I think the most reasonable high-thrust estimates range around 142-145 kN, but IMO unlikely 155, but in fact we don't know.
J-20 5th Generation Fighter VII
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I think the most reasonable high-thrust estimates range around 142-145 kN, but IMO unlikely 155, but in fact we don't know.
I just noticed, that changed the status of the 85th Air Brigade at Quzhou as being under conversion to J-20s.
Anyone with any explanation why they think it is getting them? AFAIK they are in fact from the 9th Brigade at Wuhu and at Quzhou due to air base renovations.
Anyone with any explanation why they think it is getting them? AFAIK they are in fact from the 9th Brigade at Wuhu and at Quzhou due to air base renovations.
That's bizarre. I thought that the transfer was only temporary. But they should be the next in line to get them because they have operational knowledge of the aircraft.
Because a lot of J-20s are being built and they have to go somewhere.
Not just here - even nozzle terminology in professional literature isn't exactly stringent or consistent in this regard. I've seen a SNECMA document calling the M88 nozzle convergent (though to be fair, it was written/translated in/to English and which clearly not the authors' strong suit)! The whole issue is compounded by manufacturers occasionally coining their own names and the fact that the secondary (ejector) nozzle sometimes isn't part of the engine at all, rather than airframe-mounted (SR-71, MiG-23, F-106). This outer nozzle need not be variable, BTW - see the F-106.
I prefer to call designs of the M88 (and related) kind convergent ejector nozzles for all the reasons you state, which seems to get the essential points across without too much confusion. A convergent nozzle (in the literal sense) has no supersonic expansion, hence the ejector part, but it remains suitably distinct from "convergent/divergent" which in this context implies both parts are mechanically controlled. The term iris nozzle for the latter type is pretty uncommon and has significant potential for confusion with iris-type throttle restrictors, so is a case in point really. Last but not least, what is called a bell nozzle in rocketry is technically also a (fixed, contoured) convergent/divergent nozzle...
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You'll have to take that up with SNECMA/Safran, who did a lot of experimental work on nozzle IR signature reduction for the M88 and claim it played a role in the choice of configuration. You could be right as far as plume signature is concerned, but that may not have been the aim - decreasing aft fuselage skin and nozzle petal temperatures is a plausible objective too.
plawolf
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The change from irising nozzle was almost certainly done for RCS reasons.
With an iris nozzle, the external geometry will constantly be changing with thrust, that can produce RCS spikes.
With a fixed external nozzle, RCS is much more stable and easy to manage without needing to put limits on engine power output.
Such a nozzle design probably also have IR reduction benefits as they could duct cold air to run between the outer and inner nozzles, thereby creating a thermal layering effect to reduce the observable IR signature of the engines.
With an iris nozzle, the external geometry will constantly be changing with thrust, that can produce RCS spikes.
With a fixed external nozzle, RCS is much more stable and easy to manage without needing to put limits on engine power output.
Such a nozzle design probably also have IR reduction benefits as they could duct cold air to run between the outer and inner nozzles, thereby creating a thermal layering effect to reduce the observable IR signature of the engines.
Spinning to the moon
plawolf
Lieutenant General
Just a few more...
Interesting that they have clipped all the trailing edges except for the main wing tips.
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