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How did a 30 year-old Su-22 defeat a modern AIM-9X?

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Re: How did a 30 year-old Su-22 defeat a modern AIM-9X?

#31

Post by SAI_Peregrinus »

dingaling wrote: post #18
WalterBright wrote: post #6

I've often wondered if a WW1 stringbag could fly right past modern air defenses without being detected or tracked.

There was a team from a Large Defense Contractor at my local airfield recently with thermal-imaging equipment that seemed to be doing a good job of tracking light piston-engined aircraft, many of which are tube-and-fabric construction like WW1 machines. They wouldn't say what they were testing but it seemed fairly obvious. The whole engine block glowed hot as did the uppersides exposed to the Sun, let alone the exhau…

The engines also reflect radar quite nicely, even if the wood and fabric doesn't.

Re: How did a 30 year-old Su-22 defeat a modern AIM-9X?

#32

Post by angry_octet »

pavement wrote: post #2

Call it a hunch, but if the flares spew dirty and irregular, maybe there's an awareness that this sloppy spread of IR readings has benefits.

Usually you would want the flare to mimic the spectrum of your own engines. I don't know if by irregular they meant in spectrum or illumination level. There is not a lot of short term variation in a jet exhaust due to thermal mass and the need for thrust to keep maneuvering, but the aspect changes. So sensors are not assuming a straight tail chase.

I consider it much more likely that the Russians at some point obtained some AIM-9X seekers and tweaked their flares and/or engines to make it less effective.

The is also the concept of the 'war load' or 'war paint'. In normal operation planes will have their radar cross section increased and corner reflectors added, engine burn is tweaked, etc, anything that could be leaked or sensed remotely (when flying in international airspace, or from space, or covertly through radar backscatter). When you think things will get serious you pull out those chunks of superfluous steel, tweak the engine exhaust nozzle, load different firmware onto the missiles and the EW system. If actual combat occurs there may be different war-only RADAR wave forms.

Probably none of those are available to Syria (and the US has been building RADAR signatures of them for many months), except maybe an upgraded flare dispenser.

Re: How did a 30 year-old Su-22 defeat a modern AIM-9X?

#33

Post by madengr »

mannykannot wrote: post #24
WalterBright wrote: post #6

I've often wondered if a WW1 stringbag could fly right past modern air defenses without being detected or tracked.

I remember someone expressing surprise, years ago, that glass fiber gliders were detected by air traffic control radar. The most massive metal parts would be the undercarriage (single-wheel), but my guess is that the control cables, laid out in a cross at 90 degrees, would be the most reflective feature.

It doesn't take metal to reflect. Any change in dielectric constant causes a reflection, and that's amplified for any geometries that are multiples of 1/2 wavelength.

Re: How did a 30 year-old Su-22 defeat a modern AIM-9X?

#34

Post by mgamache »

digi_owl wrote: post #28
pavement wrote: post #2

Call it a hunch, but if the flares spew dirty and irregular, maybe there's an awareness that this sloppy spread of IR readings has benefits.

Would not surprise me. Soviet era designs and engineering seems to always having been more pragmatic, out of basic necessity.

The other way to read the article is to blame Soviet quality control. If we assume the variation in burn is random, it may mean overall better protection of your airborne resources, but you could not assess the protection of any individual aircraft. That sounds Soviet to me.

Re: How did a 30 year-old Su-22 defeat a modern AIM-9X?

#35

Post by semi-extrinsic »

WalterBright wrote: post #6

I've often wondered if a WW1 stringbag could fly right past modern air defenses without being detected or tracked.

Not just with airplanes! See the Millennium Challenge 2002 naval exercise:

https://en.wikipedia.org/wiki/Millennium_Challenge_2002

TL;DR: the Red team general, with Iran-equivalent forces at disposal, employed asymmetric tactics and WW2 equipment to sink an aircraft carrier, ten cruisers and five amphibious landing ships, estimated loss of 20 000 US military personell. Then they stopped the exercise because it was too embarrasing, refloated the Blue team ships and instructed the Red team to play by the instructions designed to make them lose.

Re: How did a 30 year-old Su-22 defeat a modern AIM-9X?

#36

Post by _e »

pavement wrote: post #2

Call it a hunch, but if the flares spew dirty and irregular, maybe there's an awareness that this sloppy spread of IR readings has benefits.

Interesting. Sloppy is random is simple is robust.

This reminds me of a story where the USA got its hands on a new MiG and when they opened it up found that it used some kind of antiquated technology. Some time later the USA found out that this was intentional because the older tech could withstand nuclear radiation whereas the new tech would instantly fail.

Re: How did a 30 year-old Su-22 defeat a modern AIM-9X?

#38

Post by rjsw »

digi_owl wrote: post #29
Stranger43 wrote: post #23

Earlier quoted context omitted.

There were some incidents doing WWII where both the British and soviet ran successful raids using low and slow flying biplanes that was simply too low and slow for the motors guiding the anti aircraft guns of the day. Doing the Taranto raid the low altitude of the Swordfish bombers caused the Italian navy to not just miss the planes but inflict collateral damage on themselves. Today it's much harder to pull a similar…

The same thing, combined with daredevil pilots (or in this instance, navigator), enabled the Bismarck sinking. Basically the Bismarck AA guns either had problem tracking them, or the ammo didn't do much. And the torpedo that hit the Bismarck rudder was fired in part by the plane's navigator hanging over the side of the aircraft, and telling the pilot when to release to avoid the waves.

The Swordfish wasn't totally low-tech, they were equipped with radar which allowed them to find the Bismark at night and find their own carrier again afterwards.

Re: How did a 30 year-old Su-22 defeat a modern AIM-9X?

#39

Post by mannykannot »

madengr wrote: post #33
mannykannot wrote: post #24

Earlier quoted context omitted.

I remember someone expressing surprise, years ago, that glass fiber gliders were detected by air traffic control radar. The most massive metal parts would be the undercarriage (single-wheel), but my guess is that the control cables, laid out in a cross at 90 degrees, would be the most reflective feature.

It doesn't take metal to reflect. Any change in dielectric constant causes a reflection, and that's amplified for any geometries that are multiples of 1/2 wavelength.

Indeed, but it is a matter of degree - glass fibre seems to be a common material for radomes. I made a cursory search for relevant figures, but didn't come up with specific figures.
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