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.
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).
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.
https://en.wikipedia.org/wiki/Accidents_and_incidents_involv...
[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.
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.
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
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.
Steal helicopters have entered the chat.
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.
> The fictional Airwolf is an advanced prototype supersonic helicopter with stealth capabilities and a formidable arsenal.
I watched that show for years as a kid. I never knew it was both supersonic and stealth. Damn, DARPA must be jealous.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
Google tells me that a Boeing 737 flies (cruises) at 430–470 knots. Also, the A-10 Warthog only cruises at 300 knows.You wrote:
> Not a substantial enough speed increase to powerfully deter air defenses.
For modern air defenses like the Russian S-400 Triumf, pretty much all of their missiles can easily outrun (or catch!) any modern fighter jet. In your view, what speed would be "substantial enough"?https://www.twz.com/air/new-hypersonic-strike-recon-aircraft...
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.
Or I guess you mean /stellar?
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.
They are still very deeply limited by compressor technology, regardless of whether they use combustion or electric propulsion.
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.
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 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.
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.
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.
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.
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.