For the Pak-Fa to stand a chance, doesn't it require a massive leap of faith in regards to low observably?
Depends on what you base your opinion on:
but I'd personally be very uncomfortable proclaiming that a nation short on money and working on its first stealth aircraft will be able to match the LO characteristics the Americans have been working on since "Have Blue"
If that is the base, you basically judge the fighter by your believe about Russia and not on what we have seen or heared about the fighter so far.
We know that the T50 has the same stealth shapings and internal weapon carriage capability as any stealth fighter, the only part that is not shaped so far and that the Russians don't even hide, is the engine covering, because we all know that the current engines won't be the once used in the serial production version.
We also know that the current prototypes don't use any RAM coatings or materials so far, because all they do is general flight and systems testing at this stage. We know that several sawtooth patterns are available around the airframe, again similar to all stealth fighters around the world.
So with all that in mind, there is hardly any doubt possible to say that the "T50" prototype is clearly a stealth design with similar stealth LO characteristics as other stealth fighters. And that alone is impressive, for the reasons you even mentioned, but what many people forget is, that the stealth design is only one part of beeing a 5th generation fighter, but there is much more about it!
Here is an edited Eurofighter magazin checklist to point it out:
As you can see, even from what we know so far, the final Pak Fa will offer anything a 5th generation fighter needs according to western standards and when you look closer, you will even see that it sets new bars in this generation!
Be it speed, agility, high TWRs and wingloadings at least comparable to F22s, but what is more interesting is the ammount and the capability of active and passive sensors. High power long range AESA radar with side arrays, to provide the longest detection range and widest FOV of any 5th gen fighters. L-Band AESA arrays, IRST, 360° IR sensors, to further improve the detection capabilities in active and passive areas.
So even if we assume the F22 might have a slightly lower RCS, it might not have an a clear advantage, since the latter has the better detection capabilities. The correct comparision to the current generation would be, F18SH vs Su 35. The earlier with slight RCS advantages, but the latter has a clear advantage in active and passive detection, so who will detect whom first?
Add various datalinks, satcom capabilities, the ammount of infos the sensor fusion might offer and you have a highly capable NG plattform in all regards!
It is true that the fall of the Soviet Union was a blow for the Russians and that they took long time to recover, but they didn't wasted the time and further developed their own capabilities wrt radar, passive sensors and flight performance (just look at the combination of movable LERX, all moving vertical tail and TVNs during flight maneuvers and tell me 1 other fighter that has similar capabilities combined), but also watched closely what the others developed in the meantime, to develop their own ways for similar capabilities.
That's why underestimating Russia is a big mistake!
