The U.S. Army’s Future Long Range Assault Aircraft (FLRAA) programme is moving forward with two competitive demonstration contracts being awarded to Bell team and to the Sikorsky-Boeing team.

Bell is competing with its V-280 Valor solution while Sikorsky-Boeing is offering its SB>1 Defiant.

The Bell V-280 Valor

Bell V-280 Valor high speed cruise demo, 2019 Alliance Air Show.jpg

The V-280 is reported to be designed for a cruising speed of 280 knots (hence the name V-280), a top speed of 300 knots, a range of 2,100 nautical miles and an effective combat range of 500 to 800 nmi. Expected maximum takeoff weight is around 30,000 pounds.

Read more here.

The Sikorsky–Boeing SB-1 Defiant 

Image result for SB>1 Defiant

The design will have a cruise speed of 250 knots, but less range due to using the “old” T55 engine. A new engine, the Future Affordable Turbine Engine (FATE), is to meet the range requirement of 229 nmi. Compared to conventional helicopters, the counter-rotating coaxial main rotors and pusher propeller offer a 100-knot speed increase, a 60% combat radius extension, and 50% better performance in high-hot hover performance.

Read more here.

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Ian M
Ian M
6 months ago

Two very different approaches to solving the problem!

DaveyB
DaveyB
6 months ago
Reply to  Ian M

Yes, one using brute force to push it up to 250kts, i.e. the Defiant. The other a design with certain flaws for an unwary pilot. Airbus already have the answer to pusher a helicopter past 250kts. If Leonardo (Westlands) put their mind to it, they also have a legacy design that could reach 300kts.

George Royce
George Royce
6 months ago
Reply to  DaveyB

What exactly do Airbus have?

DaveyB
DaveyB
6 months ago
Reply to  George Royce

Airbus have the X3 prototype, which currently holds a number of speed records. The problem with all rotorcraft and aircraft using propellers for thrust is rotor/propeller tip speed. As the rotor rpm is generally now set and the blades pitch angle adjusted to vary the thrust. The actual speed of the aircraft through the air becomes the problem. As the aircraft’s speed increases so so does the local speed at the blade tips. The blade tips will already be operating in the transonic zone, if the aircraft goes faster it can push them into the supersonic zone. Nearly all rotor/propeller… Read more »

George Royce
George Royce
6 months ago
Reply to  DaveyB

Very interesting. What do you think about, one day having jet engine aircraft that work and act like helicopters? Would that be feasible or just too demanding on fuel?

Watcherzero
Watcherzero
6 months ago
Reply to  DaveyB

Problem with the Rotodyne however was firstly the massive noise, 106 dB, not good for something operating for a significant portion of time at low level in urban environments. And secondly the appalling fuel economy. It couldn’t use standard aviation fuel as the fuel was also used to power the rocket motors, so it had to be an enriched variety. Other thing to note was the Rotodyne actually got the majority of its lift (60%) from the wings rather than main rotor so it was more of a hovering plane than a winged helicopter. For the Airbus RACER the production… Read more »

Rudeboy
Rudeboy
5 months ago
Reply to  Watcherzero

At the time it was cancelled the Fairey engineers believed they had a solution to the noise issue that would have significantly reduced the noise down to c95db, which would have been fine.
Always thought that if they’d held on with the Rotodyne they would have got some orders from the USAF for CSAR over Vietnam in the next 5 years…would have been ideal.

DaveyB
DaveyB
5 months ago
Reply to  Watcherzero

You’re not quite correct on the Rotodyne. When in forward flight, the main-wing doesn’t start to come into affect until after 50kts forward airspeed and incrementally develops it maximal lift around 90kts forward airspeed. The maximal lift of the wing is only 50% of the aircraft’s total lift, as the main rotor in autogyro mode (no power to turn head) still develops lift, but with a reduced pitch angle and a slower rotor rpm. The main rotor in helicopter mode produced a similar amount of vertical thrust/lift as a C model Chinook, i.e. it could dead lift just over 9… Read more »

Pigeon
Pigeon
6 months ago

Are we really going to see such massive and complex airframes replace the Blackhawk and Huey?

They look far too dominated by “the need for speed” and in danger of losing attributes (ability to take fire, hard land, easily fit defensive weapons, easily maintainable) that are what has made the current generation so distinguished.

Very much seems the aviation equivalent to FCS…

Bob
Bob
6 months ago
Reply to  Pigeon

This is driven by a wargame run in 2017 where they were modelling the 82AB Div against a peer enemy. In the scenario, the enemy had commercial drone technology, long ranged GBAD and massed heavy artillery (tactics taken from Donbas campaign in E Ukraine). In the first run of the scenario, the 82nd didn’t make the landing zone. It was re-set to reduce the GBAD effectiveness – they never made it off the LZ. The main lesson identified was the critical vulnerability of heli-born manoeuvre on the modern battlefield. Created a bit of a sit up moment in the British… Read more »

DaveyB
DaveyB
6 months ago
Reply to  Pigeon

There is a need for speed! But also an increase in unsupported ferry range whilst loaded with supplies or pax. Both aircraft were required to do 250kts, with a cruising speed above 200kts. But also a self ferry range of 500nm without additional fuel tanks. The Defiant has yet to reach the top speed, if it can at all, whilst the Valor has gone past 265kts. A normal helicopter cannot achieve this. The design is inherently flawed as you are using the rotor disc as you main means of lift and thrust. The Valor and Defiant have tried to split… Read more »

john melling
6 months ago

How about the AgustaWestland AW609 ;P

Spyinthesky
Spyinthesky
6 months ago
Reply to  john melling

That’s a Bell design isn’t it. That suggests to me that Bell saw something in the Valor that they didn’t in the AW609 at least for military use, not sure what overlap there might be if any. Didn’t they originally during early development split the 609 responsibility between military and commercial sectors?

DaveyB
DaveyB
6 months ago
Reply to  Spyinthesky

Yes, both manufacturers signed a deal, where all military tilt rotor use would be produced by Bell, whilst Leonardo would do civilian. Part of the deal, precludes arming the 609. The UAE was supposed to be the launch customer with a number of coastguard versions, but nothing has happened for a while.