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

JH-XX is a next generation fighter bomber that will replace JH-7. JH is abbrev for Fighter Bomber in Chinese. "J" = Fighter and "H" = Bomber. So, to estimate the weight of JH-XX, using SU-34 as a comparison is more appropriate.

And H-XX is a next generation strategic bomber to replace H-6.

Bltizo said:

Erm, I hate to bring up this again (I just realized you actually made a reply to me on this point), but I think my entire argument is still not understood. My position has been that JH-XX's stealth would mean it can have a lower T/W ratio (AKA relatively poorer kinematic capability) compared to a non-stealthy aircraft like Tu-22M, if both were to attempt to conduct egress under the same conditions.

In other words, we're not just comparing T/W ratios of supersonic bombers as the contributors to successful egress, but also the contribution of stealth for JH-XX.
So, if we were to put both JH-XX and Tu-22M into the same egress situation, my position is that JH-XX can afford to have a degree of poorer kinematic capability because its stealth would synergize with its (lower, relative to Tu-22M but still supersonic) kinematic capability to allow it to potentially escape its pursuers, whereas Tu-22M has a very large RCS and is non-stealthy, therefore it must rely only on kinematic capability to escape pursuers, thus meaning it requires greater kinematic capability than JH-XX (ignoring other things such as ECM, etc, that may be available for both aircraft).
[obviously, if JH-XX had equal or greater kinematic capability than Tu-22M on top of its advantage in stealth, that would allow it to conduct successful egress to an even greater degree]

If you can accept that position, then the next logical question (which neither of us can really answer and I don't expect us to seriously know) is to consider just how much stealth would contribute to JH-XX's ability to conduct egress and what the minimum degree of kinematic capability it would need on top of its stealth to successfully egress... and whether WS-10s could potentially successfully meet that minimum kinematic capability.

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A JH-XX will be getting closer to its targets than a Tu-22M. Thus it will need better kinematics. As I said earlier, stealth helps you get closer, but doesn't help as much with escape, because launching your weapons will mean giving interceptors an approach vector to target and because your tail will always be easier to detect than your nose just by function of where the engine is pointed, especially against modern IR sensors. If you want something to escape through stealth alone, stay subsonic (but that does poorly when you have active air patrols with modern early warning systems).

latenlazy said:

A JH-XX will be getting closer to its targets than a Tu-22M. Thus it will need better kinematics. As I said earlier, stealth helps you get closer, but doesn't help as much with escape, because launching your weapons will mean giving interceptors an approach vector to target and because your tail will always be easier to detect than your nose just by function of where the engine is pointed, especially against modern IR sensors. If you want something to escape through stealth alone, stay subsonic (but that does poorly when you have active air patrols with modern early warning systems).

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Latenlazy, that is not my argument.

My argument is for a situation when JH-XX and Tu-22M are both conducting egress under the same conditions and same distances.

What you are discussing is an entirely different scenario, and is one where the ability for both to conduct egress is not assessed in fair conditions. Obviously, if we were to compare the ability of two things to conduct a job (such as egress in this case) it should be measured under the same conditions (same distance from target, same pursuers, same external environment) for it to be a fair comparison. Having one of the aircraft have the ability to remain at a greater distance is not a fair comparison of their ability to conduct egress, all that reflects is that the Tu-22M is unable to get into standoff range to use its weapon in the first place.

Skywatcher said:

The Russian Object 54C had a MTOW of 100 tons, though it was longer at 35 meters, and had variable geometry wings (which likely would add a fair amount of weight). Its powerplant were two afterburning engines (AL-41F?) with each a total thrust of 40 tons.

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To clarify, each engine on the Object 54C would have 20 tons of thrust.

Bltizo said:

Latenlazy, that is not my argument.

My argument is for a situation when JH-XX and Tu-22M are both conducting egress under the same conditions and same distances.

What you are discussing is an entirely different scenario, and is one where the ability for both to conduct egress is not assessed in fair conditions. Obviously, if we were to compare the ability of two things to conduct a job (such as egress in this case) it should be measured under the same conditions (same distance from target, same pursuers, same external environment) for it to be a fair comparison. Having one of the aircraft have the ability to remain at a greater distance is not a fair comparison of their ability to conduct egress, all that reflects is that the Tu-22M is unable to get into standoff range to use its weapon in the first place.

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And my point is that they will not, realistically, be conducting egress in the same conditions. The Tu-22M will not be able to get as close against naval targets with modern AWEC systems. The point I'm making is that the ceteris paribus argument you're making is not realistic for achieving the mission profile you're describing. Achievable standoff ranges are getting more difficult and pushed further outward because of modern naval defences. If they weren't, you wouldn't have needed stealth in the first place.

latenlazy said:

And my point is that they will not, realistically, be conducting egress in the same conditions. The Tu-22M will not be able to get as close against naval targets with modern AWEC systems. The point I'm making is that the ceteris paribus argument you're making is not realistic for achieving the mission profile you're describing. Achievable standoff ranges are getting more difficult and pushed further outward because of modern naval defences. If they weren't, you wouldn't have needed stealth in the first place.

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Exactly! The inability of Tu-22M to reach its launch distance in the first place due to it being detected+intercepted will mean it's unable to conduct egress, because by that point it will already have been shot down.
BUT -- I'm not talking about "realistic mission profiles", rather the entire time I've been talking about the ability of the aircraft to successfully conduct each part of a mission under the same parameters.
A strike mission in this case, is divided to "ability to conduct ingress successfully, undetected to launch distance X" + "ability to conduct egress successfully", as separate hypothetical scenarios, each with its own likelihood of success for each aircraft. If one then wants to look at an overall likelihood of mission success, one could multiply the two probabilities together.

For example, for the ingress situation, a Tu-22M wanting to get 300km of a well defended target undetected might have a 0.05 chance of doing so successfully, while a JH-XX might have a 0.95 chance of doing so under the same conditions.
Then, for the egress situation, a Tu-22M may have a 0.7 chance of getting out successfully, while a JH-XX might have a 0.9 chance of doing so, both under the same circumstances.
So a Tu-22M might have a 0.05 x 0.7 = 0.035 chance of successfully completing the mission and returning to base, while JH-XX may have a 0.95 x 0.9 = 0.855 chance of doing the same mission. [the probabilities here are just to illustrate the methodology -- dont' take the numbers too seriously]


But all this stuff about "overall mission success/realism" is additional material beyond the original point we were discussing, which can effectively be boiled down to me saying that the only fair way to compare an aircraft's potential ability to conduct egress with another aircraft, is if both were to do so under the same parameters.
What you're talking about is changing the parameters, weapons, and mission requirements for both aircraft, which effectively makes any comparison's of both aircraft's ability to survive egress null and void because they will not be experiencing the same circumstances.

lcloo said:

JH-XX is a next generation fighter bomber that will replace JH-7. JH is abbrev for Fighter Bomber in Chinese. "J" = Fighter and "H" = Bomber. So, to estimate the weight of JH-XX, using SU-34 as a comparison is more appropriate.

And H-XX is a next generation strategic bomber to replace H-6.

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I wouldn't take that for granted. There is reason to believe H-X is likely a much heavier aircraft than H-6, and JH-XX/H-18 may well only have a "fighter" role in name and may also be significantly heavier than Su-34 as well.

I wouldn't use their designations and prefixes alone to try and project their weight.


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Scratch said:

I believe using / comparing F-111A vs Tu-22M as an extrapolating base for a notional JH-XX is a bit of a stretch. These two "base" planes are of a completely different category I think, which would bring up the question what we think JH-XX is ment to be in the first place.
The Aardvark is a heavy fighter-bomber, that, in weight numbers, is very similar to todays Su-34.
The T-22M, on the other hand, is a full blown (strategic) bomber comparable to the B-1.

If the JH-XX is to be a JH type, i.e. a (heavy) fighter-bomber, I believe F-111 / Su-34 is the category to think of.

If it's ment to be the, mostly tactical, heavy strike platform / workhorse, I think that and the stealth requirements negate a variable-geometry wing setup and also a variable inlet geometry. It will also be a 2 engine layout.
I guess the combination of all that will mean a top-speed below Mach 2.
In a Su-34 type setup the space between the nacelles, when slightly enlarged, should yield enough space for a usefull main weapons bay. And then some side bays on the outside. (?)
The only issue here is that the "Fullback's" range is probably on the low side.

So at best I think slightly larger than the aformentioned at 25t empty, 50t full is sensible for what I guess JH-XX to be.
To reach the required range, aerial refueling will be a requirement anyway in that part of the world, were distances are quiet significant.

The all aspect stealth to cover the egress will obviously eat into the performance as well. The IR suppression will put a price tag on engine performance. With range and top-speed limited, it would probably have to still go rather quick without afterburner I guess. Or be a full up VLO design.

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At present, I think it's best we try to consider what the notional JH-XX would look like based on the known estimates of the dimensions and characteristics of the black model, and try to judge weight, fuel, payload, etc from there.

If we were to start fresh with an entirely new aircraft that would make the discussion much more difficult.

Bltizo said:

But all this stuff about "overall mission success/realism" is additional stuff beyond the original point we were discussing, which can effectively be boiled down to me saying that the only fair way to compare an aircraft's potential ability to conduct egress with another aircraft, is if both were to do so under the same parameters.
What you're talking about is changing the parameters, weapons, and mission requirements for both aircraft, which effectively makes any comparison's of both aircraft's ability to survive egress null and void because they will not be experiencing the same circumstances.

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Except I'm basing my analysis on what is realistic for the plane, since that's what the primary interest (based on my understanding) of the discussion is. That means looking at needed capabilities based on how the combat environment has changed, not an all else held equal condition. I'm not interested in a fair comparison, because fair comparisons don't really tell us anything about what we ought or ought not to expect with a potential JH-XX. Of *course* a JH-XX with stealth will have better survivability than a Tu-22M with the same kinematics and the same stand off distances, but what matters to a design is hitting a survivability target, not to simply be better or worse than a point of comparison.

latenlazy said:

Except I'm basing my analysis on what is realistic for the plane, since that's what the primary interest (based on my understanding) of the discussion is. That means looking at needed capabilities based on how the combat environment has changed, not an all else held equal condition. I'm not interested in a fair comparison, because fair comparisons don't really tell us anything about what we ought or ought not to expect with a potential JH-XX.

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Okay, looks like there was a degree of miscommunication.

I was under the impression that the discussion was about comparing the demands of kinematic capability of a non-stealthy vs stealthy plane necessary to successfully conduct egress (naturally, under identical combat environments). It was a yes/no question, in a way -- basically asking whether a stealthy aircraft could have less kinematic capability to conduct egress compared to a non-stealthy aircraft that could also conduct egress.

In other words, I was describing the general principle about the contributions of stealth to an aircraft's survivability, and saying that the contribution of stealth reduced the kinematic demands of that aircraft, compared to a non-stealthy aircraft aiming for that same degree of survivability.

Of *course* a JH-XX with stealth will have better survivability than a Tu-22M with the same kinematics and the same stand off distances, but what matters to a design is hitting a survivability target, not to simply be better or worse than a point of comparison.

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Isn't that a little ambitious? We don't know what the survivability target should even be, and we don't know how much more survivable stealth will make JH-XX during egress, meaning we won't know what the minimum kinematic capability JH-XX will need on top of its stealth to reach the survivability target.

That is one of the reasons why I was so intent on only comparing the stealthy vs non-stealthy aircraft egress (AKA survivability) thing as a question of principle -- because I can't even pretend to envision just how stealthy the specific aircraft is, and how capable the potential opposing side's defences may be.

Bltizo said:

Okay, looks like there was a degree of miscommunication.

I was under the impression that the discussion was about comparing the demands of kinematic capability of a non-stealthy vs stealthy plane necessary to successfully conduct egress (naturally, under identical combat environments). It was a yes/no question, in a way -- basically asking whether a stealthy aircraft could have less kinematic capability to conduct egress compared to a non-stealthy aircraft that could also conduct egress.

In other words, I was describing the general principle about the contributions of stealth to an aircraft's survivability, and saying that the contribution of stealth reduced the kinematic demands of that aircraft, compared to a non-stealthy aircraft aiming for that same degree of survivability.




Isn't that a little ambitious? We don't know what the survivability target should even be, and we don't know how much more survivable stealth will make JH-XX during egress, meaning we won't know what the minimum kinematic capability JH-XX will need on top of its stealth to reach the survivability target.

That is one of the reasons why I was so intent on only comparing the stealthy vs non-stealthy aircraft egress (AKA survivability) thing as a question of principle -- because I can't even pretend to envision just how stealthy the specific aircraft is, and how capable the potential opposing side's defences may be.

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Trying to use a hypothetical notion of survivability is analytically ambitious and prone to murky conclusions, but at the same time this conversation stemmed from whether using the WS-10s as interims would be viable, which kinda hinges on addressing is exactly that question.