Mriya-Buran). This achieves the total reusability of the first stage. But it limits the size of the upper
stages. So the concept can be applied to small payloads and we already have something like this with air launched LEO insertion
rockets.

A scramjet engine typically has a large central cavity where airflow and fuel is burned that on weapons like the rocket ramjet powered Kh-31 and SA-6 missiles use a solid rocket motor that falls away when consumed after accelerating the missile to a suitable speed where the ramjet can be started.

Having multiple first stages in a cluster all with solid rocket cores that start it moving, or perhaps a mix of solid rocket boosters and a core in the central man stage, where the outer rockets fall away after getting the entire rocket upwards and moving... would be options too.

Many rockets use multiple small boosters around its bottom first stage to maximise thrust for lift off to get the whole thing moving... there is no reason why they could not all be solid rocket scramjets with an initial high thrust solid rocket boost followed by scramjet acceleration using its weight efficiency to reduce overall weight which makes the requirement for super powerful rockets less of an issue.

Another issue of course is that more acceleration might take place in the thicker portions of the atmosphere which would require stronger heavier and more heat resistant upper stages.

However one of the reason for extreme high oxygen concentrations is to maximise thrust, but with air breathing engines it is not just oxygen that goes into the process... 70% of the "air" is inert nitrogen that is heated and used for thrust too, so in terms of volume you are getting more volume throughput for your engine and a scramjet motor can burn at supersonic airflows which was the primary advantage of rocket motors over jet motors in the past, but with scramjets that advantage is not so significant...

Big_Gazza wrote:Proposed mission profile for the 1st Zeus mission circa-2030. This has probably been posted previously but this the best version I've found.

FWIW there is some scuttlebutt that the mission might flyby Mars instead of Venus.  I hope not, as I find Venus to more interesting - Mars has been done a lot, while Venus has been comparatively ignored.

you have a bigger image or origin of it, i tried to translate it and I am sort of having difficulty if those are 3 of Jupiter's moons on the far right(only recognize callisto I believe for butchered translation of kalpisto)?

The other two moons are labelled as Io and Europa.

Nuland: I knew the evil Russians wanted to conquer Europe!

Nuland: **** Europe...