N WJ OURNAL OF NATIONAL GUARD ENLISTED PROFESSIONALS SPRINGSPRING 2014 2014 PATRIOTEANGUS REGIONAL NEWS Sub-zeroFRONTIER training, MILITIA new BradleyThe beginnings FVs and of a youth mentoringMontana’s Nationalmodel adopted Guard WASHINGTONREGIONAL NEWS WATCH MeetFighting the firesnew andDirector floods ofin America’sGovernment heartland Affairs SERGEANTA NEED FOR PALAZZO SPEED With twice the speed and maneuverability of any rotorcraft GOEScurrently in use,TO Sikorsky’s WASHINGTON next-generation X2 design will Asbring the new only capabilities enlisted Guardsman to the National in Congress, Guard Rep. Steven Palazzo has a unique perspective on the National Guard EAN-020 Alexandria, VA 22305 VA Alexandria, PERMIT NO 1984 NO PERMIT BOLINGBROOK IL BOLINGBROOK 3133 Mount Vernon Ave Vernon Mount 3133 PAID US POSTAGE US EANGUS.ORG Enlisted Assn Natl Guard of the US the of Guard Natl Assn Enlisted NON-PROFIT PE U R S WITH TWICE If Superman were a helicopter, he’d be two or more long and fexible rotor one of Sikorsky’s X2-design models. blades. Much shorter rotor blades THE SPEED AND Incredibly fast and nimble, able to attached to an anti-torque tail rotor perform fight maneuvers and achieve provide directional control. MANEUVERABILITY speeds that no other helicopters can, Sikorsky’s X2 design takes a radi- the X2 design is a blueprint for a cally different approach. Instead of OF TODAY’S new breed of super helos. one main rotor hub, there are now In September 2010, the X2 two—one stacked above the other HELICOPTERS, Technology demonstrator aircraft in a co-axial confguration. Each reached 260 knots—twice the speed rotor hub spins a set of four rigid of a conventional helicopter. The rotor blades in opposite directions. SIKORSKY’S NEXT- National Aeronautic Association hon- This counter-rotating co-axial setup ored the achievement with its highest provides the same lift, hover and GENERATION X2 award, the Robert J. Collier trophy. forward fight characteristics of a Sikorsky engineers are currently conventional helicopter, but without DESIGN IS developing the X2-confgured S-97 the need for an anti-torque tail rotor. Raider light tactical helicopter. This In place of that tail rotor, Sikorsky THE CATALYST new 11,000-lb aircraft, Sikorsky has added a pusher propeller for believes, will one day fnd its way fast acceleration to high speeds, or FOR A NEW ERA into the Army’s aviation inventory equally fast deceleration. Another to fll the Armed Aerial Scout (AAS) signifcant difference is the use of IN ARMY requirement to replace the OH-58 composite, rigid rotor blades. With Kiowa Warrior scout helicopter. little fex along a blade’s length, the AVIATION. two rotor hubs can be sandwiched IT’S ALL IN THE DESIGN closer together for reduced drag By Matt Alderton So what’s special about an X2 and incredible maneuverability. aircraft? An X2 aircraft will be able to per- “Helicopters are very useful vehicles, form a 3G maneuver at high speed, but they’ve always had a problem: accelerate and decelerate at level They don’t go as fast as conventional body attitudes, fy backwards from airplanes,” says Sikorsky Aircraft Corp. a hover, pirouette around a target, Director of Engineering Sciences Steve hover at a nose-up or nose-down Weiner, the X2’s chief engineer. “The angle to keep guns on target, climb difference between an X2 and a con- ridge lines with ease at nap-of-the ventional helicopter is the ability to go earth heights, hover at 10,000 feet faster, farther and, in doing so, expand in 95°F, and cover twice the distance the whole operational envelope of a without refueling. conventional helicopter. That’s what Turn off the pusher prop, and the we’re trying to do.” aircraft reduces its acoustic signature Conventional helicopters feature by half. “When you disengage the a single main rotor hub spinning prop, the aircraft’s acoustic signature 12 | NEW PATRIOT | SPRING 2014 The Sikorsky S-97 Raider, depicted here in a graphic illustration, will soon be a reality. Currently in final assembly, the prototype's first flight is planned for late 2014. (Photo illustration courtesy of Sikorsky) EANGUS.ORG | 13 CONVENTIONAL HELICOPTERS SIKORSKY’S X2 (Artist renderings not to scale) 3 1 1 3 2 2 1 Single main rotor hub. 1 Co-axial configuration of 2 Rotor blades designed from two sets of four counterrotat- composite, rigid materials allow 2 Two or more long, flexible rotor blades. ing rotor blades provides the hubs to be sandwiched closer significantly improved together, providing superior 3 Anti-torque tail rotor for directional control. performance while providing maneuverability and performance. the lift, hover and forward flight characteristics of a conventional 3 A pusher propeller replaces helicopter without the need the tail rotor for fast acceleration for an anti-torque tail rotor. and deceleration. X2 TECHNOLOGY VS. CONVENTIONAL HELICOPTERS HOVER ALTITUDE ......150% INCREASE ENDURANCE .............100% INCREASE MISSION SPEED ........100% INCREASE TURN RADIUS ...........50% REDUCTION goes way down, so in a combat zone which time they few as many as 80 it was funding. The Army needed you can hover quietly and cover hours a month, the aging Kiowas a new breed of helicopter, but it the troops,” says Sikorsky Director are winded. At press time, the Army lacked the budget to fnance one. of Flight Operations and Chief Test had proposed eliminating the Pilot Kevin Bredenbeck. “If you Kiowa Warrior feet—to be replaced SO MANY CAPABILITIES were to land at a roadside accident, in the scout role with Apaches. Sikorsky invested approximately or a hospital, or on an oil rig, Sikorsky predicted the need for a $50 million to take the X2 disengaging the prop will ensure next-generation helicopter design Technology demonstrator aircraft someone walking around the rear a decade ago. In 2004, its then- from idea (in 2005) to 250 knots of the aircraft doesn’t run into it.” president Steve Finger ordered a fight speed (in 2010). Although study of previously tested internal it featured the same rigid coaxial NEXT-GENERATION technologies. When the Kiowa and rotor system as the XH-59A, the X2 AVIATION other aging rotorcraft—including demonstrator actually improved Early on in Operations Iraqi and the Army’s utility and attack upon it with all-composite blades Enduring Freedom, the Army had a helicopters, the Black Hawk and that provide double the lift-to-drag moment of reckoning: As it executed the Boeing AH-64 Apache, respec- ratio as the XH-59A. Other key aerial missions in Iraq and Afghani- tively—reached the end of their design features included a low-drag stan, it realized its feet of Kiowa lifespans, he wanted Sikorsky to be fuselage shape; an active vibration helicopters was getting old. ready with successors. control system; fy-by-wire controls, A scout helicopter often dubbed “We started out looking at a whole which reduce pilot workload by the “pointy end of the spear,” the bunch of advanced concepts for high- replacing manual fight controls Kiowa is an armed reconnaissance speed vertical-takeoff vehicles,” recalls with digital ones; and, instead of aircraft that has served the Army Weiner. “Among those vehicles was a the jet engines used for propulsion well since its inception during the helicopter we’d built in the 1970s on the XH-59A, an effcient six- Vietnam War. The latest model, the called the XH-59A Advancing Blade bladed rear pusher propeller that OH-58D, entered service in 1985 Concept Demonstrator.” provides superior thrust. and ceased production in 1989, When Weiner and his team The sum of these features isn’t making the current feet between revisited the XH-59A, they realized just greater speed, but also better 25 and 29 years old—hardly that technological advancements maneuverability and enhanced ancient, but in airframe years since the ’70s could solve the proto- hover capability. For both the decidedly middle-aged. Now, after type’s shortcomings. The problem, active-duty Army and the National more than 10 years at war, during then, was no longer physics; rather, Guard, which eventually could 14 | NEW PATRIOT | SPRING 2014 XH-59A Helicopter utilize attack, rescue and utility variants (Image courtesy of Sikorsky) of the X2, the mission implications are powerful. Consider, for example, the fact that the X2’s pusher propeller features pitch control; that allows the helicopter to change its orientation while hovering, which could be advantageous for delivering weapons to troops in combat, or to landing in sloped conditions for the purpose of search and rescue. Ultimately, though, all roads lead back to speed. “When there are FORM FOLLOWS FUNCTION domestic crises like hurricanes and The predecessor to the X2, the XH-59A utilized a rigid coaxial rotor system to alleviate a problem fres, the National Guard can respond known as retreating blade stall. In conventional helicopters, the blade spinning in the direction of quicker with this aircraft,” Bredenbeck flight is called the advancing blade; the one on the opposite side of the aircraft is the retreating continues. “Or, there’s a medevac blade. Forward motion during flight reduces airflow over the retreating blade, which is necessary mission; think about what this aircraft for lift; the faster the helicopter goes, the more airflow is reduced. To compensate, the retreating means in terms of saving lives. It just blades need a steep blade angle to produce enough lift to keep the aircraft level. At a certain point, opens up so many capabilities.” the angle is so great that it becomes counterproductive, compromising lift and stability. This is called stall, and it’s the reason conventional helicopters are limited to low speeds. WHY GO IT ALONE? The XH-59A solved retreating blade stall with a system of two rotors—one on top of the other— Sikorsky is not alone in their belief that spinning in opposite directions, the advancing blade on each side providing balanced lift at any the X2 design is revolutionary.