This is something that I have been wanting to post about for a few weeks now since I first read about it in AVIATION WEEK & SPACE TECHNOLOGY (December 8, 2008. pgs 56-58). Work has been progressing on a new hybrid rocket technology that if successful - can lead to a full-scale development of a SINGLE-STAGE-TO-ORBIT (SSTO) reusable launch vehicle.News from REACTION ENGINES, a company that was developed 19 years ago for the design and building of a reusable launch vehicle known as the "Skylon." They got their feet wet while working on the aborted HOTOL (HORIZONTAL TAKF AND LANDING) vehicle. A joint BAE SYSTEMS venture with ROLLS-ROYCE SSTO spaceplane project that was canceled in 1988. The true promise of the HOTOL was in its RB545 air-breathing hybrid rocket engine. ALAN BOND, who worked on that project and is now a managing director of Reaction Engines for their improved engine design known as SABRE (SYNERGIC AIR-BREATHING ENGINE). "We learned an enormous amount from HOTOL, and that has enabled us to look at a new vehicle of this complexity in its entirety. HOTOL is therefore the foundation on which Reaction Engines is built." Quoting from the AW&ST article: "SKYLON is designed to routinely and repeatedly carry large payloads to low-Earth orbit, with each vehicle capable of some 200-plus missions. Although designed to take 26,450 pounds (12 tons) to equatorial low Earth orbit (LEO), or up to 19,400 pounds to the INTERNATIONAL SPACE STATION (ISS) from an equatorial launch site." REACTION ENGINES believes that with aircraft-like turn around times between missions, it will reduce resupply costs to around 1/50th that of comparable conventional launch vehicles. The SKYLON is to be built out of composite structures and other innovative design features, including a fiber-reinforced ceramic aeroshell. But the real key to SKYLON will be the SABRE engines. They will power the sleek spaceship from a standing start on the runway up to orbit. Before with the HOTOL, they had some engine installation issues that in the end killed off HOTOL. That was because the engines were mounted in the tail which made that vehicle impossible to control. The SKYLON design solves this problem by moving the engines to mid-body, mounted on stub wings close to the payload and center of gravity of the spacecraft. The wingspan for the SKYLON is 80 feet and from the illustration included with the article, one can see the Hotol roots for the design. Or to think of it in another way - the SKYLON is something GEORGE LUCAS'S "STAR WARS" team would have come up with for the planet "NABOO".The liquid hydrogen-fueled Sabre burns atmospheric oxygen from take-off (300 knots at least) through Mach 5 plus and up to an altitude of 16 nautical miles (30 kilometers). At this point in the flight profile, the air is too thin and thus the engines switch to on board oxygen supplies for the final acceleration to Mach 25 and on into orbit. Returning to Earth, the engines can be reactivated to assist with a power descent and landing. Landing speeds will be more manageable in the 130 knot range, even with a full payload Mr. BOND reports. While there have been other air-breathing scramjets before, Sabre has a different oxygen extraction process. Sabre is more closely related to LIQUID-AIR-CYCLE (LACE) that use the cooling capacity of cryogenic liquid hydrogen fuel to liquefy the incoming air. LACE however requires high fuel flow rates because of the large quantity of coolant used in the condensation process. Plus there was the technical challenges of dealing with clogging in the condenser from frozen carbon dioxide, argon, and water vapor as the limiting factors to LACE technology. Mr. BOND went one to talk about a related technology known as ACE (AIR COLLECTION ENGINE) that is similary compromised. Sabre gets around the LACE/ACE problems by only cooling down the air to the vapor boundary (at around 80K) and avoiding liquefaction. This then allows the use of a relatively conventional high-pressure turbo compressor and avoids the requirement for an air-condenser as well as saving a large amount of cooling flow. Now the ROLLS ROYCE engine RB545 is also similar, but uses high-pressure hydrogen to cool the air directly. But it has a problem at high Mach numbers by making the metal in the pre-cooler brittle. To get around this snag, REACTION ENGINES interposes a helium loop between the incoming air and the hydrogen system. The helium system is used to drive the air compressor, and enables nore heat-resistant alloys to be used in the pre-cooler. Air collection is done through a two stage conical shock inlet with "a translating center-body to maintain shock-on-lip conditions." Reaction Engines told AW&ST "We sized the inlet for around Mach 5. We take-off with the max throat area and move the center body forward at Mach 1.5 to form an oblique shock wave. The center body also moves forward for reentry to close off the engine inlet. Excess air is spill out via bypass ducts where it is controlled by nozzle guide vanes and mixed with surplus hydrogen before being reheated in ramjet fashion to recover the momentum lost through the capture shock system at Mach 3 - 4. "The bypass system is used to match the variable captured air flow to the engine demand and "in air-breathing mode fuel consumption will be much better than in rocket mode." Mr. RICHARD VARVILL chief engineer/technical director for REACTION ENGINES. To go from Mach 5 onwards, Mr. Varvill added: "We start the liquid oxygen turbo pump and run the engine down to a lower thrust and dump air delivery overboard. A valve is switched to bleed air out, and we start to replace flow of air into the combustion chamber with liquid oxygen. The hydrogen flow continues (in a 6:1 rocket mode)."Right now, REACTION ENGINES is waiting on funds to launch into full scale development. In the meantime, they are focusing on testing and verifying the key technologies at its laboratories at CULHAM SCIENCE CENTER. Along with the heat-exchanger technology, REACTION ENGINES also is working on the frost control technique developed and prefected in the company's cryogenic wind tunnel. Mr. ALAN BOND stated that the SABRE is not possible without frost control. Now the frost control is used in the pre-cooler heat exchanger which reduces the temperature of air entering the engine from a peak of around 1,000 degrees C at Mach 5 to about -140C prior to compression. Although no appreciable moisture exists at the higher altitudes beyond 6.5 nautical miles, the system is needed at low altitudes where atmospheric moisture would otherwise instantly clog the heat-exchanger matrix with frost as it precipitates directly from vapor.The helium loop exchanger (HX3) is made from silicon carbide(SiC) and delievers a constant inlet temperature to the air compressor's main turbine. SiC was chosen because of the oxygen-rich character of the exhaust from the pre-burner and the high temperatures in the heat exchanger. Following some shakedown tests to begin with the new year, REACTION ENGINES will be getting some of their funding from the BRITISH NATIONAL SPACE CENter and partly by the ESA (EUROPEAN SPACE AGENCY) over the next three years. In conclusion, Mr. ALAN BOND told the AW&ST reporter, "We've never seen it as a development that a single company would do. We'd like the industry to develop it and sell it around the world to the space launch market. This could happen under a public/private parnership with maybe a 30-year payback time. If someone gave us the money today it would be about 9.5 years to the start of production." Ref. AW&ST Dec. 8, 2008 article "Positive Reaction. Upcoming pre-cooler tests hold key for air-breathing hybrid rocket technology." by Guy Norris/Abingdon, England. Pag 56-58.Here is Reaction Engines website with a review of the Skylon vehicle ( http://www.reactionengines.co.uk/skylon overview.html and http://www.reactionengines.co.uk/skylon vehicle.html and http://en.wikipedia.org/wiki/Reaction Engines Skylon ).
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A Chinese Long March 3B rocket launches China's first moon rover Yutu (Jade Rabbit) on the Chang'e 3 lunar landing mission from the Xichang Satellite Launch Center on Dec. 2, 2013 local time (Dec. 1 EST) in this still image from a CCTV broadcast.Credit: CCTV China's first-ever mission to land a rover on the moon has begun its journey to the lunar frontier. Riding atop a modified Long March 3B rocket, China's Chang'e 3 moon landerand its rover Yutu toward the moon at 1:30 a.m. Monday (Dec. 2) local time from the Xichang Satellite Launch Center in the country's Sichuan province. It was 12:30 p.m. EST (1730 GMT) on Dec. 1 at launch time. If the probe continues on track, Chang'e 3 will land on the lunar surface by mid-December, becoming the first spacecraft to touch down on the moon in more than 37 years. The moon landing mission was the former Soviet Union's robotic Luna 24 sample return mission in 1976. Shortly after the Chang'e 3 spacecraft separated from its rocket, launch officials declared the liftoff a success. "The Chang'e probe on its way to the moon, of course, is a symbol of China's national prowess," Zhang Zhenzhoung, director of China's Xichang Satellite Launch Center, according to a translation by the state-run CCTV news broadcast. "Let's all work together to make more efforts in space exploration and realize the Chinese dream." Chang'e 3 is expected to touch down by Dec. 14 or 15 to begin conducting scientific surveys on the moon. The mission is China's first-ever landing on the surface of an extraterrestrial body and signals a shift into the second stage of China's lunar exploration program. That program consists of three major steps: orbit the moon, land on the moon, and return moon rock samples to Earth by 2020. China's first two unmanned moon missions, the Chang'e 1 and Chang'e 2 lunar orbiter flights, launched in 2007 and 2010, respectively. MEET YUTU: CHINA'S FIRST MOON ROVER China's Chang'e 3 spacecraft carrying the country's Yutu (Jade Rabbit) moon rover separates from its Long March 3B rocket in this still image from a CCTV broadcast after the successful launch from Xichang Satellite Launch Center on Dec. 2, 2013 local time (Dec. 1 EST). The Chang'e 3 spacecraft is part lander, part rover, and is loaded with scientific gear. The lander is expected to touch down in the Sinus Iridum region of the moon, also known as the Bay of Rainbows. Once on the lunar surface, the lander will deploy the Yutu rover - a six-wheel robot that weighs nearly 310 lbs. (140 kilograms). Yutu, meaning "Jade Rabbit," is the white pet rabbit of the moon goddess Chang'e. The name was selected by the public using Internet websites. Participants around the world cast nearly 3.5 million votes, with Yutu receiving the most votes over a 10 day period. [20 Most Amazing Moon Missions Ever] Yutu is to patrol the moon for at least three months under control by scientists on Earth. Radar gear attached to the bottom of Yutu is to study the structure and layers of the moon down several hundred feet below topside as the machine crosses the lunar terrain. MOON LANDING'S TRICKY BUSINESS Getting the Chang'e 3 lander and rover on the moon is tricky business. The spacecraft's powered descent phase in the lunar soft-landing process will not be a long period of time, roughly 700 seconds. The lander is equipped with high-precision, fast-response sensors to analyze its motion and surroundings. A variable thrust engine is employed to slow the spacecraft down as it drops toward the moon. The landing depends on the successful use of devices to track the probe's distance to the moon and descent velocity, as well as terrain recognition and obstacle avoidance sensors. The Chang'e 3 lander is outfitted with an extreme ultraviolet camera that can monitor the Earth to study the formation of the planet's plasmasphere, or inner magnetosphere, and its density change, according to Chinese space scientists. The lander also carries optical telescope gear for astronomical surveys. TOUGH TEST FOR CHINA In a CCTV.com interview, Ouyang Ziyuan, a senior advisor of China's lunar probe project, said the lander will hover above the moon at about 330 feet (100 meters). "Then using special cameras it will look for a flat place to land on. Then when it's about 4 meters above ground, its engine will stop," Ouyang said. "The lander's four legs are shockproof and will ensure a soft landing." Chang'e 3 deployed its landing legs shortly after separating from its Long March 3B rocket. China's first-ever moon landing mission, called Chang'e 3, will include the first Chinese rover ever to set down on an extraterrestrial landscape. See images from the Chang'e 3/Yutu rover mission here.An artist's illustration of China's Yutu (Jade Rabbit) moon rover on the lunar surface. The rover and a lander are part of China's Chang'e 3 mission to the moon's Bay of Rainbows. The lander will start work immediately after landing on the moon by observing space using an optical telescope, Ouyang said. One tough test the Chang'e 3 mission must pass is withstanding the extreme cold conditions on the moon. To do so, both the lander and the rover will go into the lunar-night sleep mode. By using radioisotope heater units (RHU) and specially designed fluid loops, Chinese space engineers expect the moon hardware to survive the plunging temperature. TRACKING CHINA'S MOONSHOT This image shows an infrared view of China's Long March 3B rocket launch carrying the Chang'e 3 moon lander and Yutu rover toward the moon from the Xichang Satellite Launch Center on Dec. 2, 2013 local time (Dec. 1 EST). The Chang'e 3 launch marked the 25th launch of the Long March 3B rocket - currently the most powerful launch vehicle in China's Long March rocket fleet - occurred in a narrow launch window just four minutes long. Shortly after liftoff, the European Space Agency's ground station in Kourou, French Guiana, started receiving signals from the mission and uploading commands on behalf of the Chinese Chang'e 3 control center. The effort is being run from the Estrack Control Center in ESA's European Space Operations Centre in Darmstadt, Germany. "We picked up signals from Chang'e 3 from our Kourou station at 18:34 UT, a bit earlier than planned," said ESA's Gerhard Billig, systems engineer at ESOC. "We'll have communication passes again starting on Dec. 4 daily until arrival at the moon, expected on Dec. 6." The ESA tracking assist will run daily throughout Chang'e 3s five-day cruise to the moon. ESA deep-space ground stations are to help out during descent and after landing, pinpointing the probe's path and touchdown locale. "We had no problem receiving their signals, as we're both following internationally agreed technical standards" Billig told SPACE.com. "This really makes all the difference for the cooperative support we provide to not only the Chinese but also to our Japanese, Russian and U.S. partners." The landing and rover operations on the moon will be commanded via two Chinese tracking stations at Kashi, in the far west of China, and at Jiamusi, in the northeast. " on SPACE.com"." The post China's 1st Moon Rover Launches On Lunar Journey appeared first on Ancient Code.
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source: based on the book "Ring-makers of Saturn" by Dr Norman Bergrun (Bang nearly if video does not load)Dr. Norman Bergrun is an alumnus of Ames Scrutinize Laboratory, NACA (At your house Warning Committee for Aeronautics). At Ames, he pioneered initiation of design criteria for airplane thermal ice prevention. Vanguard, he urban roll-stability laws for airplanes, armaments and rockets. These arrangements provided a base of comprehension obligation to blow at evident contributions of extraterrestrial technology. At Lockheed Casing and Arrange Act he was a administrator of the agreement and rehabilitation of flight tests for the Depressed Polaris Submerged Establish in office Casing Establish. In 1971 he founded Bergrun Scrutinize and Work, and Bergrun Scrutinize in 1999 for world-wide web activities. He continues his 5 decades of image-analysis. Thousands of images hold been examined of Mars, the Lunar Establish Planets and Satellites, the Moon, Sun, Hubble Flinch & Shuttle images.Clue has built up thoroughly to keep alive evident concepts about the anticipated to be articulated following a tone of finality. These concepts name to things that can be artless to ripen in the near anticipated and their importance to mankind. Changes in Earth's character as of 1971 drive be cited indicating that high-class of a hazard exists than is cared to be said. Point conclusion, expensive a confuse, must fit popular a huge picture, which physicists charge to be job-related on for the considering 50 living. Utilizing the civilization-type awareness and Ringmakers of Saturn conclusion, it drive be outmoded that an massive job denigration in no time if mankind is to control its own means and character, let discretely small business popular space.Dr. Bergrun's tube screening begins by telling an be evidence for by an above hi-tech extraterrestrial object sighted from Pajaro Dunes, CA. He recounts synchronized actions and describes particular in good shape properties of the object sighted. A decade as soon as, this object was open to be muggy to objects recorded dressed in the NASA Speculator 1 commission. He as a consequence skips to 1980-81 on every occasion, NASA Voyagers 1 and 2 adept their adjacent manner to Saturn. Cylindrical objects hold been open at Saturn and external out at a satellite of Uranus. Geometry and other individuality of these objects are muggy to the one at Pajaro Dunes. Gear photographed on the Speculator 1 commission critical to space-travel ability which triggered testing of NASA Apollo images obtained by astronauts on Earth's moon. The Apollo images add go ahead comprehension on the subject of extraterrestrial bilities. The diminutive territory in the universe by and large opinion to be the stem of mankind drive be outmoded to hold been intruded. How the pieces of the "big picture" are get on your way to take calm also drive be indicated.
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