Bell's V-280 Valor is Rockin and Rollin

The tail propulsor is clutchable, not just variable pitch or "feathered". A tilt-rotor has higher comparable losses due to downwash on the wing/fuselage along with much higher disc loading, with all associated problems. The three engines on a King Stallion aren't providing variable power to another shaft, just set rate to the tail-rotor and variable to one main -rotorhead. Same with the relatively simple cross-shafting on a V-22 which doesn't provide different power or RPM to port and starboard engine when engaged, and also isn't being stressed throughout the flight. I don't really know where to begin.

They will probably have scalability problems with the transmission raising height or eating cabin space and material science/quality -control on the rigid rotor, but they seem to think it is manageable.

a reply to: RadioRobert

I can see the variable power thing being an issue, though I'd argue the duty cycle on the V-22's cross shaft is probably harder (with the caveat being that at least in any scenario where it actually performs as-designed, they'll consider themselves lucky if they even have a salvageable aircraft to rebuild the transmissions on when all is said and done).

The clutch just seems to me like another complication/possible failure point when a prop that feathers completely would accomplish the same thing, unless they're really *that* desperate to save a percentage point or two of powertrain efficiency. Like I said though, it seems like Sikorsky designed a hot rod that will struggle to carry passengers/cargo, while Bell built a flying truck that will struggle mightily as a more nimble/survivable attack platform.

At least we've moved from, "it's easy and a knock off. I don't like it" to "it sounds more complicated, difficult, and novel. I don't like it".

a reply to: RadioRobert

I'm mostly angry with Sikorsky for shattering the Westland Lynx's speed records with a goddamned compound helicopter and then having the nerve to go bragging about it.

Oh, and fwiw I think the idea of building a tough, survivable attack helicopter out of a tiltrotor is an alternatingly silly and terrifying fantasy that probably needs to stay on the screen during Avatar movies where it actually belongs.

Cruise flight. Check.

www.flightglobal.com...

theaviationist.com...

Next week, a team from Textron Inc. and Bell Helicopter will demonstrate the maneuverability of its experimental V-280 Valor helicopter, a platform that may one day replace the U.S. military's UH-60 Black Hawk fleet.

The June 18 demonstration comes six months after the V-280's first test flight as a technology demonstrator in the Army's Future Vertical Lift program.

"It's not just a flight test, it's actually a demonstration of what we have been able to achieve so far," retired Army Maj. Gen. Jeff Schloesser, executive vice president for strategic pursuits at Bell, told Military.com.

"What you will see is the aircraft go through a variety of maneuvers. ... One of the things we want to demonstrate is just how able you are to quickly reposition the aircraft in flight," he said. "When you are on the objective area, you are not flying fast, but what you do have to do is do tail maneuvers, turn maneuvers, roll and pitch maneuvers in a very accelerated way."

www.military.com...

a reply to: anzha



theaviationist.com... rotor-aircraft/

I'm mostly angry with Sikorsky for shattering the Westland Lynx's speed records with a goddamned compound helicopter and then having the nerve to go bragging about it.

Still yet to see a V22 or V280 barrel roll or loop

a reply to: Blackfinger

I've seen one roll. Not seen aloop, but it's got the power for it.

That plus the rotor head design off memory.Only a few helo types can loop.

a reply to: Blackfinger

Oh, the Lynx is definitely the rotor head. There's a few out there. Red Bull has a pretty fun demo team.


I meant I've seen a V-22 roll. Haha

a reply to: Blackfinger

The helo needs to have a rigid rotor system.

Noice Looks so much less bulky and unweildy than the Osprey.

Bell’s V-280 demonstration programme plans to continue to expand the tiltrotor’s flight envelope, with additional focus on manoeuvrability, after reaching 250kt this September.

So far, the aircraft has been tested on 50˚ banked turns at 200kt, which is the equivalent of 1.8g, says Vince Tobin, Bell executive vice-president for military business. During upcoming tests the manufacturer expects the aircraft to fly turns that generate more than 3g, he says.

www.flightglobal.com...

originally posted by: Barnalby
a reply to: RadioRobert

I can see the variable power thing being an issue, though I'd argue the duty cycle on the V-22's cross shaft is probably harder (with the caveat being that at least in any scenario where it actually performs as-designed, they'll consider themselves lucky if they even have a salvageable aircraft to rebuild the transmissions on when all is said and done).

The clutch just seems to me like another complication/possible failure point when a prop that feathers completely would accomplish the same thing, unless they're really *that* desperate to save a percentage point or two of powertrain efficiency. Like I said though, it seems like Sikorsky designed a hot rod that will struggle to carry passengers/cargo, while Bell built a flying truck that will struggle mightily as a more nimble/survivable attack platform.

I don't see how a featherd prop that is still connected to the transmission would save power the same as if you had a clutch and released the prop from the transmission. Even in beta the prop would have a fair amount of drag if still connected.

A snippet from the AvWeek article on this:

Army pilots are scheduled to fly in the V-280 again over the next few days, Josselyn said during a media tour of the Arlington test center on Dec. 11. An Army test pilot and a U.S. government senior test pilot are due to fly the tiltrotor.

They had a Blackhawk pilot fly it back in Feb as well.

aviationweek.com...

A lot of testing with models to get this far.

www.janes.com...

Plot twist: Navy isn't waiting for the Army.

322mph