Comments by "Tara Raboomdiay" (@tararaboomdiay7442) on "Defense News"
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In my opinion, there's one factor that I suspect played a large part in the decision that only a few people have touched on: The relative achievements of the two technologies in the demonstrations.
Bell would announce what they were going to do next and then just go out and do it. In a straightforward manner and didn't parse language when they met or exceeded all the requirements and all of their promises. They did what they said they'd do when they said they would, and except towards the very end thy didn't take snipes at the other guys.
The Defaint (and the S-97, for that matter) were late, would announce an upcoming goal and when it would be demonstrated and then when it wasn't achieved they'd just be silent about it. For example, the Army's schedule for JMR-TD was first flight in 2017, a year's flight demonstrations where the technologies would demonstrate their promised capabilities as they related to Army criteria in 2018, after which Army would spend 2019 evaluating the test data before deciding in 202 which technology to take further into development. Valor flew as scheduled in 2019. They couldn't get Defiant into the air until 2019, and then in a relatively short time they had to ground it for more work before resuming demonstrations. Valor flew its first Army pilot two months after first flight. Defiant took nearly 2 1/2 years. Defiant flew far fewer hours than Valor.
Sikorsky kept saying it was OK because they were providing lots of data from simulations. The thing is, until you actually go out and do the thing for real, there's no way to validate whether your simulations are accurate. For example, Bell could have said the V-280 could do Mach 2 because they did it in simulations. Valor would show high agility in the hover, Sikorsky would brag about their low altitude banks , but leave out the fact that they were moving forward at a good clip, which makes high bank angles easier. They'd talk about their ability to rapidly accelerate after takeoff in a level attitude thanks to the prop, but the videos would show it heading out nose down just like a regular helo. Or, they would announce a new sustained speed achieved, but leave out that it was achieved in a shallow dive. And so on and so forth.
Now my point in this case is not to address the relative performance advantages/disadvantages of the promised capabilities of the two technologies. Defiant, for example, if a production aircraft meets the promises, will HOGE hot and high much better than Bell's promises for Valor (although it will meet the Army's requirement). Valor is faster. What I'm getting at is that if in addition to relative promised performance, they're trying to decide which technology generates more confidence that it'll deliver on its claims, from the demonstrations Valor wins that hands down. Some might say that's because there's less experience with X2 but so what? That's not the taxpayers problem, and it further buttresses the Army's choice.
Army is not going to come right out and say that, they're going to wait for the protest to be heard and then use what happened in the demonstrations as further justification for their choice.
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@dct124 If I recall, int hose articles Sikorsky talked about what happens if the pusher got shot off, unlike a conventional helicopter, it can still function. Now if you're hit hard enough to blow a major portion of the tail off, pretty much anything is going down.
Carrying an external load will slow anyone down, including Defiant. Yes, although Valor can lift an external load operatic in rotorborne configuration (mighty handy for takeoff and landing), it will probably operate in intermediate configuration if they want max speed while carrying a load faster. BTW, the V-22 hold's the world's record for speed when carrying an external load. Frankly, though moving a decent external load at speeds above 100 knots is not that operationally useful because of the loads placed o the cargo and effects the hanging cargo place onthe carrier.
Well, another reason was lower risk. Valor just got out there and did whatever was asked of it whenever it was asked of it while Defiant had a troublesome t demonstration record, and kept missing achieving datapoints on their announced schedules.. Here's just one example: the original JMR-TD for FLRAA called for first flight in 2017, a year of flight test/demonstrator in 2018, a year of data reduction and analysis in 2019, with selection of who would proceed to the next phase, viruatl and real world prototypes [remember, these were demonstrators.not prototypes) in late 2019/early 2020. 2020. Valor flew in 2017, did the demonstrations on time and the flew beyond what was required. Defiant not only didn't fly in 2017, they couldn't even get it into the air until March of 2019. And then it had to be grounded for problems a few flights after that. Its demonstration program was troubled and caused the whole program to slip.
So it's not too surprising that they'd lean towards for Valor even on just perception of lower risk, even discouraging the performance differences
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The OH-6 was indeed better. IIRC, on the initial award it looked Hughes bid below cost in order to get in for follow-on buys. Then, when the initial buy was completed Hughes price for follow-ons was dramatically higher. This embarrassed the customer, and if there's one thing you Never do is embarrass the gov't; it's memory is long. Even though it would result in pries higher than what Hughes was asking then no matter who won, a new competition was ordered. Bell had redesigned their buttt-ugly YOH-4 into the Model 206A JetRanger, one of the most beautiful helicopters ever built. They bid a military derivative of what was now essentially a civil design,, Faichild-Hiller declined to rebid their OH-5, which had come in second the previous time around and concentrated on their civil derivative the FH-1100. Bell's design was selected quite posibly because teh gov't wasn't mad at them.
The Cheyenne would have more capable than the Cobra, but it kept having development problems and its schedule was continually slipping. With Vietnam going hot and heavy Army just couldn't wait until the uncertain date when it could be fielded. . Air Force lobbying against it didn't help either. So a new competition was held for an interim gunship that could be fielded quickly until Cheyenne could eventually show up, and Bell's model 209 was the clear winner. If Cheyenne had met its schedule there would have been no Cobra, and if it hadn't been canceled there wouldn't have been so many Cobras
The reason they didn't give out ll the details of the decision is that they were preparing for the inevitable protest. .
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@irvhh143 Hmm, twice the speed, far greater range, faster accel/decel, larger payload, much greater ability to HOGE in hot and high conditions, etc. Sounds like more than a "minor" increase in performance to me.
Actually, the Chinook is a surprisingly good autorotator, especially given its size. I should point out that every autorotation does not necessarily mean you end up with a soft, gentle landing. How much autorotation capability is one of the tradeoffs in design. For example, the UH-1 reportedly autorotated better than the UH-60, but no one says we should have stayed with the Huey. As to what's Valor's autorotational performance, all we know for sure at this point is that Bell says it has the capability. We'll have to wait for a prototype to see. The aircraft flown so far was just a technology demonstrator,. Come to think of it, what's Defiant's performance? AFAIK, Sikorsky has never even addressed the issue.
The statement that FLRAAi is the selling point for Valor is self-evident. FLRAA is the whole reason for Valor's existence. In fact, it's the whole reason for Defiant's existence as well.
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@irvhh143 As the Army has repeatedly made clear, neither the Valor nor the Defiant that have flown are prototypes. They are Technology Demonstrators, hence the name of their program Joint Multi-Role Technology Demonstrator. Their purpose was to demonstrate their respective advanced technologies and the Army would evaluate the results to decide which concept offers greater potential not only for meeting or exceeding the Army's requirements but also greater potential for achieving its promises. Army only has enough money to operationally develop one of them for the FLRAA (there are actually two "A"s in the program name) program. The next step involves actual prototype(s). Of course the seller is talking about expected performance. That's wast everyone talks about until you actually build the thing. Both bidders gave their expected performance estimates for production models. That's what was being demonstrated, how likely it was that their concepts could achieve their promises. On that basis, Valor clearly demonstrated more and inspired more confidence than Defiant. I wouldn't be surprised if that was the pivotal factor in the decision.
What is your basis that a production Valor cannot take off vertically at operational weight? Even Sikorsky has never claimed that! Regarding hover capability, I would estimate that it could hover for as long as required. Not as efficiently as a regular helicopter, but Bell has always acknowledged that. However, it should hover for as long as the Army has specified (otherwise it would have been rejected). For one thing, it is required to HOGE at mission weight at 6000'/95°, which strikes me as somewhat more than "limited" hover capability. Is the whole aircraft armored like an A-10? No. One good hit on a Chinook's driveshaft and down she goes. All aircraft are vulnerable to enough hits in the right place a the right time. That's just the cost of doing business. But I would opine an aircraft doing 250 kn is less likely to be hit than one traveling at 125. Your objection to FLRAA is an objection to the UH-60, UH-1, H-35,H-19, etc. [not to mention CH-47 and H-53], or any transport helo. What is your alternative? Have the troops walk or ride in trucks? Last time I checked, no helo in flight has been knocked out by an underground mine or IED.
One other thing about FLRAA. Personally, I am not sure that as things stands neither a production Valor or Defaint can meet their original range estimate. The reason is that Army told both contractors to base their production aircraft estimates on the Army delivering the advanced FATE engine. It's become apparent in the past year or so that Army will not be able to deliver that engine to meet the FLRAA schedule, so the contractors were told that for the production aircraft they should select a more current techcnology engine. If the engine(s) chosen turn b out to be heavier or burn more fuel than what Army promised for FATE, the designs are going to take a hit there and Army won't be able to hold them to their original estimates. For the record, the exact same thing happened to Osprey
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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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