Hypersonic plane to fly at 20 times the speed of sound 17th July 2012 Research into stealth technology by the Defense Advanced Research Projects Agency (DARPA) in the 1970s and 1980s led to the world's most advanced radar-evading aircraft. This provided a major national security advantage to the United States. Today, that strategic advantage is being threatened as China and other nations' abilities in stealth and counter-stealth improve. Restoring that battle space advantage requires advanced speed, reach and range. Hypersonic technologies have the potential to provide the dominance once offered by stealth to support a variety of national security missions. Extreme hypersonic flight at Mach 20 (i.e. 20 times the speed of sound) is an area of research where major advances have eluded researchers for decades. Thanks to programs by DARPA, the Army and Air Force in recent years, however, new information has been obtained about this challenging subject. Integrated Hypersonics (IH) is a project currently underway at DARPA. This aims to test a full-scale, hypersonic "X-plane" by 2016. Travelling at Mach 20 (20,900 km/h), it could fly to anywhere in the world in under an hour. DARPA has already tested an early prototype hypersonic aircraft - the Falcon Hypersonic Technology Vehicle 2 (HTV-2) - which achieved Mach 20 in August 2011. However, this only remained airborne for nine minutes.
The IH program expands on previous research to include five primary technical areas: thermal protection system and hot structures; aerodynamics; guidance, navigation, and control (GNC); range/instrumentation; and propulsion. At Mach 20, vehicles flying inside the atmosphere will experience intense heat, exceeding 3,500 degrees Fahrenheit, which is hotter than a blast furnace capable of melting steel, as well as extreme pressure on the aeroshell. The thermal protection materials and hot structures technology area aims to advance understanding of high-temperature material characteristics to withstand both high thermal and structural loads. A new launch vehicle will be designed for the aircraft. Rocket propulsion will also be integrated into the vehicles, offering a mid-flight boost to extend their range. DARPA will host a Proposers' Day on 14th August 2012, to detail the technical areas for which proposals are sought. "By broadening the scope of research and engaging a larger community in our efforts, we have the opportunity to usher in a new area of flight more rapidly and, in doing so, develop a new national security capability far beyond previous initiatives," said Air Force Maj. Christopher Schulz, DARPA program manager.
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Late in the night Gholson came to the union captain's bedside for Miss Harper. Charlotte had sent him; the doctor had left word what to do if a certain patient's wound should re-open, and this had happened. The three had succeeded in stanching it, but Charlotte had prevailed upon Miss Harper to lie down, and the weary lady had, against all her intentions, fallen asleep. I was alone with the wounded captain. He did not really sleep, but under the weight of his narcotics drowsed, muttered, stirred, moaned, and now and then spoke out. "You're right, Sam," said George Bynes, who had hit up many a century for his town in bygone days, "tain't cricket. Else it's a[Pg 28] fluke; the man didn't ought to be allowed to hold bat in his hand. It's spoiling other folks' sport." But the Clockwork man made no reply. He stood in the middle of the stage and slowly[Pg 96] lifted a finger to his nose. The Curate's doubts returned. Something seemed to occur to him as he examined his companion more closely. "You haven't been taking anything, my good man, have you? Anything of an alcholic nature?" Walk equal courses in their yearly round, I. ¡°There was no need. She had taken only the imitations¡ªthe ones you found.¡± ¡°It¡¯s funny,¡± Jeff remarked. ¡°This-here psychology I¡¯ve read about ain¡¯t so far wrong when it says that folks who gets the wrong slant on a thing comes to believe it so strong that even the truth looks like a fib to them.¡± Then he began to come to himself and to listen to all that Felipa had to tell him of the many things she had not put in her short and labored letters. He saw[Pg 140] that she looked more beautiful and less well than when he had left her. There was a shadow of weariness on her face that gave it a soft wistfulness which was altogether becoming. 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She wondered if Cairness had been able to get the cut alfalfa covered. Then she took the kittens with her to the house and went into the kitchen, where the Chinese cook already had a fire in the stove. She ordered coffee and toast to be made at once, and leaving the kittens in the woodbox near the fire, went back to the sitting room. She gave a dry little sob of unutterable glad relief and tried to raise her voice and call to him, the call they used for one another when they rode about the ranch. But the sound was only a weak, low wail. "Yes; you're in nice shape to send to the guardhouse. I'd sent you there quick enough if you were well, for telling me such a preposterous lie. You've usually paid more respect to my intelligence by telling me stories that I could believe if I wanted to, as I usually wanted do; but this is too much." "And then something happened," Dr. Haenlingen said tightly. "I know." It was quite dark when they reached Eggs Hole, and parted after kisses no longer as shy as they used to be. The year wore on. Kimberley and Ladysmith were relieved. Rye hung out its flags, and sang "Dolly Grey" louder than ever. Then Mafeking was saved, and a bonfire was lit up at Leasan House, in which a couple of barns and some stables were accidentally involved. Everyone wore penny medallion portraits of officers¡ªRoberts and Baden-Powell were the favourites at Odiam, which nearly came to blows with Burntbarns over the rival merits of French. While Reuben himself bought a photograph of Kitchener in a red, white, and blue frame. "The wife of a vassal would not have taste enough to buy such as these; and there is but one about Winchcombe who could work so well. And, by my faith, I now remember that it was part of the tenure by which I some time since granted land, to present a pair of gloves.¡ªWas it not a fair-looking damsel, one Stephen Holgrave's wife, that brought them?" John Ball pressed on with the multitude; but the immediate proximity of the palace, where all was splendour and motion, was not to the liking of one who till that day had never even dreamed of such things as had now met his sight. His nerves were weak, and he felt irritated at the insolence with which the royal guards, and the pages of the nobles, drove back the populace. His body, too, was weak, and he felt exhausted with his long and fatiguing walk: slowly and sadly he at length retraced his steps to his humble dwelling in the Minories. HoMEÐÂÏÊÏã·¹µê¾©´ó·µêµç»° ENTER NUMBET 0016hzdklc.com.cn