Sukhoi Su-57 Meta Thread

a reply to: zukli


F-22 midbody mockup




PAK-FA engine intake layout

originally posted by: drwire
a reply to: zukli

F-22 midbody mockup

PAK-FA engine intake layout

DSI hides engine much better than S duct intake does. Not only that, DSI has no moving parts. It's much lighter than traditional intake and it requires no servicing. Russia don't have DSI technology. If Russia has DSI technology Russia use it on every new plane. The fact is Su-35 and Su-57 and MiG-35 don't have DSI proves Russia don't have DSI technology like China and America do. China and America puts DSI on every new plane.

a reply to: zukli

And they get what they pay for. They still have big production issues on just about all their aircraft.

originally posted by: Zaphod58
a reply to: zukli

And they get what they pay for. They still have big production issues on just about all their aircraft.

Correct. If I'm not mistaken, Russia spends more than 5% of GDP on defense. America only recently upped defense spending to 3% of GDP and that's because of Trump. Under Obama is was about 2% of GDP.

originally posted by: drwire
a reply to: RadioRobert

not hidding enough

Picture does not reflect actual geometry of the aircraft or duct. So you're either looking at a fake photo, inlet flow vanes/radar blocker, or all of the above.

Since the only photo that shows this is a picture apparently taken at night in weather no less, I'd be pretty shocked if this photo represents reality as opposed to being manipulated.

a reply to: zukli

DSI hides engine much better than S duct intake does.

That's pretty much a throwaway statement. It also shows you didn't look at the geometry of the F-22, F-23, or Su-57 that was presented in the post you were responding to.

originally posted by: RadioRobert

originally posted by: drwire
a reply to: RadioRobert

not hidding enough

Picture does not reflect actual geometry of the aircraft or duct. So you're either looking at a fake photo, inlet flow vanes/radar blocker, or all of the above.

Since the only photo that shows this is a picture apparently taken at night in weather no less, I'd be pretty shocked if this photo represents reality as opposed to being manipulated.

According to schematics, less than half of engine shows.

upload.wikimedia.org...

originally posted by: RadioRobert

originally posted by: drwire
a reply to: RadioRobert

not hidding enough

Picture does not reflect actual geometry of the aircraft or duct. So you're either looking at a fake photo, inlet flow vanes/radar blocker, or all of the above.

Since the only photo that shows this is a picture apparently taken at night in weather no less, I'd be pretty shocked if this photo represents reality as opposed to being manipulated.

It might not be fake. Super Hornet also uses S duct and it also shows a lot of engine.

www.f-16.net...

originally posted by: RadioRobert
a reply to: zukli

DSI hides engine much better than S duct intake does.

That's pretty much a throwaway statement. It also shows you didn't look at the geometry of the F-22, F-23, or Su-57 that was presented in the post you were responding to.

The benefits of DSI goes beyond hiding engine. It is more aerodynamic than traditional intake. There is no splitter separating intake from the main fuselage. DSI is truly part of the fuselage. On top of being more aerodynamic, it is much lighter due to containing no ramps and moving parts, no need to service like traditional intake needs, and it looks better too.

I thought I would post an updated picture of the intake from that source I linked earlier.

The intake and first stage of the engine is highly shielded and uses RCS reducing electronics.

The moveable mesh keeps debris from entering the engine allowing for operation off rough runways. This mesh has a RCS reducing design supposedly.

The mesh is probably similar in design to the air outlets on the side.

Anyway, the reflection of engine is exaggerated. There is no evidence engine has more radar signature than fuselage.

a reply to: zukli

DSI is simply a method of boundary layer control. It pushes most of the boundary layer up or down away from the inlet. The F-22 uses a splitterplate to eliminate the boundary layer. It has a fixed ramp, as well ( "no moving parts"). The Su-57 uses a splitter plate also. The F-23 used a different setup. A fixed inlet is optimized for a single mach speed and is less efficient in other parts of the envelope. The reason people use heavier, more complex ducts is for higher efficiencies across the envelope. As they have done for ages. People aren't dumb.

A DSI can "also" help block the compressor face -- in the same way a properly designed duct does.

There's no "secret DSI technology" that the Russians don't have. It's modelling and trial and error. They've either decided they prefer the benefits of efficient flow variably optimized for its current speed provided for by traditional inlets or they've opted not to design a DSI designed to the parameters of the interim engine.

a reply to: zukli

????

originally posted by: tadaman

So either the blocker or flow vanes (or a device doing both). Not the face of the engine.

originally posted by: RadioRobert
a reply to: zukli

DSI is simply a method of boundary layer control. It pushes most of the boundary layer up or down away from the inlet. The F-22 uses a splitterplate to eliminate the boundary layer. It has a fixed ramp, as well ( "no moving parts"). The Su-57 uses a splitter plate also. The F-23 used a different setup. A fixed inlet is optimized for a single mach speed and is less efficient in other parts of the envelope. The reason people use heavier, more complex ducts is for higher efficiencies across the envelope. As they have done for ages. People aren't dumb.

A DSI can "also" help block the compressor face -- in the same way a properly designed duct does.

There's no "secret DSI technology" that the Russians don't have. It's modelling and trial and error. They've either decided they prefer the benefits of efficient flow variably optimized for its current speed provided for by traditional inlets or they've opted not to design a DSI designed to the parameters of the interim engine.

LM has DSI technology because they developed it in the mid 1990s. Chinese have it because they stole it. Only LM and AVIC have DSI. No other company has DSI technology.

a reply to: RadioRobert

There was this to add with the image:

RCS Reduction in various sectors of the forward hemisphere is achieved by using S-shaped air intake duct and the coating of radar absorbing materials.

But if you look closely to those images available in the public domain, diagrams and photographs, it can be concluded that the inlet guide motor vehicle (GMV), or more simply - the first stage of the compressor to blades, it seems to be very clearly visible to enemy radar. 

S-shaped channel provides only reduction of RCS in the axial directions to reduce the visibility of other sectors in the forward hemisphere, engineers in Sukhoi applied shielding to the GMV. (Something which people seem to be unaware about)

In the intake passage their is set special device, partially overlapping in the axial direction of the GMV preventing electromagnetic waves.

In addition to screening, this constructive solution separates inlet channel into several different cylindrical or planar voids, and, flat surface of the cavities can be both parallel and intersecting.

Such a complex segmentation and channel air intake cover wall segments with radar absorbing materials to reduce the power of the electromagnetic waves reflected from the GMV and from wall cavities, thus providing a decrease of the RCS in the forward hemisphere of the aircraft.

fullafterburner.weebly.com...

Edit to add:

There is also the possibility that the "N036L-1-01 L-band" arrays on the wing's leading edges use a similar method for EW jamming as the system masking the motors radar signature.

I bet there is a smaller more modular version of that system in the walls mitigating the motors RCS as part of their "smart skin" focus.

a reply to: tadaman

But if you look closely to those images available in the public domain, diagrams and photographs, it can be concluded that the inlet guide motor vehicle (GMV), or more simply - the first stage of the compressor to blades, it seems to be very clearly visible to enemy radar.  

Not really convinced that is the case because the geometry still looks wrong.

IF that quoted bit IS true, the guide vanes mentioned and visible are static and not moving. It's designed to impart direction to the flow before reaching the compressor stages for higher efficiencies. They aren't subject to a lot of heat and stress and are typically treated. It would also mean no radar blocker is currently fitted because the vanes are visible.

a reply to: RadioRobert

a reply to: Zaphod58

I've seen this described as a su-27++++++++(mockingly) or a su35 bodykit, thoughts on that? With the rcs reductions leaving alot to be desired, problems with al41f, the Indian pullout, and Russia's budget problems, is this basically dead in the water?

a reply to: Brainlet

No. Significantly reduced but not dead.