Global 6th Generation Fighter Aircraft Projects

[randombully]

I think fighter aircraft design peaked with YF-23 but I could be a bit biased for YF-23

peaked with YF-23 but I could be a bit biased for YF-23

The intakes were problematic in more than one way.
Not a complete s duct style, fan blades were exposed from some angles(and unlike su57 it didn't have any radar blockers).
Less effective in breaking down supersonic air into subsonic compared to yf22's intakes, so somewhat lower supersonic performance.




The IWB was smaller than yf22, and rotary or deep configuration was proposed, which would be mean if lower missile/bomb fails to launch the ones on top will too, unlike f22 iwb, where missiles are put side by side.


Less manurable that yf22.

The engines were too far apart, will be lot mode harder to fly if one engine fails, due to assymtric thrust and not having and tvc plus lack of manurablity specially compared to yf22.


Now in what areas it was better than yf22?
somewhat More stealthier from sides and more stealthier from back.


So what peak?


Infact, a new render was shown few years back, where the artist modified the design to solve lots of problems yf23 had( better intakes those serrated intake nozzels were better suited for supersonic flight also more stealthier, more closer engines, better Internal weapons bay, better tail) so brought the design of yf23 on par with yf22 in these areas, still being more stealthy from sides and back relative to yf22
But still can't compete with yf 22 in manurablity.



The one with bigger iwb is the modified design by the artist, also has more swept back tails, more closer engines, better intakes.
Also putting engines more closer also hid the engines better like an s duct, along with dealing with the problem of assymtric thrust.









As said before With these changes this newer design is much better in terms of side and back stealth compared to yf22, but still less manurable than tf22
This design could compete with yf22, and could win if usaf chose to sacrifice supermanurability for better stealth from other angles other than front.
But this design was not competing with yf22.


Another factor is yf22 after winning against yf23 because of being a better aircraft
Still went under further design optimization and became F-22.


So Once again.
What peak?
The original yf23 was just not as good of a design as yf22 was.
It's just people on internet hyping It up, because it "looks" alien Like.

 

[pipebomb]

The intakes were problematic in more than one way.
Not a complete s duct style, fan blades were exposed from some angles(and unlike su57 it didn't have any radar blockers).
Less effective in breaking down supersonic air into subsonic compared to yf22's intakes, so somewhat lower supersonic performance.




The IWB was smaller than yf22, and rotary or deep configuration was proposed, which would be mean if lower missile/bomb fails to launch the ones on top will too, unlike f22 iwb, where missiles are put side by side.


Less manurable that yf22.

The engines were too far apart, will be lot mode harder to fly if one engine fails, due to assymtric thrust and not having and tvc plus lack of manurablity specially compared to yf22.


Now in what areas it was better than yf22?
somewhat More stealthier from sides and more stealthier from back.


So what peak?


Infact, a new render was shown few years back, where the artist modified the design to solve lots of problems yf23 had( better intakes those serrated intake nozzels were better suited for supersonic flight also more stealthier, more closer engines, better Internal weapons bay, better tail) so brought the design of yf23 on par with yf22 in these areas, still being more stealthy from sides and back relative to yf22
But still can't compete with yf 22 in manurablity.
View attachment 29090


The one with bigger iwb is the modified design by the artist, also has more swept back tails, more closer engines, better intakes.
Also putting engines more closer also hid the engines better like an s duct, along with dealing with the problem of assymtric thrust.

View attachment 29091





View attachment 29092

As said before With these changes this newer design is much better in terms of side and back stealth compared to yf22, but still less manurable than tf22
This design could compete with yf22, and could win if usaf chose to sacrifice supermanurability for better stealth from other angles other than front.
But this design was not competing with yf22.


Another factor is yf22 after winning against yf23 because of being a better aircraft
Still went under further design optimization and became F-22.
View attachment 29093

So Once again.
What peak?
The original yf23 was just not as good of a design as yf22 was.
It's just people on internet hyping It up, because it "looks" alien Like.

Great post first of all. Very informative.

I didn't know yf-23's IWB was smaller than yf22. Is it something specific to yf-23 specifically because It seems counterintuitive that a spaced apart engine concept would have less IWB space

Every aircraft is a product of design choices/compromises. J-36 has top mounted air intakes i don't know how will it perform in high AOA. But they think it's a good compromise. Every aircraft has its

A stealth aircraft with spaced apart engines, long IWB and underbody air intakes seems to me the best compromise to me even if it compromise a bit of manurablity. That's why I really like yf-23's and su57's design. The only thing I am not a huge fan of are yf-23's trapezoidal wings

 

[Bhartiya Sainik]

I bet f47 will have the same (or inspired) air intake as yf23 and similar longitudinal IWB

I bet the opposite

As long as a good S-duct is made & other aerodynamic optimizations done, the intake can expand sideways or downwards.
In short - NG didn't exploit the airframe length for the ducts, the intake start few feet behind cockpit. While in F-22 the intake start right after cockpit ends & bending of duct starts right after. It is important to create space of IWB also. The duct contour is visible in front portion of IWB.
After YF-22, in F/A-22 LM made changes. So NG might have made the change as well if they won. But still although YF-23 went faster & had lower RCS from primary angles, the 22 has been a better choice overall, as explained above so far.

Now we have to see what will NGAD & F/A-XX do with shape, angle, position & spacing of intakes.

 

[Bhartiya Sainik]

Great post first of all. Very informative.

I didn't know yf-23's IWB was smaller than yf22. Is it something specific to yf-23 specifically because It seems counterintuitive that a spaced apart engine concept would have less IWB space

Every aircraft is a product of design choices/compromises. J-36 has top mounted air intakes i don't know how will it perform in high AOA. But they think it's a good compromise. Every aircraft has its

A stealth aircraft with spaced apart engines, long IWB and underbody air intakes seems to me the best compromise to me even if it compromise a bit of manurablity. That's why I really like yf-23's and su57's design. The only thing I am not a huge fan of are yf-23's trapezoidal wings

J-36 is not an agile fighter design but supersonic attack jet. LOAL mode AAMs are already reality. The challenge is to escape gun-fight which can be done with DEW.
If they develop their proper powerful engine in time then production J-36 might have only 2 engines. They might even modify other parts of airframe.

 

[randombully]

Great post first of all. Very informative.

I didn't know yf-23's IWB was smaller than yf22. Is it something specific to yf-23 specifically because It seems counterintuitive that a spaced apart engine concept would have less IWB space

Every aircraft is a product of design choices/compromises. J-36 has top mounted air intakes i don't know how will it perform in high AOA. But they think it's a good compromise. Every aircraft has its

A stealth aircraft with spaced apart engines, long IWB and underbody air intakes seems to me the best compromise to me even if it compromise a bit of manurablity. That's why I really like yf-23's and su57's design. The only thing I am not a huge fan of are

I didn't know yf-23's IWB was smaller than yf22. Is it something specific to yf-23 specifically because It seems counterintuitive that a spaced apart engine concept would have less IWB space

Yf23 is very flat relative to yf22.
And you need depth to put iwb, not only just for space, but also depth to add strengthening structures, because an iwb is ultimately an cavity in the airframe, that needs a lot of strengthening support due to how much stress aircrafts airframe need to handle in its flight and manurablility.
So that space between engines is not suitable for iwb.

If you wanna put the iwb there then the entire design will need to be redo from scratch, need to redistribute the subsystems in that area into other areas, plus massive changes in wings, tails, fuselage for change in centre of gravity and redistributed subsystems, which will further change aerodynamics so further changes will be needed etc.
So basically an "entirely new "aircraft design which would "somewhat" resemble yf23.

 

[Bhartiya Sainik]

Yf23 is very flat relative to yf22.
And you need depth to put iwb, not only just for space, but also depth to add strengthening structures, because an iwb is ultimately an cavity in the airframe, that needs a lot of strengthening support due to how much stress aircrafts airframe need to handle in its flight and manurablility.
So that space between engines is not suitable for iwb.

If you wanna put the iwb there then the entire design will need to be redo from scratch, need to redistribute the subsystems in that area into other areas, plus massive changes in wings, tails, fuselage for change in centre of gravity and redistributed subsystems, which will further change aerodynamics so further changes will be needed etc.
So basically an "entirely new "aircraft design which would "somewhat" resemble yf23.

That concern of mechanical strength in a flatter jet is true. But it seems that has been taken care in form of Su-57 which IMO is more agile than F-22.
I scaled the halves approximately of front views of Su-57 & YF-23:



This also shows that YF-23 had big upward bump of engine bays & Su-57 hangs down its engines so much. Both jets have minimum forward fuselage, nose, but the airframe will bulge out somewhere due to tandem IWBs.
The space used by rear IWB in Su-57 is used for other parts in YF-23 bcoz of exterior gap b/w its engines. That gap might be to lessen cross section area as per sonic drag area rule. if that gap needs to be filled then the intake area cross section needs to be bigger.

 

[randombully]

That concern of mechanical strength in a flatter jet is true. But it seems that has been taken care in form of Su-57 which IMO is more agile than F-22.
I scaled the halves approximately of front views of Su-57 & YF-23:

View attachment 29123

This also shows that YF-23 had big upward bump of engine bays & Su-57 hangs down its engines so much. Both jets have minimum forward fuselage, nose, but the airframe will bulge out somewhere due to tandem IWBs.
The space used by rear IWB in Su-57 is used for other parts in YF-23 bcoz of exterior gap b/w its engines. That gap might be to lessen cross section area as per sonic drag area rule. if that gap needs to be filled then the intake area cross section needs to be bigger.

And these changes will change how aircraft behaves aerodynamically, will change how much load and stress is in which section, will changes how much the aircraft vibrates and which section vibrate in flight.
So Need to make further changes to compensate for this.
And ultimately you need to redisgn the modified jet from scratch.

In Modern jets due to their complex aerodynamics and "load sharing" changes in one area will affect rest of the aircraft.

Like, for example if su57 changes just is irst with eots.
They will need to do wind tunnel test with a model, make extra modifications on nose, calibrate the FBW, and do the rcs test again, then finally first flight to check how it flies, how much drag is generated, whether it affects the airflow to intake etc etc.
Just for placing rst into a separate section of nose and covering with crystal dome.
Can take months to more than a year.

Now If something as drastic as IWB is to be created, you can imagine.

 

[Bhartiya Sainik]

And these changes will change how aircraft behaves aerodynamically, will change how much load and stress is in which section, will changes how much the aircraft vibrates and which section vibrate in flight.
So Need to make further changes to compensate for this.
And ultimately you need to redisgn the modified jet from scratch.

In Modern jets due to their complex aerodynamics and "load sharing" changes in one area will affect rest of the aircraft.

Like, for example if su57 changes just is irst with eots.
They will need to do wind tunnel test with a model, make extra modifications on nose, calibrate the FBW, and do the rcs test again, then finally first flight to check how it flies, how much drag is generated, whether it affects the airflow to intake etc etc.
Just for placing rst into a separate section of nose and covering with crystal dome.
Can take months to more than a year.

Now If something as drastic as IWB is to be created, you can imagine.

High skilled professionals like doctors, engineers, pilots, etc study a lot, get trained for years then do their daily work seeing which low skilled citizens or other domain professionals panic & think like OMG
When doctors, engineers, etc look at skilled bus driver driving well on dangerous roads, mountains, etc, they also react like OMG
Some humans are humble, some like show-off how tough & big job they do.
It is daily routine of different types of engineers to deal with complexity involving PCM. We're already decades into era of robotics, different types of automation & S/w, electronic devices, supercomputing & now AI/ML to do the homework. This is not 1980s.
BTW, every PCM theory champion is not practically good.