Technology Will Make Rotorcraft Faster, Safer

The Pentagon’s investment in rotorcraft science and technology has decreased dramatically over the past 25 years, but companies have been tinkering around in their own shops trying to fill innovation gaps.

Industry representatives say that the next generation of military helicopters will be safer and more efficient. And no matter what shape the rotorcraft take, another thing is certain: They will be faster.

Sikorsky plans to build two prototypes of what it calls the S-97 Raider in the next few years. They will be based on the company’s X-2 demonstrator that reached cruise speeds of 250 knots during a recent flight. The aircraft will feature a General Electric turbo shaft engine, coaxial rotors and a six-bladed push propeller at the tail. The prototypes will weigh 9,000 pounds and may be able to use a more powerful engine being developed under the Army’s improved turbine engine program. They are being designed so they can carry one or two pilots, or none. Sikorsky plans to fly one of the prototypes in 2014, about the time the Army is scheduled to request bids for its Armed Aerial Scout program. The Army’s OH-58D Kiowa Warrior’s service life ends in 2025.

“The calendar is fairly unforgiving,” said Chris Van Buiten, director of innovation at Sikorsky. If the Pentagon wants a new next-generation rotorcraft to replace the Kiowa Warrior, then industry should already have begun maturing the technology for it about five years ago, he said. Otherwise, “the aircraft you end up with in 2025 is pretty much the same as what you’ve got now.”

Bell Helicopter officials believe that they already have pointed the way forward with the V-22 Osprey, which the Marines and Air Force have been using in Iraq and Afghanistan.

“The tilt-rotor is a game-changer,” Bell’s executive vice president of engineering, Jeff Lowinger, said during a speech at the recent Helicopter Association International exposition in Orlando.

In an interview with National Defense, Lowinger said that the V-22 has allowed marines to do things in battle they could never do before. “They never really knew what they were missing and now that they’ve got them, they’ll never go back,” he said.

Marines are currently using MV-22s in Afghanistan and off the coast of Libya, where they were deployed last month to recover the pilot of a crashed F-15, spokesman Capt. Brian Block said. They have relied on the Osprey for tactical movement of personnel in and out of combat, medical evacuation, logistics transport, raids and other activities. The speed and range of the aircraft have allowed it to cover the entire theater of operations, something that the CH-46 cannot do, Block said. Despite its high operational tempo, the Osprey has the lowest mishap rate per 100,000 flight hours of any tactical Marine Corps rotorcraft, he added.

Bell late last year responded to an Air Force information request for a future heavy lift aircraft. The company, along with its V-22 partner Boeing, had been studying the concept of a quad tilt-rotor, which would feature four sets of prop-rotors as opposed to the two that are on the V-22. It has also looked into a more conventional tilt-rotor design. All of these ideas are spiraling into what Bell sees as the next-generation tilt-rotor, said Lowinger, who also oversees work at Bell’s Xworx prototyping facility in Fort Worth, Texas.

European companies are positioning themselves to sell their products to the U.S. military as well. Their work bears the same hallmarks as that of their American competitors. In fact, Italy-based AugustaWestland is working on a light tilt-rotor with Bell, the BA-609. The aircraft would have a maximum cruise speed of 275 knots, officials said. They consider the BA-609 a match for the Coast Guard and for military surveillance, transport and medical evacuation missions.

“In 50 years, a lot of aviation will be this kind of machine,” said Emilio Dalmasso, executive vice president of sales at AugustaWestland. “One that has the capacity to take off and land like a helicopter but then fly as an airplane.”

Eurocopter is taking an approach similar to that of Sikorsky in preserving a more traditional helicopter design. The French outfit similarly is calling its developmental helicopter the X-3, or X-cubed. The company will spend $1.7 billion between now and 2015 on research and development of next-generation aircraft, said Marc Paganini, CEO of Eurocopter’s U.S. subsidiary. It will have a product ready for the market that delivers increased speed and noise reductions at a lower cost, he said.

“If you want to go fast, it costs a lot of money,” Paganini said. “We’re trying to make sure we give the customer something that’s affordable.”

Eurocopter has been working on X-3 for about two years. Like Sikorsky’s X-2, the aircraft features coaxial rotors, but it employs wing-mounted propellers. It reached 180 knots during a recent test flight. Paganini said that the aircraft soon would be able to reach a speed of 220 knots, still slower than the X-2 demonstrator. Eurocopter hopes to make up for any difference in speed with life-cycle cost savings, officials said.

Eurocopter also is working on an X-4, though the company is not saying much about what that future aircraft will entail. CEO Lutz Bertling told reporters at the exposition that X-4 would introduce a completely new way of flying. He said that his firm was working with propulsion and avionics suppliers to make an environmentally friendly and safer aircraft. Its technologies are currently at a low maturity level. The X-4 will have a completely new kind of configuration, Bertling said. “The cockpit as we know it today will not be there,” he said.

Blades also may undergo drastic alterations. Manufacturers are looking at rotor blades and how they could change shape during flight, the same concept behind airplane flaps used for takeoff and landing. Sikorsky is working with the Defense Advanced Research Projects Agency on developing technologies that would make a helicopter “smarter” and allow for blades to adjust in brown-out situations during which flying dust and sand restrict a pilot’s visibility. The research could result in blades for the next generation of rotorcraft, as well as retrofits for the current fleet, officials said. Bell also is exploring advanced blades that may use active flaps or pitch links to reduce vibration, as well as morphing blades to optimize performance during hover and forward flight.

AugustaWestland stumbled on a happy accident when investigating new technologies under the U.K.’s British Enhanced Rotor Program, which is developing blades with an extreme twist and paddle on the end of it that allows for extra lift. An unplanned benefit of the blades may be that they reduce — and in come cases — eliminate brown-out conditions, as well as visibility disruptions caused by snow or fog, said Dan Hill, AgustaWestland vice president of strategy and federal business development.

Helicopter mishaps are second only to improvised explosive devices in causing deaths in theater, he said, so AugustaWestland now is studying with University of Maryland engineers to determine how much of the brown-out benefit actually comes from the enhanced blades and how much can be attributed to the shape of its sleek aircraft.

Hill said that AugustaWestland, which has a facility in Philadelphia, is interested in filling technology gaps in the U.S. military’s fleet of rotorcraft with off-the-shelf systems. Despite recent outcry about the lack of from-scratch helicopter designs, Hill doesn’t see the market shifting more toward new airframes.

“I’m not seeing a lot of evidence of clean-sheet designs,” he said. “What we see as an opportunity is working with the Pentagon and the services to see what’s applicable to current missions and to find ways to take that technology off the shelf. I don’t know that it necessarily needs a clean sheet every time, especially when you’re already 30 years behind.”

Bell is working to enhance technology that will allow its rotorcraft to operate in hotter climates and higher altitudes. This means reducing the weight of aircraft and employing more powerful engines. Company officials remain confident in the V-22 Osprey and will use its operational experience to inform its next generation of tilt-rotors, Lowinger said.

Sikorsky officials also plan to investigate what it may be able to do with tilt-rotor technology.

“We are looking at a very broad set of options,” Van Buiten said. “They range from the lowest risk, lowest cost and significant enhancements to what they already have all the way up to new stuff like X-2.” Tilt-rotors may be a better fit for certain missions, he acknowledged.

“We’re extremely bullish about being able to offer some game-changing options,” Van Buiten said. “And we’re getting ready by spending our own money and working in collaboration with the government.”

The Defense Department has taken some steps in the right direction, experts said. Last year it formed the Vertical Lift Consortium with industry to investigate the future of military helicopters. The group, which includes representatives from major manufacturers and several academic institutions, aims to advance technologies after a dry spell of sorts during which the Pentagon has focused mostly on modifying old choppers.

Sikorsky has bid on a contract to study the feasibility and concepts for the Joint Multirole Helicopter program. The studies will be the first step in shaping requirements for a next-generation Army rotorcraft. “Is it a helicopter, an X-2, a tilt-rotor? This is where we’ll start to understand what the options are,” Van Buiten said.

Companies are optimistic about technologies that could be used in both commercial and military helicopters. Eurocopter officials talk about being able to develop a hybrid chopper using both piston engines and electric motors by 2020. Its parent company EADS is investigating using a combination of diesel engines, batteries, generators and electric motors. A hybrid helicopter could cut fuel consumption in half, officials said. In addition, Sikorsky representatives said they were getting closer to a first flight for its Firefly, a proof-of-concept electric helicopter.

The military needs to move beyond simply putting new devices on old helicopters, and the services must streamline their procurement efforts, experts said.

“The sad fact is that the American military services have allowed the U.S. Army to be the primary procurement agency for helicopters when there are strong divisions within the Army about the priority the helicopter should receive,” said Walter Boyne, a retired pilot, former director of the National Air & Space Museum and author of the book, “How the Helicopter Changed Warfare.”

“There has been a 50-year cycle of failed procurement techniques, resulting in the waste of billions of dollars, while not procuring the necessary and possible advances in helicopter design. As a result, we are remanufacturing 30- and 40-year-old helicopters, ladening them with great new equipment, but not stretching their performance.”

The U.S. helicopter industry needs a leader who can work across all service boundaries, control requirements, balance them against the various needs of the services and see that not too many demands are placed upon a single design, he said.