DARPA’s new X-76
darpa.mil
darpa.mil
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.
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.
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).
https://en.wikipedia.org/wiki/Accidents_and_incidents_involv...
Sure, its going to take decades to actually make the transition and the UH-60 will remain in service for decades more after that in less demanding roles. I expect by the time this finishes, the MV-75 will be considered another workhorse, if maybe slightly fuzzier and the UH will be an antiquated platform.
But ultimately they both solve the same problem, moving stuff from A to B in rough terrain fast. But with the ever increasing amount of reconnaissance assets, A needs to be further behind the frontline and so range and speed needs to increase beyond what you can manage with a pure helicopter.
The key requirements that drive MV-75's downsides (size, complexity, cost) is the Army wants to play game in the Pacific. The UH-60 is deeply limited there.
For example, the MV-75's range should let it go (one-way) from Guam to the Philippines, straight from Okinawa to Taiwan (no need to island hop) - potentially as a two way mission. Same as Philippines to Taiwan.
The "comparability" is that the MV-75 and UH-60 can be delivery ~14 troops into an order magnitude similar size clearing.
[0]: https://en.wikipedia.org/wiki/Lockheed_F-104_Starfighter
Other european airforces using them were more lucky, IIRC.
That aside, they could be seen as the exported rests of the bargain-basement of the MIC of the USA, when the USAF/Navy already had better options(seen as a whole weapon-system, not a few speed/climb/altitude records(for the initial, only lightly loaded version) which won't matter in real combat).
Any time there are planetaries or splines attached to jet engines, it's a really weak spot. This holds for ordinary turboprops too.
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.
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.
I wonder if the flight hour cost of F 35 includes the maintenance it's undergoing when it's not available.
Putting aside the export market, it's a small miracle that the F-35 turned out as well as it did. Having a mostly-common fighter airframe shared between the Navy, Marines and Air Force was a pipe dream in the 90s. America is lucky the program didn't collapse entirely.
Wildly dependent on your definition of "modern", which mostly depends on your potential adversary. The Russia/Ukraine, and the new war in the Gulf have shown numerous ways in which 4th generation jets, and more importantly cheaper missiles and even more cheap drones can perform supression of enemy air defences and/or air support. Unless you're fighting the US or China, 4th gen jets are plenty. And even against US and US defended locations, cheap drones and missiles have been able to influct some pretty serious damage to critical infrastructure (like extremely expensive and rare radar systems). An adversary not crippled by extreme sanctions and corruption for decades might have been able to achieve even more, even with the total lack of airpower.
It's quite likely that in about 5 years most military installations will have a mix of weapons to intercept those systems - and depending on a number of factors you could easily end up back at low performance drones being so reliably intercepted as to be a waste of munitions to deploy.
WW1 after all was based on exactly this thinking: surely the volume of an army would overcome the machine gun.
That's unlikely. Anti-drone defences will only improve, yes, but autonomous drone swarms numbering in the thousands to tens of thousands are doable today, and few weapons systems can handle the rate of launch/fire required to combat that. Especially if there are follow-up waves mixing drones and heavy missiles against which your anti-drone defences wouldn't be enough.
> WW1 after all was based on exactly this thinking: surely the volume of an army would overcome the machine gun.
But building a cheap kamikaze drone costs much less than building a human.
They're now much closer to $3000 USD+ at the low end for an ISR vehicle. $8000+ for the more capable FPV kamikazes is the estimate for Russian models.
Which is comparable to a 155mm artillery shell. But with a lot less payload.
There's already literally millions of drones being produced and used per year in that conflict - and they've made a big impact, but the stability of the frontline also reveals that the impact of "swarms" is hardly overpowering (the obsession with them is also weird - if you had thousands of assets in the air, the last thing you'd do is put them all close together).
As Iran shows, you don't need overpowering. You need to hit the enemy where it hurts them, like strategic infrastructure.
> "swarms" ... (the obsession with them is also weird - if you had thousands of assets in the air, the last thing you'd do is put them all close together)
On the contrary, a swarm allows you to overwhelm the enemy air defences, which allows you to hit targets, including those same air defences, without having to disable them first. Cf. Iran destroying a THAAD radar.
But it's also an apples to oranges comparison: THAAD is in no way designed to intercept drone threats. The story here is closer to the US started a fight without actually investing in the sort of defenses which would deal with it - i.e. with a rack of Ukranian interceptor drones as part of the air defenses, the THAAD radar likely makes it.
The real reason stealth is needed is as a counter to GBAD. Modern anti-aircraft missiles are incredible lethal.
> have no choice
That's my point. Any battlefield today is "modern", but militaries operate with what they have. From Russia to the Houthis passing via the Houthis, we've seen insane amounts of damage done on "a modern battlefield" with anything from Cold War era equipment to cheap drones assembled by a terrorist group living in the mountains with no industrial base.
Yes, if the US wants to fight China, and vice versa, it needs 5th gen jets. Everyone else doesn't need them. They're nice to have to make your job easier (like Israel vs Iran), but don't guarantee you anything (like Israel vs Iran).
But isn't that true of the F35 as well?
On it's own, I doubt it would survive much longer on the eastern front in Ukraine.
In Iran the F-35 also did not fly around freely while the ground radars were active. They had to be taken out first. For that stealth was probably useful (and in general it is).
But it is not making them invisible - and cheap sensors and AI is likely to counter it soon. Because sensors and analysis will get better over time and sensors also better and cheaper. But the stealth will remain largely the same. It cannot really be upgraded for existing jets.
The burning question is what decision would AI make in Pearl Harbor. Would it have said flock of birds? Would it be keying in on flocks of birds instead?
By all accounts the F-35 did fly freely over Iran but the weaponry for killing ground radars are all long-range stand-off weapons so that 4th gen aircraft can use them. Many times those weapons are cued by stealth aircraft within range of the ground radars but launched by 4th gen carrying them from farther away. This is pretty standard US doctrine.
The F-35 specifically was designed for environments like Ukraine. The combat there is shaped by the lack of capability like that from either side.
Autonomous flight control software is still only able to handle the simplest missions. Maybe that will change in a few years but for now anything complex requires a remote pilot, and those communication links are very vulnerable.
Torpedo boats didn't make Battleships obsolete. Aircraft carriers did. Because they could do the same role but better.
AntiTank rifles didn't make tanks obsolete. Neither did anti-tank mines. Nor anti-tank rocket launchers, nor anti-tank artillery, nor really freaking good anti-tank missiles, nor anti-tank helicopters etc etc. Turns out, putting a box of steel around soldiers is pretty much always better. IFVs are even less survivable than a tank in all cases and they have only become more important and prominent because what capability they provide is what matters.
Artillery and Air power did not make the army obsolete. Air power did not make Artillery obsolete though the USA wanted that reality.
Submarines didn't make any boat obsolete.
SAM systems did not make planes obsolete. Hell, America decided the solution to missiles aimed at your planes was fly planes at the missile launcher! And it works because war is stupid.
"Cheap drones" only work against things that haven't yet adapted to cheap drones in the exact same way that Navy had to adapt to anti-ship missiles. With EW, those "cheap" drones get less cheap. With any sort of advancement in protection, those drones get less cheap. War is about achieving physical control, and you can't really do that with cheap drones. There's always back and forth in weapons systems. We still use bayonets in the right circumstances!
Cheap drones cannot establish air superiority, and certainly not air supremacy. Actual air combat drones are far more expensive, involved, and in development than quadcopters.
The primary power drones bring is ISR, making the entire battlefield utterly transparent, including at nighttime. That's insane, and really really bad for any of us who might be forced to fight in the future, as lethality to the average soldier is likely to go up.
It's lot more about operational costs and project deliverables than plain sticker shock, and it is turning out to be a capable platform.
Same for me. I was surprised to hear that it actually competes favorably on price. And aside from early griping that it couldn't beat an ancient F-16 in a dogfight, it seems pretty capable in that regard too. Saw a demo at the last airshow I went to and that plane was defying physics. I love the 16, always will, but I definitely don't think it would hang with an F-35.
I would be interested to see how far they've brought the technology in the intervening, uh ... 30 years. Damn. That old computer (old by technology, ours was pretty new in practical terms) was the only mainframe I've ever used. Booted it up by loading a tape reel and programming registers. I still remember that the 'happy' code was something like 0B00BE in between cycles, anything else and it had crashed.
/end trip down memory lane
The F-35 is designed as a node in that network, and afaik is one of the most advanced sensor nodes. It also receives data from the network, but it is a major contributor (partly due to operating in front, often in enemy territory, etc., afaik).
Part of using the network data is having an onboard computer that can make sense of it. Even in older planes without the network input and with smaller sensor areas, pilots faced cognitive overload from trying to interpret relatively raw data from a half-dozen or more sensors each on their own output device (screen, etc). - what's a bird, what's an ally, what's a non-combatant, what's an enemy and what's a missile - all while piloting a plane, being shot at, etc. F-35's have a computer that integrates the inputs, refines the data, identifies objects, and displays that in a unified UI on ~1 screen.
Another reason for the investment in its sensors is that situational awareness is considered by far the most decisive factor in air combat. Whoever sees and shoots first tends to win. Also, it needs to survive and be effective if cut off from outside communications.
Steal helicopters have entered the chat.
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.
In today's world, the US outspends the next 10 countries combined. In normal times, it values the lives of its servicemen, and is willing to spend quite a bit to ensure dominance. So it will often have boutique gear that other countries could never afford.
The US outspends the next 10 countries combined in peace times. By comparison, Germany outspent the US on its military by a factor of 20 on the eve of WW2. Obviously once the war got going, the US' immense industrial capacity (along with the other Allies; the British Empire and the Soviet Union had the number 2 and 3 GDPs) was unstoppable.
We no longer live in the age where the US represents half of the world GDP and the bulk of that is manufacturing. China's has a larger economy in terms of Purchasing Power Parity, it has extensive manufacturing capacity, and a vast population. If push came to shove, we wouldn't be able to simply outspend them. In that hypothetical conflict we are the germany with a bunch of questionably useful wunderwaffe.
You're right: we would simply starve them (in addition to strategic bombing of all of these manufacturing centers.)
They do not possess the food calorie production to sustain their population, nor do they have the arable land to magically begin to do so.
> we are the germany with a bunch of questionably useful wunderwaffe.
We have outstanding fast attack submarines which can't be stopped by ASBMs: exactly zero freighters carrying food from South America or crude oil would be permitted.
Today the US has 55 fast attack submarines, each of which can carry about 50 torpedos at a time. So with 100% of your subs deployed you can sink maybe 250 ships. The US has an inventory of about 1000 torpedos so you can do that about 4 times. Shanghai alone receives 230 ships per day. So The US submarine force is roughly capable of shutting down the equivalent of 1 chinese port for a few days. Realistically, your not even going to get anywhere near that. 30% of your subs are going to be out of service at any given time, more will be transiting between service bases and the war theater, only a portion of those can be spare for commerce raiding, it takes time to locate targets, and you will suffer attrition to ASW. After those first few days it becomes a race between US torpedo production and Chinese ship building. The US can produce 10 torpedos per month; China produces 15 ships per day.
Of course China isn't an island - it can import food from its neighbors by land connections. Nor is it even deficient in domestic food production capability. It grows 700 million tons of grain per year which is enough to sustain 3.8 billion adults. It imports a lot of food in peacetime because people want more than bare subsistence, and certainly interdicting trade will piss them off quite a bit, but it's not going to bring them to their knees.
The idea that in a peer war it will only be them suffering - their trade will be interdicted, their industrial centers will be bombed - and they won't have any means to strike back is exactly the complacency I was referring to. Maybe if war broke out tomorrow it would go that way, but that's merely an argument that China is not yet truly our peer. We must plan under the assumption that somebody, and it might not be China, will in the coming decades reach the point where they can tank a hit from us and hit back.
And this strategy was enormously effective. Absent U.S. intervention, Europe was fucked.
> The Allies just made ships faster than they could be sunk.
Not "the Allies" - just one Ally, separated by an entire ocean. No such separation exists today.
> Today the US has 55 fast attack submarines, each of which can carry about 50 torpedos at a time. So with 100% of your subs deployed you can sink maybe 250 ships
We had torpedo bombers in 1940, as well, submarines aren't the only ASW mechanism that exists. How many sunken ships in each port will bring them to a grinding halt? Are they magically going to tug millions of tons of steel out of these harbors?
> China produces 15 ships per day
When their shipbuilding operations aren't strategically bombed into oblivion, sure.
> it can import food from its neighbors by land connections
Now it's a World War - why would this be allowed?
> grows 700 million tons of grain per year
With several hundred million of those tons of grain (along with vast amounts of other relevant food calories - livestock, etc.) being grown in the Yangtze basin, courtesy of the fact that the Three Gorges Dam is allowed to exist. Why would the U.S. allow that dam to remain intact? This one structure is a cheat code: knock out 50% of enemy food production, displace or kill hundreds of millions of people creating a mass humanitarian crisis and subsequent Cultural Revolution, and hobble huge amounts of industrial production. Short of theoretical attacks like EMP, no such non-WMD single-point-of-failure exists anywhere in the United States.
Nuclear response is truly the only thing keeping the peace.
Supply is one part, being able to repair is another. The tiger was a massive pain in the dick to fix. It had a weak gearbox that took _hours_ to get to.
Plus most of the parts were bespoke, which means lots more tooling needed to service everything. The other thing is that germany wasn't actually that mechanised compared to the french, or english
Which is exactly the topic under discussion.
> The fictional Airwolf is an advanced prototype supersonic helicopter with stealth capabilities and a formidable arsenal.
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:
AFAICS it's a turbojet tilt-rotor with folding rotors? Is that a fair summary?
Sounds fun but also somewhat terrifying. The more complexity, the lower the MTBF.
The Osprey is amazing, can’t wait to see what the X-76 can do.
Seems like some kind of GI Joe fantasy that's gone on for too long.
I guess the idea is that you ground transport it past air defenses and accomplish objectives?
> Achieve cruise at speeds exceeding 400 knots
You wrote:
> Not a substantial enough speed increase to powerfully deter air defenses.
https://www.twz.com/air/new-hypersonic-strike-recon-aircraft...
Or I guess you mean /stellar?
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.
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
My understanding of these VTOL aircraft is they need to travel a long way, quickly, and set down in far less predictable conditions.
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.
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.
Not when you simply don't use them for horizontal flight. You just shut the VTOL hatches and forget that you aren't a conventional airplane until you want to land but there isn't an airstrip.
Winged operation has to be efficient, no doubt about that. But hovering does not need much endurance when it's only for getting away from the ground and setting down.
Electric has the power density, even more so when you don't need the power for a long time (heat buildup, no need for an equilibrium). Electric suffers from energy density, but that's where the winged mode comes in (old fashioned jet turbine, with the generator slightly larger than usual so that you'll have full batteries for the short landing hover)
https://hn.algolia.com/?dateRange=all&page=0&prefix=false&so...
https://hn.algolia.com/?sort=byDate&dateRange=all&type=comme...
Do technical writers work on press releases? This sounds more like a job for the public relations/corporate communications department.
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.
They are still very deeply limited by compressor technology, regardless of whether they use combustion or electric propulsion.
But those of us who know less don't have that information, and since the comment didn't explicitly deliver it, there's no way to learn from it. What to you is a compressed valid opinion ends up landing like a shallow dismissal.
What works better on HN is for the commenter to share some of what they know, so the rest of us can learn, and so the comment itself becomes substantive with supporting information, details, etc. Then we won't just know that you disapprove of, e.g., a particular aircraft design, but will also have some idea of why.
It can be hard to remember to do this, because most of us take the extra state in our heads for granted.
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.
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.
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.
https://www.twz.com/38435/this-is-all-the-survival-gear-that...
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.
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.
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.
There are some rather bizarre examples such as Gaza attacking Israel, despite getting something like 50% of their electricity and 10% of their fresh water from Israel!
Attacking the supplier of critical civilian and industrial inputs would seem like a mistake nobody in their right mind would make, but... there you go.
I wouldn't be surprised if a future conflict with China over Taiwan would be primarily economic.
They threaten to stop shipping, we threaten to cut off the Internet and their banking, etc...
Similarly, the most knowledgeable experts are predicting that China's strategy with Taiwan will be to simply blockade the island and wait for them to capitulate.
Last but not least, this is also Iran's current strategy. By halting shipping through the Straight of Hormuz, they're waging war on the global economy much more effectively than bombing a few small military air strips in the region.
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.
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.
I have a thermal imager. They can't see through walls in the sense you're imagining. If there's an electric heating element inside a wall or a ceiling, you could get an image of that. If there's a camera or other active electronics hidden in a wall or object, you can see the heat from that.
You wouldn't be able to see a person in an adjacent room through the wall between the two rooms, unless the wall was made specifically of thermally-transparent material.
I've heard rumours of "see through walls" equipment in the US military before. If they really have something like that, it would have to be using technology other than thermal imaging.
But when it looked like it might get cancelled pictures and exhibitions of it were suddenly everywhere.