Showing posts with label Electric-Propulsion Test Stands. Show all posts
Showing posts with label Electric-Propulsion Test Stands. Show all posts

Tuesday, October 8, 2013

'SPACE' in News



Chinese Super-Heavy Launcher Designs Exceed Saturn V

Source: Source: Aviation Week & Space Technology
September 30, 2013 - Chinese engineers are proposing a Moon rocket more powerful than the Saturn V of the Apollo missions and matching the payload of NASA's planned Space Launch System (SLS) Block 2, the unfunded launcher that would put the U.S. back into super-heavy space lift.
Drawing up preliminary designs for the giant Long March 9 launcher, Chinese launch vehicle builder CALT has studied configurations remarkably similar to those that NASA considered in looking for the same capability: to lift 130 metric tons (287,000 lb.) to low Earth orbit (LEO). One of the two preferred Chinese proposals has a similar configuration to the design finally adopted for SLS Block 2, though the takeoff mass for both CALT concepts, 4,100-4,150 tons, is greater. On that measure, at least, China wants to build the largest space launcher in history.
Preliminary work is underway for the intended engines. At the Xian Space Propulsion Institute, engineers are certainly planning and probably doing risk-reduction work for a kerosene-fueled engine, apparently called YF-660, that would be comparable to the 690 tons thrust of the Saturn V's F-1. The Beijing Aerospace Propulsion Institute, meanwhile, is working on critical technologies for a 200-ton-thrust liquid-hydrogen engine that would be used for the first stage of one launcher design and for the second stage of both. That engine is apparently called the YF-220.
Comparison with current launchers and engines highlights the scale of China's ambitions: Whereas U.S. SLS engineers are aiming at a 10% increase on the throw weight of the Saturn V and would use mainly familiar propulsion technology, CALT's super-heavy launcher would have 10 times the throw weight of anything that China now has in service, and would be four times bigger than even the largest rocket it is developing—the Long March 5. The YF-660 engine would be five times as powerful as the biggest engine China has so far built, one that has not yet flown.
The Chinese industry is seeking permission to begin developing a Moon rocket. Studies encompass payloads as low as 70 tons to LEO, says an industry official, suggesting that China may follow the SLS concept by first building a smaller launcher adaptable to enlargement.

Possible Long March 9 configurations were shown two years ago. At the International Astronautical Congress held here Sept. 23-27, CALT published main specifications (see table). One of the two concepts, Scheme A, would have four YF-660s mounted in the core first stage and one in each of four side-mounted boosters. In Scheme B, most of the takeoff thrust would come from four solid-propellant boosters, each generating 1,000 tons of thrust, while four YF-220s would be mounted in the first stage. That adds up to 4,800 tons, but the specified total is 5,000 tons, suggesting that the solid-propellant booster engine, the YF-220 or both will generate a little more than the thrust attributed to each individually. The designation of the YF-220 may hint at its real thrust target. More

Vostochny Key To Moscow Missions To Moon, Mars

New Russian launch site aimed at curbing reliance on Baikonur.
The delayed September launch of a commercial Proton rocket is Russia's latest justification for ending reliance on the Baikonur Cosmodrome, the world's oldest and largest spaceport situated in the desert steppes of neighboring Kazakhstan.
Although Russia lofts many scientific and military spacecraft from Plesetsk Cosmodrome north of Moscow, commercial and government launches to geostationary orbit—the destination of most telecommunications satellites—can be conducted only from Baikonur, where more than half of Russia's campaigns and all manned missions to the International Space Station (ISS) are launched.
Since 2005, when Moscow ratified a long-term extension of its rental agreement with Kazakhstan, it has disputed the amount Russia pays for launches from the spaceport and has sought to limit such missions. Last year, the two governments tangled over safety concerns with Soyuz rockets, which dump spent stages on Kazakh territory during missions that take a northerly trajectory.
In July, tensions increased following the spectacular failure of a Russian Proton M/Block DM3 that crashed seconds after liftoff from its Baikonur launch pad, releasing tons of highly toxic fuel into the air. The Proton's return to flight, carrying the Astra 2E satellite for Luxembourg fleet operator SES, was slated for Sept. 17. But Kazakhstan's environmental worries contributed to a half-month delay to the commercial mission, which at press time was scheduled for Sept. 30.
To reduce its reliance on Baikonur, Moscow is investing in a new launch site in Russia's far-eastern Amur region. Under construction since 2011, the new Vostochny Cosmodrome is running a few months behind schedule, Russian government officials say, but initial missions are still scheduled to begin in 2015 with the launch of Soyuz-2, the newest iteration of Russia's venerable three-stage rocket.
By 2020, Vostochny is planned to loft nearly half of all Russian missions, including the new Angara family of rockets that will replace most Soviet-era launchers, such as Proton, and all manned space flights. The goal, according to Russian officials, is to reduce launches at Baikonur to 11% by the end of the decade, from 65% today.
“By 2020, the new heavy-launcher Angara is planned for launch at Vostochny, and after that, 2030, we plan to finalize and put into operation a reusable rocket and space system,” said Sergey Saveliev, deputy head of Russian space agency Roscosmos, during the 64th annual International Astronautical Congress here last week.
Russia's new Angara rocket family, in development at the Khrunichev State Research and Production Space Center since the mid-1990s, is based on the liquid oxygen/kerosene-powered URM-1 Common Core Booster (CCB). More environmentally friendly than Soviet-era launchers, the Angara line will rely on a single CCB to power the light-weight Angara 1.2; the heavy-lift Angara A7, designed to launch manned missions to the Moon and beyond, will require up to seven boosters.
In addition to launch facilities and an automated ground control and instrumentation complex at Vostochny, Moscow is developing a tourism center, scientific research and education facilities and a test and integration site in a nearby town. Some hardware production facilities may also be moved to the Amur region to reduce transit costs and create jobs.
By 2030, the cosmodrome is expected to support advanced space missions, including manned exploration, using electric and nuclear-powered interplanetary tugs for lunar and deep-space campaigns.
“The plan is to use the Vostochny space port primarily for our human spaceflight program,” says Alexey Krasnov, Roscosmos director of human spaceflight, notably in support of a new transportation system that he says will be capable of carrying four crew. “However, initially we will use it for launching conventional vehicles that we are using today. We'll start with cargo vehicles, like Progress, then transfer to the Soyuz vehicles, which are being modified.”
The new cosmodrome will also support Russia's communications, relay, navigation, remote-sensing and disaster-monitoring satellite programs, as well as “initial use of manned and unmanned spacecraft for in-orbit servicing, including their refueling,” says Aleksey Romashkin of Russia's Central Research Institute for Machine Building.
Over the next two decades, Vostochny will enable an ambitious slate of space endeavors, including plans to deploy new modules to Russia's ISS segment that could serve as the basis for a national space station program after the ISS is decommissioned, or function as free-flying assets for missions in high Earth orbit. A lunar surface descent/ascent complex for operating in a low-gravity environment is also in the works, as are robotic spacecraft for Moon exploration and, ultimately, a permanent lunar base.
“We wish to combine our resources in low Earth orbit and exploration,” Krasnov says. “That's how we structure it, with robotics and human spaceflight programs, which could be a very good combination.” More.

NASA Plans Electric-Propulsion Test Stands

NASA Dryden is building testbeds to advance understanding of electric propulsion for aircraft

Electric propulsion is already here, albeit on a small scale, and now NASA is looking ahead to the technology that would be required to power a regional aircraft in 10-20 years or a narrowbody airliner in 30-40 years.
But the agency intends to start small, with tests to first understand, then model the behavior and efficiency of electric propulsion system components. These will feed into ground, and potentially flight, tests of a distributed propulsion system that would be closely integrated with the airframe.
NASA has laid out a technology road map that would enable 1-2-megawatt electric propulsion for a 50-seat regional in 10 years, 2-5 megawatts for a 100-seat aircraft in 20 years, and 5-10 megawatts for Boeing 737-class airliners in 30 years. Funding is scarce, however, so development is starting at the kilowatt level, but this could spin off to the general-aviation industry, enabling new concepts in light aircraft.
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NASA's AirVolt test stand will measure the efficiency of individual electric propulsion system components. 
The critical design review has just been completed for an electric propulsion test stand, says Starr Ginn, Aeronautics Mission Research Directorate chief engineer at NASA Dryden Flight Research Center. The stand, dubbed AirVolt, is set to be completed by March 2014, and will be used to measure accurately the efficiency of individual system components, from batteries and motors to speed controllers and propellers.
Dryden's AirVolt is a first step toward NASA's long-term goal of turbo-electric distributed propulsion, where a turbine-driven alternator or generator powers multiple propulsors integrated with the airframe. This has the effect of increasing the effective bypass ratio, and propulsive efficiency, while enabling configurations that use the propulsion system to improve aerodynamics or provide flight control.
Testing is planned to begin by the end of next summer, says Sean Clarke, NASA flight systems engineer. The single-string stand will be capable of producing up to 500 lb. of thrust from a 6-ft.-dia. propeller. Initial tests will involve a 40-kw power train. “We will be able to isolate a given component and to validate its efficiency before we put it into a stack of propulsors,” he says.
As a next step, NASA Dryden has awarded a contract to Empirical Systems Aerospace to build the Hybrid Electric Integrated System Testbed (Heist). This will be an 80-kw ground test bench for turbo-electric distributed propulsion, with a flight-like architecture sized for eventual flight testing—by modifying Dryden's TG-14 motor glider or designing and building a dedicated testbed aircraft. “The nice thing about electric propulsion is you are not stuck with traditional aircraft designs,” notes Ginn.
Heist, which recently began, is an 18-month program and hardware should be entering test in a year, says Clarke. The test bench is planned to have a turbo-generator, AC/DC converter, battery system, electronic controller and a DC bus distributing power to 8 or 12 4-6-in. ducted fans, each with its own electric motor and speed controller. “Whether it is just a stand to test power management and distribution or is integrated into an airframe-like structure” is under discussion, says Ginn.
In addition to the real-time management of generator loading, battery capacity and power demand, Heist will allow study of distributed-propulsion algorithms that synthesize individual propulsor commands based on total system thrust targets set by the pilot. “We will study how to schedule loads on the generator, and charging and discharging of the batteries in different flight modes,” says Clarke.
DC bus stability is an issue as power levels are scaled up, because the magnetic inertia of large motors induces electromotive force (called back-EMF) on the bus. This can lead to motor runaways. Heist will allow the issue to be assessed on a power scale compatible with a flight vehicle, he says.
NASA plans to increase its research into distributed electric propulsion over the next couple of years, demonstrating a kilowatt-class architecture as a step toward the megawatt power levels needed for commercial aircraft. So far, for Dryden, “it's not an increase in resources, but a shift, because it's strategic for us to get into hybrid electric,” says Ginn.
The ultimate goal on NASA's road map is 10-megawatt-plus hybrid-electric propulsion for a 300-seat airliner, which could be 40 or more years away. “We recognize a great deal of technology development is needed [to get there]. But there is an opportunity to begin gathering data today,” she adds. “What we are starting to work on can be scaled up to larger aircraft. A low-cost kilowatt-class prototype can exercise in a flight environment technology that is scalable to 2-5 megawatts.” More  Source:Aviation Week & Space Technology   Sep 30, 2013 , p. 50

NASA comes to a halt after U.S. government shutdown
U.S. Congress has failed to agree on a federal budget for 2014, setting off a government shutdown that also affects NASA.
"Around 97% of NASA's 18,000 employees are off the job. Twitter, Facebook, Google Plus and other social media accounts are going dark. NASA's website is being pulled offline. NASA Television has also ceased broadcasting," Universe Today reported.
Non-government facilities, which still have some funding left, continue to work for NASA at least for a brief period of time. According to the Planetary Society blog, "All of NASA's missions that are operated out of JPL and APL are continuing to operate normally today and for at least a week. At JPL, that includes: Curiosity; Opportunity; Odyssey; Mars Reconnaissance Orbiter; Cassini; Dawn; Juno; Spitzer; the Voyagers; and WISE, among many others. At APL, that includes MESSENGER and New Horizons. It also includes the Deep Space Network, which JPL manages but which is subcontracted out to other entities for actual operation."
Spaceflight Now wrote that "NASA is planning to launch the Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft to Mars in November to examine the Red Planet's atmosphere. ... Media reports indicate that if the shutdown is lengthy, MAVEN could miss the launch window and have to try again in 2016."
Source: Universe Today, Planetary Society, Spaceflight Now

Artist's concept of the Mars Orbiter Mission
Hectic activity at Sriharikota on Mars-bound spacecraft

October 7, 2013 - India's first Mars probe is preparing for launch in late October on a trial run to the red planet to lay the technological foundation for future Indian deep space missions. 
Set for liftoff as soon as Oct. 28, the Mars Orbiter Mission will demonstrate deep space navigation and communications, interplanetary travel, spacecraft autonomy, and the complex make-or-break rocket burn to place the spacecraft in orbit around Mars. 
Only the United States, Russia and the European Space Agency have successfully dispatched robots to Mars before. The Indian Space Research Organization hopes to be the fourth space agency to accomplish the feat. 
The Indian orbiter also carries a small camera to return medium-resolution color imagery of the Martian terrain, a thermal infrared spectrometer to measure the chemical composition of the surface, and instruments to assess the Mars atmosphere, including a methane detector. 
But Indian officials rank the orbiter's technological objectives higher than its science goals, according to J.N. Goswami, director of ISRO's Physical Research Laboratory and a top scientist on the Mars Orbiter Mission. 
Goswami gave a briefing on the mission in March at the Lunar and Planetary Science Conference in Houston. 
Engineers put together the Mars Orbiter Mission in quick time. Goswami said ISRO approved the mission in August 2011, with all the hardware assembled on the orbiter in less than two years. 
Designers based the spacecraft on the Chandrayaan 1 lunar orbiter, which India successfully placed in orbit around the moon in November 2008 and successfully operated until August 2009. 
India's Mars-bound spacecraft undergoes electromagnetic interference testing. Credit: ISRO
The $73 million Mars Orbiter Mission has a launch window opening Oct. 28 and extending through Nov. 19. 
The Jet Propulsion Laboratory is providing communications and navigation support for the mission, which requires the use of NASA's Deep Space Network, a set of three tracking stations in California, Spain and Australia. 
Indian scientists last week feared the partial shutdown of the U.S. government - caused by political wrangling in Washington - could threaten India's access to NASA's tracking and navigation expertise. 
"NASA/JPL authorities have reaffirmed support for the Mars Orbiter Mission as planned and stated that the current U.S. government partial shutdown will not affect the schedule of Mars Orbiter Mission," ISRO said in a statement released Saturday. 
The spacecraft arrived at the Satish Dhawan Space Center on India's east coast Thursday after an overland trip from its factory and test facility in Bangalore. 
Over the next three weeks, technicians will add rocket fuel to the spacecraft, which is about the size of a compact car. Then engineers will hoist the 2,976-pound probe atop an amped-up version of India's Polar Satellite Launch Vehicle called the PSLV XL. 
Boosted by enlarged strap-on rocket motors, the PSLV will hurl the Mars-bound spacecraft into an elliptical loop with a peak altitude about 14,300 miles above Earth. 
The Mars Orbiter Mission will propel itself out of the grasp of Earth's gravity with six engine burns, concluding the escape maneuvers around Nov. 30 and embarking on a 10-month interplanetary cruise to the red planet. 
Arrival at Mars is scheduled for Sept. 21, 2014, one day before the arrival NASA's MAVEN Mars orbiter, which is on track for launch directly to Mars from Florida on Nov. 18. 
The Indian spacecraft will enter an orbit ranging in altitude from 234 miles to nearly 50,000 miles above Mars, completing a lap around the planet every 3.2 days. Source: SPACEFLIGHT NOW  Payloads of Mars Orbiter     Mission Profile