The probes of the solar system.

nokia69 wrote: »

none of this changes what I said

the US will only use the Russians while they develop new systems

If they hadn't thrown away all the previous systems they wouldn't have to. Also apart from SpaceX who are designing new stuff, the others who have flight proven sub components to use are spending a lot of time getting them working. I'm reminded that the US spent about $10Bn on studies for the Freedom Space Station that was originally meant to cost $8Bn to build.

If Boeing can deliver on time then the US will have spent 17 years depending on Soyuz for flights to the ISS.

nokia69 wrote: »

ULA are working on a new rocket to replace the Atlas and Delta

Blue Origin are working on a new rocket and on a new engine, they will fly something soon

Orbital Sciences are working on a new rocket

and NASA are working on the SLS

AFAIK there is more new work being done in the US than any other country

But most of the work in the US is re-inventing the wheel.

ULA are not working on a new rocket. They announced plans to start working on a new one a few months ago that will use a Blue Origin engine.

The new launch system, its booster stage powered by new engines made by Jeff Bezos' Blue Origin company, is meant to start flying in 2019 and cap a remaking of ULA as a more efficient organization.

The Blue Origin engine is being developed to reduce dependence on imported Russian engines.

Even if it is a US rocket that replaces all the "not invented here" tech that Atlas uses it's still not offering any new capabilities. The world isn't short of launchers of that size from India (sub orbital tests), Japan , China , ESA , Russia and Ukraine before you include the US offerings. Meanwhile Proton had it's 402nd launch recently. There's a lot to be said for using systems that have been debugged.

The first stage of Orbital Sciences old rocket is a pretty much a rebadged Zenit , and they've ordered a billion dollars of Russian RD-191 engines




SLS is a money pit. http://www.cbsnews.com/news/nasa-commits-to-heavy-lift-mega-rocket/

The SLS development program is projected to cost $7 billion from February 2014 through the rocket's maiden flight, a November 2018 test launch carrying an uncrewed Orion multi-purpose crew vehicle, or MPCV, on a three-week-long shakedown mission beyond the moon and back to an ocean-splashdown on Earth.

SpaceX are due to launch Falcon Heavy this year as they have paying customers lined up. It offers most of the capabilites of SLS but earlier and cheaper.

http://en.wikipedia.org/wiki/Energia#Energia_M Russian design for a 175 ton to LEO, just add more Zenit boosters to Energia.

IMHO launchers can be split into three stages.
The first stage.(punch through air and gravity drag, consider rocket sled / airplane as stage 0.5 ?) Big and dumb, cheap and reliable. There's no point in going to the nth degree trying to save weight or improve efficiency because fuel is cheap. The US is throwing way too much money at this non-problem. IIRC SpaceX spent something like $0.2m on fuel on it's barge test.

Second Stage(s) These get you into LEO OK now you can start to focus more on weight because each gram saved here means you can have a much lighter first stage. But reliability is critical which is why for some designs (Russian / early Atlas) you've had the engines on since launch instead of starting them in flight. Consider cryogenics here.

Third Stage. Now you are in LEO , if that's what you wanted job done. If not, you have plenty of time. What matters here most is total Delta-V. Thrust isn't that important unless it's reduce the total mass by needing less life support for humans or you are using the Orbeth Effect in a flyby. Unless you have a good reason not to you can use hall effect thrusters and other forms of solar powered electric propulsion. For a GEO satellite this means months getting to orbit but huge savings on station keeping mass too , depending on the mission for a planetary probe this could even translate to reducing first stage mass by half. But no, the US is throwing billions at the first two stages, when this is the place where savings really count (unless you are only going to LEO) and because a stable orbit means you have the luxury of time mad stuff like electric tethering or solar sails can be considered.

Cryogenic are really only of use for getting humans to escape velocity because you are back to the Hypergolics if you need longer term storage for manoeuvring or descending later on.


Flight of fancy for Mars. Hydrogen Peroxide has low energy density but it means oxygen and water , handy stuff to have around if you have an Apollo 13 on the way to Mars , though electrolysis and recycling of water is obviously the best way to get Oxygen on the trip.