DARPA’s new X-76 (darpa.mil)

205 points by newer_vienna 19 hours ago

mrDmrTmrJ 17 hours ago

To be clear, this is not a power-point program but a continuation of a long-standing design work with Bell.

Two articles that cover this in depth are: 1. Revised Fold-Away Rotor Aircraft Concepts Emerge From Special Operations X-Plane Program. December 2024: https://www.twz.com/air/revised-fold-away-rotor-aircraft-con...

2. Bell’s Plan To Finally Realize A Rotorcraft That Flies Like A Jet But Hovers Like A Helicopter. September 2021: https://www.twz.com/41997/bells-plan-to-finally-realize-a-ro...

The second article covers decades of prior wind tunnel testing on the folding rotor concept.

trhway 13 hours ago

> continuation of a long-standing design work with Bell.

sunk investment. The success - it made into production in meaningful numbers - of V-22 means that design will be beaten to death.

Even though Bell X-22 (https://www.youtube.com/watch?v=lFdV5CVXGGw) was much better as prop VTOL than V-22, and for jet VTOL Ryan XV-5 Vertifan (look how great it is flying https://www.youtube.com/watch?v=HwvkjFIYWR8 ) was much better than F-35 has been and X-76 will be.

And giving pilotless future of combat air, a tail sitter https://en.wikipedia.org/wiki/Tail-sitter will work great in pilotless version not needing all that folding/tilting hardware. A pilotless would also not have to have at least double engines/etc for reliability (and the monstrosity of interconnect between those 2 engines like V-22 has and X-76 is bound to have).

moralestapia 16 hours ago

>decades of prior wind tunnel testing on the folding rotor concept

Oof, I wish I had a job like that.

trhway 11 hours ago

join an enterprise software BigCo.

username223 8 hours ago

> Oof, I wish I had a job like that.

Focus on something and become one of the best in the world at it. Expertise pays.

dmbche 16 hours ago

rootusrootus 14 hours ago

The Osprey has a reputation, for sure, but it's mid-pack. They called the F-104 the widow maker for a reason, for example. And the F-16 has a fairly high accident rate, too, slightly higher than the Osprey. Though I think the F-16's history is a bit more lopsided, they made some changes after early production airframes proved pretty accident prone.

hyperific 11 hours ago

Maybe the Osprey's reputation is due not only to the accident rate but also to the fatality rate. A fatal accident in a standard F-16 (not the 2 seater), assuming no one outside the plane is killed, means 1 death. A fatal accident in a V-22 with the same assumptions would have a minimum of 2 deaths (pilot and copilot) at a soft maximum of 26 deaths (2 crew + 24 passengers, possibly more if overloaded).

remarkEon 8 hours ago

nstj 10 hours ago

> The Starfighter had a poor safety record, especially in Luftwaffe service. The Germans lost 292 of 916 aircraft and 116 pilots from 1961 to 1989, leading the German public to dub it Witwenmacher ("widowmaker").[0]

[0]: https://en.wikipedia.org/wiki/Lockheed_F-104_Starfighter

sedatk 13 hours ago

In Turkey, F-104 was called “flying coffin”.

conorbergin 14 hours ago

The Osprey's accident rate is not that bad, and the US Army have ordered a new smaller tiltrotor, the v280.

owlninja 14 hours ago

They officially named it recently to the 'MV-75'.

remarkEon 8 hours ago

burnt-resistor 13 hours ago

L PRGB CHIP BURN

Any time there are planetaries or splines attached to jet engines, it's a really weak spot. This holds for ordinary turboprops too.

GorbachevyChase 9 hours ago

I was wondering why we’ve already give up on the harrier.

aksss 8 hours ago

Well, it's a jet from the 60's, can only scrape mach 1 on the downhill, is in a CAS role, primarily. Cool jet, but it's old tech.

laughing_man 8 hours ago

The Harrier is obsolete.

burnt-resistor 4 hours ago

It was deafening too many pilots and Boeing, Lockheed, and Northrop needed more money. /s

The F-35B can also do Mach 1.6 and the stealth thing.

Some country should give that Pepsi contest winner a demil Harrier in lieu of Frontier Airline miles. https://en.wikipedia.org/wiki/Leonard_v._Pepsico%2C_Inc.

yabones 15 hours ago

The next generations of accidents are going to be even more looney-tunes in nature.

PowerElectronix 18 hours ago

It looks like a maintenance nightmare with those clutches to decouple the blades and the mechanisms to have them folded during cruising. Does it even improve substantially in anh metric over the V280 to put money into it?

carabiner 14 hours ago

All military aircraft are maintenance nightmares. They're also extraordinarily loud and devour fuel. These are not intended to entire commercial service where they need to turn a profit for the operators.

jjk166 13 hours ago

Maintenance is an issue for more than just profitability. More maintenance means fewer sorties in a given time period, heavier reliance on and utilization of supply chains, and fewer platforms that can be serviced by a given set of mechanics and facilities.

Just look at WW2: Germany had some fantastic equipment, but they couldn't field it because they didn't have the fuel, spare parts and the maintenance capabilities available. A tiger could kill 10 Shermans, but the Americans could always bring up an 11th Sherman.

For decades we have been able to afford complacency - we strike when we're ready against people who mostly can't strike back. We can afford to be wasteful because we have so much more than anyone we would go up against. No one is seriously threatening our ability to keep our military going. But militaries need to be prepared for peer conflicts where someone could give us a run for our money.

KaiserPro 13 hours ago

greedo 13 hours ago

jcgrillo 13 hours ago

The F-35s train over my house. When the business end of the engine points downward it rattles the windows and sounds like freedom.

dylan604 12 hours ago

giancarlostoro 14 hours ago

> They're also extraordinarily loud and devour fuel.

Steal helicopters have entered the chat.

greedo 13 hours ago

cucumber3732842 18 hours ago

The V280 is designed to be cheap (a very relative term here).

Reading between the lines, I suspect "fast, but also expensive" was a design option that popped up and was not chosen earlier in the V280 program and now Darpa wants to pay to see where it goes.

Zigurd 17 hours ago

Hard to be more expensive than F-35B.

XorNot 15 hours ago

roysting 10 hours ago

The Congressional Country Club doesn't pay for itself, bud.

rluna828 17 hours ago

it also has stealth. This is a complete disaster. The only purpose of this stealth ship is to steal leaders and or go inside cave lairs and blow them up.

budman1 13 hours ago

without stealth, an aircraft will survive about 5 minutes in contested airspace.

lazzurs 3 hours ago

All these comments and not one single reference to Airwolf.

https://en.wikipedia.org/wiki/Airwolf

meroes 8 hours ago

Why? We just kill everything nowadays with missiles, bombs, and rockets-- heads of government, terrorist leaders, schools... so why are we investing in anything like this?

Seems like some kind of GI Joe fantasy that's gone on for too long.

gorgoiler 5 hours ago

From recent events, operations like the Maduro extraction could always benefit from technology in the category “helicopter, but faster”.

porphyra 18 hours ago

Cool, I guess this should be able to hover in much more "austere" environments than the F-35B STOVL and the Harrier Jet. Tiltrotor with folding rotor blades sounds very mechanically complex and challenging though.

rozab 14 hours ago

It's cool they actually still commission concept paintings like this

smlacy 13 hours ago

That background looks like AI for sure though?

ceejayoz 18 hours ago

So it's an Osprey with a jet in the back?

torginus 18 hours ago

Usually with these programs, they just commission an artist with some vague description, like they tell him to draw a futuristic VTOL aircraft, these pics have zero bearing on what gets delivered.

Sometimes they even take the piss with this, like in this video for a next-gen engine, where you can see their engine doesn't even fit in their fantasy aircraft:

https://www.youtube.com/watch?v=vCHun6rxQm0

dylan604 12 hours ago

That's got to be one of the most comically bad compositing I've seen in a while. I can't believe someone said, looks good, ship it.

brk 15 hours ago

I don't understand the purpose of the Xenon taillight.

reactordev 12 hours ago

“Where we’re going, we don’t need roads”.

The Osprey is amazing, can’t wait to see what the X-76 can do.

kuprel 17 hours ago

From the image it doesn't look balanced for VTOL when the propellors are vertical. Also are the jets enabled during VTOL?

gorkish 15 hours ago

I'm betting the person who created the "artist rendering" isnt an aeronautical engineer.

doublerabbit 15 hours ago

Wager $10 it's a LLM prompt.

0xWTF 14 hours ago

So ... we're going to try even harder to put humans in harm's way?

mikkupikku 16 hours ago

Why won't they adopt one of Sikorsky's compound helicopters already? They're beautiful and elegant solutions to this problem.

cpgxiii 15 hours ago

Because Sikorski can't make them work. Sure, they can take off and fly fast in a straight line, but they haven't been able to demonstrate sufficient maneuverability due to vibration problems in the rotor head. They are also very tall, prohibitively so for existing shipboard hangar, which would otherwise seem to be their advantage over tiltrotor platforms.

bilsbie 17 hours ago

So it has jet engines that blades unfold and attach to during takeoff and landing? Why not always use the blades?

KaiserPro 13 hours ago

Speed and efficiency I suspect

Targeting a propeller for both raw lifting capacity as well as speed is quite difficult. I suspect they have different geometry as well.

If you spin a propeller fast enough the tips break the speed of sound, from what I recall that knackers the efficency. To generate lots of lift a bigger rotor is more efficient (hence why helicopters have long rotoblades that don't spin at high RPM)

The longer the blades the faster the tips, which means there is a tradeoff between thrust and speed of the air being yeeted out the back

numpad0 9 hours ago

My armchair general understanding: airspeed at blade tip can't be supersonic all the time, and that caps the max forward speed for prop driven aircraft. Same don't apply to jet engines with air intakes that can restrict and slow air flow

rluna828 17 hours ago

stealth

bilsbie 17 hours ago

I’d go for simplicity and do a tail lander.

usrusr 14 hours ago

These days my vote would go to a quad. Impeller fore, impeller aft and one in each wing. Behind doors, obviously, like the bays for retractable landing gear - this is a solved problem.

They don't have to be efficient, because how much hovering time would you really need? Battery could even exist only in mission specific pods (internal perhaps, when it's a cargo carrier), trade-off as needed.

KaiserPro 13 hours ago

> They don't have to be efficient

Thats the point, the more efficient the less supply line you need, which means more autonomy.

I cant find the source but in Afghanistan a large proportion of the Allied casualties were from protecting supply lines.

The thing about quad copters is that they work at small scale because the rotor have almost no inertia. When you scale that up to 2m, then inertia is a bitch. That means you need tilting blades to make up for that lack of control.

BUT

You also need something to be powerful enough to alter the speed of the rotors to get yaw.

Plus you then also need to get them all to rotate so that you can get the efficiency of normal flight.

The reason why the osprey exists is because it has longer range than a helicopter (~1200 miles vs 400) its also faster.

usrusr 11 hours ago

bilsbie 13 hours ago

Electric motors are very light too.

dash2 18 hours ago

“ With SPRINT, we're not just building an X-plane; we're building options”. Found the guy who couldn’t be bothered to write his own press release…

newer_vienna 17 hours ago

I'm quite fond of the caption, which describes a "a proof-of-concept technology demonstrator that aims to demonstrate technologies and concepts"

NitpickLawyer 17 hours ago

Brought to you by the Department of Redundancy Department.

irl_zebra 18 hours ago

I think I'd rather have them working on airplane tech rather than writing airplane tech press releases. With this approach, it's not just a tactical thing; it's relieving the burden of wordsmithing from technical people.

bigfishrunning 17 hours ago

The technical people were never wordsmithing, they just didn't hire a technical writer. Instead of freeing up someone to do more design work, it freed someone to interview for a new job. I hope they get it.

palmotea 15 hours ago

binkHN 16 hours ago

jdiez17 17 hours ago

You're absolutely right.

notahacker 18 hours ago

Good to hear that the DoD's new contract with OpenAI is solving all the most important problems...

O5vYtytb 18 hours ago

It's a quote from someone...?

jdiez17 18 hours ago

... who probably wrote their prepared PR statement with an LLM.

esseph 18 hours ago

bigyabai 18 hours ago

It feels like DARPA has fallen so far. In a post-Salt Typhoon era it's really hard to imagine them as dynamic, best-in-class innovators anymore.

ambicapter 17 hours ago

This administration doesn't really prioritize anything that has to do with intelligence, so advanced research was obviously going to fall by the wayside.

browsingonly 14 hours ago

idontwantthis 18 hours ago

Isn't this need already met by the Bell V280 that the army already selected for it's Blackhawk replacement? What is the big innovation they are going for here?

Tuna-Fish 17 hours ago

+50% top speed over the V280. Bell offered it as an alternative to the V280 in the early stage of the contract, but it was judged too experimental (and probably too expensive). Apparently DARPA is funding further development of the concept.

aussieguy1234 9 hours ago

What's the difference between this and standard VTOL?

einpoklum 12 hours ago

And the US will use it to invade your country and kidnap your president if s/he doesn't do what Uncle Sam tells him to.

ocdtrekkie 16 hours ago

I'm confident with the stellar service and safety record of the V-22 that an even more complex tiltrotor will be a standout success for the military.

cpgxiii 15 hours ago

If you look at the V-22 safety record in the context of the level of technical development, it is pretty good (e.g. compare to helicopters and aircraft from the 60s). The first production generation of a brand new type of vehicle is always going to be complicated, and virtually all of the V-22 mishaps come from the "new" components and procedures.

The fundamental tradeoff with tiltrotor platforms is that you trade significantly increased speed for significantly increased complexity. What that means is your battlefield survivability goes up when dealing with any opponent with meaningful air defenses, but at the cost of increasing your "resting" accident rate when most peacetime accidents are consequences of maintenance and/or procedural issues.

laughing_man 8 hours ago

The V-22's safety record is somewhere between a fixed wing aircraft and a helicopter. About what you'd expect.

greedo 13 hours ago

Flying military aircraft is inherently dangerous. The US Army had 15 Class A mishaps in 2025, the USN 12, the USAF 14, and 6 for the USMC. The Apache (AH-64) led the Army, and this is a mature airframe, but shit happens.

wartywhoa23 16 hours ago

16 hull losses per ~400 units built is not exactly a stellar safety record.

Or I guess you mean /stellar?

jdkee 15 hours ago

He is being sarcastic.

tamimio 15 hours ago

I think the blades are added there for deception, most likely it won’t have blades.

EA 14 hours ago

It will need blades to VTOL.

tamimio 14 hours ago

They do exist, WIP, a bladless VTOL

https://newatlas.com/aircraft/jetoptera-bladeless-hsvtol/

> Jetoptera is developing VTOL (Vertical Take-Off and Landing) aircraft that use a "Fluidic Propulsion System" (FPS) instead of traditional rotors or propellers, acting like "bladeless fans on steroids". These systems use compressed air and the Coanda effect to generate high-speed thrust, promising quieter, more efficient, and faster flight (up to Mach 0.8) for aerial mobility.

bigyabai 14 hours ago

Running exclusively off jet power would require an extremely (impossibly?) strong compressor stage coupled a powerful APU to generate lift. It's definitely not light enough to take off without tiltrotors.

tamimio 14 hours ago

The concept is the compressed air sent through slits in a thruster, creating negative pressure that draws in surrounding air, resulting in increased thrust, there’s a concept already of this, check the above reply.

bigyabai 14 hours ago

crimsoneer 17 hours ago

Someone has played the new Deus Ex games

phplovesong 17 hours ago

The swedish gripen can do mach2 (2300km/h) and does not need a traditional runway (500 meters of something "flat enough" will do). I assume its way cheaper than something like this.

gorgoiler 5 hours ago

That doctrine works great for defending your homeland, when you are taking off from your roadside base and coming back home to a road-based airfield already on the map.

My understanding of these VTOL aircraft is they need to travel a long way, quickly, and set down in far less predictable conditions.

phplovesong 2 hours ago

Are you saying these are for human transport? Sounds like real niche in modern warfare.

Zigurd 17 hours ago

I suppose the argument is that X-76 could work in environments without roads. But that also implies without fuel or any other support on the ground.

RandallBrown 17 hours ago

Can it hover?

greatgib 17 hours ago

I can't access darpa.mil. Was it slashdotted because of the article being posted here, or now it is unavailable outside of US?

rcMgD2BwE72F 15 hours ago

Inaccessible from France. With family.dns.mullvad.net private DNS.

logotype 17 hours ago

I can access it from the UK

newer_vienna 17 hours ago

Still up here in the US

HumblyTossed 17 hours ago

Hmmm... that just looks like problems. It's a lot of mechanical parts that always have to work correctly.

dang 16 hours ago

"Please don't post shallow dismissals, especially of other people's work. A good critical comment teaches us something."

https://news.ycombinator.com/newsguidelines.html

01100011 17 hours ago

The Osprey killed a lot of Marines over the past decades. It took a while to work out the issues. Hopefully we will remember what the Osprey taught us.

rluna828 17 hours ago

I wonder is Iran would have gone different if we had captured the Ayatollah instead of killing him. A stealth drop ship like this would have allowed that to happen. The reason why regimes are more likely to negotiate when you capture their leaders is because you might release them. (not a good day for the usurper.)

ivell 16 hours ago

I don't think whatever is negotiated with Iran's current regime would actually be honored by them. They may commit something to get their leader back, but won't be keeping the promises.

Their self stated goal is destruction of Israel and US. They could have chosen peace and not have funded proxies across the middle east. Their choice of aggression by whatever means they have at their disposal just shows what their long term strategy would be.

They have shown the intend. They just didn't have the capacity to follow through. Once they gain the capacity, they could go extreme lengths. Just see how they attacked their neighbors who were not party to the war.

jrapdx3 15 hours ago

A very good response to the parent comment and summary of the current situation.

AIUI the Iranian attack on Arab countries is strategic, increasing energy costs pressures the US to stop military action. However the US and allies were prepared with set aside oil reserves, increasing supplies from other sources, and reducing Iran's ability to interfere with shipping.

Major warfare always has tragic effects, but against regimes actively pursuing destruction of other nations, return of fire is a rational response.

otabdeveloper4 15 hours ago

> A stealth drop ship like this would have allowed that to happen.

Yeah, I saw that Agents of S.H.I.E.L.D. episode too.

Sadly, we might need some more intensive vibranium research before it becomes reality.

sandworm101 16 hours ago

Different engines for different phases of flight? It has been tried many times and never really works. Such craft can be made to fly, but never well. The answer has to come from using one set to power all phases.

Id be interested in seeing a turboprop that can transition to a turbofan/jet once the prop is folded away. The f-35 was a step in this direction.

trelliumD 17 hours ago

that already exists in the form of Saab Gripen :)

FrankBooth 17 hours ago

Where do the 14 soldiers sit in the Gripen?

rkomorn 17 hours ago

On the wings, obviously, for quick deployment. Maybe I mean early deployment.

adolph 15 hours ago

radicalethics 17 hours ago

I wonder what the motivation behind this is. Tactically, why ever show your latest weapon? What is the strategic purpose of this? It's like if I message my opponent in SC2 and tell them exactly what I'm going to tech to. That's ... insane right? Why would anyone do that?

bityard 16 hours ago

This isn't a new weapon, this is a test platform for various ideas, none of which are new or secret. Also, there are not many groundbreaking advancements left in military aviation. Most are just fairly incremental engineering or manufacturing improvements. (Military space technology might be a different story, though.)

The only other nation with the potential to develop a high-tech military plane that could rival US technology would be China. But if we ever got into a war with China, they wouldn't need superior technology to win. They could win via superior manufacturing capacity and the sheer number of people they can draft into service at a moment's notice.

logicchains 15 hours ago

>They could win via superior manufacturing capacity and the sheer number of people they can draft into service at a moment's notice.

Even with their manufacturing capacity they don't have remotely enough boats to get a nontrivial fraction of those people to the US mainland, and the majority of those people can't swim, so they wouldn't help in taking the US mainland, a requirement to "win" a serious war. Their entire armed forces is also almost completely lacking in combat experience, and in their last skirmish (against some unarmed Indian soldiers in the mountains) 30+ soldiers Chinese tragically drowned, due to the aforementioned lack of swimming ability.

wewtyflakes 14 hours ago

foobarian 16 hours ago

They could just cease all shipping. The consequences would be legendary.

jiggawatts 12 hours ago

benjcpalm 17 hours ago

It's not a tactical choice- it's strategic deterrence, and it's not insane at all!

The US has always had a policy of messaging programs, with a lean toward classifying some percentage of the specific capabilities.

There's a reason that F-35 program was publicized by the US government as the program was under development. It makes the US air force even scarier, which discourages adversaries from thinking about conventional warfare with America.

That said- you won't see any detailed pics of the inside of an F35 cockpit, or a detailed look at the heads up display in the fancy helmet. That's top secret, because those making those details public don't offer enough additional deterrence to justify the risk to the program.

bityard 16 hours ago

Yes, but even if the US didn't release the specifications of the F35, other countries around the world would rapidly figure out most of the capabilities anyway from photos, videos, and casual observation. (In other words, they'd know soon enough WHAT it can do but not necessarily HOW it does it.)

Alan_Writer 16 hours ago

I think they just show what it can be seen, like any country with advance military developments.

They won't show you everything.

Have you ever heard about those sound/sonic (or something similar) weapons the US used in Maduro's kidnap operation? Venezuelan soldiers said (pero some publications on the internet) that they never saw anything alike, leaving them completely disoriented and helpless?

Soldiers now can even see thermal figures through walls or solid materiales, and the same time, bacome invisibles.

It's more than sci-fi.

laughing_man 8 hours ago

Normally these kinds of press releases come out to generate public support for funding. I remember when the B-2 was super, super secret. No photos, "we don't know what you're talking about" answers from the military.

But when it looked like it might get cancelled pictures and exhibitions of it were suddenly everywhere.