Skylon: The New Shuttle

[Space Racer]

Skylon is a single-stage-to-orbit (SSTO) space plane that uses a convertible jet engine. The engine converts in flight from a conventional jet engine to a ramjet, somewhat similar to the SR-71 Blackbird, and then to a rocket engine. It burns hydrogen with air, then switches to hydrogen with liquid oxygen. The plane's fuselage is mostly comprised of two hydrogen storage tanks.

http://en.wikipedia.org/wiki/File:Skylon_diagram.jpg

The concept has been in development since the early 80's. The problem was that there was no efficient way to cool the intake air enough at high speeds to make combustion efficient. But now Reaction Engines Ltd. has developed a lightweight heat exchanger that uses 1mm tubes with 27-micron thick walls. It cools the incoming air from 1000*C to -150*C in 1/100 second, and it does it without creating frost on the tubes. (That's 1832*F cooled to -238*F.) Chilled helium transfers the heat to a nitrogen boiler in the test models. The nitrogen is replaced with liquid hydrogen in the Skylon jet.

The heat exchanger concept for jet engines has been in development since the 70's.

http://www.reactionengines.co.uk/heatex.html
http://www.reactionengines.co.uk/heatex_work.html

Videos:
http://vimeo.com/45136248
http://vimeo.com/45382870
http://vimeo.com/45371849

Other sources:
http://en.wikipedia.org/wiki/SSTO
http://en.wikipedia.org/wiki/SABRE_%28rocket_engine%29
http://en.wikipedia.org/wiki/SR71
http://www.bbc.co.uk/news/science-environment-17864782
http://en.wikipedia.org/wiki/Skylon_%28spacecraft%29

[Space Racer]

To be a little more precise, the engine is a rocket engine at the back end, surrounded by ramjets. The rocket engine is fed by a turbo-compressor, like a jet engine. Some of the excess hydrogen left over from cooling inlet air is burned in the ramjets.

[Six]

My old turbine teacher was a captain in the airforce and flew the SR-71 black bird.

We hounded him all semester for info on that plane.

He said he would swallow a pill before divulging sensitive information on the blackbird.
It was 40 years later still classified although he did show us a couple of really cool video's and let us in on some of the tech.

The leading edges of that aircraft got to temperatures of 800f at top speed and it dropped fuel like a colander on the tarmac until it got up to speed and the expansion of the panels finally caused the aircraft to seal up.

[timebuilder]

My old turbine teacher was a captain in the airforce and flew the SR-71 black bird.

We hounded him all semester for info on that plane.

He said he would swallow a pill before divulging sensitive information on the blackbird.
It was 40 years later still classified although he did show us a couple of really cool video's and let us in on some of the tech.

The leading edges of that aircraft got to temperatures of 800f at top speed and it dropped fuel like a colander on the tarmac until it got up to speed and the expansion of the panels finally caused the aircraft to seal up.

If memory serves, the plane grew almost two feet longer at flight temp.

[Six]

When I worked at Stewart and Stevensons in their AC test cell there was a 62 year old Russian that worked down in electrical that was in the soviet air force.

We used to get into pissing matches about who was best.

He brought up Gary Powers and I said what did you guys do about the Black Bird.

He said in his thick Russian accent " what could we do ?? " " we built mock installations with balloons "

He said even during the height of the cold war Russian soldiers idolized that plane.

[Space Racer]

The heat exchanger allows for the combination of lower operating temperatures, light weight materials, reduced oxidizer storage requirements, the use of low-drag wings for lift, and a high thrust-to-weight ratio at all speeds.

The designed thrust/weight ratio of SABRE ends is high—up to 14—compared to about 5 for conventional jet engines, and just 2 for scramjets.[4] This high performance is a combination of the cooled air being denser and hence requiring less compression, but more importantly, of the low air temperatures permitting lighter alloy to be used in much of the engine.
...
The losses from carrying the added weight of systems shut down during the closed cycle mode (namely the precooler and turbo-compressor) as well as the added weight of Skylon’s wings would appear to be heavy, yet the gains in overall efficiency more than make up for this. These losses are greatly offset by the different flight plan. Conventional launch vehicles such as the Space Shuttle usually start a launch by spending around a minute climbing almost vertically at relatively low speeds; this is inefficient, but optimal for pure-rocket vehicles. In contrast, the SABRE engine permits a much slower, shallower climb, air breathing and using wings to support the vehicle, giving far lower fuel usage before lighting the rockets to do the orbital insertion.

Advantages

Unlike traditional rocket engines, and like other types of air breathing jet engine, a hybrid jet engine can utilise air to create combustion saving on propellant weight and therefore increasing payload fraction.

Ramjets and Scramjets must spend a significant amount of time within the lower atmosphere to build speed to reach orbital velocity creating issues with extremely high drag leading to intense heating and the subsequent weight and complexity of required thermal protection. A hybrid jet like SABRE needs only reach low hypersonic speeds inside the lower atmosphere before engaging its closed cycle mode, whilst climbing, to build speed.

Unlike ramjet or scramjet engines the design is able to provide high thrust from zero speed up to Mach 5.5,[16] with excellent thrust over the entire flight, from the ground to very high altitude, with high efficiency throughout.

http://en.wikipedia.org/wiki/SABRE_%28rocket_engine%29

[Space Racer]

Reaction Engines: Major Advance Towards the Next Jet Engine

http://www.rocketeers.co.uk/node/2258

[Space Racer]

Europe’s Next-gen Rocket Design Competition Included Surprise Finalist

http://spacenews.com/launch/120713-e...-finalist.html

[Space Racer]

Turning the corner for investment:

http://www.parabolicarc.com/2012/10/...u-buck-rogers/

[Space Racer]

The Biggest Breakthrough in Propulsion Since the Jet Engine

http://www.reuters.com/article/2012/...8AR0V220121128
http://www.bbc.co.uk/news/science-environment-20510112
http://news.yahoo.com/factbox-sabre-...--finance.html

http://www.parabolicarc.com/2012/11/28/44703/
http://www.parabolicarc.com/2012/11/28/44686/
http://www.businessinsider.com/react...ooling-2012-11

[biodieselman]

I apologize for getting political but every time I hear "Hate America Firsters" say we are a fat, lazy, stupid people I think of the US first in Olympic medals & technology achievements that no other nation has yet to design such as the Blackbird & the Shuttle.

I remember long ago reading that the exotic futuristic shape of the Blackbird was designed to be purely functional. At the speeds & altitudes they expected to fly at, the air wasn't dense enough for the engines to operate at extreme altitudes. The shape of long nose was calculated to compress the air for the engine intake. What I didn't know was the inlet cones moved to allow flight from take off to high altitude super speeds.

You can read the whole thing with the link in the following quote.

...

The aircraft's designed performance envelope meant that the platform had to be viable in many different 'realms' of flight, from slow flight for takeoff and landing through transonic, supersonic and up to hypersonic (Mach 2 and over). The problems of aerodynamics involving the engines themselves took up a great deal of the project effort - in order to allow for supersonic airflow to enter the engines without extinguishing them, the airframe was designed so that the actual bowshock from the nose of the airplane (which normally interferes with engine flow as an aircraft approaches Mach 1) would impinge directly onto the inner surface of the engine nacelles. This allowed maximal 'feeding' of the huge engines. In order to prevent the shockwave from disrupting the airflow, the engine nacelles sported a pair of enormous conical 'inlet cones' that were to be moved independently of the main engine controls.
...

I thought the original design of the Blackbird was not to carry weapons & it's sole purpose was reconnaissance & simply to fly higher & faster than the speed of anti-aircraft missiles.

You'll also find this in the link above.

...
Useless trivia: This plane was originally designated the RS-71. RS stood for Reconnaissance/Strike. Technically, it could carry a single nuclear gravity bomb. However, when it was first publicly announced, President Lyndon Johnson referred to it mistakenly as the SR-71. Since they didn't want to contradict the President of the U.S.A., the Air Force quickly renamed it the SR-71.
...

When I see American Boeing & NASA designing the X-51 Wave Rider...

and private industry SpaceX here in Hawthorn California doing what most nations can't do...

it makes the old heart swell with pride in American's ability to designs technologies such as the above and the Skylon: The New Shuttle .

[Space Racer]

Yes, it sure is great that the US and Great Britain (where the jet engine and Sabre engine were invented) are able to continue to march with the old pioneer spirit after resting on our laurels and our haunches for so long. And it's very possible that US investors and companies will provide a substantial portion of the support and development that Skylon needs before it comes to fruition. (I think Alan Bond believes in the back of his mind that the US will be a necessary player if Skylon is to be born and put into service during his stewardship of Reaction Engines, or maybe during his lifetime.)