Any day now, I expect the SB>1 team to excitedly put out a press release that proudly proclaims as one of their accomplishments in the two years since their first flight that their vehicle has required far less fuel than the V-280.

One of the requirements for FLRAA is that the aircraft has to to be able to fit the same number of their craft into a given space as the UH-60.. Both competitors meet this requirement. Another is that they have to meet the agility requirement. In some areas V-280 has already demonstrated that it exceeds thisrequirement. I don't know about SB>1 yet.

FWIW, here's a comparison of the footprint of the V-280 vs. UH-60


https://cimg1.ibsrv.net/gimg/pprune....095f2b39fe.jpg

Isn’t Time Running Out?
 

The FLRAA RFP responses are due in less than three months. Isn’t time running out for the SB>1 to prove it can meet the US Army threshold requirements?

For some reason, Army has been going through all kinds of gyrations to keep Lockheed & Boeing in the competition despite its consistently disappointing performance (although they do get points for creative press releases). SB>1 was built for the "technology demonstration" phase. One wonders, in the two years since its [delayed] first flight and having only flown ~26 hours how much technology has actually been demonstrated The next phase is "risk reduction". This is what Defiant-X is being touted for, After that comes the competition to actually go to production.

I guess they're not going to do that much more with the SB>1 airframe. The consensus here seems to be that it'll never reach its promised speeds. I don't know, but then again S-97 Raider (to be replaced by "Raider-X") never reached its promised speed, either. I wonder if Army is thinking that if they don't have two "competitors" regardless of how they're doing, Congress, not paying attention as usual, will complain about the lack of competition and that could hurt funding.

I didn’t think it was going to be another competition of flight demonstrators. Isn’t the next competition phase just a proposal?

Apart from some US Army bureaucrats, I don't think anyone cares.
The Biden administration is trying to come up with a coherent approach to China without breaking too many eggs. It is obvious the Afghanistan withdrawal will be prelude to a mess at best.
After the very public failure in this small arena, no one can trust the Pentagon claims about their strategy for deterring China.
The US needs a 'come to Jesus' moment, to admit they have not won a war in 75 years and that more of the same will only stretch that string to a century or more.
Hopefully the Biden team will catch on before the NATO allies do.

The phase they''ve been in for the past year is the Competitive Demonstration and Risk Reduction, for which Bell got $84 million and Sikorsky got $97 million, which will “include initial conceptual designs, requirements feasibility and trade studies using model based systems engineering", In other words, they are spending almost as much time analyzing the data they got from the JMR-TD phase (in which SB>! barely flew) as the entire length of that first phase! "Ultimately, this information and industry feedback are vital to understanding the performance, cost, affordability, schedule risks and trades needed to successfully execute the FLRAA program". This will, “will inform the refinement of the capability requirements, system performance specification and identify risk areas.” Translation: "We're going to push lots of paper so we don't get protested too much". Not sure if there will be any required flying during this phase. Frankly, though, unless they can get some serious flying in, even at their own expense, I don't see how the selection could go to Sikorsky-Boeing

After this phase comes the actual request for Best and Final Offers and selection scheduled (for now) in 2022. Then there will be more design reviews, and reviews, until delivery of the prototype of the winning design in 2025, and delivery to the first Army unit in 2030. No I don't know why the Army wants it to take so long.

I think the Army sees keeping both V-280 and SB>1 funded during the current concept development and risk reduction phases as political cover and investment to make sure no one can protest that it wasn't a good competition when V-280 is chosen next year, despite Bell not being the incumbent VTOL supplier for the Army. Next year will be crucial for the X-2 concept... I'm assuming SB>1/Defiant-X will stop work and all X-2 hopes and dreams get pinned to Raider-X. If that thing can't have first flight on schedule and make Vh in a reasonable amount of time (less than two years, lol) then it's toast and so is the X-2 platform. A decades' worth of engineering effort and a ton of money for zero return.

Interesting tidbit I missed before... when Sikorsky Boeing unveiled Defiant-X in January, they said it was optimized for, "...speed where it matters". To me that seems to say, "No, we won't be as fast as we said we would be, but it's not important anyway. Pay no attention to that man behind the curtain". What they seem to be trying to push everyone to focus on is how fast they promise they will be able to decelerate from whatever speed they do achieve while staying in a level attitude (have they actually demonstrated that in the nearly six years since S-97 first flight?) by putting the pusher in Beta.

Or am I reading too much in?

So, is the consensus that the Defiant flight test is over, and the aircraft was probably grounded even before 2021?

If that really is true, the entire program smacks of a mind-boggling study of incompetence and engineering failure, not to mention the dubious absolute lack of coverage on this fact by the aerospace/defense "journalism" community.

I cannot imagine the 280 being chosen. Yes it is fast but that’s it. It would make a nice semi-strategic transport between FOBs with secured landing sites but I cannot imagine how that bird will perform in a hot-LZ, possibly taking fire and survive like a Blackhawk (or even Huey in the old days) can. It will have massive down wash, a bigger footprint, no clear field of fire for a door gunner due to the nacelles, etc etc... but yes it is fast....

Sorry to burst your bubble, if you looked, you would notice that the 280 nacelles don't tilt for that very reason.
Bell improved the design so that they split and pivot upwards, so there is a clear field of fire.
It is a very different ship to the V22.

“It is fast but that’s it.” Hmm… well, let’s see, compared to the V-22, V-280 is smaller, has much lower disk loading, has increased low speed agility (meets the Army requirements for a tactical transport), has fixed nacelle on top of the wing for clear field of fire, and myriads of design and cost improvements based on 500,000+ flight hours of V-22 experience plus the development efforts of the 609 and JMR-TD tiltrotors and other aircraft in the last 30 years. It is not a V-22 painted olive green.

I cannot imagine the Defiant-X being chosen. Can’t reach Vh, no publicly demonstrated low speed agility, only dozens of flight hours, no demonstration of any required capabilities, no flights with Army pilots, no field history, and no field history of any ABC aircraft. None. Since the XH-59 flew and didn’t meet it’s design goals there have been three more rigid coaxial aircraft and a grand total flight time in the mid-hundreds of flight hours… combined. Three of those vehicles don’t appear to have met the engineering goals and one was only ever designed to fly fast with very limited maneuver requirements. Any projections of costs, maintenance requirements, service suitability are just made up bunk. Sikorsky needs a new strategy and product in the pipeline to maintain a viable engineering department because the X-2 has been a 15 year long dead end.

I agree, slightly less than V22...I said nacelles, what I meant was the wings and it’s nacelles. If you are landing in slightly lower terrain than the area around you (clearly not ideal but sometimes no other options), you probably have more restrictions than with a regular rotor disc. And how vulnerable is such a split nacelle already for small arms fire? And that times 2 as you have 2....

You never saw me writing that they should choose Defiant! ;-) Fully agree with your arguments. I think both contenders cannot perform and survive (at the moment) how a Blackhawk can in tactical operations..(no, I am not a Blackhawk pilot either...) there was too much Focus in both designs on „just“ being fast, which should, to my opinion, not be the main driver for helicopter operations. They should be flexible, maneuverable, and tolerant to ballistic damage and if the new designs then are a bit quicker and have larger range, that’s nice...

Casper

The first time they used the UH-60 in an airborne assault into contested territory (Grenada) they lost three aircraft at one LZ. The 280 has demonstrated that it meets all of the Army's agility goals while being twice as fast and twice the range of existing assault helicopter. With its characteristics the V-280 can pick and choose where to insert the troops while the shorter range 60 and Defiant will most likely have to pick the first (and most likely) one they get to.

500 Hours?
 

https://newatlas.com/military/sikors...ility-us-army/The Sikorsky PR team is really stretching credibility with the statement ”Sikorsky has been flying and testing X2 Technology for more than a decade, accumulating nearly 500 hours”

To get to this number Sikorsky needed to add the flight test time on four different X2 aircraft, plus ground runs and multiple ground test benches for over a decade;

X2 Demonstrator: 22 Flight Hours

S-97 Raider Ship 1: 20 Flight Hours (Crashed)

S-97 Raider Ship 2: 100 Flight Hours

SB>1 Defiant: 30 Flight Hours (estimated based on 26 FH in Jan 2021)

Total for all aircraft: 172 Flight Hours

So the remaining 328 Flight Hours advertised by Sikorsky were accumulated on ground runs and test stands.

Compare this to the “single” Bell AVCD V-280 aircraft, which since it’s first flight three years ago has accumulated over 216 real Flight Hours.

I didn’t post this last month when the article came out, because I felt I was beating a dead horse. But it appears hyperbole, smoke and mirrors, and snake oil are all part of Sikorsky‘s sales pitch.

The engineers at Sikorsky are working their tails off to make this aircraft work. But there comes a time when do you need to look at the data with eyes wide open.

This seems a rather silly thing to try and poke at.

In a (very rare) defilade-type position you describe, the larger and lower spinning rotor of a conventional helicopter causes essentially the same occlusion within a couple of degrees, but over the entire circular arc instead of just the narrow aspect wing area. This difference is accentuated due to fact that the gun positions are largely forward of the wings.

The dual engine and pylon arrangement and the tiltrotor platform has proven itself in combat with the V-22 for going on 15 years now, from both small and heavy arms fire. Just look up Rooster 73 in south Sudan, or the DFC awards for the Osprey pilots flying in Afghanistan in 2012.

Claiming 500 hours is just like the claim that the S-97 can cruise at 220kt....or that any of the X-2 ships are capable of low speed agility Level 1 HQ....or can perform level body acceleration/deceleration....or have manageable vibration....etc etc

Facts are unimportant when you can just repeat your marketing bullet points ad nauseum and the media parrots them on command.

I've zero expertise in this area, but a recent comment in a defense publication caught my eye.
It claimed the SB-1 was preferable because its rotor diameter was similar to that of the UH-60, allowing use of common landing zones.
This seemed somewhat over the top to me (or possibly clutching at straws).
Can anyone with experience in this space provide some insight please?

Check out Commander Cody’s earlier post.
 

[isQUOTE=Commando Cody;11007479]FWIW, here's a comparison of the footprint of the V-280 vs. UH-60


https://cimg1.ibsrv.net/gimg/pprune....095f2b39fe.jpg[/QUOTE].

Check out Commander Cody’s earlier post

.

Check out Commander Cody’s earlier post[/QUOTE]

And since Sikorsky hasn’t released a rotor diameter, here is a top down photo of SB>1 and an H-60 for visual comparison. There’s a difference in footprint between them all, but it’s largely the orientation of the aircraft that’s different, not the area itself.

(The red circles are the same, looks like SB>1 rotor diameter is ~3 feet larger in area than an H-60?)
https://cimg1.ibsrv.net/gimg/pprune....145ce0262.jpeg

Interesting!
Looking at the two footprints I'm wondering a bit if cabin volumes between the two are comparable by any means?!. While the fuselage of the V280 looks markedly slimmer than the Blackhawk, SB-1 looks MASSIVE compared to it.

Not surprising when you consider that on the V-280 the fuselage only needs to hold the crew and passengers.

Compared to the SB>1 fuselage which must house engines, gearboxes, fuel, in addition to crew and passengers.

I was referring more to the width of the fuselage. While the V280 fuselage is narrower than the UH-60, the SB1 appears to be much wider. Length of the cabin obviously can't be determined from the overhead shot.
So it might be that V280 has a long but narrow cabin while SB1 has a wider but shorter one.
It seems I haven't seen cabin dimensions of the two so far. Any numbers out there in the wild?

No cabin dimensions for either aircraft I can find. But lots of photos of seating layouts for mock-ups and artist renderings. Based on seating layout of the V-280, the cabin appears to be longer and narrower than the SB>1.
https://cimg9.ibsrv.net/gimg/pprune....b5bf47eed.jpeg
https://cimg0.ibsrv.net/gimg/pprune....490f65587.jpeg

While both seating layouts have benefits and compromises, I find it odd the SB>1 layout does not have provisions for the side gunners like the V-280.

Fuel burn - Let's say a fully loaded V-280 cruises at 280 knots. A fully loaded Defiant maybe 220? knots. Because the Defiant is slower, that makes its fuel burn look better than it really is. A fixed wing provides 15? lbs of lift per lb of thrust - a clear advantage for the V-280 Valor. Does Defiant have to carry more fuel to meet the Army range requirements? That would be a significant penalty, both in terms of weight, and in fuel cost.

A twin main rotor design has more drag than a single main rotor design. The close spacing of the rotors is intended to minimize this extra drag. This extra drag can be overcome with brute force, but this means burning more fuel. The same applies to the FARA program. Does DOD want to procure high fuel burn aircraft for the next 30 years?

Defiant-X definitely has a lower cruise efficiency (L/De) than V-280 but actual fuel consumed also depends on cruise speed and engine SFC, etc. They appear to have been successful in talking down the speed requirement which would also reduce the power required to cruise. Is it enough lower to overcome the poor L/De (relative to a tilt rotor) and require less fuel to cover the same distance as V-280 but at lower speed? Unknown. Could well be slower AND take more fuel to meet the mission radius. They haven’t said what engine Defiant-X will use and that’s an important variable in the question.

Of course, Defiant (nor Raider) can hit 230 knots in level flight, despite that speed being inside design requirements for both demonstrators. So we’re discussing the fuel efficiency of a solution that hasn’t been shown to meet the speed requirement, regardless of power/fuel consumed.

Regarding cabins of the two, something became apparent around the time they were engineering the X2 demonstrator: I guess because of the space the mast and transmission needs, on an X2 all of the cabin has to be forward of that location. So the SB>1/Defiant-X cannot use as much of it fuselage length as could a conventional helicopter or Tilt-Rotor. This would drive them to a wider cabin.

Whatever the reason, this thing is huge. It will make a great target, based on the ponderous 'agility' demonstration video aired earlier.

A wider fuselage means more airframe drag.

The question remains: how important is all this “cruise” stuff.... you can take a Hercules for that part. For a tactical helicopter you need surviveability, agility, low costs, small footprint, good OGE power margins, low, easy maintenance... that kind of stuff and yes maybe a bit quicker than the one it is replacing....

How exactly do you plan an air assault mission to land a Hercules without an airstrip? That argument falls flat on its face instantaneously.

You also forgot about range, unsurprisingly. That has exponential cascading effects on logistical footprint.

Based on your post, I can’t understand what point you are trying to make. What evidence do you have that the Defiant can eventually achieve any of the attributes you listed? Especially in lieu of Sikorsky and Boeing success rate to date on proving Defiant capabilities in flight test.

What "cruise" gets you is less time exposed to enemy fire en-route, Also the ability to operate higher, out of the range of light weapons. It allows you to do more with less assets and with fewer required bases because the reduced transit times mean you need fewer assets in total and fewer bases since the vehicles can get there in the same time from twice as far away.

Al of the other things you mentioned are already incorporated int the requirements, they've always been there. What newer technology buys is all that plus greater speed, range, responsiveness, versatility and effectiveness.

CV-22 Crew
 

Anyone notice that on the Osprey thread, the latest post #642 refers to the last CV-22 being delivered at Cannon AFB to its "two assigned crewchiefs".Typo??

CV-22B normally flies with crew of four: pilot, co-pilot and two either "crew chiefs" or "flight engineers", depending on the source from which you get the information.

Referencing the Maintenance Squadron comments in the press release this is correct, there are two crew chiefs assigned to each airplane, a primary "dedicated" one, and an assistant CC. They are not flight crew members. The airplane becomes their responsibility for airworthiness, thereby giving them "ownership" in a sense.

Wider fuselage also means more of the rear prop is occluded and not all the airflow entering the prop from the fuselage is going to be very predictable. Perhaps this is part of the speed deficit of Raider and Defiant? The X-2 demonstrator was a skinny dart of an airframe by comparison.

In any case, is it just me, or does anyone else see this thread pop up and read it as "Sikorsky SB-1 flies for last time"?