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Bell V-280 Valor

RavenOne

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Sorry havent been around on here was at Heli Expo 2013 in las Vegas a month ago and catching up on leads. Anyhow I went on my FB and Literally a few minutes ago, Bell unveiled their newest product not yet built - a new generation light utility battlefield tiltrotor - The V280 Valor at Quad A Convention

http://bellv280.com/

http://www.youtube.com/watch?v=1O3Onyas984&feature=youtu.be

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Grey Havoc

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Somewhat unexpected. Thanks for the heads up!
 

Triton

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A notable feature of Bell's concept for the FVL Medium utility variant to replace the Black Hawk - the engines do not tilt with the proprotors, as they do on the V-22. This is to allow ingress and egress to the side-opening doors (the V-22 has a rear ramp) and clear fields of fire for the door gunners. And, in addition to the V tail, the wing has no forward sweep.
Source:
http://www.aviationweek.com/Blogs.aspx?plckBlogId=Blog:27ec4a53-dcc8-42d0-bd3a-01329aef79a7&plckPostId=Blog%3A27ec4a53-dcc8-42d0-bd3a-01329aef79a7Post%3A085f3884-fb49-4997-a479-7cd3a38af7d7
 

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Stargazer2006

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Nice surprise. Thanks a lot for sharing, RavenOne and Triton!
 

Triton

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"Bell Helicopter Introduces the Bell V-280 Valor Tiltrotor at AAAA"
Posted on April 10, 2013 · Posted in Bell FVL V-280

Source:
http://bellv280.com/bell-helicopter-introduces-the-bell-v-280-valor-tiltrotor-at-aaaa/

FOR IMMEDIATE RELEASE

FORT WORTH, TX (April 10, 2013) – Bell Helicopter, a Textron Inc. company (NYSE: TXT), revealed today the Bell V-280 ValorTM, its offering for the Joint Multi Role/Future Vertical Lift (FVL) Technology Demonstrator (JMR/TD), at the 2013 Army Aviation Association of America’s (AAAA) Annual Professional Forum and Exposition in Fort Worth.

“The introduction of the Bell V-280 Valor underscores our commitment to our military customers. The Bell V-280’s unmatched capabilities in speed, range and payload, and its operational agility combine to deliver the best value for the U.S Army,” said John Garrison, president and CEO at Bell Helicopter. “This aircraft is the most advanced and operationally effective vertical lift solution, providing the Warfighter a decisive advantage. The name itself makes an important statement of its own: V representing vertical lift, 280 representing its unmatched speed, and Valor as a tribute to the service men and women who approach their jobs with valor every day.”

The Bell V-280 Valor, Bell Helicopter’s third generation tiltrotor, offers the U.S. Army the highest levels of maturity and technical readiness. With its U.S. Army-centric design, the Bell V-280 has the capacity to perform a multitude of missions with unparalleled speed and agility. The Bell V-280’s clean sheet design reduces complexity compared to previous generation tiltrotors, with fewer parts, as well as non-rotating, fixed engines. The Valor delivers the best value in procurement, operations and support, and force structure, providing increased maintainability, component reliability and systems designed to reduce operational and support costs.

“The Bell V-280 is a combat multiplier with a cruise speed of 280 knots and combat range of up to 800 nautical miles. Tiltrotor is the only vertical lift platform that can rapidly self-deploy to any theater,” said Mitch Snyder, executive vice-president for military programs at Bell Helicopter. “And our technology demonstrator is a true medium class aircraft accommodating a crew of four and 11 troops, which translates to the highest level of certainty for a future program of record.”

The Bell V-280 Valor’s Army-centric design boasts a number of unmatched capabilities and transformational features including:
  • Speed: 280 KTAS cruise speed
  • Combat range: 500-800nm
  • Strategically Self-Deployable – 2100nm Range
  • Achieves 6k/95
  • Non-rotating, fixed engines
  • Triple redundant fly-by-wire flight control system
  • Conventional, retractable landing gear
  • Two 6’ wide large side doors for ease of ingress/egress
  • Suitable down wash
  • Significantly smaller logistical footprint compared to other aircraft

“Bell Helicopter is leading the development of next-generation tiltrotor technology, because it’s the best technology for future vertical lift. The U.S. Army’s JMR/TD Operational Effectiveness Analysis Report stated that advantages in speed and fuel efficiency made the tiltrotor the most operationally effective concept aircraft,” said Snyder. “Based on a strong foundation of 55 years of tiltrotor experience, including combat-proven platforms, Bell Helicopter has created the ultimate solution for the Army’s FVL needs.”

Bell Helicopter is the world’s premier tiltrotor expert ranging from first generation XV-3 and XV-15, to the second generation 609 civil tiltrotor and the combat-proven V-22 Osprey. Backed by unmatched experience, Bell Helicopter is building a team of premier aerospace leaders, the best engineering resources and industrial capabilities in the industry to meet the U.S. Army’s needs.
 

Triton

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Model of Bell V-280 Valor on display at Army Aviation Association of America Annual Professional Forum and Exposition 2013 in Fort Worth.

Source:
http://www.shephardmedia.com/news/rotorhub/quad-2013-bell-unveils-next-generation-tiltrotor/
 

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yasotay

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Well other than the dynamics it seems the two front runners seem to have come to a similar conclusion.
 

Abraham Gubler

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Or Bell has no choice but to offer a tilt rotor for JMR because all their helicopter experts left and formed AVX.
 

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Jemiba

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Triton said:
A notable feature of Bell's concept for the FVL Medium utility variant to replace the Black Hawk - the engines do not tilt with the proprotors, as they do on the V-22. This is to allow ingress and egress to the side-opening doors (the V-22 has a rear ramp) and clear fields of fire for the door gunners. And, in addition to the V tail, the wing has no forward sweep.
This principle was chosen for EUROFAR, too : http://www.secretprojects.co.uk/forum/index.php/topic,857.0.html
 

Triton

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Abraham Gubler said:
Or Bell has no choice but to offer a tilt rotor for JMR because all their helicopter experts left and formed AVX.
Do any of us believe that Bell would have offered a high-speed compound helicopter with coaxial rotors and pusher props for JMR/FVL?
 

Abraham Gubler

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Triton said:
Do any of use believe that Bell would have offered a high-speed compound helicopter with coaxial rotors and pusher props for JMR/FVL?
If Troy Gaffey was still Bell's Chief Engineer and Senior VP of Research and Engineering then maybe they would have. Who else? Maybe Bell's CFO, Directors of Systems Integration and Structures Engineering, Chief of Drive System Design, and maybe 16 other senior engineers. designers and managers. All of which who if were still in Bell would be doing what they are now doing for AVX Aircraft.
 

Pioneer

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Hey nice effort RavenOne on the V280 Valor topic!It would be nice to think that much of the complexity of the MV-22 Osprey could be ironed out - or even better eliminated! I hope this would go a long way in reducing the exorbitant price and reliability of the MV-22!Is it just me or does the artwork of the fist couple of pics you posted have an UH-60 Blackhawk fuselage look about it?For the sake of the hard-pressed U.S. military (Budget reductions and an awful high rate of program stuff-ups), wouldn't it make sense to utilise the true and trusted and combat proven fuselage as the basis of this new V280 Valor? But then the U.S. military complex would not favour such co-operation, when they so much want competitiveness ::) I hope for the U.S. military, if this program matures and is deemed what it wants and needs. It will be able to run this program sensibly, cost effective, and on time. P.S. is the armed (gunship/close air support?) variant on that Youtube video a dedicated variant? or does the assault transport variant also have retractable weapons capability? For this could be the new LHX in a sense of utilising as much commonality into two various role. A scheme which I think has great merit!! RegardsPioneer
 

Stargazer2006

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Looking back on the complicated development history of the operational Bell VTOL, it is good to see that the complicated solution of tilting two enormous engines+props has been discarded. Only regret is that the Bell team opted for a solution which was already there in the venerable XV-3 ancestor back in 1954: tilting the props without tilting the engines. It shocks me that it took nearly six decades to go back to it. Ducted fans, tilt-rotors, folding rotors... They've gone full circle and went for the solution that was safest, proven on full-scale prototype and probably less costly too.
 

Jemiba

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Stargazer2006 said:
Looking back on the complicated development history of the operational Bell VTOL, it is good to see that the complicated solution of tilting two enormous engines+props has been discarded.
I'm not quite sure, that tilting the rotors only, with the need to bend the cyclic and collective controls
really eases the problems. To my opinion, it may result in a slight decrease in weight, but to an increase
of complexity.
 

yasotay

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Bell made a point of "cost" being a major design driver. As to just taking a H-60 and slapping a new set of dynamics on it; that is no simple engineering feat. Especially when you consider that the new requirement called for an aircraft that cruises above the Vne of the H-60. Still there is a reason that both the Boeing/Sikorsky and Bell have aircraft that look very much like H-60 with new dynamic (rotors & power train) components. The requirements they were asked to design to are similar to the UTTAS except for cruising at 230 knots and going much further.

Pioneer – yes the attack variant does appear to be very similar. That too is a matter of cost as a major design priority. Commonality is one area that is being looked at by all of the competitors, how much becomes the question. Do you have a “jack of all trades” aircraft, a common set of dynamics on different fuselage (a.k.a. the H-1Y/Z) or purpose built mission aircraft? There are grand arguments to be made for any of the philosophies mentioned above.

I have watched the “hooah” promotional several times now and Bell crammed as much into that as they could for the discerning viewer. Starting with the discussion with the first sergeant being told hot/high is just another mission, without FARP (mobile refuel station), where if you watch in the background a couple of V-280 are sling loading a couple of M777 howitzers (UH-60 can’t do that), to the change of missions for first platoon a hundred miles away on the same mission and without having to go to the FARP. They also made a point of letting you see how many troops were getting on the aircraft to go to that hot and high mission. A number of troops that the current assault helicopter cannot do. There is even the point made that the tilt rotor is zooming along until they are only one kilometer from the landing zone. This is a survivability honorable mention for the discerning viewer who knows that the most difficult part of the combat assault mission is the landing zone. The less time you are doing the low slow thing, the less time the opposition has to shoot at you. The infantry being able to maintain contact with the use of a tablet and talk with the crew and other aircraft is a nice note. In fact the whole promo is as much for the infantry as it is for the aviator.

As to program being sensible, cost effective, and on time… Well that has not been a hallmark of western military aerospace for the majority of programs for many years. Between the company and corporate financial disconnects and government bureaucrats with competing and often opposing requirements it is a wonder anything is ever done. I remember the utter shock at how phenomenally expensive the Blackhawk was to the beloved Huey it was to replace. That program was rather well run but still took over a decade to go from requirement determination to prototype competition. With all of the extra visibility and pervasiveness of information, I don’t hold out much hope. I am reminded of the old zinger – An elephant is a horse designed by committee.

Still as an old assault pilot I give Bell good marks for coming out of the gate. In fairness I would say the same for the Boeing/Sikorsky effort as well. Will be interesting to see who else comes to the game.
 

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Bizarre that they have stuck with the S-70's 11-man squad size*. Suits the US Army but too small for the USMC ( 17-man squad ), UK ( 13-man ) or Israelis ( 12-man squad ) plus the need for the command group to ride along. Though I suppose they could trade-off one of the four crew for a couple of extra riflemen.

The S-70 has been adopted by forces modelled on the US Army TOE but for others the Mi-17 or Puma variants are more capcious and mean that a squad doesn't have to be split over two or more helicopters.

* though in practice with the amount of personal kit being hauled around in current operations it is a squeeze even to fit 11 men into an S-70 and with kit on their laps, under the seat and at their feet there isn't much freedom to move.
 

TomS

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Not much point in going after the USMC market with this since a) it doesn't fold and b) the Marines already have V-22. And the overseas market is relatively small compared to the US that it's not really worth focusing too hard on that either.

I'm curious how air transportable this will be. It looks like the wing has to come off to fit in a C-17 or C-5, which sounds like a lot of work to reinstall, since it means the engines are coming off the airframe. They're clearly emphasizing self-ferry range, but going trans-Pacific in a bird like this seems like a horrible ride.
 

sferrin

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My money is on Sikorsky. The words "tilt-rotor" have stink all over them (justified or not). If they get their S-97 demonstrators rolled out soon enough that will only help them.
 

Kiltonge

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TomS said:
And the overseas market is relatively small compared to the US that it's not really worth focusing too hard on that either.
What's the S-70 at now, 2,100 units? Compared to 900 Super Pumas alone. That's a lot of market to casually discard.

What I was trying to express was that if they sized it for a reasonable squad composition then the overseas market wouldn't be 'relatively small'.

The 204 / 205 sold well because it was a pioneer in army mobility. Many armies adopted it even though it didn't match their TOE, simply because it was available and fairly priced.

But when they moved on to the second-generation of squad transport the S-70 lost-out specifically because it was too cramped. It is bigger than as big as a Sea King but carries 11 troops. Even the Bell 214 sold better on the export market.

But it's Bell's call. If the DoD doesn't buy it, they haven't a hope of finding anyone else that will want such a tailor-made type.

Edit: Sikorsky developed the S-92 as a reaction to the success of the Super Puma and the prospect of the NH-90. That's what the S-70 could have been had it not been for the ridiculous US Army requirement to fit it in a C-130.
 

Stargazer2006

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Kiltonge said:
Even the Bell 214 sold better on the export market.
Uh? Do you have figures to back this up?
 

Triton

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sferrin said:
My money is on Sikorsky. The words "tilt-rotor" have stink all over them (justified or not). If they get their S-97 demonstrators rolled out soon enough that will only help them.
One of the reasons why Bell dissolved its joint venture with Agusta to market and develop the BA-609? Is there a current civilian market for tilt rotor aircraft? Or does Bell now consider tilt rotor to be a product only for military customers?
 

sferrin

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Triton said:
sferrin said:
My money is on Sikorsky. The words "tilt-rotor" have stink all over them (justified or not). If they get their S-97 demonstrators rolled out soon enough that will only help them.
One of the reasons why Bell dissolved its joint venture with Agusta to market and develop the BA-609? Is there a current civilian market for tilt rotor aircraft? Or does Bell now consider tilt rotor to be a product only for military customers?
No idea. I haven't followed the 609 that closely. This is the first I heard they bought Bell out of the project.
 

Triton

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Photographs from the Bell Helicopter booth at AAAA 2013.

Source:

http://www.facebook.com/media/set/?set=a.611467655547881.1073741831.137576202937031&type=1
 

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sublight is back

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Looking at the wing xray, there is no central gearbox like the Osprey. Are they going to have a parachute backup when one engine fails? I don't imagine it will be able to pull off an auto-rotate.
 

TomS

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That picture only shows the structural elements. There could be provision for a cross-shaft and gearbox behind that transverse spar and you wouldn't be able to see it from this angle
 

yasotay

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First Triton, thanks for the great information and pictures.

If you look at the second slide of the presentation three of the six bullets are about cost. One of the points in the first bullet is about cost. I imagine that they are going after the Army mainly since the Army is the only one who has put any money into the endeavor. If the Naval services decide they want it then it will most likely gain ~1000 lbs turning into a transformer, like the current TR. I imagine if the customer base decides that they want more room, then they will scale the aircraft up to meet the need. Everything about this aircraft (and the Boeing/Sikorsky) is about keeping cost down. That is why the attack version is basically the same airframe. Keeps production cost down. I suspect even the decision to go with doors instead of a ramp was to keep cost down, as ramps make for more complex airframes and add weight. Weight = $.

It will be very telling if Bell can keep the O&S cost competitive with less complex dynamics. Because fuel is becoming a very big cost driver and helicopters are notorious gas pigs. The more like a fixed wing you can make the machine the more fuel efficient it is. One area I think the TR has going for it.

Self deploy at ~230 knots. Army Aviation does it all the time with its fixed wing aircraft (C-12 variants). The Aviation Center Commander briefed in January at AUSA that self deploy capability is huge to four star commanders as it frees up precious airlift and sea lift assets to move other things. They showed a Pacific route with the longest leg being about 1800 NM. Had aircraft getting to the Philippines in as little as three days. Still I imagine if you had to fly one of the V-250 in strat-air due to maintenance issues you would have to take the wing/rotor/engine assembly off like any other fixed wing aircraft. I have to wonder if the Boeing/Sikorsky design (as tall as it is) fits in a C-17 as is or do you have to take the rotor head off. How about under deck on a Navy ship?

Well maybe there will be a competitive fly off since the Department of Defense has said they want to do that sort of thing. Will be fun to watch this process.

Right up to the point that the funding is taken in support of the sixth generation fighter program we are so desperately in need of. :mad:
 

Abraham Gubler

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sublight is back said:
Looking at the wing xray, there is no central gearbox like the Osprey. Are they going to have a parachute backup when one engine fails? I don't imagine it will be able to pull off an auto-rotate.
The V-22 has a centre gear box not because it is needed to connect the transmission crossdrive but because it has an APU and other ancillaries running off it. I would imagine the V-280 is an all-electric aircraft and wouldn’t need the same level of hydraulics as the V-22 nor the APU hooked up to the prop rotors. The V-280 could easily have a crossdrive in the wing but likely without the central ancillary connection. As to auto-rotating tilt rotors don’t do that. Instead they do what aircraft with wings that lose engine power do: they glide.
 

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Abraham Gubler said:
The V-22 has a centre gear box not because it is needed to connect the transmission crossdrive but because it has an APU and other ancillaries running off it. I would imagine the V-280 is an all-electric aircraft and wouldn’t need the same level of hydraulics as the V-22 nor the APU hooked up to the prop rotors. The V-280 could easily have a crossdrive in the wing but likely without the central ancillary connection. As to auto-rotating tilt rotors don’t do that. Instead they do what aircraft with wings that lose engine power do: they glide.
The V-22, like the XV-15, needs a center gearbox because the wings are swept forward. The wings were swept forward for flapping clearance in airplane mode given the location of the proprotors relative to the wing. The V280 wings have no sweep so a center gearbox wouldn't be required on the cross shafting for that reason.

The V-22 can autorotate and has the capability to flare to a survivable sink rate touchdown from a fully developed autorotation. The problem is transitioning from airplane mode windmilling to helicopter mode autorotation without losing too much rotor rpm and/or altitude. It's doable but requires altitude and a fairly high level of proficiency in the maneuver. Since the V-22 can glide farther as an airplane to reach a suitable crash landing site, a crash landing in airplane mode is survivable (the composite proprotor blades turn into broom straw), and the conversion back to helicopter is problematic, the Navy decided to have the pilots remain in airplane mode in the event of a loss of power from both engines in airplane mode.

With respect to fixed versus tilting engines, Bell selected the tilting option for the XV-15 and the V-22 from an overall weight standpoint. Mounting the engines so that the power was transmitted with spur gears rather than the less efficient bevel gears that would be required with fixed engines was part of the tradeoff. There's also some benefit for engine inlet conditions and the longitudinal location of the engines relative to the proprotor transmissions. It is a close call (Boeing opted for fixed engines on its proposal for the XV-15 program and now Bell has on the V-280) but not tilting the engines is by no means the obvious and best configuration. (The XV-3 had a single radial engine mounted in the center of the fuselage; tilting it was not a sensible option.)
 

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I'm wondering how much wider / bigger an LZ will need to for an assault landing in one of these.

Even if each rotor is smaller than that on a H-60, combined, they still look like making the helo wider.

I also think that aiming for H-60 loads, in terms of equipped troops is a bad idea. Since 2001, troops have a LOT more gear with them, so need a lot more space for weight / bulk.

Wouldn't be a problem if 15 or even 18 / 20 was a better design load.


Regards,
Gerard
 

Abraham Gubler

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Gerard said:
I also think that aiming for H-60 loads, in terms of equipped troops is a bad idea. Since 2001, troops have a LOT more gear with them, so need a lot more space for weight / bulk.

Wouldn't be a problem if 15 or even 18 / 20 was a better design load.
The Black Hawk loading takes into account the additional gear troops carry. In Australian use the Black Hawk can carry either 15 soldiers in patrol order sitting on the floor or 10 in marching order with back packs and gear. Australian Black Hawks have different, less space efficient seating arrangements to US Army ones. The simple solution to having to carry more soldiers is add another helicopter to package. No one is losing any sleep over this in the Army and if the Australian Army had a do-over they would take the slightly less number of seats in the UH-60M over the MRH 90 any day of the week.
 

yasotay

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Remember that the program is very early in the start up phase. I suspect that Bell (nor Boeing/Sikorsky for that matter) has ignored the Army's (a.k.a. the customer) desires. So I suspect the number of troops came from the Army. If the Army changes its mind and goes for say 14 troops then all of the aircraft will get bigger, which means they will cost more.

I think the Blackhawk 15 troops sitting on thier kit has become universal. Did the same in the US.
 

F-14D

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Tailspin Turtle said:
With respect to fixed versus tilting engines, Bell selected the tilting option for the XV-15 and the V-22 from an overall weight standpoint. Mounting the engines so that the power was transmitted with spur gears rather than the less efficient bevel gears that would be required with fixed engines was part of the tradeoff. There's also some benefit for engine inlet conditions and the longitudinal location of the engines relative to the proprotor transmissions. It is a close call (Boeing opted for fixed engines on its proposal for the XV-15 program and now Bell has on the V-280) but not tilting the engines is by no means the obvious and best configuration. (The XV-3 had a single radial engine mounted in the center of the fuselage; tilting it was not a sensible option.)

...FWIW, I'm still around and hope to actively participate once again in the foreseeable future. I just dropped in to pass on this Bell concept drawing of an earlier version of what eventually became the V-280.
 

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Triton

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Photos of the Bell V-280 Valor models from the AAAA convention posted by the American Helicopter Society (AHS) International on Facebook.

Source:
https://www.facebook.com/media/set/?set=a.10151516962220528.1073741829.80119815527&type=3
 

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Triton

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<iframe src="https://www.facebook.com/video/embed?video_id=4601875335299" width="1280" height="720" frameborder="0"></iframe>
 

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Tailspin Turtle said:
Abraham Gubler said:
The V-22 has a centre gear box not because it is needed to connect the transmission crossdrive but because it has an APU and other ancillaries running off it. I would imagine the V-280 is an all-electric aircraft and wouldn’t need the same level of hydraulics as the V-22 nor the APU hooked up to the prop rotors. The V-280 could easily have a crossdrive in the wing but likely without the central ancillary connection. As to auto-rotating tilt rotors don’t do that. Instead they do what aircraft with wings that lose engine power do: they glide.
The V-22, like the XV-15, needs a center gearbox because the wings are swept forward. The wings were swept forward for flapping clearance in airplane mode given the location of the proprotors relative to the wing. The V280 wings have no sweep so a center gearbox wouldn't be required on the cross shafting for that reason.

The V-22 can autorotate and has the capability to flare to a survivable sink rate touchdown from a fully developed autorotation. The problem is transitioning from airplane mode windmilling to helicopter mode autorotation without losing too much rotor rpm and/or altitude. It's doable but requires altitude and a fairly high level of proficiency in the maneuver. Since the V-22 can glide farther as an airplane to reach a suitable crash landing site, a crash landing in airplane mode is survivable (the composite proprotor blades turn into broom straw), and the conversion back to helicopter is problematic, the Navy decided to have the pilots remain in airplane mode in the event of a loss of power from both engines in airplane mode.

With respect to fixed versus tilting engines, Bell selected the tilting option for the XV-15 and the V-22 from an overall weight standpoint. Mounting the engines so that the power was transmitted with spur gears rather than the less efficient bevel gears that would be required with fixed engines was part of the tradeoff. There's also some benefit for engine inlet conditions and the longitudinal location of the engines relative to the proprotor transmissions. It is a close call (Boeing opted for fixed engines on its proposal for the XV-15 program and now Bell has on the V-280) but not tilting the engines is by no means the obvious and best configuration. (The XV-3 had a single radial engine mounted in the center of the fuselage; tilting it was not a sensible option.)

Tailspin:

One thing I note from the video is that the proprotors on the V-280 seem to pivot a lot faster than they do on the V-22 or XV-15. I wonder if that's a function of not having to tilt the entire engine assembly. So even though fixed engines may be somewhat more complex, this might be another advantage. It minimizes the time that you're in that intermediate stage where the functions of the cockpit controls get "mixed". Also, since autorotation was discussed, I wonder if another consideration was that you could glide much farther to a landing area in fixed wing mode, but once there, with a more rapid translation of the proprotors, rotating them for vertical mode on final could make for a softer autorotational touchdown.
 
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