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JMR (Joint Multi-Role) & FVL (Future Vertical Lift) Programs

TomcatViP

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The height of the rotor assembly does make an impression.

View attachment 627524
I see their architecture as being wrong. To me they somewhat lacked imagination.

When Sikorsky built the S-58 they showed they had the ability to reshuffle the (then new, that's right) norm when needed.

Here IMOHO the same company failed to come with a solution that wouldn't geopardize the function (the missions).

I believe that burying the GB downto floor level and side deporting the passenger cabin in two units with passageway behind and in front (where pilots would seat as in a normal design) could have led to a more practical airframe for the military. Maintenance? Unplug the side cabin (modules/clam shell ) and here you have the entire engine and gearbox at hand reach.
 
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VTOLicious

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The height of the rotor assembly does make an impression.

View attachment 627524
I see their architecture as being wrong. To me they somewhat lacked imagination.

When Sikorsky built the S-58 they showed they had the ability to reshuffle the (then new, that's right) norm when needed.

Here IMOHO the same company has failed to come with a solution that wouldn't geopardize the function (the missions).

I believe that burying the GB downto floor level and side deporting the passenger cabin in two units with passageway behind and in front (where pilots would seat as in a normal design) could have led to a more practical airframe for the military. Maintenance? Unplug the side cabin (modules/clam shell ) and here you have the entire engine and gearbox at hand reach.
We already had a discussion on that matter in the dedicated SB>1 thread: https://www.secretprojects.co.uk/threads/boeing-sikorsky-sb-1-defiant-model-s-100.24769/post-251149 ...and... https://www.secretprojects.co.uk/threads/boeing-sikorsky-sb-1-defiant-model-s-100.24769/post-295924
 

coanda

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sferrin

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I'm surprised they're still using swashplates instead of computer controlled actuators.
 

yasotay

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Risk = $$, at least in the mind of the people who decide what to spend money on in the DoD.
 

VTOLicious

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We will find out soon.

"...With its strategy, Boeing appears to be repeating the approach adopted so effectively in earlier contests to supply the US Navy with an unmanned tanker and the US Air Force with a replacement fleet of advanced jet trainers. In both those instances, it surprised its adversaries by unveiling not a full-scale mock-up but what was essentially a flight-ready prototype..."

https://www.flightglobal.com/flight...ch-could-yield-armed-scout-win/136869.article
 

F-14D

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We will find out soon.

"...With its strategy, Boeing appears to be repeating the approach adopted so effectively in earlier contests to supply the US Navy with an unmanned tanker and the US Air Force with a replacement fleet of advanced jet trainers. In both those instances, it surprised its adversaries by unveiling not a full-scale mock-up but what was essentially a flight-ready prototype..."

Another thing that may be going on is the strategy Boeing followed that helped them win T-X (and possibly KC-X). They saw that although there would be extra credit for performance exceeding the requirements, the credit actually given would not be very much given the size of the program. So instead of going for an aircraft that significantly exceeded requirements, they went for lower cost/ low risk. It worked.

We could be seeing a similar strategy here. What little bit we've seen looks like they're proportion an advanced but conventional helicopter. This could be a conventional helicopter that meets the specs but doesn't go that much beyond, unlike what Sikorsky, Karem and AVX are proposing. The bet is that there won't be enough credit given for the higher capability to balance out the higher cost and risk. This seems to be the same strategy Bell is following with Invictus. The wrinkle here, though is that Boeing has never put into production a helicopter/VTOL they've designed solely on their own. In fact, IIRC, they've only put five airframes of their own design into the air in their history: the Model 360 demonstrator, which could be argued is based on the CH-46/47, three Model 237s (YHU-61) and one Model 179 (civilian version of the 237). This could make their use of this strategy perceived as a bit more risky than Bell's.
 

yasotay

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I agree that Boeing is likely to have a relatively conservative approach. Bell has also taken this route with all of their recent government efforts. Of note both of these vendors are painfully aware of the agony of bringing new technology into government service.
 

fredymac

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Are any DIRCMs installed on attack helicopters or is there no room/electrical power for them?
 

yasotay

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The SWaP (Size, Weight, and Power) on attack helicopters is usually at a premium, which is why I suspect that DIRCM systems are not widespread. Given the expectations of the future aircraft I would be surprised to find that there is not a requirement for something beyond flares. That said, flares are much more exciting to show in business development videos, along with shooting 8Km missiles at 3Km.
 

VTOLicious

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Moose

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Is that a Pusher and a anti-torque tailrotor?
 

donnage99

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The SWaP (Size, Weight, and Power) on attack helicopters is usually at a premium, which is why I suspect that DIRCM systems are not widespread. Given the expectations of the future aircraft I would be surprised to find that there is not a requirement for something beyond flares. That said, flares are much more exciting to show in business development videos, along with shooting 8Km missiles at 3Km.
They should have added a scene of pilot squinting his eyes to target with his eyeballs.
 

fredymac

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Adjusted background to bring out more details. Seems like the "wing" is just a weapons pylon. I'm guessing they are going for the low $ bid.

Boeing FARA.jpg
 

Moose

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Adjusted background to bring out more details. Seems like the "wing" is just a weapons pylon. I'm guessing they are going for the low $ bid.

View attachment 627845
I expect underbidding Bell's gonna be tough with any flavor of compound, perhaps they're trying to shoot the gap between Bell and Sikorsky.
 

Hood

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Or maybe Boeing hopes the US Army will get scared off by the high-tech options and just keep buying warmed up Apaches forever?

I can't understand Boeing's layout, it seems dated in concept and must be as acoustically and radar reflectively bad as possible.
 

VTOLicious

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Or maybe Boeing hopes the US Army will get scared off by the high-tech options and just keep buying warmed up Apaches forever?

I can't understand Boeing's layout, it seems dated in concept and must be as acoustically and radar reflectively bad as possible.
It puzzles me as well. In particular I don't understand why they added another gearbox ( compared to the Cheyenne / Apachenne layout)
...And how can it offload the main rotor without wings?
 
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Desertfox

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Looks like the Cheyenne and the Comanche had a baby together.

It is unloading the rotor by removing its propulsion requirement, rotor is now in charge of only providing lift. That said I am surprised at the lack of wings on both the Boeing and Sikorsky entries since they would seem to be the ones that could gain the most from them.
 

yasotay

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Boeing I suspect is rationalizing that this configuration will be less risk/cost/weight than say a coaxial compound, but more responsive to Army requirements than a conventional helicopter.
 

TomcatViP

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Wings cost rotor efficiency by masking the rotor downwash. You'd be surprised how much loss is generated that way. Suffice to say that the CH47 was more efficient without than with the set of experimented wings.

 

yasotay

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@ Grey Havoc - doing anything with the Army is a gamble (especially rotorcraft).

@ TomcatViP - so even if the wing is assuming 100% (hypothetically) of the lift, it is creating more drag from the rotor wake than not having the wing?
 

Desertfox

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For slow speed and hovering flight, yes wings are detrimental, but they become more and more beneficial at the speeds the Army is asking for. The confusing thing is that the design (Bell) most affected by it has wings while the two designs that could benefit, do not.
 

_Del_

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I thought the story on the BV-347 was that the weight of the variable incidence wing cut most of the operational benefit while significantly adding to cost? In hover the wings tilted to cut DeltaP losses, but it was basically offset by the weight gain. The "cruise" portion of flight benefited, but not enough to justify cutting into the payload capability and footing the costs.
Such was my understanding, and I'm interested to hear what Tomcat (who undoubtedly knows more than me) can add.
 

_Del_

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Found these:


I'll try to pick through them later this evening if I get a chance. The abstracts don't sound damning.
 

AeroFranz

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Everything has pros and cons. However, to be efficient in cruise a compound helicopter needs a wing. Not only that, in reality it is a little bit more complicated. See attached
Nice read. Bob Ormiston (as well as sadly departed figures like Ray Prouty) is a national treasure.
 

F-14D

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For slow speed and hovering flight, yes wings are detrimental, but they become more and more beneficial at the speeds the Army is asking for. The confusing thing is that the design (Bell) most affected by it has wings while the two designs that could benefit, do not.
Karem seems to be addressing this by having a wing that is horizontal for higher speeds, but tilts to the vertical for low speed/hover.
 

H_K

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Still not completely sure why Airbus Helicopters aren’t in this race, particularly for FLRAA.

With only 2 competing technologies, one which is known to be expensive (tilt-rotor... V-280 Valor) and one which has yet to scale reliably after 10+ years of development (Advanced Blade Concept... SB-1 Defiant), you’d think there would be an opening for a lower risk, lower cost solution.

I particularly liked Airbus’ hybrid H3 concept - one platform which could built in both “fast” and “slow” versions to reduce costs via commonality and provide flexibility for different users.
https://academieairespace.com/wp-content/uploads/2018/05/HGV.pdf





Seems like they may be testing some of this commonality with RACER, which looks superficially similar to the H160... but that hasn’t been confirmed.
 
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sferrin

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For slow speed and hovering flight, yes wings are detrimental, but they become more and more beneficial at the speeds the Army is asking for. The confusing thing is that the design (Bell) most affected by it has wings while the two designs that could benefit, do not.
Karem seems to be addressing this by having a wing that is horizontal for higher speeds, but tilts to the vertical for low speed/hover.
The Chinook's did too.

BV347_wing_rotated.jpg
 

yasotay

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Still not completely sure why Airbus Helicopters aren’t in this race, particularly for FLRAA.
I suspect that part of the reason that there are not any foreign rotorcraft is that there are international trade, science and technology, and security issues.
 
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