Sunday, April 14, 2013

The Other JMR/FVL Contenders

Posted by Graham Warwick 

Attention has focused on Boeing teaming with Sikorsky to offer a high-speed coaxial-rotor compound helicopter, and Bell going it alone with a tiltrotor proposal. But they are not the only bidders for the US Army's Joint Multi Role (JMR) technology demonstration - precursor to the planned Future Vertical Lift (FVL) Medium program to replace the UH-60 Back Hawk and AH-64 Apache. There are at least two others.


FVL-M Utility (Concept: AVX  Aircraft)


One is small company AVX Aircraft, comprising mostly former Bell employees. Fort Worth-based AVX is proposing a compound helicopter (above) with coaxial rotors, small wings and dual ducted-fan propulsors. The rotor system is closely modeled on Kamov's coaxial design, down to the spacing between the two rotors, which is much greater than in Sikorsky's coaxial-rotor X2 configuration.

AVX says its design is capable of 230kt, the Army's threshold speed for the JMR flight demonstrators. The ducted fans provide the thrust, offloading the rotors, and at 230kt the forward and aft wings and fan ducts together produce 40% of the lift, with only 60% coming from the rotors.


FVL-M Attack (Concept: AVX Aircraft)

And, at 230kt, half the drag is from the fuselage and half from the rotor system. So AVX has been conducting windtunnel tests of a 50%-scale model of the coaxial hub in a bid to reduce its drag by a third. The rotor system has two composite-flexbeam hubs with drag-reducing aerodynamic fairings on the blade cuffs and the mast between the hubs.

Another bidder is only slightly bigger Piasecki Aircraft, which has a long association with compound helicopters. The company is emphasizing the "joint" in JMR with its PA61-4 Advanced Winged Compound (AWC) proposal. The 233kt full-compound Army variant (below) has Piasecki's signature vectored-thrust ducted propeller (VTDP), flown on the X-49A SpeedHawk, for propulsion and anti-torque and a long-span wing for lift. The wing pivots in pitch for addition flight control and to reduce rotor download in the hover.


Full compound Army FVL-M (Concept: Piasecki Aircraft)

The wing pivots in pitch for additional flight control and to reduce rotor download in the hover. Removing the wing, but retaining the VTDP, produces the 180kt "thrust compound" variant (middle, below), which is better suited to shipboard operations. If increased speed is not a requirement, say for external-lift or vertical-replenishment missions, the VTDP could be replaced with a lighter and cheaper conventional tail rotor to produce the 160kt helicopter variant (left, below).


Concepts: Piasecki Aircraft

The Army has funding to build two competing demonstrators, at most, with Sikorsky/Boeing's 230kt coaxial compound and Bell's 280kt "third-generation" tiltrotor currently leading the field. Eurocopter, through EADS North America will have submitted a strong bid too, likely an X-3-style compound, so AVX and Piasecki would appear to be long shots.

Some suspect Karem Aircraft also may have submitted a JMR demonstrator proposal. Abe Karem designed the A160 Hummingbird with its optimum-speed rotor, and went on to work on an optimum-speed tiltrotor. Karem led one of the teams that worked on conceptual design of the Army's now-defunct Joint Heavy Lift large transport, so a JMR bid is not out of the question.

Read more at:
http://www.aviationweek.com/Blogs.aspx?plckBlogId=Blog:27ec4a53-dcc8-42d0-bd3a-01329aef79a7&plckPostId=Blog:27ec4a53-dcc8-42d0-bd3a-01329aef79a7Post:6424afd0-6286-4079-a4fe-b136a56e6175


Thursday, April 11, 2013

Bell Unveils Third-Gen Tiltrotor Concept

By Anthony Osborne tony_osborne@aviationweek.com
Source: AWIN First




Bell Helicopter says it has taken lessons learned from the V-22 Osprey and is incorporating them into the third-generation tiltrotor it is offering for the U.S. Army’s Future Vertical Lift requirement.

The V-280 Valor, being unveiled at the Army Aviation Association of America convention in Fort Worth this week, is a clean sheet design to meet the Army’s medium-size requirement for as many as 4,000 aircraft in the coming years, replacing both the UH-60 Black Hawk and the AH-64 Apache in the utility and attack roles. In delivering a tiltrotor, Bell is putting its emphasis on speed, range and productivity, claiming the tiltrotor will be twice as productive as the conventional designs and some of the hybrids that have emerged from its competitors.

“Tiltrotor is the most effective, it maximizes the capability through speed and range and as distances increase, that productivity increases,” says Chris Gehler, business development manager for FVL at Bell.

The most obvious change comes in the configuration of the engines. Rather than tilting pods, the engines remain fixed horizontal with the rotor and drive system encased in a tilting pod. According to Bell this eliminates concerns about ingress and egress of troops from the side doors and increases the field of fire for the door gunners when on approach to a hostile landing zone. It may also help lower development risk, reducing the need to certify engine operation at different angles. Bell is working to give the V-280 lower rotor disk loading, which will in turn reduces the level of downwash. The company is confident that the aircraft will have a downwash somewhere between that of the V-22 and a conventional helicopter.

FVL Medium utility variant (Concept: Bell Helicopter)

A key part of the development to reduce cost is to simplify tiltrotor designs compared to the V-22. With this in mind, the V-280 features a straight wing instead of the forward-swept wing of the Osprey. Furthermore, Bell plans to use what it calls Large Cell Carbon Core technology, which allows the wing to be produced in one large piece, reducing weight and manufacturing costs. Critically, the use of the technology will allow any damage to be detected immediately.

As a result, base models of the V-280 will not have the complex wing-folding mechanisms needed by the Osprey for its maritime mission. The aircraft will be able to self-deploy over 2,100 mi. to meet a stipulated need to self-ferry over long distances.

“Make the shift to the Pacific region ... and in terms of what it’s going to be able to do with operational reach and having smaller, leaner forces, it is a key enabler,” adds Keith Flail, director of FVL at Bell.

Bell has illustrated two versions of the aircraft in its briefings at Quad-A: the utility variant capable of carrying 11 passengers and four crew, and an attack variant using the same fuselage that would presumably replace the AH-64 Apache. Artist’s impressions show the attack aircraft being able to carry precision guided weapons in a payload bay as well as under the wings. A turreted gun would fit under the nose.


FVL Medium attack variant (Concept: Bell Helicopter)

With Boeing now working with Sikorsky on providing an FVL solution using Sikorsky’s X2 compound technology, Bell is looking for a new partner with which to share the program. The company says it is in discussions with other “aerospace partners” and that those discussions are continuing, but refused to put a timeline on any announcement.

Also read http://www.aviationweek.com/Blogs.aspx?plckBlogId=Blog:27ec4a53-dcc8-42d0-bd3a-01329aef79a7&plckPostId=Blog:27ec4a53-dcc8-42d0-bd3a-01329aef79a7Post:085f3884-fb49-4997-a479-7cd3a38af7d7

SpyLite mini-UAS






The SpyLite® is a combat-proven, electric, back-packed, extended performance Mini-UAS, optimized to provide covert, “over-the-hill” real-time visual Intelligence to its users; it is specifically designed to allow critical, visual recognition of elements in real-time and gain dominant situational awareness of the inspected area. The system can be carried by 2 men with the overall weight of 20 Kg for each and can fly in almost any weather condition (unique in its ability to fly in strong winds and on cloudy or rainy days, assuring high operational ability and availability). 
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The SpyLite was delivered to customers around the world and is in operational use by the Israeli MOD. 

Operational missions
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"First responder".
Border protection.
Force / convoy protection.
Security operations
Law enforcement.
Search and rescue.
Disaster control and management operations.
Commercial applications.
Mapping on Demand photogrammetric solutions.
 
Advantages
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 Combat Proven covert operation- Thousands of hours accumulated in operations and
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• Performance- unmatched UAV capabilities (up to 4 hour endurance, 50 km operational range).
Superior Payload and imagery capabilities- dual sensor gimbaled and stabilized payload and
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  leveling.
All weather operation – rough weather resistant; Proven operations in rain.
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Specifications
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 Weight ~9 Kg
 Payload  Up to 1.3 Kg 
 Endurance Up to 4 Hr. 
 Operational Range Over 50 Km (Can be extended to 80 Km)
 Best Operational Altitude Up to 1000 m / 3000 ft. AGL
 Ceiling  10000m / 30000 ft. ASL

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