Yes radar pulses do reflect off solid surfaces, but all EM waves such as light or radar are reflected by any change in the density of the transparent material they are propagating thru, not just solid surfaces.
For example, almost all larger commercial jets have "clear air turbulence detection radar." The hot gases of the SU- 30's exhaust are in near pressure equilibrium with the surrounding air but much hotter, so their density is about half that of the surrounding. (Hot gases do expand and thus lower their density.) That density discontinuity is much greater (I would guess on the order of 80 times greater) than the clear air turbulence induced density change that is routinely detected by radars of commercial jets. Was that explanation, with illustration, clear enough for you to understand? Please correct your erroneous POV that radar only reflects off solid surfaces.
Certainly not anything like a simple command to lead the target by a fixed distance. Hell, even duck hunters don’t do that. I have seen simplified summaries of the SM -2 and HARM missile’s terminal guidance. (the full version is highly classified.) HARM’s is relatively simple as most of the time it can just home on the ground fire control radar, but if the enemy has two separately located units alternately operating on the same frequency there is the “centroiding problem.” HARM neatly solves that and some other defense attempts I cannot discuss.
SM -2’s terminal guidance is much more complex, despite it too is basically homing on the ship’s “illuminator” radar beam’s refection off the approaching threat. I.e. the ship “paints” the target but the target may weave and thus it current trajectory must be computed and projected ahead to mutual intercept point which need not be a perfect hit as you are correct there is a folded hoop of steel which expands and cut thru the target if the physical hit miss distance is not too great.
For your information, the Applied Physic Lab, where I worked for 30 years, invented all this, beginning in the closing years of WWII with the world’s first “proximity fuse.” That is how APL began now ~70 years of mainly saving the US Navy’s ships and designing the Aegis phased array radar, which scans 360 with no moving parts while simultaneously tracking and illuminating a large but classified number of approaching threats. So yes I know a little about all this, and I probably have forgotten much more than you know about both intercept calculations and warhead firing timing methods, which get to be very critical when ship’s defensive missile is traveling at several times the speed of sound to kill a target which is also approaching super sonically at the SM-2.
Those number came from my use of the sun to try to explain the concept of opacity to you; but you missed the whole point. If the plum is opaque to the IR wavelengths used by the attacking missile, then it will on receive radiation from then “skin depth” Just as we on Earth only receive radiation from the upper layers of the sun (one skin depth thick only) There are a lot of unknowns here, mainly the IR absorption characteristic of the plume and the wavelength the IR guidance detector is using. All I know for sure, from the OP’s video is that in the visible it was not possible to see thru the plume to the plane. I.e. it disappeared inside its own plume. This may, or may not be true in the IR range used by the detector. The USSR, obviously believed plane was hiding against IR detection also. – They put a lot of time and money into making this “hiding” maneuver possible.
That is correct. The exhaust leaving a jet engine is a thrust to the rear but even some commercial planes I have been on have what I think are called “claim shells” they can swing into the exhaust and redirect it forward. They are normally used on short runways to break faster than flaps alone can. – I have not seen the SU 30, “up close” but assume it has “claim shells” it can used to quickly stop forward motion ins basically level flight as appeared in the OP’s video. I don’t’ see any other way it could decelerate so quickly.
I will ignore rest of your posts, except to agree that the FA-22’s radar is probably so much better than the Su-30’s that the FA-22 may have fired a missile at the SU-30 before the SU-30 is even able to “see” the FA-22, but if there is a missile closing on you from several Km away in your SW direction, you know it did not get there by magic. If the “duck in plume until it passes” works and you survive, you know when will arrive and you can come out of the plume to look for a second attacking missile etc.
Again, I admit that I know little about modern air to air combat, I just know a little physic so I corrected you when you said jets work by pushing on the air or that only solids reflect radar, and here again tried to get you to understand that if a gas cloud is opaque, then you don’t see the hotter interior from the outside of it. I have no evidence that this is the case but the USSR spent a lot of time and effort making a plane capable of at least in the visible disappearing inside its own exhaust plume – It would be very strange that they failed to check the IR characteristic of the plume too. Common smoke is used to hid in by tanks etc.
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