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

[TomcatViP]

It's even a good read.

 

[Grey Havoc]

Without disagreeing in the slightest with the point on folded/hangar size, there's also the issue of maintaining them on austere forward operating locations and how you manage to do any needed work on the SB>1's rotors/rotor hub - stepladder on top of a HMMWV?

Some sort of maintenance robot, autonomous or otherwise? (Send for the Droids!)

 

[DWG]

Without disagreeing in the slightest with the point on folded/hangar size, there's also the issue of maintaining them on austere forward operating locations and how you manage to do any needed work on the SB>1's rotors/rotor hub - stepladder on top of a HMMWV?

I was thinking some more about this, and even with flip-out working platforms at fuselage top height, which ISTR UH-60 has for the forward maintenance scenario, that top rotor hub is still going to be at head height. If Sikorsky/Boeing haven't addressed forward maintenance adequately I can see it coming back to bite them in the assessment.

 

[yasotay]

Without disagreeing in the slightest with the point on folded/hangar size, there's also the issue of maintaining them on austere forward operating locations and how you manage to do any needed work on the SB>1's rotors/rotor hub - stepladder on top of a HMMWV?

I was thinking some more about this, and even with flip-out working platforms at fuselage top height, which ISTR UH-60 has for the forward maintenance scenario, that top rotor hub is still going to be at head height. If Sikorsky/Boeing haven't addressed forward maintenance adequately I can see it coming back to bite them in the assessment.

Ever pulled a ~15 foot tall, very heavy, transmission in a field environment? 16 rotor blades per aircraft to inspect (which is why Bell pointed out in the article they have six) on a regular basis.

 

[VTOLicious]

She's a tall girl... I guess that what they are all thinking.

Here's a shot of the V-280 with some folks. I post it for height comparison. The bigger thing to me is not so much how tall the two are fully ready for flight, but how big they are when folded up.

Without disagreeing in the slightest with the point on folded/hangar size, there's also the issue of maintaining them on austere forward operating locations and how you manage to do any needed work on the SB>1's rotors/rotor hub - stepladder on top of a HMMWV?

 

[F-14D]

In the upcoming FLRAA RFP, it will be interesting to see how the final requirements for two key factors play out, speed and range.

In the former case, if the requirement for speed is significantly lowered (not saying it will be), that could mean one of two things. First, as seems to be happening on some contracts throughout DoD, competition is becoming the end, not the means. In other words, the acquisition folks want there to be a "competition" even if it means compromising mission needs. The more cynical suspicion would be that the fix is in.

The range question would be a bit more complicated. When JMR/FVL got started, I believe everyone was told they could base their ultimate designs and capabilities on the Government' FATE (Future Affordable Technology Engine) that Army was developing separately. However, Army's pace on getting FATE on line doesn't appear they're going to deliver it when FLRAA is going to need it. Bell has already said they're going to go with a Rolls Royce engine for their production V-280s, I don't know where Defiant-X is on this. My point is that if either aircraft has to use a heavier, thirstier engine than was expected, some performance requirements may have to be lowered.

This exact thing happened to the V-22. During design Bell-Boeing were told the Gov't would supply an advanced engine it was going to select, both Pratt and GE were competing with advanced designs. A selection was made, but at the last moment the selection group was overruled and the V-22 team was told they would be supplied with an Allison engine. It was more powerful than the other two engines, but it weighed more and burned more fuel. Bell-Boeing responded that they could work with that GFE engine after some redesign, but with it they would not be able to meet all of their original promises. So the Gov't relaxed some of the requirements, including range.

 

[yasotay]

Superb analysis

 

[sferrin]

 

[F-14D]

Interesting statement in the video ( :011) : "We showed that 230 knots that's what the Army asked for..." . I thought that so far the Army had set the threshold speed at 250 knots, which the SB team had said they'd meet. Am I wrong or has something changed?

 

[yasotay]

Well if they flew today at 230 knots straight and level then that is new. Perhaps they are aware of the requirements.

 

[F-14D]

What I was getting at was the way they phrased it, they were implying they met the Army's requirement at 230 knots. Have they seen the RFP already and the speed requirement is lower, or am I reading too much into this?

I also wonder how much power and torque they were using @ 230 knot level flight.

 

[TomcatViP]

I think the value was lowered in the initial part of the competition to get more entrants. They are also claiming a 70% power setting to reach that speed (from my memory only).

 

[DWG]

For "Hey, we finally cranked her up to 230!" they sure did spend a lot of that clip talking about low speed lifting capability.

And I presume the lift requirement is for more than just *low speed* capability. I don't expect them to get to 230 with a howitzer underneath, but equally I'd expect more than just walking pace.

 

[yasotay]

Only slightly passive aggressive.

 

[_Del_]

For "Hey, we finally cranked her up to 230!" they sure did spend a lot of that clip talking about low speed lifting capability.

And I presume the lift requirement is for more than just *low speed* capability. I don't expect them to get to 230 with a howitzer underneath, but equally I'd expect more than just walking pace.

I think they're just pointing out that their lower disc loading should give better lift capability and hot-high performance assuming both aircraft would get the same shp engines.
OEI scenarios will favour them, too (at least in the case of a sling load and hover).

The entire competition reasserts the old maxim that "what helps you in a hover is bound to hurt in drag/speed department." It's all about where the desires for compromise come in.

 

[yasotay]

No one does OEI sling loads. But I do agree with the comment about compromise. Given the "pivot to the Pacific" range and endurance will likely be at the top of the list.

 

[_Del_]

No one does OEI sling loads

Well, noone plans an OEI sling load You're just going to cut the load, but the lower disc loading gives you more time to recognize what's going on, flash the landing lighta, and perhaps avoid cutting it above or placing it otherwise on the little squishy men wearing green who had helped hook it earlier. They probably appreciate the few extra seconds to run the opposite direction to the rendezvous point.

 

[F-14D]

For "Hey, we finally cranked her up to 230!" they sure did spend a lot of that clip talking about low speed lifting capability.

And I presume the lift requirement is for more than just *low speed* capability. I don't expect them to get to 230 with a howitzer underneath, but equally I'd expect more than just walking pace.

I think they're just pointing out that their lower disc loading should give better lift capability and hot-high performance assuming both aircraft would get the same shp engines.
OEI scenarios will favour them, too (at least in the case of a sling load and hover).

The entire competition reasserts the old maxim that "what helps you in a hover is bound to hurt in drag/speed department." It's all about where the desires for compromise come in.

Defiant-X, if they get it to work, has always been expected to have better hover performance. For one thing, no matter how much extra twist you can put on a Tilt-Rotor's blades, you can't get around the fact that there's a wing there with its attendant weight and is in the Proprotor's downwash. In fact, what Bell says they can do for the hot and high requirement is meet or somewhat exceed the Army's requirement, but not overwhelmingly so. They expect to dominate in other areas. Sikorsky-Boeing's claim for Defiant, OTOH, is a HOGE at an altitude much greater than the Army requirement. It's all a tradeoff between capabilities, assuming both meet their promises.

BTW, the V-280 has already demonstrated carrying external loads.

 

[F-14D]

I think the value was lowered in the initial part of the competition to get more entrants. They are also claiming a 70% power setting to reach that speed (from my memory only).

That would be something I worry about, making competition an end rather than a means. They had four entrants, and at the time they cut it down to just Valor and Defiant, Army said they werren't going to a full and open competition because they felt that those two were the only ones who would be technically capapble of meeting the requirement.

 

[yasotay]

Never underestimate the Army's myopia. This is the same service that at the US entrance into World War 2 told Congress that the Horse Cavalry had to be doubled in size. The Army does h-e-l-i-c-o-p-t-e-r-s. If the requirement that is written after analysis is too demanding for anything that looks like a helicopter, well ...

 

[Hydroman]

As an example, the Comanche could have gone into service as its intended light attack/scout role but the Army messed that up by piling on all nice to have features/capabilities up front, bringing the weight way up, adversely affecting engine and vehicle performance then cancelling the program all together, they could have grown its capabilities gradually over time.

 

[Grey Havoc]

Yes, trying to increase capabilities while decreasing costs using COTS systems and components turned out to be a major blunder indeed.


On another note:

US Army sets timeline to design new long-range weapon

After an FY22 competitive shoot-off, the Army will kick off development of a long-range precision munition for its future aviation fleet.

www.defensenews.com

 

[yasotay]

Bell V-280 Valor tech demonstrator retires from flight

The V-280 Valor first flew in December 2017 and is now retiring from flight as Bell prepares to compete to build the Army's future long-range assault aircraft.

www.defensenews.com

"...Ryan Ehinger, Bell’s vice president and program director for FLRAA, said in the statement. “Ultimately, the Army doesn’t send warfighters into battle riding in the back of digital models and so we thought it was important to bring that physical proof,” he said."

This is going to be a masterful passive/aggressive fight over the next 12 months.

 

[shin_getter]

Never underestimate the Army's myopia. This is the same service that at the US entrance into World War 2 told Congress that the Horse Cavalry had to be doubled in size. The Army does h-e-l-i-c-o-p-t-e-r-s. If the requirement that is written after analysis is too demanding for anything that looks like a helicopter, well ...

A larger animal capable of carrying a 37mm HV gun is needed to overmatch combustion powered armored threats while preserving the force's capability for rapid shock action. Sounds like a reasonable developmental project.

 

[yasotay]

Never underestimate the Army's myopia. This is the same service that at the US entrance into World War 2 told Congress that the Horse Cavalry had to be doubled in size. The Army does h-e-l-i-c-o-p-t-e-r-s. If the requirement that is written after analysis is too demanding for anything that looks like a helicopter, well ...

A larger animal capable of carrying a 37mm HV gun is needed to overmatch combustion powered armored threats while preserving the force's capability for rapid shock action. Sounds like a reasonable developmental project.

At one point I had a white board in my office where I had laid out all of the reasons a horse was better than a tank.

 

[Rhinocrates]

Never underestimate the Army's myopia. This is the same service that at the US entrance into World War 2 told Congress that the Horse Cavalry had to be doubled in size. The Army does h-e-l-i-c-o-p-t-e-r-s. If the requirement that is written after analysis is too demanding for anything that looks like a helicopter, well ...

A larger animal capable of carrying a 37mm HV gun is needed to overmatch combustion powered armored threats while preserving the force's capability for rapid shock action. Sounds like a reasonable developmental project.

Ahem...

 

[aim9xray]

One word. One word only, Vasily.

Sharknado!

 

[robunos]

Nahh . . .







cheers,
Robin.

 

[Spyclip]

Did anyone else feel the most recent SB1 propaganda video was exceedingly odd? Of course Sikorsky had to shout from the mountain top that they achieved 230 kt, but they merely showed old B-roll footage of previous Defiant and Raider flights, and then cut to Bill Fell's head (looking up from below?) in the cockpit talking into a radio, but its not even immediately obvious if he is in flight.

I will admit I was surprised to hear they actually flew the thing again, rumors seemed to indicate they had retired before the end of 2020. If you total up all the flight hours across every X2/ABC aircraft ever produced (including XH-59A), the entire fleet has averaged approximately one flight hour per month.

 

[Spyclip]

And I believe that technology is already in use on other rotor blades.

Who are the other companies with an automated fiber laying capability for something the size and complexity of a rotor blade? I know there are plenty of companies including Airbus and Boeing who are exploring different applications for AFP, but I don't know of any rotor blades being produced this way except the Boeing ones for this project. And 11 days for blade lay up is pretty impressive, now that they've got it working.

For the record, both the Bell 429 and the AW609 blades have been built using automated fiber placement for well over a decade. This was not a new process, and it was not the Army that "forced" them into using it. They presented it as an advantage to meet the required rates for production and claimed it would not be an issue.

It was Boeing hubris that caused this snafu, and not understanding the process for blades vs fuselage construction. Sikorsky mind-blowingly allowed Boeing to design and fab blades and blade tooling for the program. The Boeing guys at Mesa completely dropped the ball with the spar mandrel design and made some very basic composite-design oversights with its layup.

My personal and totally unverifiable belief is that they had control and vibration issues and used the blades as an excuse to delay first flight

It's a pretty elaborate hoax to spend two years trying to produce a rotor blade, then abandoning the tooling and replacing it with a different stiffer material just to hide vibration issues which everyone already suspects they will/would encounter... And I don't know why the Army would go to bat for them on the tooling issue afterward as they did.

The vibration issue is inherent to the X2 implementation of rigid pylon mounting with fuselage-based AVC that Sikorsky keeps building. They attempted to make a new revision blade for the S-97 to alleviate some vibration by reducing the tip twist as well as fix structural problems that stemmed from their supplier (Eagle Tech). It didn't work, and the S-97 has actually flown progressively slower in every flight since their installation. I do not believe the SB1 blade material changed, only some of the ply shapes and tooling - particularly the mandrel rigidity.

The Army was looking to keep the dog and pony show going to help provide less ammunition for a subsequent protest (despite the entire program running under an OTA). They still know all about the ludicrous vibration on all of these platforms as well, yet have you seen them address it with any commentary about that or the lack of total flight hours?

Plus, while the S-97 has had problems, building the blades hasn't been one of them.
...
Considering how limited the envelope expansion on the S-97 has been in over six years, ...

S-97 beat the speed requirement for FARA two years ago without issue. They had an early flight control software issue which resulted in the crash in 2017 after the rotors kissed. That understandably delayed the flight test program for the other aircraft. Since meeting the goals, it hasn't flown much. They haven't shown much interest in flying on their own dime since then.

The idea the S-97 met its goals is humorous. Vh from Sikorsky themselves was 240 kt. To date they have shown maneuvers typically less agile than any conventional helicopter of similar gross weight. There have been no demonstrations of anything approaching ADS-33 level 1 handling or any of the extreme attitude-hold magic they talk about all the time.

 

[yasotay]

The lack of any claims to having met ADS-33 with either program (beyond simulation), which you think would be rolled out with great fanfare, is alarming.

That said senior leaders and investors are not overly willing to take chances with demonstrator aircraft, especially when one of them got a boo boo.

 

[Spyclip]

The lack of any claims to having met ADS-33 with either program (beyond simulation), which you think would be rolled out with great fanfare, is alarming.

That said senior leaders and investors are not overly willing to take chances with demonstrator aircraft, especially when one of them got a boo boo.

Indeed. Instead of actually performing real demonstrations, Sikorsky has interspersed computer generated snippets of the S-97 performing agile maneuvers between clips of the actual flight footage in multiple public videos they have released.

They have also had the audacity to actually increase the speed of the footage of the Raider performing a strafing hover circle in one of their videos, as if nobody would notice.

 

[VTOLicious]

The lack of any claims to having met ADS-33 with either program (beyond simulation), which you think would be rolled out with great fanfare, is alarming.

That said senior leaders and investors are not overly willing to take chances with demonstrator aircraft, especially when one of them got a boo boo.

Indeed. Instead of actually performing real demonstrations, Sikorsky has interspersed computer generated snippets of the S-97 performing agile maneuvers between clips of the actual flight footage in multiple public videos they have released.

They have also had the audacity to actually increase the speed of the footage of the Raider performing a strafing hover circle in one of their videos, as if nobody would notice.

Well, almost exactly 10 years ago I found the achievements of another experimental helicopter program pretty impressive...

View: https://youtu.be/I14weyVGxCI

 

[Moose]

The lack of any claims to having met ADS-33 with either program (beyond simulation), which you think would be rolled out with great fanfare, is alarming.

That said senior leaders and investors are not overly willing to take chances with demonstrator aircraft, especially when one of them got a boo boo.

V-280's team touted ADS-33 Level 1 demonstration results in 2019

Amphib Boxer soon to be sidelined again for 18 months of maintenance - Breaking Defense

A new government contracting notice says the ship will undergo maintenance from April 2025 through October 2026.

www.google.com

 

[Spyclip]

The lack of any claims to having met ADS-33 with either program (beyond simulation), which you think would be rolled out with great fanfare, is alarming.

That said senior leaders and investors are not overly willing to take chances with demonstrator aircraft, especially when one of them got a boo boo.

V-280's team touted ADS-33 Level 1 demonstration results in 2019

Amphib Boxer soon to be sidelined again for 18 months of maintenance - Breaking Defense

A new government contracting notice says the ship will undergo maintenance from April 2025 through October 2026.

www.google.com

Ah, I assumed his "either program" remark was referring to SB1 and S-97.

V-280 demonstrated Level 1 handling qualities in pitch, roll, and yaw 2 years ago. It did most of those maneuvers at the Fort Worth air show publicly, to boot.

15 degrees of rotor flapping solves the problem that plagues the heavier V-22 @ 10 degrees.

 

[F-14D]

One of the other developments in the advance of Tilt-Rotor technology is in wing sweep. The wings on previous Tilt-Rotor designs have had the wings have some forward sweep out of concern for possibility of potential impact of the proprotors with the leading edge of the wing in forward flight. The V-280's wing doesn't.

 

[Spyclip]

One of the other developments in the advance of Tilt-Rotor technology is in wing sweep. The wings on previous Tilt-Rotor designs have had the wings have some forward sweep out of concern for possibility of potential impact of the proprotors with the leading edge of the wing in forward flight. The V-280's wing doesn't.

Believe it or not, the straight wing was implemented almost entirely for cost reasons. The manufacturing methodology used with thick carbon skins, large cell carbon core, and paste bonds plus the tooling for a linear structure is drastically cheaper to build than the V-22 or 609 wing design.

The forward sweep on other tilt rotor designs is partially for flapping clearance, partially for aeroelastic stability/wing bending modes, but also CG/AC balancing since the nacelle pivots the rotor and engine masses as a single large unit.

Airplane mode flapping on V-280, particularly with the increased physical flapping capability, was kept in check by advanced flapping controller logic to bias more authority at the critical wing azimuths. In the end I don't think that was ever actually needed.

 

[F-14D]

One of the other developments in the advance of Tilt-Rotor technology is in wing sweep. The wings on previous Tilt-Rotor designs have had the wings have some forward sweep out of concern for possibility of potential impact of the proprotors with the leading edge of the wing in forward flight. The V-280's wing doesn't.

Believe it or not, the straight wing was implemented almost entirely for cost reasons. The manufacturing methodology used with thick carbon skins, large cell carbon core, and paste bonds plus the tooling for a linear structure is drastically cheaper to build than the V-22 or 609 wing design.

The forward sweep on other tilt rotor designs is partially for flapping clearance, partially for aeroelastic stability/wing bending modes, but also CG/AC balancing since the nacelle pivots the rotor and engine masses as a single large unit.

Airplane mode flapping on V-280, particularly with the increased physical flapping capability, was kept in check by advanced flapping controller logic to bias more authority at the critical wing azimuths. In the end I don't think that was ever actually needed.

Good to know. Thanks!

 

[yasotay]

US Army triggers competition for future long-range assault aircraft

The Army has released its request for proposals to two industry teams to build its future long-range assault aircraft. According to FY22 budget documents, it also laid out a schedule to reach a first unit equipped by FY30.

www.defensenews.com

FLRAA RFP is out. A very aggressive (by DoD standards) schedule. Little specific data other than 230 (threshold) to 280 (objective) knots airspeed.

 

[Spyclip]

Rumor has it that that 6k/95 mid mission HOGE may have been relaxed