Comments by "Tara Raboomdiay" (@tararaboomdiay7442) on "Boeing Shows How the Defiant X Is Not That Different From the Black Hawk" video.

The big thing people are forgetting is that the Valor did much better in the demonstrations. It met or exceeded every goal set for the demonstration. It met every schedule Bell promised. Defaint was constantly late, kept failing to meet promised goals when Sikorsky said they would and had problems during the tests. Examples: Valor met the Army's schedule for first flight, Defiant was 15 months late and then soon had to be grounded for more work, slowing the whole program. Defiant came close, but never actually achieved its promised speed, Valor exceed its (higher) promised speed by 9%,, meaning it was 23% faster than Defiant. The first Army pilot flew the V-280 less than two months after its first flight, Defiant didn't do that until 2 1/2 years after its [delayed] first flight. Valor flew far more hours than Defiant. Simply put, one aircraft did a lot better in the demonstrations and inspired much more confidence that a production version would meet or exceeded all the Army's requirements in reality rather than theory. And that's the one the Army chose.
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@njengakim V-22 autorotates poorly because of external compromises. Rotor diameter is smaller than optimum due to size restriction on smaller amphibs in use at the time. Engine Gov't supplied was heavier and burned more fuel than gov't said to expect, which increased weight. XV-15, AW609 and Valor don't have these constraints.
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@bl8danjil Although a naval Defiant would have folding rotor blades, its fuselage is wider than Valor's (and Black Hawk's). More importantly, it is too tall to fit in destroyer and cruiser hangars, and Sikorsky hasn't even tried to show any illustrations of it operating from anything than a carrier or large flat deck assault ship. . Bell has shown how a naval Valor would routinely fold into a space of a folded UH-1Y so as many could fit in a surface warship's hangar as Sea Hawks do now .
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@kennethfharkin One of the advantages of X2 technology over conventional rotor systems (including conventional coaxials) is that as froward speed increases, the whole rotor system slows down so that the advancing blade tips do not exceed Mach 1. This allows an X2 to cruise faster than a regular helicopter, but even Sikorsky acknowledges that it won't go as fast as a Tilt-rotor. They tout other advantages they say they have.
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@bistromathics6 Although advancing blades on both sides work to mitigate the problem of retreating blade stall, but they don't help with what happens if the blade tips go supersonic. The clever trick X2 does is to slow rotor rotation speed as forward speed increases, thus postponing when the tips would go supersonic. This is why an X2 could cruise faster than a regular helicopter, but even Sikorsky acknowledges not as fast as a Tilt-Rotor, partly because tips going supersonic is to something that doesn't concerns a Tilt-Rotor because at high speed sthe rotors are perpendicular to the direction of flight. Regarding VRS,, Tilt-Rotors are subject to this like any rotorcraft. Quite frankly, in V-22 testing insufficient work was initially done in testing the onset of this phenomena, how a Tilt-Rotor (and its software) would react, with tragic results. Once the proper test flying was done, it was found that a Tilt-Rotor is actually somewhat more resistant to VRS that conventional rotors (don't know about X2s, it's newer been tested). More importantly, it was found that it was easier to recover. No special maneuver had to be flown, the procedure is to blip the rotors forward changing their angle to the airflow and the plane flies out of VRS. Its criminal that it took to long to test this.
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@dianapennepacker6854 V-280 has sustained 351 mph which is faster than the cruising speed, though not max speed, of most WWII fighters. To go faster requires more money, and as yet there's no need in a transport. All rotorcraft are subject to Vortex Ring State. The question is how do they react? I've got another comment on this video that talks about this.
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@JAnx01 Defiant-X has nowhere the lift capacity of Chinook. Valor and Defiant-X were both designed to meet the same specified requirements under the same program, FLRAA, they're different technologies to reach the same goal.
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With respect, to add to what bl8danjii wrote, Boeing has never put a helicopter of its own design into production. In fact, of all its own designs, only four airframes of one design ever even flew. Also, Bell designed the V-22, Boeing did the flight control system. This was the same relationship Boeing has with Sikorsky. Boeing's Tilt-Rotor designs (it competed with Bell for the XV-15), did not have the engines in nacelles, but in the fuselage with always powered shafts running to the wingtips. Think how CH-46/47 power their rotors.
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There was no requirement to fit in a C-17/5. Army's plan is if in a hurry, fly it there. This applied to both competitors. Army has not asked for an attack version although USMC might be interested if they bought the transport version in the same way they have the UH-1Y and AH-1Z. Lots of commonality.
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The height is a big factor for a naval version, since there appears to be no way to lower it for storage on surface warships such as a DDG. Whenever Sikorsky shows animation of a naval Defiant, it is always operating from a CVN or a large full flat deck amphib. Bell has shown in illustrations and models how a naval Valor would fold up into a space the size of a folded UH-1Y. They will be able to fit as many V-280s in the hangar of, say, a DDG as SH-60s. Before any one asks why they didn't build it into their demonstrator, the Army doesn't need it and didn't ask for it.
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@rileybriggs4731 I don't think Sikorsky has ever actually demonstrated their promised rapid level deck deceleration. Bell has demonstrated slowing from 220 knots to hover in 45 seconds. One of the V-280 techniques is to tilt the proprotors 5 degrees aft of vertical and raise the nose just 4 to 5 degrees nose up, which really doesn't affect visibility of the LZ. Like you say, raising the nose also really helps in decel.
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@elphi4321 XV-15 and AW609 have demonstrated autorotation. Not all the way to the ground, because all too often, especially the larger you get, even with a successful auto it results in major damage to the aircraft. V-22's requirement was to glide to a Survivable landing because of external constraints gov't put on the design. Since this was the only V-280 in existence, it wasn't worth doing it. I've never heard of the question even being addressed in an X2 design such as Defiant.
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@Matt-yg8ub Everything is more vulnerable in a hover. Actually, the bulk of what you use this class of helicopter for is getting from one place to another. Takeoff, landing and hover only consume a small portion of total operations, and a Tilt-Rotor can hover just as long as a helicopter, just not as efficiently. Like everything, it's a tradeoff for all the other things you get.
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@Matt-yg8ub The press and support staff use Ospreys, but no Osprey is tricked out with the special commo gear the President requires.
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@patrickcamp5885 The Army had no requirement for either aircraft to fit in a C-5 or 17. Although jets are faster, first they have to be available on short notice. Then you/they have to get to where the other is. Then you've got to dissassemble and load and fly to another field equipped to take the C-5. Then you've got to unload and reassemble. then you've got to fly a FCF. And to move more than a few rotorcraft you have to have enough transports. For FLRAA, Army wanted enough range to fly overseas via island hopping as necessary or the way it was done in WWII. Bell has shown a folding version of Valor for naval use, but Army hasn't asked for that.. AAR would be easy on a Valor and probably quite doable on Defiant, although whether it could do it from a jet tanker hasn't been addressed. But really, if you've got enough time the preferred method to send a bunch overseas is by ship.
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@hawk7825 Actually, Sikorsky has been silent about Defiant autorotation.
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@Matt-yg8ub It's interesting that Sikorsky has remained conspicuously silent on the autorotation capabilities of Defiant. Regarding hits, you put some heavy rounds into Defian'ts mast, which being in the fuselage is an easier target, and it's going to undergo serious hurt.
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@Matt-yg8ub Exactly
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@Matt-yg8ub Defiant is narrower, but longer. As far as being the "more nimble" design, the sources for that claim are Sikorsky press releases. In actual flight, it has failed to demonstrate this and in the hover has not demonstrated the agility that Valor did. I'm not sure where you got the idea Valor is less stable in the hove. Hit a Valor in an engine and the damage is away from the fuselage. Hit a Defiant in an engine and you could also mess up the fuselage and rotor mast.
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@bartlettdieball2678 As with everything there are tradeoffs. There's no way anyone can pretend V-280 is not wider than SB>1 or Black Hawk, just like there's no way anyone can pretend SB>1isn't taller-than Black Hawk. The choice for the decision makers is which advantages are worth accepting which penalties. One of the reasons the V-280's width over the rotors is close to V-22's is not because its rotors are so big, it's because V-22's are so small. The optimum rotor diameter for V-22 would have been larger, five feet I believe. However when V-22 was designed, USMC wanted it to operate from all spotson smaller amphibs than we use today. Optimally sized rotors would not meet the safety clearance distance when operating from the two spots abeam the island. That's one of the reasons the downwash is as high as it is. The next step is a virtual prototype like you say, bu tit will be followed by real, physical prototypes. This would have happened if SB>! had proved superior. FLRAA, not just Valor, could go the way of the Comanche if someone in an Administration or Congress, decides they want to make some cuts in the US discretionary budget to look good. Remember we won't see FLRAA IOC until after two more Presidential and three to four House elections which makes it vulnerable to the fact that a lot of people in gov't prefer things they can point to for their next election campaign.
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@deanfowlkes OK, fly one of those carrying 14 troops in and out of a 200 ft LZ with 50 foot trees at either end.
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@deanfowlkes True, but Defiant and Valor are not intended to fit every mission. They're intended to fit the missions Black Hawk (and before that Huey) has been doing for the past few decades in the future. if you always can count on sufficient runway (don't forget to factor in wind) with adequate approach/departure lanes where you need it when you need it, Valor, Defiant, even Black Hawk or any VTOL can't be justified. The thing is, is that a realistic thing to count on?
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@deanfowlkes They are not intended to fit the mission Profile of the Black Hawk, they are intended to take over the Missions of the Black Hawk. What Army is saying is that the missions presently being done by UH-60 [MH-60s are a special case and even there these vehicles will do that better]. will require a different profile in the future. They will routinely require longer range for regular operations Without AAR becasue we aren't going to have as many vehicles or places from which to operate. Additionally, Army can't count on enough tanker support for routine large scale operations. When you put ESSS on a 'Hawk plus add fuel tanks to get range , you're adding weight. The place that comes out of is payload. What Army wants is greater operational range while carrying the full normal payload. Army has not asked for AAR capability for FLRAA. We are going to need more speed for a variety of reasons including not being able to locate them as clsoe to the objective as we can presently. They are going to have to operate in more hot and high locations. They are going to need greater agility. FLRAA will not be magic. There are always tradeoffs. Hangaring for one. Both designs were require to fit in the operational footprint of the UH-60 and Army says that requirement was met. Not sure what you mean by transport space. Regarding "...limited combat roles in impermissible environments...", doesn't every aircraft have that situation? Thing is, these vehicles should be able to operate in combat environments that would preclude some UH-60 operations.
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@deanfowlkes Thank you for your kind words. In actuality, when ocean shipping is not available or not timely enough, ferrying these birds across continents and oceans (note necessarily non-stop) is exactly what the Army intends to do. That's why Army specified such a large minimum unrefueled ferry range, which I'm sure could be extended by installing temporary fuel tanks in the cabin, but AFAIK, that ferry range Army specified is on internal fuel only. Remember, there is no requirement for the FLRAA to be air transportable; they intend to fly them there when the need arises. Now before anyone says this wouldn't be practical across the North Atlantic, take a look at how we moved a lot of fighters to England on WWII without the reliable engines and avionics we have today. .
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@1968gadgetyo That's the FARA program, and it is a smaller rotorcraft. Bell is proposing a n advanced conventional helicopter called Invictus. Both Bell and Sikorsky carry their missiles internally for drag reasons.
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@ameritoast5174 Using Apache's as scouts was the Army's fourth attempt to replace the OH-58 (Comanche was the first), didn't work out as well as they hoped. The FARA program is the fifth attempt. Defiant-X and Valor are too big for what Army wants for this role.
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We already have the Black Hawk, but then we already had the Huey. The environment and our resources around the world have changed and in the future the technology of this 50 year old design isn't going to be able to keep up.
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Sikorsky itself has said they don't see a civil role for X2 technology.
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@danielwhyatt3278 Army wanted first flight in 2017. Valor did that, Defiant was 15 months late, and then had to be grounded soon after that for more work. Army wanted demonstration of top sustained speed. Valor exceeded its promised sustained speed by 9% Defiant came close but never actually dashed to its promised top speed. Army pilots flew Valor 2 months after first flight. That didn't happen for 2 1/2 years with Defiant. When a goal was announced that Valor was to demonstrate it did it when promised. When that was done for Defiant, it missed them a number of times with no explanation. Valor demonstrated high maneuverability in the hover, Defiant demonstrated in forward flight, which is easier. Valor flew 214 hours, Defaint flew 63.9.. Bell showed how if a maritime variant was desired, they would fold up to fit in destroyer hangars. Sikorsky never did. Etc. Valor just inspired more confidence it could achieve its production version goals. X2 is a fascinating concept it's just that right now it seems it's not ready for prime time. Let's hope they do better for FARA, whose performance requirements, and more importantly size, seem better sited to its strengths. Note that Bell is Not proposing a Tilt-Rotor for a number of reasons.
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@gavynhohon2818 Sorry, no. The Navy program, FVL-MS is still in the early stages, Navy is watching to see what happens with Army's program to see if they can leverage off that . After the Navy's order for V-22s for the COD role is finished, the planned production run will be complete. Barring further orders, either above the planned total or more exports, the line will shut down as planned in the next couple of years.
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I don't know if Defiant actually demonstrated rapid decel in level attitude all the way to hover. V-280 demonstrated slowing from 220 knots to hover in 45 seconds. On rapid decel nose om;y lifts ~ 5°, with rotors aft of vertical.
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Russia needed compact helicopters in the past for their smaller landing decks on thiee destroyers. Coakixial does that and also does away with the need for a tail rotor. US didn't need that. Otherwise there's no big advantage. Kaman built the HH-43 Huskie, with intermeshing, not coaxial, rotors which was used for firefighting and rescue at airbases and was pressed into short range rescue during the Vietnam War, but was phased out by the early 1970s. Kaman later built the K-Max, optimized for external cargo lifts, but it newer sold well, and production was terminated. Basically, there hasn't been much interest because coaxials didn't offer enough advantage to justify the extra complexity. X2 is a very advanced type of coaxial which Sikorsky hopes will provide speed and range advantages over conventional helicopters.
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@CaddyJim Sikorsky built a craft decades ago called the S-69/XH-59A. It was an older version of what would become X2 technology It flew a bit earlier the XV-15 Tilt-Rotor. After initial testing, they hung two J60 turbojets on it to boost speed, but even with them it was slower than the XV-15, V-22, AW609 or Valor. And it had a Lot of vibration and even without the jets burned a lot of fuel. . At the completion of its test program it was proposed to modify it into a XH-59B configuration in partnership with Sikorsky.that would have more powerful internal engines, new rotors and a ducted pusher propeller hoping for greater speeds and efficiency. Nothing came of this because Sikorsky was unwilling to share expenses. The only other coaxial I can think of (the HH-43 Huskie was not a coaxial) was the QH-50 ASW drone which was not terribly successful. It was built as a coaxial for the same reason the Soviets did: it permitted operations from smaller helidecks.
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The longer you are on the wing, the less energy you use relative to a helicopter. One important note: Based on experience of the last 30 or so years, Army put in a very strong hot and high HOGE requirement for FLRAA. As a result both Defaint and Valor carry a lot more power than they would need if they were only held to the much lower standard of Black Hawk. That means higher fuel consumption than they would have if held to the old standard. T
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Black Hawk is superb, but it is a 50 year old design and wasn't built for upcoming environments. Look at it this way...this same argument could by used by those who wanted to use the Huey forever.
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@bartlettdieball2678 The Defiant can't just "drop the top rotor". As you can see, the rotors are already very close together. More importantly, the mast and transmission on Defiant or any X2 are massive. Unlike a conventional helicopter (such as Black Hawk) or Tilt-Rotor, the fuselage below the mast and aft is unusable because of the space required for them. Look at Defiant. The entire troop compartment is forward of the mast., unlike Black Hawk or Valor. Where are you going to "drop" that mast to? Now, if you are willing to accept major disassembly/assembly as part of the procedure, you probably could shoehorn one in, although given Defiant's wider fuselage I'm not sure. But that means you'd have to allow major disassembly/assembly for Valor as well. However, the whole point of the Army's specifications is that they don't want to go through that exercise, which is why there is no requirement for FLRAA to be air transportable in normal operations.
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Sikorsky has never addressed hangaring Defiant on a destroyer. For one thing, you've got that non-collapsible mast to deal with. Bell has shown drawings, animations and models of how a naval V-280 would easily fold up into a space as small as a folded UH-1Y, so it would be doable.
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The design is 50 years old. Basically, what is going to be needed in the future can't be done with the Black Hawk, excellent aircraft though it is. For example, "hot and high" wasn't that important when it was design, now it's a big issue. There's no way you could get a Black Hawk to do what Army needs to do in those conditions without a redesign so extensive you might as well start with a clean sheet. .
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@landonmintz4850 The normal operation for a V-22 experiencing total power loss is to glide. Like a lot of large helicopters, it dos not autorotate well from lower altitudes.. This is partly due to external constraints put on the design (rotor diameter, heavier, thirstier engines than promised).
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@samuelphilip915 One of the reasons almost no one trains to the ground anymore (civil or military) is that even if the autorotation is successful, there is often so much damage that it isn't practical.
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@andrewsuryali8540 Although Army doesn't require extreme folding as a Navy version of either would, I wonder it it would want folding rotor blades (manual fold as in UH/MH-60A/L/Ms and USAF HH/MH-60Gs) on a production model of either?. It wouldn't do anything to reduce height on Deviant, but it would permit Valor to rotate nacelles forward, which should reduce its height and width of both when parked for extended period or when in landbased hangar.
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@andrewsuryali8540 Your point is well taken, and I imagine Bell must have shown Army how they'd protect the transmission and tilt mechanism parked or in operations because otherwise that would have been a BIG red flag which someone [read: Sikorsky] would have been happy to point out. Maybe we'll learn more as the protest plays out, because in that process Army gets to disclose more than they have so far.
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