H-20 bomber (with H-X, JH-XX)

latenlazy said:

I think the issue with cruise missiles is that their strike profiles tend to be predictable and a lot of defenses are tailored against them. The problem with stealth UCAVs is situational awareness and tactical versatility at point of attack. The question is whether the drawbacks of either solutuons are enough to warrant spending the high premium to have a fast attack manned option.

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there many different sizes and speeds of cruise missiles. alot of flexibility in load outs and mission route planning.
infact larger and faster bomber can work as AWACS as it can potentially fly at higher altitude and much closer to battlefield than slow lumbering AWACS. i think carrying large antenna further slows downs performance for already slow platform.
Israeli uses this approach which is consistant with high and fast.

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lcloo said:

How would H20 compare with JH-XX in carrying out effective maritime strike missions and land targets within 2,000Km from China's coast? Would H20 be an over-kill in this mission role?

Maritime strike missions would involve battles involving sea, land, air and space in and around first island chains and second island chains.

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Why would it be an over-kill? There really isn't anything else with PLAAF that you'd want to use this role. 2000 km off the coast would allow them to carry full payload from further into mainland without needing aerial refueling. It can also fly non-straight path that would be harder for air defense system to track. It's also close enough where J-20 can perform escort roles with aerial refueling. It would also be able to command UCAVs with shorter range.

I don't see how a JH-XX would be able to haul anywhere near the same amount of payload or have comfortable range without aerial refueling. You can argue its more survivable with its speed, but it would be less stealthy than H-20. And if it is actually supersonic, I don't see it actually being cheaper than H-20.

When you have to drop a bunch of heavy payload against ships or air defense, you'd want to do it with an aircraft with higher internal payload.

tphuang said:

Why would it be an over-kill? There really isn't anything else with PLAAF that you'd want to use this role. 2000 km off the coast would allow them to carry full payload from further into mainland without needing aerial refueling. It can also fly non-straight path that would be harder for air defense system to track. It's also close enough where J-20 can perform escort roles with aerial refueling. It would also be able to command UCAVs with shorter range.

I don't see how a JH-XX would be able to haul anywhere near the same amount of payload or have comfortable range without aerial refueling. You can argue its more survivable with its speed, but it would be less stealthy than H-20. And if it is actually supersonic, I don't see it actually being cheaper than H-20.

When you have to drop a bunch of heavy payload against ships or air defense, you'd want to do it with an aircraft with higher internal payload.

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In terms of cost a striker sized fighter layout plane (say 25 m long 17 m wingspan) will definitely be much cheaper than a large flying wing (21 m long 52 m wingspan per B2 specs) even if supersonic.

Typically the end costs can be described by component costs, engineering costs and operational costs.

Component costs are engines, material, sensors, wiring, etc. These are always cheaper overall for a smaller plane than a larger one. It is especially true if a striker only needs 2 fighter engines while a bomber needs 4 specialized engines or the structural area is much bigger which requires more surface treatment, internal supports, etc. and not just the cost of the additional area.

Engineering costs are also lower because you can reuse some wind tunnel data from other fighters rather than having to do whole new tests for a flying wing. Control code is more similar because of layout.

Operational costs are also lower due to economies of scale with fighter engines, needing less engines, etc.

The tradeoff is payload and range. I don't think payload is everything in a naval scenario. A 10000 kg payload is more than enough for 4-5x ASM or a few racks of 250 kgs. Range is the critical question but if it has at least Flanker range then it's OK.

FairAndUnbiased said:

In terms of cost a striker sized fighter layout plane (say 25 m long 17 m wingspan) will definitely be much cheaper than a large flying wing (21 m long 52 m wingspan per B2 specs) even if supersonic.

Typically the end costs can be described by component costs, engineering costs and operational costs.

Component costs are engines, material, sensors, wiring, etc. These are always cheaper overall for a smaller plane than a larger one. It is especially true if a striker only needs 2 fighter engines while a bomber needs 4 specialized engines or the structural area is much bigger which requires more surface treatment, internal supports, etc. and not just the cost of the additional area.

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non-AB WS-10 will be in pretty high production. Not only for H-20, but also UCAVs. If you want to get such JH-XX close to the same level of stealth as H-20 and be supersonic, it will be very expensive. Think F-22 level of treatment on its exhaust structure.

FairAndUnbiased said:

Engineering costs are also lower because you can reuse some wind tunnel data from other fighters rather than having to do whole new tests for a flying wing. Control code is more similar because of layout.

Operational costs are also lower due to economies of scale with fighter engines, needing less engines, etc.

The tradeoff is payload and range. I don't think payload is everything in a naval scenario. A 10000 kg payload is more than enough for 4-5x ASM or a few racks of 250 kgs. Range is the critical question but if it has at least Flanker range then it's OK.

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re-use wind tunnel data from other fighters? Take a look at F-117. A VLO strike fighter would need a very interesting looking fuselage to achieve both supersonic speed and large internal payload. China have done far more research at this point with flywing design from both H-20, GJ-11, CH-7 and future UCAVs than what I would expect out of a VLO strike fighter.

How are you going to get 10t internal payload in a supersonic strike fighter? Even 3t internal payload on a twin engine aircraft would be an achievement.

FairAndUnbiased said:

In terms of cost a striker sized fighter layout plane (say 25 m long 17 m wingspan) will definitely be much cheaper than a large flying wing (21 m long 52 m wingspan per B2 specs) even if supersonic.

Typically the end costs can be described by component costs, engineering costs and operational costs.

Component costs are engines, material, sensors, wiring, etc. These are always cheaper overall for a smaller plane than a larger one. It is especially true if a striker only needs 2 fighter engines while a bomber needs 4 specialized engines or the structural area is much bigger which requires more surface treatment, internal supports, etc. and not just the cost of the additional area.

Engineering costs are also lower because you can reuse some wind tunnel data from other fighters rather than having to do whole new tests for a flying wing. Control code is more similar because of layout.

Operational costs are also lower due to economies of scale with fighter engines, needing less engines, etc.

The tradeoff is payload and range. I don't think payload is everything in a naval scenario. A 10000 kg payload is more than enough for 4-5x ASM or a few racks of 250 kgs. Range is the critical question but if it has at least Flanker range then it's OK.

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It clearly depend of the size...

JH_XX in TU-22 size or F-111 size ?

F-111 size is more for a replacement of Jh-7 and maybe some H-6. It could be interesting, JH-7 will not fly forever.

TU-22 size enter the bracket between H-6 and future H-20 and look to be to many beans in the same bracket...

lcloo said:

How would H20 compare with JH-XX in carrying out effective maritime strike missions and land targets within 2,000Km from China's coast? Would H20 be an over-kill in this mission role?

Maritime strike missions would involve battles involving sea, land, air and space in and around first island chains and second island chains.

Click to expand...

H-20 would not be as effective in that role as a dedicated supersonic stealthy theater bomber in that role, because admittedly the H-20 would not be quite as fast in terms of ingress/egress and with impacts on its survivability (what amounts to charging headlong into a large region of airspace and sea defended by a CSG).

BUT, between H-20 and JH-XX, from a range and payload perspective-- H-20 is able to do virtually all of JH-XX's missions (albeit some on a less than ideal mission profile), but there are entire missions that JH-XX cannot do which H-20 can do (namely missions that JH-XX would simply be too small for).


I've long argued that between H-20 and the idea of a notional JH-XX, the H-20 should be seen as much more important, because ultimately the H-20 is able to mostly do what JH-XX can do, but the JH-XX cannot do what H-20 can do, in terms of range and payload.


In any case we do not have any rumours of JH-XX being on the horizon at this stage, while H-20 is on the horizon/imminent, so go figure.

tphuang said:

non-AB WS-10 will be in pretty high production. Not only for H-20, but also UCAVs. If you want to get such JH-XX close to the same level of stealth as H-20 and be supersonic, it will be very expensive. Think F-22 level of treatment on its exhaust structure.


re-use wind tunnel data from other fighters? Take a look at F-117. A VLO strike fighter would need a very interesting looking fuselage to achieve both supersonic speed and large internal payload. China have done far more research at this point with flywing design from both H-20, GJ-11, CH-7 and future UCAVs than what I would expect out of a VLO strike fighter.

How are you going to get 10t internal payload in a supersonic strike fighter? Even 3t internal payload on a twin engine aircraft would be an achievement.

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F-117 was designed with 1970s computers. Look at the F-35 instead. F-35 is a 15 m plane with 10000 kg class total payload: 2600 kg internal, 6800 kg external.


You'd expect a 25 m plane (example: Mig-31, F-111) to have greater capability for internal payload. F-35 bottom weapons bays are 3.7 m in length for a 15 m fuselage. Let's say 10 m of added fuselage only gets you 5m more of weapons ( very conservative, accounting for structural components, added fuel tanks, etc but assumes you don't need much more landing gear, cockpit, etc). Assuming no change in depth or width, that increases internal payload 2.3x. that gets you to 6000 kg payload internal.

Also it's not direct reuse of data but having a starting point to analyze the data and most of all, to make practical design changes based on the data. Experience matters. Conventional layout experience is greater than flying wing experience. Hence, development costs are lower.

FairAndUnbiased said:

Well, the theory is sound. F-35 is still more survivable than a B-52.

you don't need bomber level (20000+ kg) payload. a striker level payload (~8000 kg) is enough. 4-5 cruise missiles or a rack of 20x bombs is more than enough to be scary to critical targets.

UCAV have poor situational awareness and aren't radio silent. missiles also do not have good real time situational awareness.

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Carrying a 8 ton payload internally within a supersonic capable stealth bomber with an effective combat radius (lets say 2000 kilometers), will result in a very, very large aircraft. It would probably have to be 80t MTOW (perhaps 60+t for a stealth loadout)-- smaller than the 126t of Tu-22M3, but much larger than the 45t of F-111, and over twice the MTOW of something like J-20.

I suppose what I'm saying is that carrying "only" a striker level payload for any sort of useful combat radius for a theater capable bomber/striker, will still require a pretty massive honking aircraft, because those 8t of payload must be carried internally. That's the nature of stealth aircraft.
Add on to the fact that such a large aircraft is intended to be supersonic capable.... and it will indeed be quite expensive.



The idea of a supersonic capable stealth bomber (the notional JH-XX) has to be weighed up against the H-20, the latter of which (for many years) has been accepted to be a much larger aircraft with longer range and payload than the JH-XX would have been (by virtue of being a bigger aircraft as well as a flying wing).

As far as prioritization of resources go, it is not about "JH-XX versus alternative non stealthy bomber (such as H-6K or something)" -- and more about "JH-XX versus H-20".
IMO, H-20 is much higher of a priority than JH-XX would be, simply because in terms of payload and range, JH-XX cannot carry what H-20 can carry and it cannot carry it as far as H-20, at the sacrifice of course at being slower to ingress and egress out of a battlespace as quickly as a notional JH-XX.


However, this discussion is all academic -- as of now in 2022, the H-20 is an aircraft that is expected to emerge in the next year or so, and is an aircraft whose existence has been long confirmed, meaning the PLA has already committed to it. Meanwhile, we've had some rumours of JH-XX on and off, but no consistent, clear rumours regarding any sort of commitment to JH-XX.



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In terms of the numbers for JH-XX, as far as weight and payload distribution goes, I remember we discussed this a few years ago, and I wrote this at the time -- I think the estimates I made at the time mostly still apply right now.

I think for the JH-XX to come out you would need some upgraded WS-15 variant in service.
Making yet another quad engine aircraft would be possible but really expensive.
While the US is moving towards a cheaper bomber aircraft with the B-21 China will be moving the other way.
Even the J-XY will have two engines while the F-35 has one. This will pile on and costs will go up.

gelgoog said:

I think for the JH-XX to come out you would need some upgraded WS-15 variant in service.
Making yet another quad engine aircraft would be possible but really expensive.
While the US is moving towards a cheaper bomber aircraft with the B-21 China will be moving the other way.
Even the J-XY will have two engines while the F-35 has one. This will pile on and costs will go up.

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For the record, in all the years of discussion, I think the idea of a notional JH-XX was always that it would be twin engined.
No four engined configuration was ever considered, as that would be far too large of an aircraft, and as you wrote, expensive.

For a 60t aircraft operating with a stealthy internal payload loadout, I believe two uprated WS-10s could function as interim engines, while WS-15s would naturally be the intended powerplant.


J-XY being twin engined has its own costs and benefits and industry availability relative to F-35, and in their case I don't think simplifying it to "less engines better" is the best way of looking at it.