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

aonestudio said:
The ALTIUS-700 carries 300 percent more payload than the -600 and endures up to five hours of flight, depending on payloads, which are customizable and include ISR, cUAS, electronic warfare, munitions and signals intelligence.
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Why would an aircraft with 5 hour of range need to be carried by another aircraft, one with both poor intrinsic payload/cost and fuel/range? Just add bigger fuel tanks!

yasotay said:
Mostly because they have failed to get the DoD to comprehend the necessity for such a platform. Nor that the Army does not conduct reconnaissance in the same manner as that done by other services. Nor do I think they have adequately outlined that UAV cannot land next to the supported ground commander and talk over a map about what is "over the next hill", especially when communications means for the UAV are inoperable.
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I really do wonder if they even have a good case here. It seems more useful to invest in reliable communications than to spend big bucks for a contingency where people being face to face with eyeball mkI is the best course of the action, since it probably means you've already lost.

Then there is the question of using a bespoke design for this. Is spending an entire aircraft development program to add two dozen knots and cut the rotor diameter is really going to matter if one is on the wrong end of a manpad or an air superiority fighter? Pushing platform performance helps when it operates on the technological edge of opponent countermeasure and demand escalation from opponents, while it does little if the marginal performance improvements does little.
 
@shin_getter - I suppose we will see. Given the plethora of anti-UAS technologies out there, or under development, unmanned systems may not be the panacea that everyone thinks. Given the expected challenges of cyber warfare as well, I do not think the US Army is ready to completely throw out a fall back method. Certainly having ten unmanned things for the cost of one manned things is better value for the cost. However if those ten things cannot operate because they can't figure out where they are or where they are going, nor able to communicate, well they are useless war machines. A manned platform with a map and old fashioned compass and watch can still go places. It can then be landed at the ground commanders HQ and report the observations made in person to the maneuver commander. Having trained for and done that mission in major combat operations, I will admit to having a prejudiced opinion.

All things work brilliantly in pristine conditions. Major combat operations are the antithesis of pristine conditions.
 
yasotay said:
On the AURA effort, I think that V-280 dynamic components married to a new attack/recon fuselage would be able to meet the desires of the USMC. I do not know if they would be willing to compromise on the utility variant, only being able to keep up with MV-22B. There is of course opportunity for improvement with the Rolls Royce engine. Improved engines and new prop-rotors might be more economical than a whole cloth new air vehicle. Although Karem is an outlier I would love to see get to flight, I suspect that would add years (and $$) to the program development effort. Not likely something the USMC, nor the DoD, would be overly enthused at doing.
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AURA is mostly quite a jump up fro FLRAA requirements, even before Army lowered requirements for the latter. For example, Army's requirement for max cruise speed is at maximum continuous power, while Marines' requirement for its even higher max sustained speed is at 90% max continuous power. I suspect V-280 with a variant of the existing engines could be used (I believe the AE-1107C version in Osprey is higher powered that the AE-1107F in V-280), but the proprotors at least would have to be redone.

While the fuselage may have to be modified from the straight V-280 configuration for AURA, there wold be no need for a dedicated attack fuselage. The Attack and utility variants would share the same fuselage, with troops in the Utility variant and internal weapons in the Attack version.

I'd also like to see Karem in the AURA mix. Unfortunately. I agree the USMC won't have enough money to fund three competitors, and you know LM-Sikorsky has enough political pull to get themselves included. OTOH, I'm not convinced they could build an X2 that could meet the Marines' needs.
 
yasotay said:
I suspect the need to compromise is already being worked.
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An interesting thought experiment would be: Where do you think they'd compromise?

They've already mandated that FARA must use the ITE for propulsion, and that engine is also planned for reengining UH-60s and AH-64s, so I don't think they'll back off on that (it would also be too embarrassing). Similarly, I think they'll hold firm on the armament load, a cannon and eight JAGM (it appears the Invictus may be able to carry sixteen at the price of reduced performance).

However, what else may be reduced? Range? Rotor diameter? Speed? ...
 
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An in-house perspective:
“This is a long-range assault mission — that’s what it is, it’s not a cargo-delivery aircraft.” Lemmo said. “In a drag race, their aircraft is faster, no doubt about it. In the total mission time, ours will be faster. It flies like a helicopter — it’ll get there quick and it can get into much tighter spaces, just like a Black Hawk.”
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www.ctinsider.com

‘For all the marbles’: Black Hawk replacement decision looms for Sikorsky in 2022

As Black Hawk production nears its sunset, Sikorsky is readying its Stratford plant to...
www.ctinsider.com www.ctinsider.com
 
TomcatViP said:
An in-house perspective:
“This is a long-range assault mission — that’s what it is, it’s not a cargo-delivery aircraft.” Lemmo said. “In a drag race, their aircraft is faster, no doubt about it. In the total mission time, ours will be faster. It flies like a helicopter — it’ll get there quick and it can get into much tighter spaces, just like a Black Hawk.”
Click to expand...

www.ctinsider.com

‘For all the marbles’: Black Hawk replacement decision looms for Sikorsky in 2022

As Black Hawk production nears its sunset, Sikorsky is readying its Stratford plant to...
www.ctinsider.com www.ctinsider.com
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I don't know how they can make those statements. especially that total mission time one Despite their claim to decelerate faster, that limited portion of the flight doesn't seem to be enough to overcome a nearly 50 knot speed advantage. And until we can get specific dimensions, it appears that both will fit in the footprint of a Black Hawk, so I'm not clear on the "tighter spaces".
 
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Assault landing involves coming low and fast before slowing down abruptly for a landing. This is where the reverse pitch on the pusher propeller and the classic rotor config helps.
 
@F-14D - AE-1107F a derated C? Could be right. I think there is too much DoD political within the constrained fiscal environment for a whole cloth new platform that a V-280 could likely be made to meet. Of course the USMC has become very adept at playing that game so who knows. As to the X2 being a competitor, do not think you can get that platform economically up to the high cruise speeds that the USMC is expecting.
@TomcatViP - Sikorsky has been banking on that assault landing from the beginning. However, it is a mission that the aircraft does less than 5% of the time. Most of the UH-60 "Utility" missions are moving stuff from point A to B. It will be interesting to see how, or if, the bean counters take that into consideration.
 
TomcatViP said:
Assault landing involves coming low and fast before slowing down abruptly for a landing. This is where the reverse pitch on the pusher propeller and the classic rotor config helps.
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I'm well aware that Sikorsky promises Defiant will decelerate faster in a level fuselage attitude (an important caveat sometimes overlooked) in the terminal phase. For max deceleration, the Valor is going to rely on drag (possibly including fairly flat proprotor pitch before the conversion begins) as it converts back to rotorborne flight and will lift the nose like a regular helo does in the terminal phase. Frankly, if it achieves its goals I expect Defiant will be able to HOGE at a significantly higher altitude than V-280. although the latter should meet the Army's requirement. Neither of these concepts is going to better than the other in every single thing.

What I am questioning is the statement that except for an artificially constrained scenario, the Defiant will live up to the statement,, "In the total mission time, ours will be faster", given the significant speed difference between the two for the overwhelming portion of the mission.. Regarding agility, Valor has already demonstrated that it meets or exceeds the Army's requirements.
 
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yasotay said:
@F-14D - AE-1107F a derated C? Could be right. I think there is too much DoD political within the constrained fiscal environment for a whole cloth new platform that a V-280 could likely be made to meet. Of course the USMC has become very adept at playing that game so who knows. As to the X2 being a competitor, do not think you can get that platform economically up to the high cruise speeds that the USMC is expecting.
@TomcatViP - Sikorsky has been banking on that assault landing from the beginning. However, it is a mission that the aircraft does less than 5% of the time. Most of the UH-60 "Utility" missions are moving stuff from point A to B. It will be interesting to see how, or if, the bean counters take that into consideration.
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If I remember correctly, Rolls says the F is an 1107 optimized around the Valor's needs and profile and had ~ 6,000 shp vs. the C's 7,000. Both Bell and Sikorky had to scramble when it became apparent that Army's schedule for original engine it wanted for FVL, FATE, was not going to be ready in time for FLRAA.
 
F-14D said:
TomcatViP said:
Assault landing involves coming low and fast before slowing down abruptly for a landing. This is where the reverse pitch on the pusher propeller and the classic rotor config helps.
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...

What I am questioning is the statement that except for an artificially constrained scenario, the Defiant will live up to the statement,, "In the total mission time, ours will be faster", given the significant speed difference between the two for the overwhelming portion of the difference.. Regarding agility, Valor has already demonstrated that it meets or exceeds the Army's requirements.
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A constrained scenario indeed. It is a calculation on Sikorsky's part that the Army will not consider the new implications of range and speed; the Army will rationalize the requirement against current doctrine. Sadly, not a bad calculation. However like all innovations it will be those who actually use the platform who develop the new doctrinal means.

The Army is likely battling behind closed doors between the cold warriors and "la nouvelle école" as to how to operate in the future. Not that this is new either.
 

vmscutaway-copy.gif


Vertical Motion Simulator (VMS)

This simulator has a substantial 6 degree of freedom motion envelop,but is very limited in rotation. It has ±30 feet of heave, ±20 feet of lateral translation and ±4 feet of longitudinal translation.The current gimbal system limits the roll axis to ±18 degrees, the pitch axis to ±18 degrees and the yaw axis to ±24 degrees. Figure is a drawing of the VMS and its motion systems. While this may be suitable for some applications, most high fidelity motion cues for the aerospace and aeronautical industry requires more rotational motion. The VMS was initially built to mimic the motion of rotorcrafts, which does not require unlimited rotation about any axis (Alponso et al. 2009). In order to produce accurate motion cues within the physical limitations of the VMS, washout filters are used in the motion cueing algorithms
 
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@Moose - Both men are retired Lieutenant Generals, and Army Aviators. Both were commanders of the Army Aviation Center. Both have or are working for the Sikorsky/Boeing Team. To get to that level, one learns how to be very careful with the words they use. I think their logic is that, while the speed/range of their product may not be as good as Bell, it is much better than H-60. They believe that their platform is much better on small and urban landing areas. So; much improved performance and best in class actions on the objective is their message. "Actions at the "X"", has been a term used for the FLRAA program for years. Their product is Defiant X.

They are banking on that.
 
yasotay said:
@Moose - Both men are retired Lieutenant Generals, and Army Aviators. Both were commanders of the Army Aviation Center. Both have or are working for the Sikorsky/Boeing Team. To get to that level, one learns how to be very careful with the words they use. I think their logic is that, while the speed/range of their product may not be as good as Bell, it is much better than H-60. They believe that their platform is much better on small and urban landing areas. So; much improved performance and best in class actions on the objective is their message. "Actions at the "X"", has been a term used for the FLRAA program for years. Their product is Defiant X.

They are banking on that.
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And Bell no doubt has its ex-uniformed advocates. No surprise there. Regarding landing areas, remember that Army is concerned with urban and small landing areas for FARA. That's why the FARA rotor diameter is mandated to be no more than 40', one of the reasons that serious doubts exist as to whether a FARA craft can be built that meets all the specifications..

For FLRAA, the Army has specified that a certain number of them (I'm not sure how many) must be able to operate from an area of a specified size, all rotors turning. I'm not sure if they are how specific they are on the actual footprint of one. I suspect that both craft will be somewhat larger than an H-60 when completely "unfolded".
 
FLRAA has to be able to put 8 (I think) aircraft on a football pitch simultaneously. Since the competitor is capable of that, it is not a point to be made by either vendor.
 
F-14D said:
Regarding landing areas, remember that Army is concerned with urban and small landing areas for FARA. That's why the FARA rotor diameter is mandated to be no more than 40', one of the reasons that serious doubts exist as to whether a FARA craft can be built that meets all the specifications..
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Is this 40ft requirement really that critical in real life?

It feels rather arbitrary… ultimately a helo with a certain speed/range/payload design requirement is going to weigh X tons, and this weight typically drives the optimal rotor diameter. What if the right answer is 41 or 42 or 45ft?
 
Think Somalia and Blackhawks. A great deal of air assault would take place in urban area where opposing forces will invariably settle to slow down the main assault when outflanked.

Disagregated and discreet basing will also require units to be operating from position that are difficult to identify. The smallest the footprint, the greater the operational flexibility.

Regarding having one or two feet extra will certainly not affect the final outcome. If no trick have been pulled To reach such number.
 
I believe that the diameter requirement is a SOF requirement. Regular Army aeroscouts rarely fly between the buildings, where a toaster or potted plant can make a decent MANPAD. Not to mention that a significant part of the world has masses of wires of varied diameter hanging between buildings. SOF of course lands on roofs and in back yards, so...
 
@yasotay Exactly. I don’t see a size restriction for conventional armed reconnaissance. And the Blackhawk Down-style SOF mission is odd since FARA can’t carry passengers… so why would it be landing or flying in tight spaces?
 
H_K said:
@yasotay Exactly. I don’t see a size restriction for conventional armed reconnaissance. And the Blackhawk Down-style SOF mission is odd since FARA can’t carry passengers… so why would it be landing or flying in tight spaces?
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I agree. Note that SOF hasn't been using the Army's previous scout or attack (which are the missions of FARA) helicopters for their missions. Additionally, like you say, there is no requirement for a cabin in the FARA requirements.. What the SOCOM said it wanted in its next vehicle was much closer to the Marines' AURA requirements, although SOCOM wants a cabin to hold 12 equipped troops which is more than Marines want.
 
H_K said:
F-14D said:
Regarding landing areas, remember that Army is concerned with urban and small landing areas for FARA. That's why the FARA rotor diameter is mandated to be no more than 40', one of the reasons that serious doubts exist as to whether a FARA craft can be built that meets all the specifications..
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Is this 40ft requirement really that critical in real life?

It feels rather arbitrary… ultimately a helo with a certain speed/range/payload design requirement is going to weigh X tons, and this weight typically drives the optimal rotor diameter. What if the right answer is 41 or 42 or 45ft?
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That's the design concern regarding FARA. Min. speed/range is specified, along with max weight, which engine with how much power to use, along with rotor diameter. There are worries that it just may not be possible to build a craft that meets all of those.

I think a similar situation occurred with the F-22. Once they got into detailed design for production spec aircraft Lockheed essentially told USAF it could deliver, "Speed, Agility, Range. Pick any two". IIRC, internal fuel was reduced from the original planned amount, and therefore I believe Raptor has less range on internal fuel than the F-15C. Correct?
 
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The SOF community is very tied to both efforts. FLRAA is for 8-12 PAX but the FARA is to be a MH-6 replacement. The Sikorsky FARA offering can put 6 pax into the same space now designed to hold the weapon systems. I would also note that they very prominently portrayed SB>1 air assaulting into an urban environment in the last promotional I posted.
 
yasotay said:
The SOF community is very tied to both efforts. FLRAA is for 8-12 PAX but the FARA is to be a MH-6 replacement. The Sikorsky FARA offering can put 6 pax into the same space now designed to hold the weapon systems. I would also note that they very prominently portrayed SB>1 air assaulting into an urban environment in the last promotional I posted.
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I believe FLRAA requires the ability to transport 12 combat equipped troops plus a crew of two to four. USMC only requires eight, but this is an Army program. For now FLRAA in its Army form doesn't meet USMC requirements. FARA is to replace the OH-58 and part or all of the AH-64s; AFAIK, it is not an MH-6 replacement. As you note , SOF uses the MH-6, not an OH-58 variant). Although a Raider-X with a different interior cabin could use the weapons space for troops, the ability to carry troops is not a requirement for FARA, which is why Bell took the route it did.

In the Sikorsky piece you see that in that urban landing once again they're emphasizing that they don't see a need to flare. I'm sure Bell's marketeers would also produce an animation of their aircraft in an urban environment (they've been depicting Valors operating into villages with stone structures since 2013) if they thought that would help them sell .
 
Most recent Bell video show V-280 formations crossing water to assault a "very small island" with significant military structures on it.
 

Flight Global reporting SB>1 finished its flight testing (behind pay wall). Then again I may be reading into what the title says.​

​

SB-1 Defiant wraps up FLRAA mission profile flight testing​

By Greg Waldron18 January 2022

Sikorsky Boeing DEFIANT LZ Image - EXTERNAL

Source: Lockheed Martin
A Sikorsky/Boeing team has completed mission profile test flights with the SB-1 Defiant demonstrator related to the US Army’s Future Long-Range Assault Aircraft (FLRAA) competition.
 
yasotay said:
View: https://www.youtube.com/watch?v=fqEe-BlXd7Y


Sexy video. Score one to Sikorsky for a video in the environment the Army likes to operate in.
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Interesting choice of clips where Sikorsky is attempting to spin that this is a demo of "hover agility".

Firstly, it seems noteworthy that the pusher prop is engaged and spinning all the way down into the swamp in the landing footage. With its low thrust line and dry clutch, this means that its at full RPM only inches above the ground in this scenario.

Secondly, its been 2 years since first flight and yet we still have not seen any legitimate static hover maneuvering that was demonstrated in the much less sexy flight test videos by the V-280. The rolling maneuvers filmed by the drone in the Sikorsky clip are performed with considerable forward speed such that the static inertia from a stationary hover is less of an issue (and rotor flapping is also thereby somewhat mitigated). Control power in pitch and roll is immense on rigid rotors, but the problem comes down to not "creating a cloud of blade fragments and gray dust"

One of the historical knocks on tiltrotors (mostly based on V-22) is that they are particularly sluggish in yaw, which is mostly true on the Osprey. V-280 remedied this with 50% increased flapping and resulted in a major improvement in yaw rate. SB-1 has its yaw control entirely based on differential collective between the rotors and must overcome the severe moment arm of the pusher prop at the extreme aft end away from the mast. Sikorsky now boldly claims they demonstrated Level 1 HQ, but left out whether or not that actually includes all axes of pitch, roll, and yaw. To date, even on the smaller gross weight ABC aircraft, there has never been published footage of any of them with yaw rates which would meet that requirement.

It would be a very simple task to simply perform the requisite ADS-33 maneuvers from a low hover a la V-280 youtube videos on SB-1 (or S-97!) to put proof in the pudding, particularly after years of such slow, protracted flight testing.

I think its obvious why we still haven't and won't ever see a true apples to apples hover agility comparison between the two.
 
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The prop rotor is in a pusher configuration. That means that the rotor action opposes any change in yaw and pitch. Hence the increase in stability


The countrarotating rotor is of the advancing blade type. That means that roll and yaw divergences are minimized.

I think that's here where SYLM claims for the extra margin in manoeuvrability (power).

Then, I am full on Valor. I don't see how the US armies will do without it. Even if I think that the SB-1 could have been a bit better designed, IMOHO the right choice here is to both designs and build around a new paradigm for air mobility.
 
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The prop is clutched and can be stopped prior to landing. It can also be put into beta for reverse thrust that allows the aircraft to decelerate rapidly, level body; or so says the Sikorsky Boeing Team. I can only imagine that there is significant torsional strain associated with this. I have to wonder what doing so does to the power available as well. I do agree that to date the outside world has not seen any ADS -33 like maneuvers from SB>1. With down select happening later this year, we are told, it is a curious thing.

I suspect that SB>1 is at the very margin of viable scalability for the counter rotating lift offset rotorcraft. While the S-97 and Raider X may be able to do well, a platform this size appears to be fighting physics really hard.

Oh and nice strakes now under the nose. Lateral stability?
 
yasotay said:
The prop is clutched and can be stopped prior to landing. It can also be put into beta for reverse thrust that allows the aircraft to decelerate rapidly, level body; or so says the Sikorsky Boeing Team. I can only imagine that there is significant torsional strain associated with this. I have to wonder what doing so does to the power available as well. I do agree that to date the outside world has not seen any ADS -33 like maneuvers from SB>1. With down select happening later this year, we are told, it is a curious thing.

I suspect that SB>1 is at the very margin of viable scalability for the counter rotating lift offset rotorcraft. While the S-97 and Raider X may be able to do well, a platform this size appears to be fighting physics really hard.

Oh and nice strakes now under the nose. Lateral stability?
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Yeah, the ability to declutch and stop the pusher has always been highly touted - my observation was that for whatever reason, they left it spinning at full RPM all the way to the ground on unimproved terrain in their video. Anecdotally I have heard that the constantly-spinning pusher on S-97 was done so as not to cook the blades from exhaust when in hover, perhaps that's a concern on Defiant as well?

I noticed those new strakes in some previous videos last year as well. As with the original X-2 TD which had poor lateral stability initially, and had the have the tail resized and additional area added a few times, you're probably dead on. Alternately, it could be similar to the F-18 LEX fences used to alleviate vertical tail flutter fatigue - I can imagine the Defiant nose shape and super wide tails may have combined to experience a similar effect. In last years footage you could actually see some of the vortex shedding off the strakes.
 
yasotay said:
The prop is clutched and can be stopped prior to landing. It can also be put into beta for reverse thrust that allows the aircraft to decelerate rapidly, level body; or so says the Sikorsky Boeing Team. I can only imagine that there is significant torsional strain associated with this. I have to wonder what doing so does to the power available as well. I do agree that to date the outside world has not seen any ADS -33 like maneuvers from SB>1. With down select happening later this year, we are told, it is a curious thing.

I suspect that SB>1 is at the very margin of viable scalability for the counter rotating lift offset rotorcraft. While the S-97 and Raider X may be able to do well, a platform this size appears to be fighting physics really hard.

Oh and nice strakes now under the nose. Lateral stability?
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It does raise an eyebrow or two when you contrast how often Sikorsky people talk about those capabilities with the seeming lack of any demonstration 2 years into a demonstration program.
 
IMOHO, they might be choosing to play with pitch settings instead of declutching the pusher prop in order to be reactive to flight conditions. If you declutch the rear rotor, you induce a significant lag in any mitigating action.
 
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Spyclip said:
yasotay said:
Sexy video. Score one to Sikorsky for a video in the environment the Army likes to operate in.
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Interesting choice of clips where Sikorsky is attempting to spin that this is a demo of "hover agility".

Firstly, it seems noteworthy that the pusher prop is engaged and spinning all the way down into the swamp in the landing footage. With its low thrust line and dry clutch, this means that its at full RPM only inches above the ground in this scenario.
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This introduces another consideration. Earlier animations show the pusher being started/stopped in midair, with some altitude under the bird. One of the reasons for this would be that with that prop spinning while on the ground would be a hazard to troops entering/exiting/approaching the vehicle from the rear quarter. Given its position, this would be worse than a regular tail rotor. If they actually have to be on the ground to start/stop it, this could cause restrictions around the rear (not a straight shot at the side doors), or they would have to wait until its stopped/started before they could operate 360° around the craft.
 
www.militarytimes.com

Future vertical lift will redefine the ‘golden hour’

The golden hour is a concept that presumes that some deaths are preventable if appropriate and timely care is provided.
www.militarytimes.com www.militarytimes.com

Not surprising to see the politicians start to roll in hot. Rep. Ronny Jackson, R-Texas, who wrote the piece does not name the aircraft he is talking about, but it should not be too hard to figure the decision he would prefer.
 

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