Sikorsky-Boeing SB-1 Defiant

Looks like we are at BERP IV iteration. I had no idea about this development. I wonder what kind of tip they use for these new compounds. The blackhawk has the simple swept tip.

https://www.flightglobal.com/berp-iv-gi ... 52.article

https://dspace-erf.nlr.nl/xmlui/bitstre ... sequence=1

https://www.semanticscholar.org/paper/B ... c9adc?p2df

Looks like we are at BERP IV iteration. I had no idea about this development. I wonder what kind of tip they use for these new compounds. The blackhawk has the simple swept tip.

HH-60W has the same growth rotor blades found on the S-92. Same anhedral.

Defiant-X: Sikorsky, Boeing Unveil FLRAA Design

The companies’ proposed Future Long-Range Assault Aircraft (FLRAA) to replace the UH-60 is a sleeker, stealthier version of the prototype SB>1 Defiant now in flight tests. Can it beat Bell’s tiltrotor?

WASHINGTON: Sikorsky and Boeing did “hundreds of trade studies” and consulted extensively with the Army to refine their SB>1 Defiant compound helicopter into the new Defiant-X, officially unveiled today.



What’s the difference? The companies were cagey about details, and they said they may make further tweaks. But between their guarded statements and the keen eyes of fellow reporters on the conference call, we can highlight a few visible changes in the images released today:

Defiant-X has beefed up landing gear, having gained a nose wheel that the SB>1 Defiant lacked. (SB>1 had two large wheels forward and a small wheel on the tail – check out these close-ups). This almost certainly adds weight, but, the companies said, it will improve stability on rugged frontline landing zones.

Defiant-X gets rid of the prominent exhaust outlet that SB>1 had below its engine. That helps “reduce thermal signature,” the companies said in a statement. In other words, the new design sheds its engine heat in a different and less detectable way, making it stealthier against enemy infrared sensors and harder to target. The companies said they’re still deciding which specific engine to install. They’ll have to find the best balance of raw power, ease of maintenance, and heat.

Finally, Defiant-X has a more sharply angled nosecone and a pronounced ridge on the back half of the fuselage. Such “mold line” changes improve the aircraft’s “aerodynamic handling,” the companies said. There’s no word on whether they also improve its speed, a high priority for the Army – and an area where the SB>1 has lagged its rival, the Bell V-280 Valor...

https://breakingdefense.com/2021/01/def ... aa-design/

A strong side wind is going to blow that sucker over on its side. Remember, you heard it here first.

Tail strikes will never be a problem, I'm sure.

FWIW,

Interesting datum to consider when analyzing their claims: According to Flight Global, since its delayed first flight in March of 2019, they've only flown the SB>1 31 times with a total flight time of 26 hours.

Seems like tall helicopters will be a real bitch to maintain in the field. Neither Defiant nor V-280 impress me as sustainable.

A strong side wind is going to blow that sucker over on its side. Remember, you heard it here first.

Yep, I read about Chinock's being blown over all the time...

Ever heard of the aerodynamic design philosophy " if it looks right it usually is right?"

That thing does not look right. It looks too tall for its landing gear width.

If you are more comfortable with technical terms, it looks "tipsy."

Chinook's are wide and squat by comparison, with a wheel on each corner like a go cart.

I do not believe you when you say you hear of Chinooks blowing over all the time.

That is just "fake news."

Do not believe it.

Earlier this month the Sikorsky went a little bit faster than previously tested. While still behind what Bell's tilt rotor design has demonstrated the Sikorsky design seems to be gradually hitting its stride...

https://www.flightglobal.com/helicopter ... 95.article

The Sikorsky-Boeing joint team behind the SB-1 Defiant, a co-axial helicopter with a pusher propeller, believes the rotorcraft demonstrator can go slightly faster.
***
The SB-1 Defiant has hit a top speed of 247kt (457km/h) while flying level in a test, but Bill Fell, FLRAA principal test pilot, says he believes the aircraft can go even faster.

“Even when we went 247kt, we had engine power available,” he says.

Fell declines to say specifically how much faster he thinks the SB-1 can fly. “I think anything above 250[kt] is going to put a smile on my face when I get home,” he says.

The proposed Defiant X is designed to be able to fly at 230kt in cruise, which is the US Army’s requirement for FLRAA. Speeds near or above 250kt would be considered a dash speed.

Bell’s V-280 demonstrator has reached 300kt in flight testing. Because the tiltrotor can fly horizontal on its wing it is more efficient and fast in cruise mode.

Against that speed, the Sikorsky-Boeing team has argued that the Defiant X would more manoeuvrable during its final approach to the landing zone. For example, the helicopter can reverse its propeller and go from 200kt to a hover in about 800m (2,640ft), says Fell.

SB-1 is such an impressive aircraft but when it comes to dealing with China nothing is going to do it better than V-280. Range, payload and speed will be incredibly good, it'll tip the scales towards survival and operation success much more often, IMO. I hope Pentagon and Congress get both, but a lot more V-280 is the game-changer if there can only be one.

SB-1 is such an impressive aircraft but when it comes to dealing with China nothing is going to do it better than V-280. Range, payload and speed will be incredibly good, it'll tip the scales towards survival and operation success much more often, IMO. I hope Pentagon and Congress get both, but a lot more V-280 is the game-changer if there can only be one.

Assuming both meet their promises and the Army requirements (and if one doesn't than the decision is made right there). Buying both would mean procuring two different aircraft when one will do. You'd have separate procurement actions, two EMDs, two different logistics pipelines, two separate training pathways, etc. Army doesn't want to spend that kind of money even if they had it, which they don't, which would mean something else they need couldn't be funded.That'd be like USAF buying both the F-22 and F-23 or both the F-16 and the F-17.

https://theaviationgeekclub.com/defiant ... dings/amp/

The Lockheed Martin Sikorsky-Boeing SB>1 Defiant successfully completed Future Long-Range Assault Aircraft (FLRAA) mission profile test flights, including confined area landings and low-level flight operations. These flights validate Defiant’s relevancy to the Army’s mission, providing agility at the objective (also known as the “X”), and increased survivability, all while reducing pilot workload.
***
Air assault is the movement of ground-based military forces by vertical take-off and landing (VTOL) aircraft—such as the helicopter—to seize and hold key terrain which has not been fully secured, and to directly engage enemy forces behind enemy lines. In addition to regular infantry training, air-assault units usually receive training in rappelling, fast-rope techniques and air transportation, and their equipment is sometimes designed or field-modified to allow better transportation within aircraft.

The US Army field manual FM 1-02 (FM 101-5-1) describes an “air assault operation” as an operation in which assault forces (combat, combat support, and combat service support), using the firepower, mobility, and total integration of helicopter assets, maneuver on the battlefield under the control of the ground or air maneuver commander to engage and destroy enemy forces or to seize and hold key terrain usually behind enemy lines.

I am not air assault qualed but I've seen plenty of demos and training exercises. The one thing that I noticef between V-22 and Black Hawks conducting fast rope is how quickly the Black Hawk can decelerate and manuever in position when compared to the Osprey.

IF the SB-1 demonstrated this as good as stated, it could fit the US Army's mission profile better than the V-280 even though in pure performance and range the V-280 is a better option.

https://theaviationgeekclub.com/defiant-executes-us-army-air-assault-mission-profile-demonstrates-unsurpassed-speed-maneuverability-and-agility-in-high-speed-low-level-operations-and-confined-area-landings/amp/

The Lockheed Martin Sikorsky-Boeing SB>1 Defiant successfully completed Future Long-Range Assault Aircraft (FLRAA) mission profile test flights, including confined area landings and low-level flight operations. These flights validate Defiant’s relevancy to the Army’s mission, providing agility at the objective (also known as the “X”), and increased survivability, all while reducing pilot workload.
***
Air assault is the movement of ground-based military forces by vertical take-off and landing (VTOL) aircraft—such as the helicopter—to seize and hold key terrain which has not been fully secured, and to directly engage enemy forces behind enemy lines. In addition to regular infantry training, air-assault units usually receive training in rappelling, fast-rope techniques and air transportation, and their equipment is sometimes designed or field-modified to allow better transportation within aircraft.

The US Army field manual FM 1-02 (FM 101-5-1) describes an “air assault operation” as an operation in which assault forces (combat, combat support, and combat service support), using the firepower, mobility, and total integration of helicopter assets, maneuver on the battlefield under the control of the ground or air maneuver commander to engage and destroy enemy forces or to seize and hold key terrain usually behind enemy lines.

I am not air assault qualed but I've seen plenty of demos and training exercises. The one thing that I noticef between V-22 and Black Hawks conducting fast rope is how quickly the Black Hawk can decelerate and manuever in position when compared to the Osprey.

IF the SB-1 demonstrated this as good as stated, it could fit the US Army's mission profile better than the V-280 even though in pure performance and range the V-280 is a better option.

I'm sorry, but I don't believe your V-22/Black Hawk comparison is valid. They are designed for similar but different missions. A better comparison would be against the CH-46 or -47 which are the type of craft the V-22 was designed to replace, and neither of those choppers are as agile as the UH-60.

Regarding SB>1. it's worthy of note that the video shows it demonstrating its "low speed" agility with a significant amount of forward speed, which enhances the ability of any aircraft to perform maneuvers including providing aerodynamic lift. The V-280 years ago demonstrated high agility at extremely low speeds and in the hover (probably better overall than the UH-60 itself), something the SB>1 has yet to do. I'm also waiting to see their touted unprecedented deceleration in level flight to the hover for assault landings. I note that in this demonstration they did not shut down the prop like they say they can do in confined spaces and will be required on the ground to permit 360° egress/ingress.

Regarding fast rope, the Valor has already performed fast rope demonstrations with real, live fast roping people. AFAIK, the Defiant has yet to attempt this. Given when selection is supposed to be, time is running out.

No one should be surprised by this:

https://www.flightglobal.com/helicopter ... 08.article