J-20 5th Generation Fighter VII


Bltizo

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In this paid piece from yankee (which I will not copy out of respect for him, given it is a paid subscription; this is the site however
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), he writes some information about the J-20:

- He generally says that the reliability and readiness of J-20 for a new aircraft type is quite impressive
- He states that this year, the next unit to receive J-20 will likely be a NTC unit
- From the AAM thread, "Summarizing what he wrote, he states that a new BVRAAM that will enter service with J-20 has a similar range to PL-15 but smaller diameter (allowing carriage of 6 ventrally vs 4 PL-15s), and greater ability to target stealth aircraft, and also that the kinematic properties of this new missile is designed to emphasize greater ability to target and maeneuver to stealth aircraft at medium to short ranges."
- He states that PL-15 has a capability which sounds a lot like CeC (where one aircraft launching PL-15 can be guided by a different aircraft), and again states it is dual pulse
- He states PL-10 has LOAL
- He states that an A2G missile for J-20 is in development (which we've known about for a while), but also that a Sino-SDB has entered testing
- He states the luneberg lens on J-20 can be jettisoned from the aircraft in flight
- He also strongly implies that a twin seater J-20 may make its appearance in 2020(?!)
- He states J-20 has conducted training/cooperation with 3rd gen fighters, as well as drones (no additional details)

Those are some of the newest info tidbits I can garner from the piece. If anyone else has also paid for a subscription and has access to it, I'd be happy to be corrected if there's anything I missed.


I made a more detailed translation/summary, which may be of interest:

Old info/info that can be surmised:
  • J-20 entering production with WS-10 engines since last year (per many photos that were hinted at mid 2019 and higher res by late 2019).
  • Generally that J-20 is stealthy and has demonstrated very good results, described as incredible etc. Stuff that you'd expect for a new 5th gen aircraft for an air force operating it for the first time.
  • Generic information regarding J-20 being very capable etc in the PLAAF fleet.
  • Generic information about seeking to greatly rollout logistics, tactics and J-20 airframes, given urgency to match proliferation of F-35s in the region.

New info:
  • He generally says that the reliability and readiness of J-20 for a new aircraft type is impressive, and it has been compared almost to a "veteran".
  • He states that this year, the next unit to receive J-20 will likely be a Northern Theatre Command unit.
    • Reminder: the first combat unit to receive J-20s was 9th brigade in Eastern Theatre Command. The first two units in the country to receive J-20s overall were two units whose responsibilities are tactics development unit and advanced training/strategic reserve, respectfully.
  • He states that a new BVRAAM will enter service with J-20 (or has entered service?? We've gotten some mixed messages recently on the status of it) and have a range close to PL-15 but with smaller diameter to allow carriage of 6 in the main weapons bay -- he also emphasizes that this new BVRAAM is designed to have greater ability to detect and track stealth aircraft (fighters). Connected to that last part, he says the kinematic properties of this new missile is designed to emphasize greater ability to target and maeneuver against stealth aircraft at medium to short ranges which seems to be where he thinks stealth on stealth engagements are most likely to be decisive.
    • My note: we've known that a new BVRAAM that J-20 could carry 6 internally was in the works (vs 4 PL-15s at present), but there's been some recent confusion regarding what the designation of this new BVRAAM is (some say PL-20, some say otherwise), and if it is designed for J-20 to carry 6 internally.
    • However Yankee seems very convinced it is a missile with dimensions for J-20 to carry 6 in its ventral bay, and this piece was published barely a month ago so I'll defer to him.
  • He states that PL-15 has a capability where one aircraft launching PL-15 can have the missile guided by a different aircraft (basically a type of CeC, sounds like), and states PL-15 has two way datalink and has a dual pulse motor (the last parts we've known about for a while).
  • He states PL-10 has LOAL.
  • In regards to A2G capabilities for J-20:
    • He states that an A2G missile for J-20 is in development (which we've known about for a while). He mentions a few other A2G missiles like JSM and Kh-59MK2, strongly implying the missile in development for J-20 are of a similar class (which is again consistent with what we've heard about this missile in the past).
    • He also mentions a few small size PGM (think SDB-like) weapons we've seen in the past at airshows/arms expos (FT-5, CM-506KG), and says such a weapon is in testing and implies it could enter service on J-20 in 2020. He doesn't mention specifically what model it is (if it is one of the models we have seen revealed in the past or if it's a new one entirely).
  • He states the luneberg lens on J-20 can be jettisoned from the aircraft in flight.
  • He states J-20 has conducted training/cooperation with 4rd gen fighters, as well as drones.
    • My note: we've known about the former for years now, but this is the first time hearing about the latter in an explicit manner. Unfortunately there aren't any additional details regarding what kind of training or cooperation J-20 has engaged with drones in.
  • He strongly implies that a twin seater J-20 may make its appearance in 2020(?!), and it would be a fully combat capable trainer with enhanced command capabilities.
    • My note: this is definitely the biggest eyebrow raiser for me. We've heard some superficial rumours that a twin seater J-20 might be in the works for a few years now, but this is definitely the most recent persistent mention of it from someone considered to be very credible. I'm sure we can all consider what the roles of a twin seater 5th generation aircraft may have.

=====

Additional comments regarding a twin seater from myself:

He describes the twin seater as a fully combat capable trainer with enhanced command capability.

IMO, that does not suggest to me a "JH-20" (i.e.: not an "FB-22" equivalent), but rather more of a J-10AS to J-10A. IMO the amount of work needed to develop a true "JH-20" to make such an aircraft worthwhile would be very significant and substantial structural changes.


I think that a twin seat combat capable/command variant could make sense if it can fulfill 2 (or 3) roles that a standard single seat J-20 cannot:
1. Combat capable trainer role -- the PLA likely recognizes that there is a need to enhance training capacity and training speed of J-20 pilots and having only simulators may be deemed not sufficient. The scale at which F-35s are proliferating in the region means not only is there a need to accelerate delivery of J-20 airframes themselves but also to accelerate associated development of the human resources side of things (pilots in this case; but also the crew to maintain aircraft as part of the logistics chain)
2. Combat command role -- a twin seat aircraft will allow a "systems officer" to better command and allocate tasks in a complex battlespace to friendly aircraft while the aircraft itself operates in the battlespace, in a manner that a single pilot cannot manage. The electromagnetic battle space (with stealth, EW/ECM, ESM, active and passive sensors) is only likely to become more complex in coming years, and even with sensor fusion and automation, having a number of aircraft that can have enhanced "forward battle management" capabilities may be very useful.
(3. Combat drone command role -- similar to 2. above, this is basically the same thing but having your "systems officer" also have the role of "drone command" role, to better be capable of commanding UAVs and UCAVs in the battle space while doing the same mission as aforementioned as 2.)

IMO, if the PLA was only interested in having 1 of the 3 above capabilities, it may not have made sense to develop a dedicated two seat version. I think they might have just bitten the bullet and accepted that they'll have to make do with a single seater J-20 to do the role. But if they were interested in all 3 roles, then I think together those 3 roles would be impetus enough to develop a dedicated twin seater variant.
Of course other additional secondary roles include potential for a J-20 twin seater acting as a jammer, or forward "battle space ESM/intelligence" aircraft etc, in a way that is superior to what a single seat J-20 could do.


My guess is that a "J-20AS" will likely basically have the same dimensions as a normal J-20A, but with a second seat and possibly a slightly elevated spine/dorsal bulge for avionics. The aircraft will obviously have significantly greater weight than a single seat J-20A and be less maneuvrable (though will seek to retain similar range). However it will otherwise retain the same weapons bay dimensions, same overall dimensions and control surface arrangements.

However I consider the prospect of a J-20 twin seater to be very eyebrow raising as well, but the only reason I'm taking it with some level of seriousness is because it's from yankee.
 
Last edited:

siegecrossbow

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What’s the point of jettisoning the luneberg lens? Is this for experimental purposes or a one time combat trick?
My guess is that it makes it easier for ground based radars to track the J-20, at least during the initial takeoff phase. They need to jettison that lens during the exercise so that they are stealth. The problem with this is that the ground based radars won't be able to track them for the return flight.
 

AndrewS

Major
Registered Member
I made a more detailed translation/summary, which may be of interest:

Old info/info that can be surmised:
  • J-20 entering production with WS-10 engines since last year (per many photos that were hinted at mid 2019 and higher res by late 2019).
  • Generally that J-20 is stealthy and has demonstrated very good results, described as incredible etc. Stuff that you'd expect for a new 5th gen aircraft for an air force operating it for the first time.
  • Generic information regarding J-20 being very capable etc in the PLAAF fleet.
  • Generic information about seeking to greatly rollout logistics, tactics and J-20 airframes, given urgency to match proliferation of F-35s in the region.

New info:
  • He generally says that the reliability and readiness of J-20 for a new aircraft type is impressive, and it has been compared almost to a "veteran".
  • He states that this year, the next unit to receive J-20 will likely be a Northern Theatre Command unit.
    • Reminder: the first combat unit to receive J-20s was 9th brigade in Eastern Theatre Command. The first two units in the country to receive J-20s overall were two units whose responsibilities are tactics development unit and advanced training/strategic reserve, respectfully.
  • He states that a new BVRAAM will enter service with J-20 (or has entered service?? We've gotten some mixed messages recently on the status of it) and have a range close to PL-15 but with smaller diameter to allow carriage of 6 in the main weapons bay -- he also emphasizes that this new BVRAAM is designed to have greater ability to detect and track stealth aircraft (fighters). Connected to that last part, he says the kinematic properties of this new missile is designed to emphasize greater ability to target and maeneuver against stealth aircraft at medium to short ranges which seems to be where he thinks stealth on stealth engagements are most likely to be decisive.
    • My note: we've known that a new BVRAAM that J-20 could carry 6 internally was in the works (vs 4 PL-15s at present), but there's been some recent confusion regarding what the designation of this new BVRAAM is (some say PL-20, some say otherwise), and if it is designed for J-20 to carry 6 internally.
    • However Yankee seems very convinced it is a missile with dimensions for J-20 to carry 6 in its ventral bay, and this piece was published barely a month ago so I'll defer to him.
  • He states that PL-15 has a capability where one aircraft launching PL-15 can have the missile guided by a different aircraft (basically a type of CeC, sounds like), and states PL-15 has two way datalink and has a dual pulse motor (the last parts we've known about for a while).
  • He states PL-10 has LOAL.
  • In regards to A2G capabilities for J-20:
    • He states that an A2G missile for J-20 is in development (which we've known about for a while). He mentions a few other A2G missiles like JSM and Kh-59MK2, strongly implying the missile in development for J-20 are of a similar class (which is again consistent with what we've heard about this missile in the past).
    • He also mentions a few small size PGM (think SDB-like) weapons we've seen in the past at airshows/arms expos (FT-5, CM-506KG), and says such a weapon is in testing and implies it could enter service on J-20 in 2020. He doesn't mention specifically what model it is (if it is one of the models we have seen revealed in the past or if it's a new one entirely).
  • He states the luneberg lens on J-20 can be jettisoned from the aircraft in flight.
  • He states J-20 has conducted training/cooperation with 4rd gen fighters, as well as drones.
    • My note: we've known about the former for years now, but this is the first time hearing about the latter in an explicit manner. Unfortunately there aren't any additional details regarding what kind of training or cooperation J-20 has engaged with drones in.
  • He strongly implies that a twin seater J-20 may make its appearance in 2020(?!), and it would be a fully combat capable trainer with enhanced command capabilities.
    • My note: this is definitely the biggest eyebrow raiser for me. We've heard some superficial rumours that a twin seater J-20 might be in the works for a few years now, but this is definitely the most recent persistent mention of it from someone considered to be very credible. I'm sure we can all consider what the roles of a twin seater 5th generation aircraft may have.

=====

Additional comments regarding a twin seater from myself:

He describes the twin seater as a fully combat capable trainer with enhanced command capability.

IMO, that does not suggest to me a "JH-20" (i.e.: not an "FB-22" equivalent), but rather more of a J-10AS to J-10A. IMO the amount of work needed to develop a true "JH-20" to make such an aircraft worthwhile would be very significant and substantial structural changes.


I think that a twin seat combat capable/command variant could make sense if it can fulfill 2 (or 3) roles that a standard single seat J-20 cannot:
1. Combat capable trainer role -- the PLA likely recognizes that there is a need to enhance training capacity and training speed of J-20 pilots and having only simulators may be deemed not sufficient. The scale at which F-35s are proliferating in the region means not only is there a need to accelerate delivery of J-20 airframes themselves but also to accelerate associated development of the human resources side of things (pilots in this case; but also the crew to maintain aircraft as part of the logistics chain)
2. Combat command role -- a twin seat aircraft will allow a "systems officer" to better command and allocate tasks in a complex battlespace to friendly aircraft while the aircraft itself operates in the battlespace, in a manner that a single pilot cannot manage. The electromagnetic battle space (with stealth, EW/ECM, ESM, active and passive sensors) is only likely to become more complex in coming years, and even with sensor fusion and automation, having a number of aircraft that can have enhanced "forward battle management" capabilities may be very useful.
(3. Combat drone command role -- similar to 2. above, this is basically the same thing but having your "systems officer" also have the role of "drone command" role, to better be capable of commanding UAVs and UCAVs in the battle space while doing the same mission as aforementioned as 2.)

IMO, if the PLA was only interested in having 1 of the 3 above capabilities, it may not have made sense to develop a dedicated two seat version. I think they might have just bitten the bullet and accepted that they'll have to make do with a single seater J-20 to do the role. But if they were interested in all 3 roles, then I think together those 3 roles would be impetus enough to develop a dedicated twin seater variant.
Of course other additional secondary roles include potential for a J-20 twin seater acting as a jammer, or forward "battle space ESM/intelligence" aircraft etc, in a way that is superior to what a single seat J-20 could do.


My guess is that a "J-20AS" will likely basically have the same dimensions as a normal J-20A, but with a second seat and possibly a slightly elevated spine/dorsal bulge for avionics. The aircraft will obviously have significantly greater weight than a single seat J-20A and be less maneuvrable (though will seek to retain similar range). However it will otherwise retain the same weapons bay dimensions, same overall dimensions and control surface arrangements.

However I consider the prospect of a J-20 twin seater to be very eyebrow raising as well, but the only reason I'm taking it with some level of seriousness is because it's from yankee.
I'm looking at the empty weight of an F-15C fighter (12,700kg) and F-15E strike-fighter (14,300kg)

So yes, a 2 seater would be heavier, but the difference is 1600kg.
That works out as a 12% increase in empty weight.
Or a 9% decrease in maximum payload of 18100kg

If similar figures apply to the J-20, then the additional weight doesn't look too significant.
 

stannislas

Junior Member
Registered Member
My guess is that it makes it easier for ground based radars to track the J-20, at least during the initial takeoff phase. They need to jettison that lens during the exercise so that they are stealth. The problem with this is that the ground based radars won't be able to track them for the return flight.
Oh yeah, this does remind me of an article few years ago about the difficulties of training j-20 with other aircrafts, one of the issue is that quite often j-20 is untraceable by ground radar, so they have to develop some other way to do so, and one of the unit got breakthrough something like that.

so I guess they should have someway in terms of guild j-20 landing even without luneberg lens...
 

plawolf

Brigadier
My guess is that it makes it easier for ground based radars to track the J-20, at least during the initial takeoff phase. They need to jettison that lens during the exercise so that they are stealth. The problem with this is that the ground based radars won't be able to track them for the return flight.
J20s won’t need ground based radars to nursemaid them. Airspace is highly restricted in China, and the civilian owner-pilot market is practically nonexistent, meaning the overwhelming majority of things in the skies over China are either flown by professional pilots for airlines and the like, or police and military.

Civilian air traffic stays religiously in their allotted airspace corridors (else they face sever penalties), meaning the skies are much clearer for military stuff and much less need for air traffic control to be aware of military traffic outside of the civilian corridors.

The obsession with luneburg lenses is to ensure J20s can operate with complete freedom within Chinese airspace without fear of accidentally exposing its true stealth capabilities.

This isn’t just limited to boarder regions, while hostile foreign powers routinely fly surveillance and SIGINT assets pretty much along the edge of Chinese airspace; there are also a lot of airliners with weather radars; and it would also be possible for HUMINT assets on the ground to place passive radar receivers in pre-calculated locations so they might get some interesting scratched from civilian ground control radars. There are many possible ways for hostile foreign powers to be some feeling for the J20’s stealth capabilities if they fly around clean all the time.

By always flying with luneburg lenses, China denies possible foes any chance of gathering such intel.

The ability to jettison the lenses in flight means PLAAF J20s sacrifices none of their combat potential even if they take off/are already airborne with lenses when an emerging situation develops.

PLAAF J20s can and will conduct routine CAP with luneburg lenses in peacetime; but can regain full stealth and be combat ready to the flick of a switch should be need arise.
 

Bltizo

Lieutenant General
Staff member
Super Moderator
Registered Member
I'm looking at the empty weight of an F-15C fighter (12,700kg) and F-15E strike-fighter (14,300kg)

So yes, a 2 seater would be heavier, but the difference is 1600kg.
That works out as a 12% increase in empty weight.
Or a 9% decrease in maximum payload of 18100kg

If similar figures apply to the J-20, then the additional weight doesn't look too significant.
I think a more accurate comparison would be between F-15C and F-15D rather than F-15C and F-15E. (or even F-15A to F-15B)


After all the F-15E is a dedicated strike variant of F-15D with some structural modifications inherent to the airframe to allow it, whereas the F-15D is simply a twin seater variant of the standard F-15C.


Unfortunately I'm unable to easily locate a source giving me a number for F-15C and F-15D's empty weights, but there are some sources available for other aircraft.

E.g.: for Gripen C vs Gripen D (single seater vs twin seater), their empty weights are 6.8 tons vs 7.1 tons.
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siegecrossbow

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Oh yeah, this does remind me of an article few years ago about the difficulties of training j-20 with other aircrafts, one of the issue is that quite often j-20 is untraceable by ground radar, so they have to develop some other way to do so, and one of the unit got breakthrough something like that.

so I guess they should have someway in terms of guild j-20 landing even without luneberg lens...
That was during one of the military parades (either August 1st or October 1st).
 

AndrewS

Major
Registered Member
I think a more accurate comparison would be between F-15C and F-15D rather than F-15C and F-15E. (or even F-15A to F-15B)


After all the F-15E is a dedicated strike variant of F-15D with some structural modifications inherent to the airframe to allow it, whereas the F-15D is simply a twin seater variant of the standard F-15C.


Unfortunately I'm unable to easily locate a source giving me a number for F-15C and F-15D's empty weights, but there are some sources available for other aircraft.

E.g.: for Gripen C vs Gripen D (single seater vs twin seater), their empty weights are 6.8 tons vs 7.1 tons.
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Yes, I couldn't easily find a figure for the F-15D weight either.

But a comparison with the heavier F-15E still serves to make the same point, which is that a 2 seater variant doesn't appear to impose too much of a performance/weight penalty.

Ditto for the Gripen comparison.
 

Air Force Brat

Brigadier
Super Moderator
I made a more detailed translation/summary, which may be of interest:

Old info/info that can be surmised:
  • J-20 entering production with WS-10 engines since last year (per many photos that were hinted at mid 2019 and higher res by late 2019).
  • Generally that J-20 is stealthy and has demonstrated very good results, described as incredible etc. Stuff that you'd expect for a new 5th gen aircraft for an air force operating it for the first time.
  • Generic information regarding J-20 being very capable etc in the PLAAF fleet.
  • Generic information about seeking to greatly rollout logistics, tactics and J-20 airframes, given urgency to match proliferation of F-35s in the region.

New info:
  • He generally says that the reliability and readiness of J-20 for a new aircraft type is impressive, and it has been compared almost to a "veteran".
  • He states that this year, the next unit to receive J-20 will likely be a Northern Theatre Command unit.
    • Reminder: the first combat unit to receive J-20s was 9th brigade in Eastern Theatre Command. The first two units in the country to receive J-20s overall were two units whose responsibilities are tactics development unit and advanced training/strategic reserve, respectfully.
  • He states that a new BVRAAM will enter service with J-20 (or has entered service?? We've gotten some mixed messages recently on the status of it) and have a range close to PL-15 but with smaller diameter to allow carriage of 6 in the main weapons bay -- he also emphasizes that this new BVRAAM is designed to have greater ability to detect and track stealth aircraft (fighters). Connected to that last part, he says the kinematic properties of this new missile is designed to emphasize greater ability to target and maeneuver against stealth aircraft at medium to short ranges which seems to be where he thinks stealth on stealth engagements are most likely to be decisive.
    • My note: we've known that a new BVRAAM that J-20 could carry 6 internally was in the works (vs 4 PL-15s at present), but there's been some recent confusion regarding what the designation of this new BVRAAM is (some say PL-20, some say otherwise), and if it is designed for J-20 to carry 6 internally.
    • However Yankee seems very convinced it is a missile with dimensions for J-20 to carry 6 in its ventral bay, and this piece was published barely a month ago so I'll defer to him.
  • He states that PL-15 has a capability where one aircraft launching PL-15 can have the missile guided by a different aircraft (basically a type of CeC, sounds like), and states PL-15 has two way datalink and has a dual pulse motor (the last parts we've known about for a while).
  • He states PL-10 has LOAL.
  • In regards to A2G capabilities for J-20:
    • He states that an A2G missile for J-20 is in development (which we've known about for a while). He mentions a few other A2G missiles like JSM and Kh-59MK2, strongly implying the missile in development for J-20 are of a similar class (which is again consistent with what we've heard about this missile in the past).
    • He also mentions a few small size PGM (think SDB-like) weapons we've seen in the past at airshows/arms expos (FT-5, CM-506KG), and says such a weapon is in testing and implies it could enter service on J-20 in 2020. He doesn't mention specifically what model it is (if it is one of the models we have seen revealed in the past or if it's a new one entirely).
  • He states the luneberg lens on J-20 can be jettisoned from the aircraft in flight.
  • He states J-20 has conducted training/cooperation with 4rd gen fighters, as well as drones.
    • My note: we've known about the former for years now, but this is the first time hearing about the latter in an explicit manner. Unfortunately there aren't any additional details regarding what kind of training or cooperation J-20 has engaged with drones in.
  • He strongly implies that a twin seater J-20 may make its appearance in 2020(?!), and it would be a fully combat capable trainer with enhanced command capabilities.
    • My note: this is definitely the biggest eyebrow raiser for me. We've heard some superficial rumours that a twin seater J-20 might be in the works for a few years now, but this is definitely the most recent persistent mention of it from someone considered to be very credible. I'm sure we can all consider what the roles of a twin seater 5th generation aircraft may have.

=====

Additional comments regarding a twin seater from myself:

He describes the twin seater as a fully combat capable trainer with enhanced command capability.

IMO, that does not suggest to me a "JH-20" (i.e.: not an "FB-22" equivalent), but rather more of a J-10AS to J-10A. IMO the amount of work needed to develop a true "JH-20" to make such an aircraft worthwhile would be very significant and substantial structural changes.


I think that a twin seat combat capable/command variant could make sense if it can fulfill 2 (or 3) roles that a standard single seat J-20 cannot:
1. Combat capable trainer role -- the PLA likely recognizes that there is a need to enhance training capacity and training speed of J-20 pilots and having only simulators may be deemed not sufficient. The scale at which F-35s are proliferating in the region means not only is there a need to accelerate delivery of J-20 airframes themselves but also to accelerate associated development of the human resources side of things (pilots in this case; but also the crew to maintain aircraft as part of the logistics chain)
2. Combat command role -- a twin seat aircraft will allow a "systems officer" to better command and allocate tasks in a complex battlespace to friendly aircraft while the aircraft itself operates in the battlespace, in a manner that a single pilot cannot manage. The electromagnetic battle space (with stealth, EW/ECM, ESM, active and passive sensors) is only likely to become more complex in coming years, and even with sensor fusion and automation, having a number of aircraft that can have enhanced "forward battle management" capabilities may be very useful.
(3. Combat drone command role -- similar to 2. above, this is basically the same thing but having your "systems officer" also have the role of "drone command" role, to better be capable of commanding UAVs and UCAVs in the battle space while doing the same mission as aforementioned as 2.)

IMO, if the PLA was only interested in having 1 of the 3 above capabilities, it may not have made sense to develop a dedicated two seat version. I think they might have just bitten the bullet and accepted that they'll have to make do with a single seater J-20 to do the role. But if they were interested in all 3 roles, then I think together those 3 roles would be impetus enough to develop a dedicated twin seater variant.
Of course other additional secondary roles include potential for a J-20 twin seater acting as a jammer, or forward "battle space ESM/intelligence" aircraft etc, in a way that is superior to what a single seat J-20 could do.


My guess is that a "J-20AS" will likely basically have the same dimensions as a normal J-20A, but with a second seat and possibly a slightly elevated spine/dorsal bulge for avionics. The aircraft will obviously have significantly greater weight than a single seat J-20A and be less maneuvrable (though will seek to retain similar range). However it will otherwise retain the same weapons bay dimensions, same overall dimensions and control surface arrangements.

However I consider the prospect of a J-20 twin seater to be very eyebrow raising as well, but the only reason I'm taking it with some level of seriousness is because it's from yankee.
Yep, on the issue of a 2 seat J-20 I have two words, "NYET KOMRAD!".

No one has flown a 2 seat 5Gen, the Indian's wanted one, but the Russians would not/could not deliver on their promise to build one.....

The J-20 should be as easy to fly as the F-22/F-35, so you really don't need a two seater for flight instruction, and tactically the USAF and others have found the Student/Instructor in a "two ship" seems to work very well....
 

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