Conversely, is there any evidence that they'd be more expensive? We're talking a whole new concept here. For some time both in design and in flight testiing, our philosophy has become not so much as to maximize return as to limit risk.
That's a great point about the rotors obstructing launch of weapons from under the wing in cruise.
The extended range of the V-280 was enough for Bell to claim its self deployable, (no need to have complex folding wing) so those stations may only be for carrying its own ammunition to the theater, much like the F-22 ferry droptank + 2 missiles combo was going to work.
from Bell's PR:
*. Significantly smaller logistical footprint compared to other aircraft
*. Strategically Self-Deployable - 2100nm Range
On the other hand, the V-280 (judging from this part of the PR clip) may be fast enough compared to AH-64 in hover mode too. And it's not as if today's helicopters fire only at full speed anyway.
Maybe that missile might have a dual launch mode e.g. like the AIM-120? :-\
1. launch and ignite from a rail.
2. drop/ catapulted under the aircraft and then launch and ignite.
Lock on after launch probably in that case then.
I used on eof the pictures from the site linked by lantinian to check, if the
missiles perhaps would pass the rotor by a whisker, but now I'm sure, that
there's no such chance.
Thought about drop before ignition, too, but as the y are carried in a twin-storey
launcher and AFAIK, this would be a completely new launch mode for something
like a hellfire, I think, here it is just a kind of artistic freedom
It's probably not in the requirements but the illustration above reminded me that of all proposals Bell' is by far the most adaptable and would benefit the most by the addition of air refueling capability.
Notwithstanding the quality of the AVX proposals (and the fact that it is made up of many former Bell people), why would the DoD place a contract with a nascent company that has no record of mass-producing any type before when there are other capable and proven contenders with a half-century-long experience of military contracts? I doubt the military and government are very prone to such risk-taking, especially in the difficult economic context.
Does AVX stand any chance at all on JMR? And what of Karem? Is there hope for such new players to ever find their rightful place in the big leagues?
Probably both. If those are all Hellfires, then it looks like it's carrying a total of 24. The wing mounted weapons, though, could only be fired once the proprotors have rotated up sufficiently (not necessarily all the way to vertical) for clearance.
28 (there are two layers of hellfires under the fuselauge). Note that the AVX proposal carries 16 internally (compared to 8 internally and 20 externally of the V-280 concept art).
I don't know Avimimus. I've been staring at that zoom of picture for a while now and rather than a 5th row of Hellfires under the wing the right most white dots seam like a visual artifact of the previous missiles. Zoom very closely and you will see them further up than the others.
It just makes no sence to have 1 custom 2x5 launcher, rather than 2 standard 2x4 ones
What I also don't see is the Hydra rocket pod and its place, under the shadow of the wing there seams to be the white siluette of a Sidewinder missile.
Finally, check the nose. This version does seams to have a refueling boom sticking out in addition to the gun. I have not seen this on any other image of the V-280 online...and I tried
I just opened the original PDF I linked to, zoomed to that actual picture and took another screenshot and increased the exposure of one area of interest.
So it's much clearer now.
- 24 Hellfires ( 8 internal, 16 external)
- 2 Hydra Rocket pods
- 2 Missiles of unknown kind ( a bit short for AIM-9) on the top of the small wings under the shadow of the main one!!!
- 1 Non revolving gun
- Mid-Air refueling receptacle like on V-22!!!
- Extra windows on the side of the fuselage compared to all other PR images of the attacked version > MI-24 like version???
I just opened the original PDF I linked to, zoomed to that actual picture and took another screenshot and increased the exposure of one area of interest.
So it's much clearer now.
- 24 Hellfires ( 8 internal, 16 external)
- 2 Hydra Rocket pods
- 2 Missiles of unknown kind ( a bit short for AIM-9) on the top of the small wings under the shadow of the main one!!!
- 1 Non revolving gun
- Mid-Air refueling receptacle like on V-22!!!
- Extra windows on the side of the fuselage compared to all other PR images of the attacked version > MI-24 like version???
Some of the things noted may just be a function of the marketeers reusing existing artwork and modifying them to fit whatever is being illustrated for this depiction. For example, Vought for its depictions of the USAF A-7F retouched artists' concepts previously used for its pitch to the Navy for the A-7X.
The windows may just be there because they forgot to take them out. Then again, they could be depicting an alternate configuration, where there would also have door gunners. A combination of Hellfire, APKWS, the nose gun and door gunners would be particularly lethal and effective in an urban environment . Then again, these are marketing drawings and should only be considered "representative". After all, since the sensors to be used haven't ben specified yet, the nose shown is somewhat generic.
Regarding the gun, it's not clear whether it can pivot or not. An underside view of the model shows a slot near the aft end of the fairing that may allow for translation at lower speeds (at higher speeds, probably everyone's gun is going to be firing fixed).
The refueling probe is probably detachable since on most missions in this class of a/c it's not going to be needed. Some pictures will depict it, some won't. This pic is probably in the presentation to imply how much this bird can lift and the versatility of the design.
As to tilt rotors... if you look at slide three of the Bell brief they quote a US Army study that says that tilt rotor is the best option for the future. Rather surprising to me as I always found the Army to be very wedded to their current version of the horse...
As to tilt rotors... if you look at slide three of the Bell brief they quote a US Army study that says that tilt rotor is the best option for the future. Rather surprising to me as I always found the Army to be very wedded to their current version of the horse...
Maybe that missile might have a dual launch mode e.g. like the AIM-120? :-\
1. launch and ignite from a rail.
2. drop/ catapulted under the aircraft and then launch and ignite.
Lock on after launch probably in that case then.
Probably wouldn't want to go to that level of complexity and cost making a new version, plus there might be issues if you're flying at 50-100 ft. Besides, it wouldn't be necessary, IMO. Just tilt the proprotors up far enough to clear.
So the white dots are really the spacing between the front and rear set of doors on the bottom of the aircraft. Agree the smaller missile on the side of the aircraft is a generic place holder. I can't imagine Bell thinking the Army would go for a non-flexing gun on an attack rotorcraft, so I'm in the camp that they just don’t show it flexing. In fact, for long range flight I would expect them to stow it to the rear to reduce drag. I agree that everyone is going for simple ($$) so I doubt the missiles under the wings can be launched without the rotors being out of the way, vice fancy changes having to be made to the missile software. The briefing just posted gives a little more visibility on the Army’s study. I am told that the General from Army Aviation briefed slides earlier this year that talked about much longer distances and self - deployment and longer loiter times. The more you make the desires look like an airplane...
I give AVX 30% because of their innovation with their effort. That said I have to agree with the CEO from Bell who said that the fight for FVL would be between the compound (suspect he was referring to X2 technology) and the tilt-rotor.
F-14D - Army helicopters are now routinely flying at altitudes up to ~7000ft. So technically they could drop iron bombs, but USAF Inc., would get really mad and throw a tantrum.
[list type=decimal]
[*]The 1st window that's closer to the cockpit does not correspond in size to the same one on the troop carrying version. Its larger.
[*]The window itself shows complex reflections of a missile and the wing which proves that this is a 3D model rendering and I am fairly certain Bell has different 3D models for each version.
[*]With so much attention paid to the other details, its unlikely that Bell artists will just intentionally "screw up" on such a detail.
[/list] Its more likely that the PR version of the other images we've seen don't show the full proposal being submitted and that Bell may be holding on to some advantages it does not feel will need to boast at this time. Advantages in capability not mandated by the requirements.
This image was part of the original Power Point presentation a the AAAA press briefing. It's possible that it was explained in more details there by the presenter.
The 1st window that's closer to the cockpit does not correspond in size to the same one on the troop carrying version. Its larger.
The window itself shows complex reflections of a missile and the wing which proves that this is a 3D model rendering and I am fairly certain Bell has different 3D models for each version.
With so much attention paid to the other details, its unlikely that Bell artists will just intentionally "screw up" on such a detail.
Its more likely that the PR version of the other images we've seen don't show the full proposal being submitted and that Bell may be holding on to some advantages it does not feel will need to boast at this time. Advantages in capability not required by the requirements.
This image was part of the original Power Point presentation a the AAAA press briefing. It's possible that it was explained in more details there by the presenter.
I've actually seen this happen, especially in a "minor" shot as background on a slide. To draw a real life parallel, a major work came out in 2011, a 512 page book, "The Age of Airpower". A lot of work and thought went into it, with the author and publisher wanting to present it also as a reference on history and application of airpower.
The front cover of the book is a picture of the F-16CJ. It's printed backwards....
A bit more thoughts on the V-280 Speed and Maneuverability.
In hover mode, the V-280 engines continue to point aft which allows for all the trust to be available for speed and yall maneuvering. In this respect the V-280 is like a conventional helicopter and unlike the V-22 will fly very fast in hover mode. Probably as fast as a conventional helicopter. That is seen here
So I don't see any issues with the underwing pilons being of limited use since the aircraft will more likely transition to hover mode for combat operation anyway. The disadvantage of having the engines stay in horisontal mode is that their trust cannot be used for lift, but that extra lift is only needed on the much heavier V-22.
Because the engines are spaced so far apart, V-280 can turn either very precisely with minimum trust input or very fast. The high turn rate is evident here (right hand side) in the gunship going to overwatch. The disadvantage to this is that a lost of one engine will make the aircraft quite difficult to control.
Some of these concepts have range, ceiling and payloads to the point that could an all internal weapons carriage version be a brand new iteration called the 'Helicopter Bomber' and carry a few JDAMs?
Some of these concepts have range, ceiling and payloads to the point that could an all internal weapons carriage version be a brand new iteration called the 'Helicopter Bomber' and carry a few JDAMs?
Some of these concepts have range, ceiling and payloads to the point that could an all internal weapons carriage version be a brand new iteration called the 'Helicopter Bomber' and carry a few JDAMs?
I don't think that the Army will advertise the ability to bomb, as the USAF Inc., will scream. Especially when the budget is deminishing. then someday an enterprising soldier will figure out how to do this in the field.
I think that the reason both the Sikorsky and the Bell have a resemblance to the H-60 is that there are a lot of mission similarities; side-by-side flight crew, ~11 troops and two crew member.
The V-280 will have cross shafting like the V-22 so the loss of an engine (should) allow the power to both prop-rotors. Most rotorcraft only have residual power from the engines (like 5%) so loss of an engine should have minimal if any affect on the aircrafts controllability.
Some of these concepts have range, ceiling and payloads to the point that could an all internal weapons carriage version be a brand new iteration called the 'Helicopter Bomber' and carry a few JDAMs?
There is no reason an Apache today couldn't carry some 500 lb bombs on its pylons. At least unlike the future JMR internal carriage it would actually have space to carry the store. You won't be able to drop JDAMs from the JAGM sized bays on the JMR proposals because the bomb is too long. Maybe an SDB or two could fit.
Well the US DoD would have judged them as being able to do so in order to award them a developmental contract. They won’t win the contract if they ask for more money to build their JMRs than their rivals. By looking at the comparative conservatism of their design compared to the tilt rotor and more complex coaxial hub of their competitors I would expect they could probably offer a cheaper bid.
Triton said:
If the AVX Aircraft Company concept wins the FVL Medium contract, I wonder how long it will be before the company is acquired by another defense contractor?
Acquisition is a process initiated by the thing to be acquired. You can’t just walk into their office plomb a suitcase for of cash on the table and say “I buy you!” In order to get this far in the bidding process AVX would have demonstrated to the US DoD their capacity to fund a build program for JMRs. So they would not need to sell all of their stock to secure investment. Also after winning a contract they would be plush with potential cash and would want to keep their stock to soak up the dividends.
There seems to be a lot of simplistic assessment of AVX as just another pseudo aircraft builder with only a web presence or hopeless start up all designed to soak up mom & pop investment dollars before going broke. But they are more like Hughes Tools Aircraft Company (later Hughes Helicopters) than a Stavetti with a considerable technical presence and by looking at the detail of their offer a big input from a lot of established aerostructure and aerocomponent builders.
They can win this as much as the other guys depending on if their technical proposal can meet the requirements. Which is a question every bidder faces.
From DefenseTech over at Military.com
Army Details Next-Gen Helicopter Timelineby Kris Osborn on April 25, 2013U.S. Army — Graphic Illustration of potential JMR configurationU.S. Army officials plan to award up to four design contracts by the end of fiscal year 2013 for vendors to build the Joint Multi-Role (JMR) demonstrator aircraft, a next generation helicopter fleet, Army leaders said Thursday.
Current plans call for two JMR technology demonstrator aircraft to be designed and built for a first flight by sometime in 2017, said Todd Turner, director for the Army’s Research and Technology Air Portfolio.
“This is an S&T [Science and Technology] effort for the development of a new, medium-class platform. The goals are to design, fabricate and demonstrate an advanced vertical lift vehicle with a combat radius of 424 kilometers, that’s an 848 kilometer range, un-refueled, at speeds of up to 230 knots,” Turner said at the National Defense Industrial Association’s 14th Annual Science & Engineering Technology Conference/Defense Tech Exposition, National Harbor, Md.
A key goal for the program is to be affordable, and develop an aircraft that can reach much greater speeds and extend mission possibilities without compromising an ability to hover, Turner said.
Army officials said the S&T effort is designed to lower risk, reduce costs and inform requirements for what will be a Future Vertical Lift formal program of record designed to deliver new aircraft by 2030.
“We’re currently completing what we call configuration trades and analysis portions of this effort which will finish this year. The trades we considered were cost, weight and power requirements, mission equipment packages and life-cycle costs. All configurations were considered,” Turner said.
The configurations currently being examined include a tilt-rotor possibility, like today’s Marine Corps and Air Force V-22 Osprey as well as various compound configurations such as air vehicles with a rear-thrusting mechanism and co-axial rotorblades, Army officials explained.
The service is evaluating responses to an Army solicitation to industry to build designs. Service officials plan to down select to two design teams by the fourth quarter of fiscal year ’14, Turner said.
The JMR effort also plans to include next-generation mission equipment and avionics along with integrated sensors and weapons systems.
Turner said Army S&T is working on advanced rotor designs, autonomy algorithms and concept analyses wherein they assess air-vehicle design methods.
“We currently have a good handle on how to build systems when we have a database. What we are trying to do is move towards where we can design new systems at a more rapid pace. Get that design closer to what the air vehicle will look like, he said.
The FVL aircraft is slated to be powered by an Improved Turbine Engine Program (ITEP), a more powerful, 3,000-horsepower, more fuel-efficient engine also being informed by an ongoing S&T Program, Advanced Affordable Turbine Engine effort.
“It’s transitioning out of S&T this year to the ITEP program. It’s showing benefits of 25-percent reduced burn rate and a 35-percent reduction in production and maintenance costs,” Turner said.
Army S&T is also in the early phases of developing the Future Affordable Turbine Engine, a 7,000-horsepower heavy class engine for larger rotary platforms such as the CH-47 Chinook.
“We’re developing material and component technologies for the compressor and turbine sub-systems,” he added.
Some of these concepts have range, ceiling and payloads to the point that could an all internal weapons carriage version be a brand new iteration called the 'Helicopter Bomber' and carry a few JDAMs?
I don't think that the Army will advertise the ability to bomb, as the USAF Inc., will scream. Especially when the budget is deminishing. then someday an enterprising soldier will figure out how to do this in the field.
I think that the reason both the Sikorsky and the Bell have a resemblance to the H-60 is that there are a lot of mission similarities; side-by-side flight crew, ~11 troops and two crew member.
The V-280 will have cross shafting like the V-22 so the loss of an engine (should) allow the power to both prop-rotors. Most rotorcraft only have residual power from the engines (like 5%) so loss of an engine should have minimal if any affect on the aircrafts controllability.
Agree 100% on no Army bombing from an FVL. USAF would scream and work to kill the program. I believe there is actually an agreement somewhere that states that Army rotorcraft may only carry guns or forward firing ordnance.
If you look at the history of the AH-56, USAF didn't complain too much when it was described as only an escort for troop carrying helicopters. They started taking notice and complaining when it was also talked up as doing CAS, and they really went ballistic when some Army folks said that if you put the pusher prop into Beta, it could dive bomb. From that point on, USAF actively worked to kill it, and they might do the same here. In fact, that's one of my worries about the V-280. Proprotors forward, it looks a lot like a fixed wing airplane. I may be paranoid, but I fear the Army might decide that if they pursue that technology AF will fear it treads on their "roles and missions" and lobby against it, so Army won't give it a fair shot.
This issue has nothing to do with JMR. Via internal carriage of stores JMR will have less capability to drop Mk 80 series bombs than current attack helicopters. Just because it has bay doors does not make it a bomber. One of the worse cases of “it kind of looks like therefore it is” theorising on the internet. Maybe we should call these comments “Reddits”.
A bit more thoughts on the V-280 Speed and Maneuverability.
In hover mode, the V-280 engines continue to point aft which allows for all the trust to be available for speed and yall maneuvering. In this respect the V-280 is like a conventional helicopter and unlike the V-22 will fly very fast in hover mode. Probably as fast as a conventional helicopter. That is seen here
So I don't see any issues with the underwing pilons being of limited use since the aircraft will more likely transition to hover mode for combat operation anyway. The disadvantage of having the engines stay in horisontal mode is that their trust cannot be used for lift, but that extra lift is only needed on the much heavier V-22.
Because the engines are spaced so far apart, V-280 can turn either very precisely with minimum trust input or very fast. The high turn rate is evident here (right hand side) in the gunship going to overwatch. The disadvantage to this is that a lost of one engine will make the aircraft quite difficult to control.
I'd thik a more accurate description might be "rotorborne" and "wingborn"e. "Hover mode" tends to sound like the engines only go vertical for hover, but actually they'd stay up until the wing can take on a signficant amount of lift. From the video, it seems this can be fairly rapid. Also, since translation or being at an intermediate point doesn't impose any maneuvering limitations, they can be stopped in between. Granted, this is a semantic quibble.
Almost all of the power of the engines is going to be used to power the proprotors, the residual thrust left in the exhuast I'll wager is not going to be an important factor. I can't see them really expecting to do much with that thrust for yaw when in rotorborne mode, you'll get all you need from the proprotors and not have to put up with the complexity of differential power settings on the engines (which could also engage the crosshaft. Bell has said that they get their high speed as a fallout from the power for the 6K/95F requirement.
Basically, he explains it was because tilting the engines weighed less.
The V-22 is a transport, and great agility at low speeds or the best speed in rotorborne flgiht was not a driver. The idea is to fly as much of your mission as you can wingborne, because that's where you get the best speed and range. No particular reason to fly fast rotorborne, although I'd wager it could match a Black Hawk's cruise speed while in that mode, but it would be inefficient. I do believe the Osprey holds the world speed record with an external load, but in that case the engines were partly tilted.
This issue has nothing to do with JMR. Via internal carriage of stores JMR will have less capability to drop Mk 80 series bombs than current attack helicopters. Just because it has bay doors does not make it a bomber. One of the worse cases of “it kind of looks like therefore it is” theorising on the internet. Maybe we should call these comments “Reddits”.
I do not disagree that the comments about carrying bombs is superfluous. However the points about how the USAF Inc., would react to any perceived threat to its domain are not in my opinion unrealistic to consider.
I have the same trepidation as F-14D that the V-280 may cause angst to both the Army and USAF Inc., due to the potential perception of mission creep. There are numerous precedence of this exact thing happening.
I have the same trepidation as F-14D that the V-280 may cause angst to both the Army and USAF Inc., due to the potential perception of mission creep. There are numerous precedence of this exact thing happening.
Those precedents are not fully replicated because there is no comparable USAF program under threat. The previous cases included Cheyenne vs A-10, C-27 vs C-130 (and even Caribou vs Hercules) and all had some sort of actual or supposed duplication of effort. USAF has nothing that could possibly compete with a Black Hawk replacement and no capacity to offer that kind of scale of service even if they did. Even an attack version of the V-280 with under wing ordnance stores could never be mistaken as a competitor to the F-35. Maybe to the A-10 or a Super Tucano but they are not going to be significant assets in USAF’s future.
Indeed. I actually thought I was posting on that topic, so the moderators should consider moving most of our comments from yesterday that were only related to the V-280 over there.
US furthers next-generation helicopter studies
30 April 2013 - 15:29
by Tony Skinner in London Plans for a next generation US helicopter to replace the AH-64 Apache and UH-60 Black Hawk have moved forward with three different configurations under evaluation.
Further details of the Joint Multirole (JMR) technology demonstration (TD) programme emerged in evidence to the US House Armed Services Committee on 16 April.
Mary Miller, deputy assistant secretary of the Army for Research and Technology, said three different configurations of JMR aircraft had been designed – a conventional helicopter, a large-wing slowed rotor compound helicopter, and a tiltrotor.
‘We are investigating various design excursions to fully explore the size and environmental characteristics of interest to the DoD, including shipboard operations. As part of the JMR TD programme, an industry/government Configuration Trades and Analysis (CT&A) effort… is nearing completion,’ Miller said.
Four companies – AVX Aircraft, Bell, Piasecki Aircraft, and Sikorsky – have been contracted to assist in defining the ‘trade space’ for Phase 1 of the JMR TD air vehicle demonstration.
Two companies are expected to be downselected in September 2013 to design, manufacture and test two air demonstrator vehicles, with first flights scheduled to occur in the fourth quarter of FY17.
‘The JMR TD objectives are to validate critical aircraft configurations, technologies and designs at the vehicle system level, and demonstrate vertical lift capabilities superior to those in the current fleet,’ Miller said.
Earlier this year, Sikorsky and Boeing announced that they will submit a joint proposal for Phase 1, with a design based on the Sikorsky’s X2 Technology rotorcraft design. In April, Bell unveiled its V-280 Valor tiltrotor as a candidate while EADS North America is also likely to have submitted a proposal.
A concurrent second JMR phase is focused on assessing mission systems effectiveness with six companies now contracting to carry out these studies. http://www.shephardmedia.com/news/rotorhub/us-further-next-generation-helicopter-studies/
GKN Aerospace is in talks with Bell Helicopter and Sikorsky about possible involvement in their bids for the US Joint Multirole (JMR) next-generation helicopter project.
Speaking at a media conference in London on 30 April, Marcus Bryson, CEO of GKN Aerospace and Land Systems, said the company had entered dialogue with both companies about providing its composite technology into the JMR/Future Vertical Lift effort.
GKN already provides the CH-53K aft transition fuselage section, cargo ramp and overhead door structural assemblies to Sikorsky. It was also selected to provide metal and composite structures for the new Bell 525 Relentless medium helicopter.
‘You have to keep a foot in both camps but we are having some very good quality discussions with both of them,’ Bryson said.
‘The only reason we are there talking to them is because of our technology. If you look at what we have done with Sikorsky with the CH-53K – that whole aft section of the 53 – we delivered it on time, to cost, to specification.
‘And similarly for the last two years we have been working quite hard to develop a relationship with Bell, which we really didn’t have before.’
GKN’s involvement in the JMR TD programme would centre on its composite technology and self-sealing fuel tanks.
The company has opened a fuel tank facility in Alabama in the US to become an indigenous manufacturer and gain access to the US market and is providing parts to US prime contractors, such as fuel tanks to Bell.
Four companies – AVX Aircraft, Bell, Piasecki Aircraft, and Sikorsky – have been contracted to assist in defining the ‘trade space’ for Phase 1 of the JMR TD air vehicle demonstration. Two companies will be downselected in September 2013 to design, manufacture and test two air demonstrator vehicles, with first flights to occur in the fourth quarter of FY17.
Meanwhile, Bryson explained that the downturn in military budgets in the US and around the world had led the company to increase its civil business in recent years. In 2013 the proportion of civil revenue for the company is expected to reach 70% versus 30% military – an inverse of the balance from five years ago.
‘On the civil side, we are really in the middle of a super cycle of civil aerospace. On the downside are worldwide defence budgets and all countries bar none are cutting back on their budgets. We are beginning to see some impact – although not huge on our company at the moment – but inevitably we don’t see defence as a growth sector for the next four to five years.
‘It is still a profitable sector, it is still a place we want to play, but where we have positioned the company now where 70% of our revenues is on the civil side, is exactly where we want to be.’
Can a small company pull off an upset and win a role in the most important rotorcraft demonstration of this decade? It may face competition from giants Bell Helicopter, Boeing and Sikorsky, but AVX Aircraft believes it can.
More than that, the Fort Worth company argues the U.S. Army, to be true to the intent of its Joint Multi-Role (JMR) program, should pick AVX for one of two high-speed rotorcraft demonstrators planned to fly in 2017.
The stakes are high. The JMR technology demonstration is a precursor to the planned Future Vertical Lift (FVL) Medium program to replace thousands of Sikorsky UH-60 Black Hawk and Boeing AH-64 Apache helicopters from the mid-2030s.
It is a prize so large that Boeing and Sikorsky have teamed for JMR and FVL. They are offering a compound helicopter based on Sikorsky's X2 high-speed coaxial-rotor configuration. Bell is offering a tiltrotor. Even EADS North America has put in a bid, likely based on Eurocopter's X3 hybrid helicopter.
AVX's design (see image) combines coaxial rotors with ducted fans and small wings. It is not the only small player with hopes of winning. Piasecki Aircraft has proposed a winged compound helicopter with a vectored-thrust ducted propeller, as flown on its X-49A SpeedHawk.
Established by former Bell employees, AVX was set up around the coaxial-rotor/ducted-fan concept. The company proposed the configuration to upgrade the Bell OH-58D Kiowa Warrior armed scout, but its breakthrough came when—with Bell, Boeing and Sikorsky—AVX won an Army contract to study concepts for JMR and FVL.
Coaxial rotors provide high hover efficiency and eliminate the power drain of a tailrotor, says Troy Gaffey, AVX president and chief engineer and former head of engineering at Bell. The ducted fans provide propulsion, so the rotors only provide lift, greatly reducing the power required. At the 230-kt. speed sought by the Army, two-thirds of power goes to the fans and a third to the rotors.
Not tilting the rotors to provide thrust reduces blade loads and cuts vibration by at least 50%. “We also fly with the fuselage a little nose-up for lower drag, so we get more speed with the same power,” Gaffey says. “The focus of the configuration is aerodynamic efficiency.” Ducted fans are smaller and lighter than open propulsors, with better cruise efficiency, he says.
At maximum speed, only 60% of lift is from the rotors; the other 40% comes from small forward wings and the aft ducts and stub wings. But, at 230 kt., the Kamov-style rotors generate half the drag—as much as the airframe—so AVX is testing hub-and- mast fairings in a bid to reduce rotor drag by a third.
The high lifting capacity of the 56-ft.-dia. rotors allows the helicopter to carry significant external loads, Gaffey says. As proposed, the aircraft weighs 27,000 lb. carrying 12 troops and four crew, versus 22,000 lb. for the UH-60M. But it can lift 13,000 lb. externally, versus 9,000 lb. for the Black Hawk. “It is more like a Chinook from a cargo standpoint,” he says.
One source of the lifting capacity is the engine power needed to go fast. To fly 200 kt. with the basic 4,300-lb. payload would require 3,100-shp engines, but the target of at least 230 kt. would need more than 4,600 shp. “In the hover, that's a lot of extra power, but a large part of the Black Hawk's mission is lifting heavy loads,” says Gaffey.
All the compound-helicopter candidates face the same problem. “The main issue with 230 kt. is the power in the aircraft. Bigger engines cost more and burn more fuel, but the side benefit is enormous lift margin,” he says. If the Army decides speed costs too much, AVX can remove the ducted fans. “Without fans, speed is in the 170-kt. range.”
AVX has assembled a large team of suppliers to build the aircraft, but why should the Army choose an outlier for such an important program? For Gaffey, it lies in the Army's edict that JMR bidders must show a “compelling need” to fly a demonstrator to reduce risk for FVL.
“We don't see any point in flying another tiltrotor. When there has already been the XV-15 and V-22, what is in Bell's V-280 that needs to fly?” asks Gaffey. “It's almost the same for the X2—they have flown it and it works. And the X3 has been flown by Eurocopter.
“In our case, the coaxial rotors and ducted fans need testing to verify the efficiencies,” he says. “The big manufacturers will probably continue on their own as long as FVL is on the horizon, so we are hoping the Army will keep the little guy in the program to provide a little competition.”
So basically they're saying they believe they should be chosen to build the demonstrator because they are the least experienced and have the MOST risky design? : Sounds like a recipe for a winner to me.
So basically they're saying they believe they should be chosen to build the demonstrator because they are the least experienced and have the MOST risky design? : Sounds like a recipe for a winner to me.
Troy Gaffey didn't say that at all. AVX Aircraft Company can't fund a technology demonstrator like the Sikorsky X2 Demonstrator so it needs help from the United States Army to build one. As for least experienced, you don't think that Troy Gaffey, AVX president and chief engineer, didn't get experience as former head of engineering at Bell Helicopter? If the United States Army is totally risk averse, why bother to increase the rotorcraft performance bar at all?
So basically they're saying they believe they should be chosen to build the demonstrator because they are the least experienced and have the MOST risky design? : Sounds like a recipe for a winner to me.
Troy Gaffey didn't say that at all. AVX Aircraft Company can't fund a technology demonstrator like the Sikorsky X2 Demonstrator so it needs help from the United States Army to build one. As for least experienced, you don't think that Troy Gaffey, AVX president and chief engineer, didn't get experience as former head of engineering at Bell Helicopter? If the United States Army is totally risk averse, why bother to increase the rotorcraft performance bar at all?
How many rotorcraft has AVX produced? They're basically a startup consisting of disgruntled former Bell employees. I don't doubt that they know about rotorcraft but I do question their ability to tackle a program like this. I think their's is the most interesting of the four concepts but I'd put them at the bottom of the list for actually winning this thing.
I have the same trepidation as F-14D that the V-280 may cause angst to both the Army and USAF Inc., due to the potential perception of mission creep. There are numerous precedence of this exact thing happening.
Those precedents are not fully replicated because there is no comparable USAF program under threat. The previous cases included Cheyenne vs A-10, C-27 vs C-130 (and even Caribou vs Hercules) and all had some sort of actual or supposed duplication of effort. USAF has nothing that could possibly compete with a Black Hawk replacement and no capacity to offer that kind of scale of service even if they did. Even an attack version of the V-280 with under wing ordnance stores could never be mistaken as a competitor to the F-35. Maybe to the A-10 or a Super Tucano but they are not going to be significant assets in USAF’s future.
Sorry for the lateness of this post, and don't want to take this too far off topic. What my, and I think Yasotay's, fear is not that a particular USAF system might be threatened. I fear, based on history, that if USAF perceives a system looks like it might threaten its "roles and missions", it could strive to kill that system, even if AF didn't have any particular desire to perform the job itself. For example, you cite the C-27J, but it wasn't Army's intent to challenge the C-130. It was to provide light intra-theater transport in lieu of the CH-47 for those areas where VTOL capability wasn't required. It would be cheaper to operate than the Chinook and would also help to preserve C H-47 blade life. But it was a fixed wing, so that was a no-no. Once Army intimated that AH-56 could do CAS, and especially with the prop in Beta could dive bomb, USAF took that as a challenge and struck back, with lobbying and other tactics. It's often said that this was at least half the impetus behind the A-10.
My concern is that a 280 knot Tilt-Rotor JMR looks too much like a fixed wing and could be perceived as threatening the "R & M".
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U.S. Army — Graphic Illustration of potential JMR configurationU.S. Army officials plan to award up to four design contracts by the end of fiscal year 2013 for vendors to build the Joint Multi-Role (JMR) demonstrator aircraft, a next generation helicopter fleet, Army leaders said Thursday.Sounds like a recipe for a winner to me.
