Joint MultiRole Bell Valor

Joint MultiRole Bell Valor

WASHINGTON: Want to see an advanced helicopter fly faster than 230 knots? Well, don’t get out your binoculars and cameras yet, aircraft-watchers.

What may be the next great leap forward in rotorcraft technology begins a month from now with a baby step. By early August, the Army-run Joint Multi-Role Technology Demonstrator program is to choose which of four industry competitors will be given money to build a proof-of-concept aircraft incorporating new or exotic means of making rotorcraft fly faster and farther. The JMR TD is one part of a larger Future Vertical Lift program whose goals include producing a new medium-lift rotorcraft able to fly faster than 230 knots – a hundred knots or so as fast as most existing military helicopters cruise.

While the JMR TD aircraft are to start flight demonstrations in late 2017, any actual military aircraft they might help spawn will fly no sooner than a decade or more later, and probably 2035.

“We’re not building prototypes,” the Army program manager, Dan Bailey, told a CSIS panel discussion on the project Tuesday. “They’re demonstrator aircraft.”

JointMultiRolerotorcraft AVX concept

Michael Hirschberg, executive director of the American Helicopter Society International, said that while speeding up rotorcraft flight is a key goal, speeding into production isn’t. “This isn’t as much about urgency as it is about doing a next-generation design,” Hirschberg said. “They’re trying to do it as quickly as possible but it’s practically impossible to do something faster because of how bureaucratic the defense acquisition system is. In any event, it’s better to take a little longer to have something that’s revolutionary than just another evolutionary step.”

Bailey was vague about precisely how the four entrants will be narrowed down, whether two or three will be left standing, and exactly how the money might be divided among them. The Army gave the four entrants – AVX Aircraft Company, Bell Helicopter Textron Inc., a team formed by Boeing Company and Sikorsky Aircraft Corp., and Karem Aircraft – $6.5 million to refine their designs over the past year, and Bailey said they all have technologies he hopes they will continue to develop. With a total of $350 million to spend on a program that began in 2009, he just can’t pay them all to build demonstrators.

“We will certainly — at the end of the day I believe — have opportunities in every one of the four vendors that we would like to continue at some level,” Bailey told reporters after the panel discussion, which featured representatives of each competitor. “Where we draw the line is going to be based on the resources I have to invest.”

Sikorsky Boeing Joint MultiRole JMR-FVL

The four entrants are offering variations on two basic concepts designed to overcome the inherent limitations on a conventional helicopter’s speed imposed by the aerodynamics of rotors, the central challenge being to maximize horizontal as well as vertical thrust. One such concept is the compound helicopter, which adds separate means of horizontal thrust, as Sikorsky did with its X2 technology demonstrator. The other is the tiltrotor, which uses rotors to provide both forms of thrust, swiveling them upward to fly like a helicopter and forward to fly like an airplane, as does Bell-Boeing’s V-22 Osprey, in service with the Marines and Air Force.

AVX and Boeing/Sikorsky are offering compound helicopters while Bell and Karem are offering tiltrotors.

Industry insiders are certain the Army will keep funding at least one of each – at least one compound helicopter and one tiltrotor. Logically, they add, the fact that both AVX and Karem Aircraft are essentially design companies with no production facilities of their own while Bell and Boeing/Sikorsky are major manufacturers of helicopters and the V-22 suggests two most likely outcomes.

The Army might give most of what money it has for the project to Bell and the Boeing/Sikorsky team because they clearly know how to build aircraft and have built aircraft with configurations similar to those they’re offering for JMR TD. Alternatively, on the theory that Bell and Boeing/Sikorsky need the money less, and will probably keep working on their technologies in any event, the Army might give most of the money it has to AVX and Karem to keep them going with designs most experts agree are innovative. But those are only two of many alternatives, so stay tuned.

Comments

  • bigred8690

    I always get a good laugh when I watch reruns of the 1980s tv show Airwolf, because the laws of physics precluded almost all of what was depicted on that silly program. Besides supersonic flight in a chopper not being possible, the internal empty space plus weapons load plus the drag from the rotors would’ve given Airwolf a range similar to a Nissan Leaf with the A/C on full blast hauling four fat people to work during rush hour in Saudi Arabia in July.
    This is similar but not funny at all. Looking at these three artist’s renderings, I immediately see at least one of three basic problems of physics. The first one–warmed over Osprey–will go down like a lead brick when one of the engines gets taken out since it can’t autorotate. I notice the nacelles point horizontally so the exhaust won’t melt or burn everything under it, but wouldn’t that create a thrust vector to the rear when landing? Isn’t that why this rather obvious trick wasn’t done on the real Osprey? (Any engineers reading this?)
    In the second picture–twin ducted fans–the deadweight presented by the fans would take up a lot of the theoretical payload capacity. That’s why the true helicopter was developed from the original gyrocopter concept, where the rotors and associated engine were deadweight in level flight. Presumably in the second picture, the turboshafts are powering both the rear fans and the main rotors, but still that is a lot of extra weight for a little extra speed that won’t evade a MANPADS missile.
    Number three and number two both share another problem, and that is drag from the main rotors. The faster you try to fly, the more drag, lowers fuel efficiency, decreases range. Unless you try to fold the rotors back and stow them internally–an idea that was thought of decades ago–but then you have internal volume problems since fuel is ideally carried internally to reduce drag but you can’t do that when your main cargo is a bunch of folded rotor blades. (google Sikorsky S-57.)

    • SS BdM Fuhress ‘Savannah

      To me there is no need to get there superfast, bomb the area, arrive when that is through and do the body count, then leave. I know they will say, but where trying to save a soldier and every second counts. That’s the same as we need a fire-engine next door to every house to cut down on the response time. We can’t afford that. Hey a guy in the Army after nam said they told him and the pilots, around 50 of them that even a 2 bladed rotor if you loose one of those rotors you can still get the copter to the ground? Crazy Army, same as this! Maybe a 6 bladed rotor lose one possible but I say even not that, the off balance would destroy you. This guy saw a guy land as the MASH copters, then the commander wanted it put in a different tight place and it was moved but crashed trying to get in there, the pilot crawled away on fire before dying.

  • Norris lurker

    There is an alternative design approach to supersonic rotor craft which has not been tried. This is feasible with a single engine and no thrust vector changes as shown in all of the illustrations that I have seen to date. It also allows autorotation for safe engine out descents. Perhaps designers should be looking at the flight envelope rather than lift transition at low speed. There are also alternative methods of rotor torque elimination than by tail or contra rotating blades. Its not a matter of refining a basic design with small percentage improvements, but one of looking back and asking why do we need that design at all.

    • Mike

      Got a drawing you might want to share?

      • bigred8690

        To explain what Norris is saying:

        Alternative methods of rotor torque elimination = NOTAR.
        See the attached picture of the Sikorsky S-72 research prototype from the 1970s. This is the basic idea that Norris is talking about: an aircraft that has spinning rotors that then lock rigid to act as wings. If they were rotating, they would be draggy like propellers and preclude transonic speed (the basic reason why Airwolf is impossible). It’s one of those ideas that can theoretically work; whether it’s worth doing is another question and funding was cancelled.

        • Mike

          Thanks Red,
          Every time I look at the V-22, I find myself wondering if there wasn’t a better way… :(

  • Mike

    Gary,
    If you are still reading this site, sure would appreciate your opinion based on years of experience with helicopters as relates to this article.
    Mike

  • originalone

    Goodness, considering the time span noted in the article, this present course is another waste of $$$$ that the M/I complex uses to fleece the taxpayer[s]. Can’t say that they are resting on their laurels of the past boondoggles, just refreshing the original with new sugar coating, spread a few $$$ into the congress PAC fund, viola, the return on the $$$ spent = $$$$$$ profit. What better way to extract, while looking patriotic at the same time?

  • Mitchell Fuller

    The real issue is an old agreement between Army and Air Force that doesn’t let Army fly planes (Key West Agreement 1948 / Johnson-McConnell Agreement 1966) and when they tried Air Force took them away, examples the Caribou in Vietnam, the Spartan during current operations. This agreement has cost lives and taxpayers money as Army tries to work around this limitation (and AF takes on aircraft $$ it doesn’t want or support and unloads them on ANG, AFR [See A7], or ships them brand new to boneyard [see Spartan] and or constantly tries to retire them [see A-10 ]).

    Give the Army STOL planes for logistics and CAS planes for troops in contact support, this would both save lives and money.

    • Mike

      Well said!…..

    • ycplum

      I made the argument that the equipment should be based on mission, not along technical lines. The Army should be free to have anything involved with theater and battlefield logistics and CAS. Air Force can have all airspace control, strategic and theater bombing, and logistics down to and including theater level. Whether it is fixed wing, rotary wing or antigravity, it shouldn’t matter.