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V-280 wins US ARMY FLRAA contract

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V-280 wins US ARMY FLRAA contract

Old 28th Apr 2023, 12:02
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Originally Posted by Commando Cody
Max. allowable weight for FARA has been specified by Army.

Regarding power requirements, I don't know about Sikorsky, but Bell publicly stated where their power requirement came from. For FLRAA Army had stringent Hot and High HOGE requirements. For Bell that drove the required power for Valor. With that kind of power, the speed expectation came out at 280 knots, hence the name. As it turned out V-280 was able to go 25 knots faster than that. Sikorsky may have determined Defiant-X's power requirements the same way.

Your calculations may very well be spot on. If Raider-X turns out slower, I don't think it can win except on industrial policy grounds. Aside from how far behind Army schedule it would put Sikorsky, since the Army specified one ITEP engine only for main power, Sikorsky really doesn't have an option to go to a twin. Plus, as I stated elsewhere, if Sikorsky was allowed to go to two engines, the whole FARA competition collapses and Army has to start over with a new RFP on which everyone can bid. They're already on slippery grounds with the specs as is.
https://www.defensedaily.com/engine-...ly-fy-26/army/

The Army is currently going through an Analysis of Alternatives that won't be complete for months. Will definitely be interesting to see what alternatives are being analyzed.

The X-2 power demands are more typically set by target max cruise speed and then hover and hover agility is a fall out of that, so the opposite of a tilt rotor. You're right that, in FARA's case, the competitive prototypes were heavily influenced to have a single ITE engine which will cap the max cruise speed of both aircraft. Bell's Invictus get's a little wiggle room with its SPU approach.

If the AoA process determines that a twin best suits the Army's needs, the final proposal requirements will reflect that and both competitive prototypes will feed data into the design of the new, larger FARA... assuming the aircraft fly before important decisions get made on those aircraft. Not sure how the Army will handle protests/lawsuits if the final requirements are substantially different than those of the earlier FARA phase that birthed the competitive prototypes.
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Old 28th Apr 2023, 20:03
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Originally Posted by SplineDrive
https://www.defensedaily.com/engine-...ly-fy-26/army/

The Army is currently going through an Analysis of Alternatives that won't be complete for months. Will definitely be interesting to see what alternatives are being analyzed.

The X-2 power demands are more typically set by target max cruise speed and then hover and hover agility is a fall out of that, so the opposite of a tilt rotor. You're right that, in FARA's case, the competitive prototypes were heavily influenced to have a single ITE engine which will cap the max cruise speed of both aircraft. Bell's Invictus get's a little wiggle room with its SPU approach.

If the AoA process determines that a twin best suits the Army's needs, the final proposal requirements will reflect that and both competitive prototypes will feed data into the design of the new, larger FARA... assuming the aircraft fly before important decisions get made on those aircraft. Not sure how the Army will handle protests/lawsuits if the final requirements are substantially different than those of the earlier FARA phase that birthed the competitive prototypes.
When I was talking how Bell's power requirement was derived I was referring to V-280's because Defiant-X was cited. In the absence of the stringent hot and high requirement I don't know that they'd need that much power

I believe the RFP specifically mandated that designs had to be based on a single ITEP engine. If that hadn't been in there, I doubt that all five FARA contenders would have picked the same propulsion package. The speed requirement was 180 knots with a 200-205 knot dash. RFP also capped maximum weight as ≤14,000 lbs with a 40' rotor. I'm saying that if Army now said, "Weeell, engine selection and how many is now open", that would be such a major change they'd have to go back out and re-solicit since the losers could say they could have designed something different and they would be better than what won. That may or may not be true, but it would be a valid enough claim that it would stop the program.

Last edited by Commando Cody; 29th Apr 2023 at 01:36.
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Old 29th Apr 2023, 06:14
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After Sikorsky's FLRAA debacle (with their submission's lack of architectural detail as articulated by GAO, and the underwhelming performance of their SB>1 Defiant demonstrator) - why don't they concede that X2, whilst being a novel concept, is a dud in practical terms?

With X2, the marginal gain in top speed provided by the pusher prop and coaxial rotors, is insufficient to offset the detriments ... such as increased cost (to start with), together with increased weight, cubic-foot volume / displacement, complexity, and maintenance to flight hour ratio. Which shall likely lead to reduced reliability, operational tempo, and readiness rate.

Given the valid questions raised, about whether Raider-X shall realize a speed advantage of any significance over the Bell 360 Invictus - what's the point of Sikorsky continuing with the design?

With the delay in receipt of the GE T901, they've an opportunity (if they act fast) to start from scratch - and produce an entirely new FARA design.

Perhaps they aren't permitted to do so, by the FARA tender rules - given the Army selected them as one of the two finalists, based upon their originally submitted X2-centric design.
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Old 29th Apr 2023, 12:22
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Accepting Reality

To a slightly lesser degree, Sikorsky and LM management are suffering from the same delusions as EVTOL startup developers “This technology will be viable, if just given time for development, a huge infusion of cash, and one or two technical miracles”.

For the FLRAA program, LM management was betting that Bell would fail badly. This would have left the US Army with the option of either canceling the whole program (and continue buying Blackhawks), or selecting the least bad of two failures. If choosing the second option, selecting the cheapest of the two would have made good sense. Since this would leave the Army more money to buy more Blackhawks. This also explains the ridiculous low ball cost of the LM submission.

For FARA, given the Army’s track record of failures to develop a Kiowa replacement, LM was more interested in getting US Army funding to develop X-2 technology than manufacturing production aircraft. The limited mission and high cost of an X-2 FARA translates to very low production volume.

So in short, LM is in FARA for the development dollars for X-2 technology. Switching to a conventional helicopter configuration robs them of this funding.

Last edited by CTR; 29th Apr 2023 at 12:37.
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Old 29th Apr 2023, 16:40
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Originally Posted by txtworld
Given the valid questions raised, about whether Raider-X shall realize a speed advantage of any significance over the Bell 360 Invictus - what's the point of Sikorsky continuing with the design?

With the delay in receipt of the GE T901, they've an opportunity (if they act fast) to start from scratch - and produce an entirely new FARA design.

Perhaps they aren't permitted to do so, by the FARA tender rules - given the Army selected them as one of the two finalists, based upon their originally submitted X2-centric design.
Raider-X is the last chance to realize some revenue out of the many hundreds of millions of IRAD dollars and years of engineering time expended on X-2 technology. Raider-X is being designed/build on Army money, so it would require the Army's permission to radically change the design and Sikorsky can't move fast enough to build a largely new aircraft even if it wanted to, at this point.

They're stuck building a ship that will be more expensive and heavier than the Bell while barely meeting the performance goals and having to promise that the "full potential of X-2 Technology" will get unlocked with future power pushes of T901 or adding a second T901 while promising that they won't run into scaling issues... again.
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Old 29th Apr 2023, 17:04
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Originally Posted by CTR
To a slightly lesser degree, Sikorsky and LM management are suffering from the same delusions as EVTOL startup developers “This technology will be viable, if just given time for development, a huge infusion of cash, and one or two technical miracles”.

For the FLRAA program, LM management was betting that Bell would fail badly. This would have left the US Army with the option of either canceling the whole program (and continue buying Blackhawks), or selecting the least bad of two failures. If choosing the second option, selecting the cheapest of the two would have made good sense. Since this would leave the Army more money to buy more Blackhawks. This also explains the ridiculous low ball cost of the LM submission.
When Sikorsky teamed with Boeing on SB>1, the Sikorsky troops were told that Boeing examined Bell's proposed tilt rotor and decided it wasn't a good aircraft, Boeing didn't have technology inside the firm to meet FLRAA goals, and that left Sikorsky with the technology Boeing wanted to partner with. Of course, that line was a bunch of BS. Some years later, when V-280 first flew, there were some public congratulations on social media by various Sikorsky engineers. The SB>1 CE called an all-hands meeting and told staff not to give congratulations because Bell's success was a serious threat to Sikorsky. Defiant was badly behind schedule with lots of critical paths holding first flight far into the future.

So I don't know that Sikorsky's leadership really bet on Bell failing badly, but their schedule and flight successes were a shock.

Sikorsky has actually studied tilt rotors quite a bit, though mostly in the context of their variable diameter technology, but the VDTR bits aren't necessary. There must have been some critical meetings in the early 2000's where the future IRAD efforts of the company were aimed. The V-22 was still struggling towards initial operating capability and the 609 was entering flight testing. So tilt rotors were moving from a future threat to a present threat, but one with observable challenges even for the industry leader in the field. Instead of being a second tier OEM for tilt rotor technology, they reached to the XH-59A and decided to be the first tier OEM for a different approach to higher performance. All the problems of the XH-59A were known but only some got solved or improved sufficiently by todays technology (in the end). Would love to have been a fly on the wall during those discussions. The XH-59A had the same general level of technology as the XV-15 but only few a few hundred hours before being retired as opposed to the thousands of hours and decades of flight history of the XV-15. Given the same level of technology, the tilt rotor appears to be a more practical aircraft. Even if today's technology made an X-2 practical, did Sikorsky not imagine that the same level of technology applied to a tilt rotor would make it even more practical? Or did they imagine that Bell would use the 1980's technology of the V-22 and Defiant could leap past it?
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Old 29th Apr 2023, 22:11
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Originally Posted by SplineDrive
When Sikorsky teamed with Boeing on SB>1, the Sikorsky troops were told that Boeing examined Bell's proposed tilt rotor and decided it wasn't a good aircraft, Boeing didn't have technology inside the firm to meet FLRAA goals, and that left Sikorsky with the technology Boeing wanted to partner with. Of course, that line was a bunch of BS……

So I don't know that Sikorsky's leadership really bet on Bell failing badly, but their schedule and flight successes were a shock……….

Both FLRAA teams were Partially funded to build prototypes by the US Army. Sikorsky/Boeing were awarded approximately 15% more than Bell was. The remainder of the funding required was ponied up by the companies as an investment.

Sikorsky and Boeing Defence divisions combined have over one hundred billion dollars in annual revenue. Textron Defense divisions have slightly over four billion dollars.

Sikorsky made a losing bet, that they did they didn’t need to invest more company funds and manpower to beat Bell, and win FLRAA. Both companies had the funds and manpower to perform much better than shown in the demonstration phase.
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Old 29th Apr 2023, 22:12
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Originally Posted by SplineDrive
When Sikorsky teamed with Boeing on SB>1, the Sikorsky troops were told that Boeing examined Bell's proposed tilt rotor and decided it wasn't a good aircraft, Boeing didn't have technology inside the firm to meet FLRAA goals, and that left Sikorsky with the technology Boeing wanted to partner with. Of course, that line was a bunch of BS……

So I don't know that Sikorsky's leadership really bet on Bell failing badly, but their schedule and flight successes were a shock……….

Both FLRAA teams were partially funded to build prototypes by the US Army. Sikorsky/Boeing were awarded approximately 15% more than Bell was. The remainder of the funding required was ponied up by the companies as an investment.

Sikorsky and Boeing Defence divisions combined have over one hundred billion dollars in annual revenue. Textron Defense divisions have slightly over four billion dollars.

Sikorsky made a losing bet, that they didn’t need to invest more company funds and manpower to beat Bell to win FLRAA. Sikorsky and Boeing had the funds and manpower to perform much better than shown in the demonstration phase.
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Old 29th Apr 2023, 22:24
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Originally Posted by SplineDrive
When Sikorsky teamed with Boeing on SB>1, the Sikorsky troops were told that Boeing examined Bell's proposed tilt rotor and decided it wasn't a good aircraft, Boeing didn't have technology inside the firm to meet FLRAA goals, and that left Sikorsky with the technology Boeing wanted to partner with. Of course, that line was a bunch of BS. Some years later, when V-280 first flew, there were some public congratulations on social media by various Sikorsky engineers. The SB>1 CE called an all-hands meeting and told staff not to give congratulations because Bell's success was a serious threat to Sikorsky. Defiant was badly behind schedule with lots of critical paths holding first flight far into the future.

So I don't know that Sikorsky's leadership really bet on Bell failing badly, but their schedule and flight successes were a shock.

Sikorsky has actually studied tilt rotors quite a bit, though mostly in the context of their variable diameter technology, but the VDTR bits aren't necessary. There must have been some critical meetings in the early 2000's where the future IRAD efforts of the company were aimed. The V-22 was still struggling towards initial operating capability and the 609 was entering flight testing. So tilt rotors were moving from a future threat to a present threat, but one with observable challenges even for the industry leader in the field. Instead of being a second tier OEM for tilt rotor technology, they reached to the XH-59A and decided to be the first tier OEM for a different approach to higher performance. All the problems of the XH-59A were known but only some got solved or improved sufficiently by todays technology (in the end). Would love to have been a fly on the wall during those discussions. The XH-59A had the same general level of technology as the XV-15 but only few a few hundred hours before being retired as opposed to the thousands of hours and decades of flight history of the XV-15. Given the same level of technology, the tilt rotor appears to be a more practical aircraft. Even if today's technology made an X-2 practical, did Sikorsky not imagine that the same level of technology applied to a tilt rotor would make it even more practical? Or did they imagine that Bell would use the 1980's technology of the V-22 and Defiant could leap past it?
From what I've been able to determine, when Bell and Boeing talked, the latter wanted too much control, espeecially in the Fkight Control System, and Bell wouldn't agree so Boeing walked (much to Bell's relief).

Regarding the XH-59A, after the initial tests, the Government proposed a shared cost continued program with the craft being converted to an "XH-59B" configuration that involved new advanced rotors, two GE T700s) and a ducted pusher propeller at the tail. Sikorsky refused to share any of the costs and so the plane was grounded. Not a great show of confidence.

Contrast that with the XV-15 where Bell shared the cost of the initial NASA testing and then with supplemental NASA/Army testing. After that phase, NASA was going to ground one of the two XV-15s because it wasn't needed for what further research was planned. Bell stepped forward and leased their XV-15 back from the government and continued flying it at 100% their cost. That's where you saw all those demonstrations, air shows and guest pilot flights. It even went to the Paris Air Show. . That one flew until August of 1992 when while being flown by a guest pilot a bolt slipped out of the collective control system on one pylon and caused a rollover while in hover. The aircraft suffered major damage but the crew only had minor injuries. The other XV-15 flew until September of 2003 when after using up all its rotor life it was flown to the Smithsonian.

Probably more than anyone wanted to know, but it shows there was an advantage even then.

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Old 29th Apr 2023, 22:49
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Originally Posted by Commando Cody
From what I've been able to determine, when Bell and Boeing talked, the latter wanted too much control, espeecially in the Fkight Control System, and Bell wouldn't agree so Boeing walked (much to Bell's relief)…...
Commando Cody, My friends told me the same Boeing departure story. There’s also a follow up story.

After the Boeing FLRAA split, Bell approached Boeing with an offer that they build the fuselage for the V280 as a subcontractor to Bell. Boeing responded that they would only build the fuselage if they were paid to develop the flight control system also. This truly displays the inflated ego Boeing had in dealing with Bell.

Boeing assumed that Bell could not develop an advanced Fly-by-Wire flight control system without their help. But the opposite was true. Bell developed a much better flight control system, by not having any Boeing “help”.

Last edited by CTR; 29th Apr 2023 at 23:05.
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Old 10th May 2023, 23:59
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Nightstalkers future

Interesting piece here talking about half of 160th SoAR Mh-60 and A/MH-6 going to be replaced by high speed platforms come 2030s…

https://www.thedrive.com/the-war-zon...bX2P3RG_lqOZD8

cheees
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Old 12th May 2023, 11:54
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The Army has now started looking into what they want as a future heavy lift helicopter. Defiant could only lift half what the Valor lifted, and Sikorsky's president said X2 technology would not make a good heavy lift helicopter. So the Army has three choices. An upgraded Chinook, but the Army has seemed lukewarm to this idea. A Sikorsky CH-53K, but the CH53 series has never been able to displace the Boeing Chinook. Or a tiltrotor, if the Army wants speed and range. All of the big three will propose a tiltrotor if the Army requirement is for higher speed.
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Old 12th May 2023, 15:37
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Originally Posted by noneofyourbusiness
The Army has now started looking into what they want as a future heavy lift helicopter. Defiant could only lift half what the Valor lifted, and Sikorsky's president said X2 technology would not make a good heavy lift helicopter. So the Army has three choices. An upgraded Chinook, but the Army has seemed lukewarm to this idea. A Sikorsky CH-53K, but the CH53 series has never been able to displace the Boeing Chinook. Or a tiltrotor, if the Army wants speed and range. All of the big three will propose a tiltrotor if the Army requirement is for higher speed.
I don't think it's true that Defiant could only lift half of what Valor can. They have similar installed power and gross weight, but Defiant has lower disk loading (counting the coaxial system as a single disk of 8 blades). It will fundamentally be more efficient at turning engine power into lift in a hover than a tilt rotor with higher disk loading and increased download due to the wing. There are lots of things to criticize X-2 aircraft on, but hover capability isn't one of them. Smoothly flying forward from a hover or yaw authority in a hover, certainly, lol.

In any case, X-2 technology doesn't scale to the heavy lift class because of the rotor loads, structure, and vibrations problems scale faster than the aircraft does. Since Bell's winged Invictus was selected, perhaps the Army is taking another look at lift compounded helicopters. BV-347 tested out lift compounding on the CH-47 platform (along with 4 bladed rotors and increased rotor separation). Combined with the drag clean up work on the BV-360, it's possible that a modern winged tandem could be attractive to the Army. Less top speed than a tilt rotor, but more longitudinal CG control for external lift operations. Still, if the Army wants a heavy lifter to match the range and speed of their V-280's, the tilt rotor configuration will be the baseline to compare to.
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Old 12th May 2023, 17:06
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Defiant only lifted 5300 lbs, Valor 10,000. I agree in theory the Defiant should be able to lift more, but this was never demonstrated. Perhaps transitioning to forward flight with a heavy load is a problem.
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Old 12th May 2023, 18:02
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Originally Posted by noneofyourbusiness
Defiant only lifted 5300 lbs, Valor 10,000. I agree in theory the Defiant should be able to lift more, but this was never demonstrated. Perhaps transitioning to forward flight with a heavy load is a problem.
Do you have a public reference for Valor lifting 10,000 lb?
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Old 12th May 2023, 19:48
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https://www.flightglobal.com/helicop...151927.article
https://en.wikipedia.org/wiki/Bell_V-280_Valor
https://www.inceptivemind.com/bell-v-280-valor-selected-new-u-s-army-long-range-assault-aircraft/28660/

https://ukdefencejournal.org.uk/bell-v-280-valor-tiltrotor-progresses-flight-tests/

"The V-280 will have a crew of 4 and be capable of transporting up to 14 troops. Dual cargo hooks will give it a lift capacity to carry a 10,000 lb M777A2 Howitzer while flying at a speed of 150 knots."
So maybe not demonstrated yet, but most probably can. Yet Sikorsky/Boeing should have demonstrated what should have been their strong point, but never did.


"Sikorsky has said that the X2 design is not suitable for heavy-lift size, and instead suggests the CH-53K for heavy-lift and tiltrotor for the ultra-class."
https://en.wikipedia.org/wiki/Sikors...g_SB-1_Defiant

Last edited by noneofyourbusiness; 12th May 2023 at 20:04. Reason: adding stuff
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Old 12th May 2023, 22:42
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Yes, exactly. The 10,000 lb requirement was a sizing requirement for both aircraft during that phase of development. I'm not disputing that either aircraft was or was not sized to that requirement, just pointing out Bell has not publicly demonstrated that yet with the V-280. There's enough BS and mixing up of facts/FUD on the internet, we don't need to generate more.
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Old 13th May 2023, 12:50
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Bell did perform sling load demos in 2020/2021.

https://www.ainonline.com/aviation-n...es-sling-loads
https://aviationweek.com/shownews/fa...ur%20in%202021.

I just haven't seen the max weight they hauled.

If we just consider Defiant, they did achieve a max level flight speed of 247 knots against the original target of 250 knots, which is pretty impressive. As Defiant achieved a lift of 5300 lbs, that is underwhelming, considering the requirement of 10000 lbs.


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Old 15th May 2023, 00:04
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Originally Posted by noneofyourbusiness
Bell did perform sling load demos in 2020/2021.

https://www.ainonline.com/aviation-n...es-sling-loads
https://aviationweek.com/shownews/fa...ur%20in%202021.

I just haven't seen the max weight they hauled.

If we just consider Defiant, they did achieve a max level flight speed of 247 knots against the original target of 250 knots, which is pretty impressive. As Defiant achieved a lift of 5300 lbs, that is underwhelming, considering the requirement of 10000 lbs.

Of course Bell achieved a max level flight speed of 305 knots against their original target of 280 knots, which is even more impressive. Still, your post raises an interesting question: Why couldn't the Defiant team get just three more knots to achieve their promise? Could it be vibration was so bad that they just couldn't do it? I don't know but I'm curious. It's also interesting to observe that a while back they started trumpeting they had reached 235 knots which, ..."met the Army requirement" and said they were going to concentrate "...where it is more important..." "...at the X.." in the lower speed regime. BTW, the original FLRAA requirement was supposed to be for 250 knots but was lowered in the final RFP. that went out. Note also that S-97 never achieved its promised speed.

Regarding sling load, don't forget these were technology demonstrators, not even prototypes, whose purpose was to demonstrate that their technology was viable and could be counted on in a production version to achieve all FLRAA requirements. Given that, I wouldn't hold it against either of them that they didn't demonstrate all of the FLRAA requirements expected of a fully developed production model. For one thing, they didn't have definitive engines . They were just supposed to demonstrate that it was likely that they would be able to do so after EMD.

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Old 15th May 2023, 13:06
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Commando Cody
Tiltrotor wins on speed and range, which is what the Army wanted. So why did Sikorsky bid what was likely to be a losing design? People rightfully questioned whether the X2 could be scaled up to a larger size. Defiant proved the answer is yes.

You are right regarding engines, the Honeywell engine on Defiant was going to be scaled up to provide 7500 hp each compared to the demonstrator 5000 hp, giving a total of 15000 hp, which would provide more lift. Given larger engines and more time, hitting 260 knots, matching the X2, seems plausible. Though fuel burn rate might be very high.

Raider is intriguing regarding its low max speed, it had plenty of engine. Maybe Boeing or Sikorsky figured out how to solve the problem for Defiant? But I don't see how they would have been able to significantly improve aerodynamics. So maybe improving vibration control was the solution?

Last edited by noneofyourbusiness; 15th May 2023 at 13:34.
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