J-10 Thread III (Closed to posting)

[Chaminuka]

deleted

 

[Quickie]

This statement makes no sense at all. Reducing radar reflection IS improving stealth. You're now twisting definitions so you don't have to admit that a DSI can be stealthy. Either that or I would have to question whether you even understand the concept of stealth. The fact is that a flat surface that reflects radar waves away from the emitter source is just as stealthy as a curved surface that reflects radar waves away from the emitter.

Typo error. I meant:

" My opinion is that the DSI intake's main function is to control inlet airflow at different speeds, and not to directly improve stealth by reducing radar reflection. (Woudn't having nothing in the way of the radar wave be the best option? - assuming no direct line of sight to the engine) "

You're now twisting definitions so you don't have to admit that a DSI can be stealthy. Either that or I would have to question whether you even understand the concept of stealth. The fact is that a flat surface that reflects radar waves away from the emitter source is just as stealthy as a curved surface that reflects radar waves away from the emitter.

Hint: Radar waves reflect diffusely, just like light (i.e. visible part of the EM spectrum).
Btw, you've no need to be in attack mode. I think I'll just stop here since we're out of topic.

What is the difference between a rounded surface and a curved surface?

Rounded as in part of a circle? Curve as in the shape of an aerofoil?

Okay, Stop! We're out of topic.

 

[Wolverine]

Woudn't having nothing in the way of the radar wave be the best option?

Doesn't matter if the radar wave doesn't return to the emitter.

Radar waves reflect diffusely, just like light (i.e. visible part of the EM spectrum).

Reflecting diffusely doesn't mean they reflect back to the emitter. You seriously need to look more closely at how the DSI is positioned and shaped on the aircraft. You also haven't answered why Lockheed would choose DSI for its other 5th generation STEALTH aircraft, the F-35.

Rounded as in part of a circle? Curve as in the shape of an aerofoil?

Why should that matter to you, if you are trying to claim that radar waves reflect "diffusely"?

 

[latenlazy]

Then, what's the use of the S-shaped inlet duct? Its purpose is to get the jet engine away from the line of sight through the air intake. i.e. to let the radar waves bypass the jet engine completely.

S-shaped inlets do perform that function, but radar is still bouncing around in an interior surface and getting amplified. It's not just the jet engine that generates a radar reflection, but the interior surfaces of the intake. When radar enters any interior structure it will reflect off of all the surfaces within that structure and generate a stronger return than if it just reflects off one surface. Anyways, the main point was that just because you have empty space where a DSI would be doesn't mean your radar return will be smaller. In fact depending on how you've shaped, coated, and designed the interior of the inlet, it could be bigger.

Sorry, I don't think I made such a claim in anyway.

You didn't. I was just trying to point out that even if there's an empty space where the DSI bump would be, the radar would eventually hit something anyways. In the case of an inlet, bouncing off an external structure it's much easier to control where the radar is reflected than an internal structure.

Not really rounded surfaces but very large curve surfaces.

I believe rounded and curved mean the same thing...

 

[Quickie]

Doesn't matter if the radar wave doesn't return to the emitter.


Reflecting diffusely doesn't mean they reflect back to the emitter. You seriously need to look more closely at how the DSI is positioned and shaped on the aircraft. You also haven't answered why Lockheed would choose DSI for its other 5th generation STEALTH aircraft, the F-35.


Why should that matter to you, if you are trying to claim that radar waves reflect "diffusely"?

Reflecting diffusely means all angles including back to the source. Of course, most of the wave energy is concentrated around the angle of incident/reflection.

 

[Quickie]

.....I believe rounded and curved mean the same thing...

A large curve surface looks more like a flat surface when viewed up close whereas a similar sized round surface would still look round when viewed up close.

I think I'll just stop here on this topic.

 

[latenlazy]

A large curve surface looks more like a flat surface when viewed up close whereas a similar sized round surface would still look round when viewed up close.

I think I'll just stop here on this topic.

You zoom in close enough to a "rounded" surface and it will look flat too (even a circle. Think of how the world thought the Earth was flat for the longest time). It's called the tangent.

 

[Wolverine]

Reflecting diffusely means all angles including back to the source. Of course, most of the wave energy is concentrated around the angle of incident/reflection.

You don't know what you're talking about.

 

[vesicles]

A large curve surface looks more like a flat surface when viewed up close whereas a similar sized round surface would still look round when viewed up close.

I think I'll just stop here on this topic.

In my opinion, a round surface IS a curved surface. Strictly speaking in the sense of geometry, a round surface is caused by curving a flat surface, thus a curved surface. ALL curved surface can form a circle. The rounder ones form smaller circles while the flatter ones form bigger circles. I think what you have in mind is the actual difference in the magnitude of curvature, which is determined by the radius of the curvature. Bigger the radius, bigger the angle and rounder the object looks.

 

[Quickie]

You don't know what you're talking about.

No, you don't understand. You should expect to see radar waves reflecting back at all angles including those back to the source, although more of the reflected wave energy is concentrated around the angle of incident/reflection. So, for each incident line you draw, there should be infinite reflected lines at all angles, although different in intensities.