Tuesday, 19 August 2014

The Rise of Radical New Rotorcraft

At a secret facility, aerospace engineers are plotting to end the helicopter as we know it, and devising new rotorcraft to replace it.

By Jeff Wise
Sikorsky technicians at a hangar in Florida work on the S-97 Raider, the first production-ready prototype of a compound-coaxial helicopter.
Nathaniel Welch
June 3, 2014 6:30 AM Text Size: A . A . A
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The building doesn't look like much—one of several nondescript hangars alongside an airstrip on the edge of the Everglades, baking in the eternal monotony of the central Florida sun.

This is the home of Sikorsky Aircraft's Area 31, where the company works on its most advanced rotorcraft projects. Like Area 51, the famously clandestine Air Force base in the Nevada desert, this airfield is home to experimental aircraft being built and tested. The mystery projects here need to be kept not only from other nations but from other aviation companies too. Millions, possibly billions, of dollars are at stake. For that reason, Sikorsky is hesitant to let journalists onto the grounds and does so only if the tour is restricted and the photography limited.

Inside the hangar, bathed in fluorescent light from banks of industrial lamps, is a molasses-dark fuselage with unusual twin fins jutting vertically from its tail. The fin structures are vertical stabilizers with rudders built in. Even at a glimpse, the half-finished airframe is something new.

This is the S-97 Raider. When it takes to the air in 2015, it will be the first production-ready prototype for a new kind of rotorcraft, the compound-coaxial helicopter. The Raider has two rotors that turn in opposite directions on a central mast, enabling it to fly up to 275 mph. That's more than 100 mph faster than a conventional helicopter, giving it twice the range.

The S-97 is among an emerging generation of advanced craft that could redefine the meaning of vertical-lift aviation. In 2011 the Army funded the Joint MultiRole Rotorcraft Technology Demonstrator (JMR-TD) program. This is the first step in an effort to replace the military's entire inventory of helicopters. Retired first will be the UH-60 Black Hawk, to be replaced with the Future Vertical Lift Medium, at the earliest in 2030.

The FVL Medium will have big shoes to fill. The Black Hawk provides the bulk of vertical-lift capability for the U.S. Army, Navy, Marines, Special Operations Command, and Coast Guard. It first entered service with the Army in 1979; over the next 30 years, more than 2300 aircraft saw service at home and abroad. The Black Hawk and its variants have proven track records but are limited by a maximum speed of 183 mph.

Aside from the FVL Medium, the Pentagon envisages three other classes of future flying machines that will have roots in this program: the FVL Light, to replace the Kiowa scout helicopter; the FVL Heavy, to replace the brawny twin-rotor Chinook; and the FVL Ultra, a brand-new class of aircraft that would combine the hauling capacity of a C-130 cargo plane with the ability to take off vertically. If the Pentagon plan comes together, these machines will replace every U.S. military helicopter.

Changes on the battlefield are posing dangers for traditional helicopters. Longer range missiles can target bases and ships, putting helicopter staging areas at risk. Aircraft that can fly faster and travel farther can complete their missions with less risk. And, since more capable rotorcraft can cover more ground, the Pentagon can buy fewer of them.

Today's most advanced vertical-lift aircraft is the V-22 Osprey, used by the Marine Corps and U.S. Special Operations Command. The Osprey tilts its rotors 90 degrees to fly like an airplane and land like a helicopter. But the Army is looking for a smaller combat rotorcraft instead of an Osprey-size heavy lifter. The JMR Technology Demonstrator will be designed to carry 11 troops, compared with the Osprey's carry capacity of 24.

The other type of vertical aircraft is the jump jet, which can vector its engines toward the ground to hover. Examples include the AV-8B Harrier and F-35B Lightning II, both carrier-capable fighter airplanes. These are not well-suited as Army utility lifters and attack helos because they burn too much fuel and are not light or maneuverable enough to fly missions close to the ground.

The goal of the JMR-TD program is to create an aircraft that is as nimble as today's Black Hawk while hovering, but with a ferry range of 2100 miles and a cruise speed of more than 265 mph. Industry engineers declare that it's possible, but the Pentagon launched the JMR-TD program to be convinced. "It's an investment to inform ourselves about the technology that's available," Dan Bailey, the Army program's director, says. "What we are looking at is a leap ahead in capability."

Last year the Army narrowed the field to four JMR-TD competitors, including two giants—Sikorsky of Stratford, Conn., and Bell Helicopter of Hurst, Texas—and two tiny firms, AVX Aircraft Company of Benbrook, Texas, and Karem Aircraft of Lake Forest, Calif. Each was awarded $6 million to produce a design. This summer two of the four will be selected to turn that design into hardware, with flight tests from 2017 to 2019.

The Army has made it clear that whoever survives the downselect will not necessarily be the winner of a $100 billion production contract for building as many as 4000 aircraft. But even losing companies stand to gain by flying demonstration aircraft, since the JMR-TD designs will inspire versions suitable for civilian markets.

In a few decades these futuristic rotorcraft could be as common in the skies as conventional helicopters are today. "This is a step change," says Steve Weiner, Sikorsky's director of engineering sciences. "It's going to be similar to when fixed-wing airplanes went from piston to jet engines."

If next-generation rotorcraft will be more capable than today's fleet, they are also going to be considerably more expensive. It takes a lot of power to go fast, and bigger engines add both weight and cost. "If you want to go above 150 knots [173 mph], you're going to have to pay a premium of 50 to 100 percent," says Richard Aboulafia, an aviation analyst with the Teal Group. Pentagon-funded demonstrator programs allow manufacturers to work out the kinks of new designs and bring down prices.

"Looking downstream, it's obvious that there's certain commercial applications of this technology," Bell's Keith Flail says. Some niches will be easier to exploit than others. "Offshore oil rigs could be a market," Aboulafia says. With exploration moving into ever-deeper waters, a vehicle that can make twice as many trips ferrying rig workers in the same amount of time will be worth the steep price tag to the big energy companies.

Another potential market, Aboulafia says, is the VIP market. Corporate executives and other wealthy individuals already take helicopters on short-hop trips, but more advanced rotorcraft could ferry passengers as far as 500 miles, avoiding airport hassles.

In a more critical application, medevac, speed can mean the difference between life and death. "There's a thing called golden hour," AVX's Troy Gaffey says. "If you can get someone to a hospital within that time, they're a lot more likely to live."

If these early markets pan out for tilt-rotors or compound-coaxial helicopters, there's no telling how many other uses they'll have. Right now vertical lift means a conventional helicopter, with niches occupied by the jump jet and the tilt rotor. Some day that relationship could reverse, if this new generation of vertical-lift aircraft becomes the norm, relegating conventional helicopters to the fringe. "You'll see the ratio change in that direction," Flail predicts confidently. "The evolution is coming."

Those Aerial Photos Are Nice, But High-Tech Balloons Can Do So Much More

Remember the giant balloon that was floating around New York City last week? It turns out that it can do much more than capture cityscapes.

By Joshua A. Krisch
April 29, 2014 10:09 AM Text Size: A . A . A
Last week you might have seen the stunning overhead shots featured in the The New York Times and elsewhere, taken by a big white balloon that floated lazily above midtown Manhattan. Tethered to a trailer and hovering 800 feet above the city streets, the balloon—nicknamed "Lucy"—sported high-tech cameras as it bobbed about in urban airspace that is normally restricted for aircraft.

The balloon shot this skyscraper footage for architects and real-estate developers surveying the area, offering them a unique view of urban architecture. But Curt Westergard, president of the Digital Design and Imaging Service company that designed and launched Lucy, says tethered balloons are good for far more than shooting city vistas. They can also keep watch over borders, track natural disasters such as oil spills, and lots more.

"Balloons provide a simple, long-duration, quiet, aerial platform, which is accepted in cities that have very difficult flight restrictions," he says.

Building MRI


Gorgeous aerial photography is the attention-grabber, but Lucy doesn't always carry a camera in its payload. Sometimes, imaging in other parts of the spectrum is more helpful. For example, Westergard has strapped high-resolution infrared scanners to some of his balloons to gather complex data about the energy efficiency of older buildings.

"We'd like to find the most wasteful and the most efficient buildings on the planet, and give them a full-body MRI scan to find out how they are working," Westergard says.

During the winter, older, inefficient buildings often leak heat from specific locations along their facades or rooftops. Hoisted up to 1400 feet by Westergard's balloons, thermal infrared cameras can highlight problem spots and help companies save money and energy.

"We want to know what holes should be plugged," Westergard says. "How many gallons of oil does an inefficient building consume during a cold snap?"





All images via AirPhotosLIVE.com.

Westergard and his team did a lot of the early work without a contact—they just flew over other people's buildings to see how much they leaked. Now people hire him to do this.

Drone Driving School


As the Federal Aviation Administration starts to certify drones for commercial use, test centers will need reliable ways to prove that unmanned aircraft are safe and reliable. Westergard is now lobbying to bring his balloons to the FAA proving ground. Aerostatic balloons could function as tethered, moving obstacles, capable of changing altitude or position quickly.

"Our aerostat fleet could serve as traffic cones in the sky," he says, in tests to prove drone safety. "Drone test pilots could navigate around us and, even if they hit us, it's a lot cheaper than hitting a building or a Predator drone."

And well-chosen balloon payload could bring even more high-tech challenges to fledgling drones. Westergard has proposed that his balloons carry a radar reflector into the air in an attempt to deliberately sabotage a drone's signal to prove whether it's possible.

"The FAA is concerned that many of these drones are controlled at the same frequency as a garage-door opener," Westergard says. "We could provide not just a balloon, but a radar jammer." Once pilots prove that they can navigate through the static and maintain control of their aircraft, drones might be deemed safe enough to fly over residential areas.

Panoramic Search and Rescue


When famed aviator Steve Fossett went missing in 2007, mountaineers took to the trails in search of the wreckage. The biggest problem was that in the vast mountain range, rescuers didn't know where to begin their search.

Westergard had an inflatable, tethered solution. To point rescuers toward the most likely crash sites, Westergard and his team designed a nine-part panoramic camera, and loaded it onto a balloon to help with the search.

"We called the payload Nine-Eye," Westergard says. "When you pull a remote trigger, nine cameras shoot in a starburst pattern and capture a complete spherical panorama, with no blind spots."

Although the wreckage of Fossett's fatal flight didn't turn up until many months later, the Nine-Eye camera is still in operation. "It works great," Westergard says. "In fact, that's what we had flying above New York City the other day."

A New Push for Missile-Proof Planes—But Can We Afford Them?

The Malaysia Airlines Flight 17 attack proves that no airliner is completely safe, even at 33,000 feet.

By Barbara Peterson
A Palestinian militant carries a Man Portable Air Defence System (MANPAD).
Mahmud Hams/AFP/Getty Images
July 28, 2014 8:00 PM Text Size: A . A . A
In an increasingly dangerous world, should commercial airlines equip their fleets with technology capable of thwarting a missile attack?

In the wake of the downing of Malaysia Airlines Flight 17, several members of Congress are proposing they do just that. Despite the enormous expense, estimated at up to $2 million per plane, the shootdown in eastern Ukraine has put the idea on the front burner.

The targeting of MH17 was likely a mistake; Russian-backed rebels in the area had already shot down several Ukrainian military jets and were probably trying to do so again. Still, many dangerous conflict zones lie under well-traveled commercial flight paths. The threat to airliners seemed to deepen when the FAA briefly banned U.S. planes from landing at Ben Gurion Airport in Tel Aviv, following a rocket attack that came close to the airport’s perimeter.

As a result, Sen. Charles Schumer and Rep. Steve Israel, both Democrats from New York, called on the FAA, DHS, and the Pentagon to study technologies that could protect airliners and to recommend the best technologies available to repel both portable shoulder-fired missiles, or MANPADS, and the more powerful type of anti-aircraft missile that attacked MH17.

"An attack on a civilian aircraft remains a significant threat," Israel said in calling for the study. Of the estimated 500,000 to 700,000 MANPADS around the world, he said, several thousand are believed to be in the hands of terrorists or other non-state actors, and they’re available on the black market for as little as $5,000.

Systems for protecting airlines have also been around for a while—they’re just expensive. Northrup Grumman, for example, has developed the Guardian anti-missile system that is in use on some military aircraft such as the Air National Guard’s KC-135 aircraft, and has been tested on FedEx cargo planes. The system, which fits in a pod mounted on the underside of the aircraft’s fuselage, uses an ultraviolet missile warning sensor to detect an impending hit. It uses a laser to jam the missile’s guidance system.

Other systems in use include one developed by Israel’s Elta systems, known as Flight Guard, which was deployed on civilian planes after a failed MANPAD attack on an Israeli charter flight off Mombasa, Kenya. The system uses Doppler radar to detect incoming heat-seeking missiles, which it fends off by firing flares that act as decoys to throw the missiles off their intended targets. However, the flares themselves were considered to be a fire hazard, and subsequently Israel backed a laser-based jamming system for civilian use.

Some aviation experts point out that there are other more economical ways of protecting planes from MANPADS, which, due to their low range, are mainly effective against aircraft landing or taking off. Raytheon, among others, has developed anti-missile systems to protect airport perimeters. Vigilant Eagle, Raytheon’s system, combines an antimissile warning system with a high-powered microwave that can knock a shoulder-fired missile launched at an airplane off course. Other ideas include routing aircraft to avoid flying low in certain areas right outside of the airport’s boundaries, so someone with a MANPAD never gets in range for a show.

As for the powerful type of surface-to-air missile that destroyed MH17 at 33,000 feet, the response by most airlines and countries is to reroute aircraft around any area that might have weapons capable of reaching targets at that altitude. Such attacks were considered highly unlikely before MH17, but now they cannot be ruled out.

This Is What's Inside an Airship

Wondering how lighter-than-air ships steer and stay aloft? Take a look at the guts of the new Aeroscraft.

By Kalee Thompson
January 1, 2014 6:30 AM


The Aeroscraft uses a buoyancy system called COSH, for Control of Static Heaviness, which is inspired by submarine technology. The system eliminates the need for runways and ground crews. That could make this airship ideally suited for moving heavy cargo to remote locations.

BUOYANCY


Aeros's first planned production model will have 18 helium tanks (1). To increase lift, the pilot releases helium, which is much lighter than air, from the tanks into the large envelope (2) that makes up most of the volume of the ship (cargo hold not shown). This applies pressure to the four large air bladders (3) located along the sides of the Aeroscraft.

As the bladders are squeezed, much of this air is expelled to the outside. The overall density of the Aeroscraft decreases and the ship rises. To descend, the pilot reverses the process. Three powerful compressors (not shown) force the helium from the envelope back into the storage tanks. A partial vacuum develops inside the envelope and the airbags expand, pulling in dense air from outside the ship. The Aeroscraft sinks. (The transfer of air is assisted by a system of fans and valves.) In flight, the Aeroscraft's shape helps it de-velop some additional lift, but this is not needed for takeoff and maneuvering.

Airship of Dreams: Lighter-Than-Air Travel Is Back

With technology borrowed from submarines, a scrappy California company is attempting to resurrect a century-long dream of building huge airships to carry freight—and people—across the skies.

By Kalee Thompson
The Aeroscraft prototype, seen here in its hangar in Tustin, Calif., could herald a new era in airships.
Nathaniel Wood
January 1, 2014 6:30 AM Text Size: A . A . A
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On a Thursday morning last January a team of engineers gathered in a hulking concrete hangar in the Orange County suburb of Tustin, Calif. The hangar—once used to house massive antisubmarine blimps that patrolled the coast during World War II—was an imposing sight, an anachronism amid the manicured pods of suburban town homes and outdoor malls nearby. The vehicle inside, the prototype for an airship known as the Aeroscraft, was just as much of a spectacle: 266 feet long and 110 feet wide, with a rigid aluminum and carbon-fiber skeleton covered by a thin skin of shimmery mylar composite material. Squat and bulbous, the craft looked like a majestic whale shark, a gentle giant of the seas.

A few of the engineers crowdedinto the compact glass-and-aluminum cockpit suspended below the hull. At the push of a button, the imposing airship lifted from the concrete, becoming airborne for the first time. It rose 10, 20, and finally 35 feet in the air. Then engineers shifted the ship into descent mode and the Aeroscraft settled back to the floor.

The January test was modest: The engineers called it a first float rather than a first flight. The first test outside the hangar, which occurred in early September, after a necessary Federal Aviation Administration certification was granted, was perhaps less ambitious—the ship remained tethered as it rose about 20 feet in the air. But the vision behind the Aeroscraft is expansive. Its inventor, Kazakhstan-born engineer Igor Pasternak, has dreamed since childhood of building huge airships that would crisscross the skies ferrying freight. He is just one in a long line of believers, stretching back at least as far as the German Count Ferdinand von Zeppelin, who built the first rigid airship in the 1890s. "That idea has been around for over a hundred years," says John Hansman, a professor of aeronautics at Massachusetts Institute of Technology and the director of the university's International Center for Air Transportation. By the mid-20th century, lighter-than-air craft had completed more than 150 trans-Atlantic passenger trips. During World War II American airships carried supplies, bombs, even planes. But then the technology stalled—for good reason, Hansman says. "Once airplanes could make long-range flights and carry a lot of payload, the market quickly shifted."

Today most lighter-than-air ships, or aerostats, are blimps—basically oversize balloons that serve primarily as flying billboards. However, the dream of rigid airships carrying freight refuses to die. In the past decade no fewer than a half-dozen companies have invested millions toward the goal. So far they have little to show for it. But Pasternak and his partners believe they will succeed where others have failed, thanks mainly to the Aeroscraft's innovative buoyancy system. Tony Tether ran the military's DARPA (Defense Advanced Research Projects Agency) program from 2001 to 2009 and now serves on Aeros's advisory board. "It's as big a deal as Kitty Hawk," he says without irony. "This will change the way we deliver cargo, and maybe people, around the world."

When I visited the Tustin hangar in May, the Aeroscraft was skinned like a fish. The flexible composite exterior draped the lower frame, while, above, the complex skeleton and a row of car-size helium tanks were left exposed. The tanks lie at the heart of the Aeroscraft's buoyancy system, which is based on submarine technology. One of the lead engineers, 32-year-old Tim Kenny, walked me through it. Submarines draw in seawater to descend, then pump it out to increase buoyancy and rise toward the surface. The Aeroscraft works the same way, he explained, but it uses air rather than water.

Kenny showed me one of the tanks. Empty, it weighed 500 pounds. Right now, filled with helium at low pressure like a child's balloon, it needed an anchor. I was able to push the huge melon out of place with two fingers. Once it is pumped full of highly compressed helium, Kenny explained, each tank becomes far heavier, like a full propane tank for a backyard grill.

Next Kenny pointed out several large, white expansion bladders. When the airship's helium is compressed inside the tanks, a partial vacuum develops around the bladders, and they fill with air from outside the craft. Buoyancy drops and the ship descends. "Once the tanks release that helium back into the main envelope, the expansion bladders deflate to neutralize the internal pressure of the airship and force the air—the ballast—outside the aircraft," he said. The ship rises.

Conventional airships need to take on ballast (typically water) after delivering their cargo to compensate for the lost weight. They need ground crews and runways, though much shorter ones than an airplane uses. An operating Aeroscraft would require none of that—or any ground infrastructure at all. The machine could fly to a roadless region in the Arctic, settle down on the tundra to unload mining equipment from its huge cargo compartment, and take off again on its own. It could deliver immense wind turbines slung below its hull and hover like a helicopter while bearing loads normally associated with ocean freighters.

The biggest challenge in achieving this capability has been the buoyancy system's weight—the heavy tanks, pumps, and hull structure. "People did not believe you could do all of that and end up with something that could float," Tether says. To solve the problem, Aeros engineers became obsessive ounce-watchers. During my tour Kenny handed me a 6-foot piece of carbon-fiber and aluminum truss, the material that makes up the airship's skeleton. It was disconcertingly light.

Even MIT's Hansman, who remains skeptical of the airship industry's future, believes the technology could work. "It's definitely possible. There are no physics that would prevent them from doing what they want to do. It's just hard—hard technically, in terms of financing and having the persistence to get there."

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