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Chinese PLANAF J-11BH conducted dangerous intercept on U.S. Navy P-8A Poseidon MPA

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The world is starting to get a better idea of what the U.S. military's proposed new space plane might look like.

Last week, aerospace firm Northrop Grumman released artwork depicting its conception of the XS-1 space plane, which it's designing under a $3.9 million contract from the U.S. Defense Advanced Research Projects Agency (DARPA).

Northrop Grumman is one of three companies competing for the right to build the unmanned XS-1, which is short for "Experimental Spaceplane." The other two are Boeing and Masten Space Systems, both of which also won yearlong "Phase 1" initial design contracts in July.

DARPA wants the XS-1 to make spaceflight much more routine and affordable. The reusable vehicle should be able to fly 10 times in a 10-day span and launch 3,000- to 5,000-lb. payloads to orbit for less than $5 million per flight, officials have said.

XS-1 will probably feature a reusable first stage and one or more expendable upper stages. The first stage will fly to suborbital space at hypersonic speeds, then return to Earth to be used again; the upper stages will deploy payloads to orbit.

Northrop Grumman is teaming with other aerospace companies on its design, tapping Scaled Composites to head manufacture-and-assembly work and Virgin Galactic to lead XS-1 operation.

"Our team is uniquely qualified to meet DARPA's XS-1 operational system goals, having built and transitioned many developmental systems to operational use, including our current work on the world's only commercial spaceline, Virgin Galactic's SpaceShipTwo," Doug Young, vice president for missile defense and advanced missions at Northrop Grumman Aerospace Systems, said in a statement.

"We plan to bundle proven technologies into our concept that we developed during related projects for DARPA, NASA and the U.S. Air Force Research Laboratory, giving the government maximum return on those investments," he added.

Northrop Grumman is not alone in reaching out to other firms for assistance in developing an XS-1 design. Masten is working with XCOR Aerospace, and Boeing is teaming with Jeff Bezos' secretive firm Blue Origin.

DARPA expects to hold a Phase 2 competition next year to see which company makes it to the flight-test stage of XS-1 development. (The agency only has enough money for one XS-1 contractor in the end.) Officials currently envision that the first orbital mission of XS-1 will take place in 2018.

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Military aircrews may no longer have to choose between staying safe and staying cool. The U.S. Army's new personal cooling systems, worn underneath body armor, can help troops beat the heat, without removing their protective gear.

Soldiers can wear the Light-Weight Environmental Control System, or LWECS, directly against their bodies. A small battery that fits inside body armor powers the system, according to the U.S. Defense Department (DoD).










"It's the same technology that's in your air conditioner or in your refrigerator, except instead of conditioning air, it chills a fluid. And then it pumps that fluid through a tube-lined cooling vest," Brad Laprise, a mechanical engineer at the Natick Soldier Research, Development and Engineering Center (NSRDEC) in Natick, Massachusetts, told Armed with Science, the DoD's science blog. [7 Technologies That Transformed Warfare]

The cooled fluid travels through approximately 110 feet of tubing coiled inside the vest, which is worn against the skin. Though the unit that cools the fluid is small, measuring only 3.5 inches across, it provides 120 watts of cooling power, about the same as a small refrigerator, according to Laprise.

Helicopter pilots and their crews already use aircraft-mounted cooling systems to beat the heat. But while these systems have been shown to improve endurance and performance levels in hot climates, many crewmembers avoid using them because they tend to be inconvenient.

Such onboard cooling devices are equipped with tethers that soldiers need to attach themselves to in order to cool down. But moving around the back of a cramped helicopter on a tether is no easy feat, the researchers said. The new, tether-free system is expected to resolve this and other issues associated with staying cool mid-flight.

To gauge the effectiveness of the new system, researchers from the NSRDEC and the U.S. Army Research Institute of Environmental Medicine recruited five volunteers to try out the cooling devices at NSDREC's climate chambers.

The volunteers were outfitted in full protective gear, including an over-garment, a mask, a hood, footwear covers and gloves, in addition to the soldiers' standard field gear, or uniform.

Inside the climate chamber, the five participants paired up to simulate air missions in desert and jungle conditions. One soldier in each pair wore the LWECS system during the trials.

To simulate typical air missions, in which crew members repeatedly exit and board the aircraft, the participants sat for 50 minutes and walked for 10 minutes each hour. Each session lasted 11 hours.

During this time, researchers monitored the participants' core and skin temperatures and heart rate, as well as fluid intake and bodily excretions. While researchers are still shifting through the data from the tests, early results indicate that the cooling system works well.

"Physiologically, we're seeing that their body core temperatures are lower, their heart rates are lower," said Bruce Cadarette, a research psychologist at the U.S. Army Research Institute of Environmental Medicine. The results suggest that the cooling system does what it was designed to do, he said.

The researchers created the new system with specific military personnel in mind, particularly aircrew chiefs, who are responsible for loading and unloading cargo, Cadarette said. These men and women need a cooling system that lets them do their job without being hampered by tethers.

"The other people that we're concentrating on are the medics, who have to fly out in the back of helicopters, and who have to go out and treat wounded in the field, load them onto stretchers [and] get them onto the back of the helicopter," Cadarette said. He said he expects U.S. air troops in both desert environments and tropical climates will eventually use the lightweight system.

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Research raises concerns for new Army helmet design
Tests show added components may produce unexpected pressure
Aug. 24, 2014 - 06:00AM |

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By Kevin Lilley
Staff report
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Military Technology
Tests by Navy researchers on a new Army and Marine helmet design, complete with a visor and a jaw protector, showed blast waves could bounce off the added components and produce unexpected pressure, according to a recent research paper.

The Conformal Integrated Protective Headgear System, or CIPHER, prototype came under attack from all sides during the test, conducted by the Naval Research Laboratory, and in all configurations: Helmet only, helmet and visor, helmet and jaw protection, and the full-face coverage of visor and jaw protector.

The findings showed that adding face protection didn’t necessarily mean lessening blast-wave impact. For example, according to the report:

■ In a front-facing blast, pressures on the forehead were higher with the jaw protector, or mandible, in place and with the mandible-visor combination than they were with the helmet alone.

■ Wearing just the jaw protection for a front-facing blast doubled the strength of the secondary shockwave pressure on the forehead from 2 atmospheres (one atmosphere is a little less than 15 pounds per square inch) to 4 atmospheres.

■ In a rear-facing blast, pressures on the forehead were more than twice as high for the mandible-visor combination than for the helmet alone.

The tests could help designers mitigate the pressure increases with slight structural changes to the helmet, according to the study’s lead researcher. But there is no clear target.

“The military actually has specific criteria that helmets have to meet to be certified for use in ballistic and blunt force,” said David Mott, an NRL aerospace engineer. “No such criteria exists for pressure because the medical community is still working on what the injury mechanisms are, and we don’t know where to set those desirable levels anyway, at this point.”

Follow the bouncing wave
The tests centered on the helmet’s “suspension geometry,” the scientific term for what’s between the wearer’s head and the outer shell.

“You need that standoff for that blunt-impact and ballistic-impact protection ... that’s the way the helmets work,” Mott said. “We had seen that blast waves can infiltrate that gap.”

The visor and the mandible may blunt the initial blast, but they can also channel ricocheting blast waves into unexpected spaces around the wearer’s head. For example, according to the report, the mandible may “trap” a blast wave ricocheting from the wearer’s chest, which could then combine with the initial “incident wave” and lead to a “delayed, stronger forehead peak.”

The study recorded a forehead pressure of just over 9 atmospheres in a front-facing blast with the visor and mandible in place; the top pressure was just above 8 atmospheres in the helmet-only test.

The paper points out that increased pressures in one area generally come with decreased pressures in others. In the front-blast test, the visor-mandible combo dropped the peak of the highest-pressure wave on the back of the head by half when compared with the helmet-only setup, for instance.

It’s one of a series of tradeoffs designers must make, Mott said — determining which areas to channel blasts away from, and balancing the need for blast-wave protection against other concerns: A soldier may want to wear the mandible or visor, even with elevated blast-wave pressures in some areas, to keep a bomb fragment from bouncing off his face.

Future tests
The prototype, which was designed under the Helmet Electronics and Display System-Upgradable Protection, or HEaDS-UP, program by Army researchers in Natick, Massachusetts, is far from finished with testing. Mott offered a series of steps that could improve future findings:

■ Blast reaction. “We’re moving toward including the material response of the head and the helmet” to the explosion, he said. The latest tests were conducted using “stationary, stiff bodies.”

■ Torso tracker. “Although we had a very detailed model for the head and helmet for these calculations, we had a pretty simple torso and shoulders,” he said. A more realistic mannequin would yield better data, especially when measuring ricochets off the body.

■ More gear. That torso will need a tactical vest, at least — Mott said knowing what soldiers likely will wear in theater will help fully track the blast waves. “We don’t have all the relevant geometry in the calculations yet,” he said.

Mott and colleagues Ted Young and Doug Schwer published their findings with the American Institute of Aeronautics and Astronautics. While they don’t address suggested improvements to the gear, the research “makes us optimistic that we can find combinations of geometry, either for the accessories themselves or for the suspension, that may reduce that threat, reduce those pressure loads that we’re seeing,” he said.

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US hypersonic missile test failed shortly after takeoff
By: DAN PARSONSWASHINGTON DC Source: Flightglobal.com 3 hours ago
Story updated to include comments from US Defense Department in paragraph 6.

A test of the Army’s advanced hypersonic weapon (AHW) was aborted shortly after an early morning takeoff on 25 August.

Around 04:00 Eastern Time, the US Army Space and Missile Defense Command launched the weapon but were forced to terminate the test “due to an anomaly”, according to a statement from the Office of the Secretary of Defense (OSD). It was the second test of the Army's hypersonic glide vehicle.

The weapon is the most promising of several technologies aimed at delivering a conventional warhead from US soil anywhere in the world within an hour of strike authorisation. The advanced hypersonic weapon is being tested by the army and Sandia National Laboratories, which is owned by Lockheed Martin Corp. The venture is a part of an umbrella defence department programme called Conventional Prompt Global Strike technology development (CPGS).

“Due to an anomaly, the test was terminated near the launch pad shortly after lift-off to ensure public safety,” the statement reads. “There were no injuries to any personnel.”

The failed US test comes on the heels of a successful Chinese hypersonic vehicle test in January that news reports say resembles CPGS.

OSD spokeswoman Maureen Schumann could not shed light on what went wrong with the test. The intended objective was to collect data on the glide vehicle during long-range atmospheric flight and to test and develop hypersonic glide capability, she said. The CPGS program is event driven, with the results of each test informing future experimental flights. Schumann said the results of the investigation would inform the programme's schedule moving forward.

“Program officials are conducting an extensive investigation to determine the cause of the flight anomaly,” the statement said.

AHW is a cone-shaped vehicle with winglets designed to fly within earth’s atmosphere faster than the speed of sound. The vehicle was successfully tested in 2011, when it was launched from the Pacific Missile Range Facility in Hawaii. It flew 3,700km in about half an hour to the intended target in at the Reagan Test Site on the Marshall islands.

The US Air Force also is developing a global strike capability called the conventional strike missile. The service also has launched a joint effort with the Defense Advanced Research Projects Agency (DARPA) called the hypersonic technology vehicle 2.

A 2011 test of that vehicle, which is capable of flying at 11,339.1kt (2,100 km/h), ended when an a flight anomaly caused it to splash into the Pacific Ocean. A subsequent investigation showed that material sheared from the machine’s fuselage, causing it roll and triggering its onboard computer to crash land.

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Affordability Challenge In Pursuit Of Army JMR/FVL
Higher speed will not be enough to persuade the U.S. Army to pursue an advanced rotorcraft
Aug 25, 2014 Graham Warwick | Aviation Week & Space Technology
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Speed Vs. Cost
A version of this article appears in the August 25 issue of Aviation Week & Space Technology.


Bell must prove that the cost and complexity of a tiltrotor can be reduced significantly. Credit: Bell Helicopter Concept

Proving affordability is the biggest challenge facing Bell Helicopter as well as the Sikorsky/Boeing team as they build and fly advanced rotorcraft demonstrators aimed at the U.S. Army’s requirement to replace its Sikorsky UH-60 Black Hawk helicopters from the mid-2030s.

The two teams have been chosen to fly high-speed rotorcraft in 2017 under the Joint Multi-Role (JMR) technology demonstration, a precursor to the planned Future Vertical Lift Medium (FVL-M) program to replace first the utility UH-60s and later the Army’s Boeing AH-64 Apache attack helicopters. FVL-M could also replace the Navy’s Sikorsky MH-60 Seahawks and the Air Force’s Black Hawk variants.

Between them, the three companies supply most of the Pentagon’s rotorcraft. For Boeing and Sikorsky, winning one of the two JMR “X-plane” contracts and an FLV-M “Y-plane” fly-off planned for the mid-2020s is crucial to protecting their incumbency with the Army. For Bell, FVL-M would keep the company in the Army business after the OH-58D Kiowa Warrior is phased out.

They faced competition for the demonstrator contracts from two companies offering a “small prime, big team” approach to JMR/FVL—AVX Aircraft and Karem Aircraft. But ensuring the teams had the capability to accomplish the demonstration was a key part of the Army’s evaluation, and the “Big Three” and their suppliers brought significant engineering resources and cost-sharing to the table. Both AVX and Karem are waiting to hear if the Army will fund them to continue some technology development work on their designs.

Agreements in place with all four bidders called for 50:50 cost sharing, but both Bell and Sikorsky/Boeing say industry is investing much more than the government. The reason is the program’s importance to the rotorcraft manufacturers. JMR/FVL will “reinvigorate industry with an opportunity to design an aircraft from the ground up,” says Pat Donnelly, director of the Sikorsky/Boeing JMR team, noting that winning FVL-M would be “a significant continuation of the industrial base built up for Black Hawk and Apache.”

But FVL-M is not a done deal for the JMR winners. The technology demonstration is intended to ensure that advanced rotorcraft capable of at least 230 kt.—50% faster than the Black Hawk—are viable candidates for procurement. However, the Army has yet to decide whether and when to launch a program, or if it will be an advanced rotorcraft, a new conventional helicopter or another upgrade to the UH-60.

“The timeline is a government decision. The best we can do is execute the [demonstration] program well, show the Army the realm of the possible by 2017 and make it more likely they will want to commit,” says Chris Gehler, director of military program operations for Bell. “Affordability is critical.” Cost-prohibitive leap-ahead performance is not a solution, he says. “Everything we are doing is focused on bringing an affordable vehicle to the game. We have to give them a reason to continue.”


Sikorsky/Boeing must prove the benefit of coaxial rotors and propulsor to the utility mission. Credit: Sikorsky-Boeing Concept

For Bell, proving its 280-kt.-cruise V-280 Valor tiltrotor is affordable is crucial because the Bell Boeing V-22 Osprey has established the tiltrotor’s reputation as capable, but costly to produce and maintain. “With tiltrotor you get inherent performance, but the question is affordability,” says Gehler. “The V-280 is a clean-sheet third-generation tiltrotor. Our focus is on reducing cost and weight, increasing reliability and performance, and making the aircraft come together in the most affordable way.”

The main driver of cost is weight, Gehler says, so the V-280 makes extensive use of composites in the wing, fuselage and V tail. Wing skins and ribs are of honeycomb-stiffened sandwich construction with large-cell carbon cores for fewer, larger and lighter parts. Skins and ribs are paste-bonded together, eliminating fasteners. Costs are reduced more than 30% compared with a scaled V-22 wing, Bell says.

For Sikorsky/Boeing, the 230-kt.-plus SB-1 Defiant is a scale-up of the rigid coaxial-rotor compound helicopter configuration already flown at smaller size with Sikorsky’s X2 Technology demonstrator and being built at a larger size with two industry-funded S-97 Raider light tactical helicopter prototypes, the first of which is to fly by year-end. In addition to affordability, the team will have to demonstrate the utility of the SB-1’s rigid rotors and tail-mounted propeller in the Black Hawk’s transport missions.

“Our hingeless coaxial rotors provide better maneuverability and handling, and allow us to reduce the height between the rotors for lower drag,” says Donnelly. “The goal is long range and high speed without compromising low-speed maneuverability. The Defiant will operate like a helicopter in the landing zone, but have the speed and range of a tiltrotor.” The variable-pitch propulsion will provide acceleration and deceleration, nose-up/-down pitch pointing and can be declutched for safety and quietness in the landing zone, he says.

In the phase just ended, each contender produced two rotorcraft designs, for the air vehicle concept demonstrator (AVCD) and for an objective aircraft meeting the model performance specification (MPS)—the Army science and technology community’s best guess at the FVL-M operational requirements, which will not be set for several more years. “The AVCD is a fully representative, full-scale flight demo of the MPS design to provide the Army with an accurate reflection of what to expect in a future medium-class aircraft,” says Gehler.

The AVCD designs used available technology, including legacy engines: General Electric T64s for Bell’s V-280 and Honeywell T55s for Sikorsky/Boeing’s Defiant. The MPS designs were not limited to what is available now, and could be designed around the Army’s planned fuel-efficient Future Affordable Turbine Engine, for which GE is building a demonstrator. “Composites use in the AVCD fuselage is similar to the V-22, with carbon skins and aluminum stringers. MPS has a completely composite fuselage,” says Gehler.

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