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Europes Space Shuttle?


Uranium235

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It would be pretty cool if they could get it to work. The engine design is a leap forward (hybrid jet/rocket), so it would need a lot less fuel for the initial takeoff, and its reuseable. Might be a chance for the Esa to nab some business from the Russians who have the market in space travel pretty much cornered after the sad retirement of the shuttle.

http://www.bbc.co.uk/news/science-environment-27591432

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 the Russians who have the market in space travel pretty much cornered after the sad retirement of the shuttle.

I thought ESA was doing pretty well in the space launch business, as it is.

The Skylon thing has been talked about for decades (I recall a Tomorrows World programme describing it. That was back in Raymond Baxter's day), so if it was ever to "go", it would have done so by now. The story does keep coming back though - so maybe one day, if some gazzillionaire will finance it...

But so far as space shuttles go, it seems to me that if you're going to launch a 1,000 ton rocket to put 100 ton(ne)s into orbit, the best thing to do: given the cost, is to keep the payload in orbit. Not "waste" all that energy by bringing it back down again. :confused:  The shuttle never really achieved its goal of being a frequent (I think the plan was a 14 day turnaround) flyer and wasn't really that flexible in its use.

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pete_l, on 29 May 2014 - 8:47 PM, said:pete_l, on 29 May 2014 - 8:47 PM, said:

I thought ESA was doing pretty well in the space launch business, as it is.

Not as well as Roscosmos, who are also making a tidy packet from rocket engines and manned space flight. Point is, the technology needs to move forward if space exploration is to become a more economically viable activity - so I sincerely hope it works*

* But it may not be in my lifetime!

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. Point is, the technology needs to move forward if space exploration is to become a more economically viable activity - so I sincerely hope it works*

Yes, without a doubt.

When you look at aircraft development, it went from single seater biplanes to jumbo jets in the space of 60 years. ("helped" of course by some major conflicts with kicked the technology up several gears). When you consider that the rockets from 1961 are still basically the same as the ones flying today ... well :mad:

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Skylon has been around a long time now, been to a few talks about space vehicles and from what is said the idea is quite old. Friend from BAe talked of it some 30 years ago. Thing is so far nothing from it.

Mind you if you want to upset the presenter of the space vehicle talk just point out how similar the designs are to Fireball XL5, from Gerry Anderson et al back in the early 60's, especially the take off ramp. Skylon looks oddly similar. :eek: :eek: :eek: :eek:

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I think the very old idea you're thinking of was HOTOL, not Skylon which uses a different type of engine. I seem to remember the HOTOL was snapped up by the military and put under a secrecy blanket.

The launching ramp idea goes way back, as far as the VI if you like.

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It would be nice to see this fly  :smiley: although I think the virgin galactic ship and lifting body is the better idea. If they fitted the reaction engines to a VG type orbiter they could power the craft from mother craft release to max air breathing alt before swithching to rocket mode. The down side is the need for two vehicles.

 

 
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http://www.reactionengines.co.uk/space_skylon.html

Skylon was born out of the ashes of Hotol, which I understand they could never get to work before patience and funding ran out.

They seemed to have solved the frosting problem, and it passed some sort of tech demonstration study conducted by the ESA. It also has the support of David Willets, the science minister.

There's just the small matter of £10 billion to finance the project through to completion so necessarily they have to go slow as funding permits.

But the more I learn about this, the more excited I get. Would be brilliant for British high tech engineering and manufacturing if the first generation of cheap, re-useable reliable space transport is made here.

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The media is hyping this thing like no tomorrow, but when you dig into the detail there is so little to actually report.

There is no finalised engine design yet. That's not expected until 2017

They do have a working, proven-concept heat exchanger.

Look at the flight profile...it would be supersonic at a low altitude. Given that that killed off Concorde (at that went supersonic at high altitude) you have to wonder at this thing. If the concept is for a horizontal take-off, then where does the runway get built? You would have major issues with a flight plan that calls for 70 launches a year. Remember the row about Concorde and the issue of sonic booms over land? The answer probably includes plonking the massive runway somewhere in a very remote location (where would be suitable?). You'd probably aim for as near to the Equator as possible, but overflights would be a massive issue. What about abort modes and safe landing locations for those modes (SST used sites in Spain AFAIK for certain abort modes)? Then you'd have to consider the logistics of fuelling. H2 is tricky to transport.

The USA is the only country to successfully build a reusable space plane, though it never achieved anything near it's design brief (and cost over $200 billion. source: http://www.space.com/11358-nasa-space-s ... years.html ) We certainly can't finance something like that. Whether we are capable of building one is another matter. I would say that we aren't. We can't afford it, have no test program and very little history of space launches. We have no "prowess" in launch boosters.

What happens in the event of a single engine failure? Mounting engines off-centre on pylons is great until you have a failure. Look at the SR-71...managing engine flame-outs and thrust was a full-time, intensive task. An engine failure under full-thrust was almost always unrecoverable and resulted in the vehicle destruction.

There's so many unproven, complicated concepts in here that makes you wonder. Fuel-cooled flight surfaces for instance. The proven way to LEO is to use well tested, simple-as-possible tech, not layer upon layer of unproven concepts.

The overall economic concept is to be questioned too. The design offers a very limited payload of 12 tonnes to Low Earth Orbit at a cost of $2000-2700 per Kg. In comparison, Space X's Falcon Heavy will boost 53 tonnes to LEO at a cost of $1,500 to $2,350 per kilogram (source: http://www.thespacereview.com/article/1864/1). You can't beat economics like that. Cost. Cost. Cost. Rule 39 of Aiken's Laws of Spacecraft Design applies.....

They seemed to have solved the frosting problem, and it passed some sort of tech demonstration study conducted by the ESA. It also has the support of David Willets, the science minister.
 

I think that the report you are referring to was an ESA study into the technical feasibility. The ESA report makes for interesting reading. It is broadly optimistic and states "In conclusion the ESA assessment has identified a number of issues that must be addressed to increase the maturity of the vehicle and engine developments. However no impediments or critical items have been identified for either the SKYLON vehicle or the SABRE engine that are a block to further development. It is clear that the SABRE engine is critical for the successful development of the SKYLON vehicle"

It seems to me to be a classic British dream. A supremely clever guy (Alan Bond) coming up with a massive concept, but no realistic means to deliver. In the meantime, others are getting on with the business of actually doing things. SpaceX is the company to follow. What those guys are doing is magnificent.

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The USA is the only country to successfully build a reusable space plane,

The russians built and flew (once) the Buran spacecraft - but gave up after it's one, successful, flight.

That was a shame as it was actually more advanced than the scuttle - since it could, and did fly autonomously. Not just without a pilot on board, but it had a built in AI that made it's own decisions. I was told that when it came in to land, the onboard computers selected a flightpath that none of the people monitoring it had expected. They all thought it had made a mistake, but it turned out to be the better choice given the conditions.

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The russians built and flew (once) the Buran spacecraft - but gave up after it's one, successful, flight.

That was a shame as it was actually more advanced than the scuttle - since it could, and did fly autonomously. Not just without a pilot on board, but it had a built in AI that made it's own decisions. I was told that when it came in to land, the onboard computers selected a flightpath that none of the people monitoring it had expected. They all thought it had made a mistake, but it turned out to be the better choice given the conditions.

The Russian space program has always been based on minimising the input of the person in the craft.  Most of their craft have tried to be as automated as possible. History shows that the Russian program has, at times, been unbelievably callous with how they treat their cosmonauts and the disregard for risk. The Russian Lunar program is a case in point- they workload on the single cosmonaut would have been high, followed by a space-walk to get from the LK back to the command module. They exposed Tsibliyev to a ridiculous set of circumstances on MIR when they asked him to remotely dock a Progress with faulty, out-dated equipment.

In contrast, the Americans have always railed against the man being "Spam in the Can". Their craft have also been capable of automatic flight. The Apollo LMs were perfectly capable of automated cislunar navigation- in fact they were designed that way. The LMs were also capable of automated landings. It was probably much more to do with test-pilot egos that meant that every touch-down was done under semi-manual control. 

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Didn't ESA reject HOTOL development; seem to recall French derision of British concepts - VTOL jet aircraft and then HOTOL space rockets...

Who knows? They probably rejected it and accepted something that had a chance of actually getting off the ground! :grin:

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