World stealth fighter rankings (updated citations)
#1 F-22 Raptor - RCS is 0.0001 m2 (from
GlobalSecurity citation)
#2 J-20 Mighty Dragon - RCS is intermediate between F-22 and F-35 (Frontal and side-aspect RCS is 0.0001 m2 like F-22. Rear-aspect RCS with round LOAN engine nozzles is 0.005 m2 like F-35. See
Australia Air Power citation below.)
#3 F-35 Joint Strike Fighter - RCS is 0.005 m2 (from
GlobalSecurity citation)
#4 T-50/Pak-Fa - RCS is 0.5 m2 (from
Russian Embassy in India official website citation)
References:
GlobalSecurity:
Radar Cross Section (RCS)
Russian Embassy in India official website:
India, Russia close to pact on next generation fighter
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Australia Air Power: J-20 is a "genuine Very Low Observable design"
J-20 Mighty Dragon is a "genuine Very Low Observable design" except for round engine nozzles, which can be fixed.
The Chengdu J-20: Peace in Our Time?
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This study has therefore established through Physical Optics simulation across nine radio-frequency bands, that no fundamental obstacles exist in the shaping design of the J-20 prototype precluding its development into a genuine Very Low Observable design.
Above: L-band RCS, below X-band RCS head on, both in PCSR format (M.J. Pelosi).
Engineers and Scientists who work in ‘stealth’ (AKA ‘Low Observable’
designs have a way for explaining it to lay people: ‘Stealth’ is achieved by Shaping, Shaping, Shaping and Materials (Denys Overholser).
The F-22A is clearly well shaped for low observability above about 500 MHz, and from all important aspects.
The J-20 has observed the ‘Shaping, Shaping, Shaping’ imperative, except for the axisymmetric nozzles, and some curvature of the sides that smears a strong, but very narrow specular return into something of a more observable fan.
The X-35 mostly observed the ‘Shaping, Shaping, Shaping’ rule, but since then, to quote a colleague, ‘hideous lumps, bumps, humps and warts’ have appeared on the JSF to disrupt the shaping imperative, forcing excessive reliance on materials, which are at the rear-end of the path to ‘Low Observability’.
While discussing ‘rear-ends’, both the F-35 and the J-20 have large signature contributions from their jet nozzles. However, the difference is much like the proverbial ‘Ham Omelette’: the F-35 Pig is committed, but the J-20 Chicken is a participant.
If the Chinese decide that rear sector Low Observability is tactically and strategically important, they are at the design stage where they can copy the F-22A nozzle design for the production configuration of the J-20."
[Note: Thank you to HouShanghai and 蓝胖 for the picture.]