PAK FA and Su35 are quite similar.

[Thunder Bolt]

 

[Sipahi]

but one is stealth and 5th Gen jet

 

[Dr Gupta]

PAK-FA project is just starting it will change a fair bit in the next 10-15 years with new engines, materials etc

 

[Mughal-Prince]

That's Hardly 5%
Landing gears are similar rest won't look similar to me :/

 

[Ultima Thule]

but one is stealth and 5th Gen jet

but PAKFA is not a true stealth jet like F-22 and F-35 its like a 4.5++ with semi stealth tech

 

[Dr Gupta]

This is a good picture

but PAKFA is not a true stealth jet like F-22 and F-35 its like a 4.5++ with semi stealth tech

Any evidence for that? How can you judge a project which is not even finished?

India, Russia to Resume Co-Development of 5th Generation Fighter Jet / Sputnik International


Compare them in 10 years to see if they are 5th gen

 

[Sipahi]

but PAKFA is not a true stealth jet like F-22 and F-35 its like a 4.5++ with semi stealth tech

It is going to compete F22 so changes will happen

 

[Optimos Prime IA]

Apples and oranges

 

[Ultima Thule]

It is going to compete F22 so changes will happen

But it will not have all aspect stealth like F-22 and F-35 look at the front it has a IRST which may increase RCS, look at LEVCON which also increase RCS, look at engine intake, engine fanblade is exposed to radar, look at the rear fuselage it is totally unstealth, its engine is not sheilded from below, so it is basically improve SU-35 with frontal stealth only

 

[Indus Falcon]

But it will not have all aspect stealth like F-22 and F-35 look at the front it has a IRST which may increase RCS, look at LEVCON which also increase RCS, look at engine intake, engine fanblade is exposed to radar, look at the rear fuselage it is totally unstealth, its engine is not sheilded from below, so it is basically improve SU-35 with frontal stealth only

Kindly explain how will having an IRST increase an air crafts RCS ?

 

[Ultima Thule]

Kindly explain how will having an IRST increase an air crafts RCS ?

I mean slightly from the front, in air to air war

 

[Indus Falcon]

I mean slightly from the front, in air to air war

I'm no expert on RCS, but my understanding is that built in IRST, actually has no bearing on the RCS whatsoever. Please correct me if I'm wrong.

 

[nForce]

World is a better place without these things.

 

[soldier of Putin]

PAK FA looks way better. It is a very broad plane.

 

[gambit]

I'm no expert on RCS, but my understanding is that built in IRST, actually has no bearing on the RCS whatsoever. Please correct me if I'm wrong.

Not true.

EVERYTHING on a body is a contributor to final RCS. Literally EVERYTHING.

The above is an example of how just a small depth on a flat surface can amplify a return radar signal via multiple reflections. That small depth can be a panel gap, which is inevitable on all aircrafts, or a gouge from a tool or someone's boot. The amount of contributorship, meaning the energy level, depends on the radar signal's angle of incident (approach) and the energy level of that signal. Finally, as the aircraft moves and/or maneuver, this contributorship will appear and disappear.

The contributorship, or reflected energy level, of any structure, large or small, can be calculated if measure as a standalone structure, meaning if you want to measure the reflected signal from a screw, you measure only the screw. But the moment you put many many many structures together, measurement calculations gets exponentially complex because reflected signals interferes with each other. The interference falls under two types: destructive and constructive.

Destructive interference is good, basically speaking. This is when signals cancels out each other due to phase/amplitude/freq differences. Between two signals, one maybe completely cancelled out and the other diminished. Or both may completely destroys each other. So for RCS controls, destructive interference is desirable.

Constructive interference is evil, basically speaking. This is when signals amplifies each other due to similarities in phase/amplitude/freq. For RCS controls, constructive interference is not desirable.

When facing a really complex structure like an aircraft, anyone who says so-and-so structure, no matter how large or small, have no relevance in final RCS -- is a liar. Or does not know what he is talking about. If the Americans, and no doubt the Chinese, have strict maintenance procedures on their 'stealth' fighters regarding these small depths on the surfaces of their fighters, then how can anyone say the canards or the IRST sensor bulge do not contribute to final RCS ? These arguments in defense of their nations' fighters contradicts the laws of physics.