The "sixth generation" term is just a pop-sci (pop-engineering?) and marketing term thrown when referring to such project on the media, it is not a formal goal of the project.
The goals of the project seem to be quite well defined, they selected a very specific set of advancements in aviation (composite airframe, electronic actuators, fly-by-fiber, etc), and warfare (electronic warfare, networking, microwave attack, etc). The article gives me the impression that it is a well managed pragmatic project based on some cutting edge concepts without going into "pie in the sky" territory.
It's not like America, the EU, Russia, and China get together for a little meeting every few years to agree on a common specification for the next generation of fighter jets.
Japan's government sometimes promote their project as an research/development for new generation product, I've never heared any of such projects established a new global standard, though:
- According to JGSDF their latest Type 10 MBT[1] is world's first 4th gen tank, in spite of that its spec except software feature (like C4I capability) is virtually equivalent to modern 3rd gen tanks
- Back in 80s MITI had invested over 50 billion yen into a parallel Prolog machine, labeled as a "5th gen computer"[2]
Yeah, I'm kind of surprised that anyone is still expecting fighters to be a thing beyond the current "fifth generation".
Won't UAVs, with varying degrees of autonomy, be able to outmanoeuvre and outperform a fighter that has the additional burden of having to carry a pilot and all the extra hardware associated with that?
Close in dogfighting isn't a very big part of modern air combat, the real use for crazy manoeuvrers is avoiding missiles and those are already not burdened by keeping a human operator alive.
There is some scope for a manoeuvrers competition between the larger fighter class UAVs and current gen missiles, but the purpose built and smaller machine will always win the agility fight eventually so it doesn't seem like a very fruitful contest to enter from the perspective of the fighter manufacturer.
I was going to lob a joke about Japan having already tried the drone thing in WW2 but I think the real advantage there is situational awareness. Drones might become extensions of the fighter jet, and probably the right 'next step' after all the amraam generation. I feel they're signaling that they're going for 'skin in the game'...
The advantages of UAVs are massive, numerous, and obvious.
The only military advantages I can really think of manned fighters would be the increased situational awareness of a manned craft: the pilot has a panoramic view of their surroundings thanks to the fighter's canopy and being able to look around. Although, this seems like something drones could achieve relatively easily, providing a 360 degree view to their remote pilots.
Manned craft also have the ability to function autonomously if communications are down due to jamming, I guess? Drones could proceed toward a preselected target even without comms, of course, but a based on my layman's understanding of air combat decision-making is a huge element of combat flight. Things are messy, confusing, and ever-evolving.
That last point trumps everything, really. You can't rely on preselected-target UAVs for most tasks. And we're far, far away from an AI smart enough to make those complex decisions on its own.
6th gen fighter designs are trending towards significantly larger aircraft. The amount of hardware a human needs for support is relatively fixed so as aircraft size increases, ditching the pilot becomes less and less beneficial. Most fighters are also not limited by human G endurance but rather by structural limits.
Fighters are growing in size because engagement distances have massively increased thanks to the proliferation of high quality sensors and long range missiles. This ultimately means that the fighters need to have more range (fuel capacity), more powerful (bigger) sensors, more electrical generation capacity to power those sensors, and they need carry more and larger munitions.
For an aircraft that meets those requirements you can take the pilot out and you won't see many benefits. It's still going to be large and very expensive.
Smaller, cheaper drones can supplement this but they are not a replacement.
This new airplane is basically a flying controller for UAVs and weaponized drones. I'm guessing that they prefer short-range communication with the drones so that they don't disclose the location of their command and control center.
How would it solve the problem? What about communication between the jet and C&C center? Or why not use a number of UAVs as a retransmission hubs to conceal the C&C?
Other than EMI, and weight of wire, what could possibly be the reason for the fiber optic “fly by light” system? All of the user controls are way “slow” anyway.
Something about that makes me think translation error or marketing. I can’t imagine the “drive by x” (“fly by x”) systems being so high bandwidth.
I think those are two very valid concerns when building a top of the line fighter jet. Especially if EM weapons become a more realistic threat, as each fly-by-wire wire is effectively an antenna. If you're shielding against EM weapons, the weight will quickly stack up more than just the signal wire.
> If you're shielding against EM weapons, the weight will quickly stack up more than just the signal wire.
Agreed. The signal wire while being large antenna for EMI isn’t a problem at all. Filters, rugged transceivers, chokes and your problem is solved there.
EMP is a threat where you are able to load all traces on the PCB and in the chips themselves with varying potentials instantly.
We’re used to securing transients on the signal lines. Not on the 10mm trace from chipA to chipB.
Other than EMI, and weight of wire, what could
possibly be the reason for the fiber optic “fly
by light” system? All of the user controls are
way “slow” anyway.
Those are some powerful upsides. What are the downsides, if any?
Your modulator/demodulator went from being a simple transceiver chip to a whole laser module. Fiber optics handle cuts and “wire” damage poorly compared to copper. It isn’t as easy repair or maintain, even a simple continuity test now requires specialized equipment and you can’t probe but rather need to plug in at each point, ok but what if your issue is the connector? Fiber is always point A to point B, which doesn’t mean you can’t HUB or DaisyChain or STAR, but isn’t as easy as some copper systems like CAN, FLEX, and maybe others that can just splice together. Double any complexity because these systems are redundantly run.
I’m not sure how big an issue is with EMI. Nor do I know the bandwidth. It’s just that the most complex vehicles today, they’re most well under 800kbps for the chassis bus (assuming some vehicle at 1Mpbs and 80% load). Not sure if anyone is actually making use of production 4-8Mbps systems yet. So I assume that rugged Ethernet for data haul and CAN for sensors would work as well as it is now for jets.
They must be doing some serious data transfers I don’t understand.
It's still a pretty simple system with direct detect optics, especially on such short distances. Transceivers are really inexpensive for relatively low throughput (<40GE) applications.
They do very thorough HFSS simulations for fighter jets, having RF noise immunity without having to use heavy shielded wiring is a great benefit.
Splicing can be rough, but it's by no means impossible. With the right equipment, you can expect <0.3dB loss from a splice. That's not a lot in these very short links.
> 1800C° turbine inlet temperature sounds completely unrealistic
the current max is 1600C with cooled monocrystal blades. The 1800C seems to be a worthy goal post in this situation. More advanced cooling and/or say some tungsten composite for example. Even if they end up with "just" 1700C it would still be great.
Wrt. 6th gen in general - it looks what everybody is doing is just targeting the goal posts just a bit behind the 5th (some are even basically skipping the 5th). That actually would give us the 5+th gen. The true 6th will have totally new capabilities plus of course all this advanced 5+th tech as a base. Currently it seems to me that autonomous/AI will be that new capability (on top of much improved engines, radar/sensors, stealth body). This will also as usually differentiate top players possessing the next gen capabilities from the rest wannabes.
They say 3272 degrees Fahrenheit, which is 1800 degrees Celsius. This does appear to be achievable using the ceramic matrix composite (CMC) technology, more precisely the continuous fiber reinforced ceramic matrix composite [1].
It's not degree-Kelvin, it's just Kelvin. The article's been updated to clarify, but if it only said 1,800 degrees, it'd likely be referring to degree Celsius.
Drones are great when up against an enemy without sophisticated air defense systems. Multimillion dollar aircrafts are great for contested environments.
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[ 3.1 ms ] story [ 84.3 ms ] threadPretty gutsy to embark on a multi billion project with a goal like this.
The goals of the project seem to be quite well defined, they selected a very specific set of advancements in aviation (composite airframe, electronic actuators, fly-by-fiber, etc), and warfare (electronic warfare, networking, microwave attack, etc). The article gives me the impression that it is a well managed pragmatic project based on some cutting edge concepts without going into "pie in the sky" territory.
- According to JGSDF their latest Type 10 MBT[1] is world's first 4th gen tank, in spite of that its spec except software feature (like C4I capability) is virtually equivalent to modern 3rd gen tanks - Back in 80s MITI had invested over 50 billion yen into a parallel Prolog machine, labeled as a "5th gen computer"[2]
[1]: https://en.wikipedia.org/wiki/Type_10
[2]: https://en.wikipedia.org/wiki/Fifth_generation_computer
Won't UAVs, with varying degrees of autonomy, be able to outmanoeuvre and outperform a fighter that has the additional burden of having to carry a pilot and all the extra hardware associated with that?
There is some scope for a manoeuvrers competition between the larger fighter class UAVs and current gen missiles, but the purpose built and smaller machine will always win the agility fight eventually so it doesn't seem like a very fruitful contest to enter from the perspective of the fighter manufacturer.
The only military advantages I can really think of manned fighters would be the increased situational awareness of a manned craft: the pilot has a panoramic view of their surroundings thanks to the fighter's canopy and being able to look around. Although, this seems like something drones could achieve relatively easily, providing a 360 degree view to their remote pilots.
Manned craft also have the ability to function autonomously if communications are down due to jamming, I guess? Drones could proceed toward a preselected target even without comms, of course, but a based on my layman's understanding of air combat decision-making is a huge element of combat flight. Things are messy, confusing, and ever-evolving.
Fighters are growing in size because engagement distances have massively increased thanks to the proliferation of high quality sensors and long range missiles. This ultimately means that the fighters need to have more range (fuel capacity), more powerful (bigger) sensors, more electrical generation capacity to power those sensors, and they need carry more and larger munitions.
For an aircraft that meets those requirements you can take the pilot out and you won't see many benefits. It's still going to be large and very expensive.
Smaller, cheaper drones can supplement this but they are not a replacement.
Something about that makes me think translation error or marketing. I can’t imagine the “drive by x” (“fly by x”) systems being so high bandwidth.
Agreed. The signal wire while being large antenna for EMI isn’t a problem at all. Filters, rugged transceivers, chokes and your problem is solved there.
EMP is a threat where you are able to load all traces on the PCB and in the chips themselves with varying potentials instantly.
We’re used to securing transients on the signal lines. Not on the 10mm trace from chipA to chipB.
Your modulator/demodulator went from being a simple transceiver chip to a whole laser module. Fiber optics handle cuts and “wire” damage poorly compared to copper. It isn’t as easy repair or maintain, even a simple continuity test now requires specialized equipment and you can’t probe but rather need to plug in at each point, ok but what if your issue is the connector? Fiber is always point A to point B, which doesn’t mean you can’t HUB or DaisyChain or STAR, but isn’t as easy as some copper systems like CAN, FLEX, and maybe others that can just splice together. Double any complexity because these systems are redundantly run.
I’m not sure how big an issue is with EMI. Nor do I know the bandwidth. It’s just that the most complex vehicles today, they’re most well under 800kbps for the chassis bus (assuming some vehicle at 1Mpbs and 80% load). Not sure if anyone is actually making use of production 4-8Mbps systems yet. So I assume that rugged Ethernet for data haul and CAN for sensors would work as well as it is now for jets.
They must be doing some serious data transfers I don’t understand.
They do very thorough HFSS simulations for fighter jets, having RF noise immunity without having to use heavy shielded wiring is a great benefit.
Splicing can be rough, but it's by no means impossible. With the right equipment, you can expect <0.3dB loss from a splice. That's not a lot in these very short links.
At Mach3 the SR-71 airframe got to just under 500c at the hotspots.
The reentry temperature of the space shuttle peaked at around 1600c.
1.6-1.7K is the temperature of modern afterburners so if 1800c/k is a figure of anything it would be that.
That said the turbine entry temperature for modern jet engines is about 800c so maybe the 1 was a typo.
An sacrificial ablative coating which survives 1800C° is different from a turbine spinning 25000RPM doing the same for thousands of hours.
the current max is 1600C with cooled monocrystal blades. The 1800C seems to be a worthy goal post in this situation. More advanced cooling and/or say some tungsten composite for example. Even if they end up with "just" 1700C it would still be great.
Wrt. 6th gen in general - it looks what everybody is doing is just targeting the goal posts just a bit behind the 5th (some are even basically skipping the 5th). That actually would give us the 5+th gen. The true 6th will have totally new capabilities plus of course all this advanced 5+th tech as a base. Currently it seems to me that autonomous/AI will be that new capability (on top of much improved engines, radar/sensors, stealth body). This will also as usually differentiate top players possessing the next gen capabilities from the rest wannabes.
[1] https://iopscience.iop.org/article/10.1088/1757-899X/678/1/0...