How F-117 was shot down in 1999 by an SA-3 battery?

yahya

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Dear Colleagues, although this subject appeared in numerous discussions and publications, can you explain to a layman how an SNR-125 Low Blow managed to get a lock on an F-117 and to shoot it down on 27 March 1999? Can this kind of radar operating on the I/D band indeed lock on a stealth plane? I can understand that a P-18 Spoon Rest operating on VHF could detect a stealth plane from distance, albeit with mixed accuracy, especially back in 1999, but what about the SNR-125? Or was another detection method used like the LLTV? This site mentioned Serbian modifications and upgrades to the original SNR-125, however it remains unknown if they were applied before the events of 1999. Any comments appreciated.
 
Lack of allied EW aircraft in the area
 
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Apparently the effective reflective surface of the F-117 was not as low as it is usually considered to be. Plus the lack of cover from electronic warfare aircraft.
The version about the "open hatch", in my opinion, is absolutely far-fetched.
Sometimes, everything can be much simpler than it seems.
 
Dear Colleagues, although this subject appeared in numerous discussions and publications, can you explain to a layman how an SNR-125 Low Blow managed to get a lock on an F-117 and to shoot it down on 27 March 1999? Can this kind of radar operating on the I/D band indeed lock on a stealth plane? I can understand that a P-18 Spoon Rest operating on VHF could detect a stealth plane from distance, albeit with mixed accuracy, especially back in 1999, but what about the SNR-125? Or was another detection method used like the LLTV? This site mentioned Serbian modifications and upgrades to the original SNR-125, however it remains unknown if they were applied before the events of 1999. Any comments appreciated.
Best lecture on the subject:
 
Wikipedia has a good summary of the official account by Zoltan Dani who is the actual commander of the SA-3 battery.

According to him, their low frequency P-18 radar was able to detect the F-117 at 25km, which seems plausible. They then tried to acquire it with the SNV-125 fire control radar (cued to the target by the P-18) twice for 20 seconds on each attempt, turning the radar off between. They then tried again, for a third time, and successfully detected the F-117 at 13km distance, locked on and fired the missile.

SNV-125 works at 9GHz (I band) for tracking with a D band missile guidance channel.
 
Spotting because of bomb bay door is quite a meme. Not time nor signature change of that are not enough to provide previously undetectable aircraft with solid fire solution.
 
So, there are a few things to consider.

1) The VHF P-18 is one of the better radars to try to find an F-117A with. It is likely to have a greater range than higher frequency radars, but be relatively inaccurate.
2) The S-125 is command guided, which means that the missile doesn't need to acquire the target itself, only the SNR-125 control unit does.
3) The missile is quite large, with a powerful warhead (72kg), and typically two are fired at a single target.
4) The SNR-125M had added TV channel for target acquisition in case of radar jamming.
5) Supposedly some Yugoslavian radars were upgraded to SNR-125M1T standard with thermal cameras and laser rangefinders.
6) The F-117 aircraft flew predictable paths and failed to avoid the SAM battery. Even with a stealth aircraft you don't want fly directly at SAM batteries.
 
Spotting because of bomb bay door is quite a meme. Not time nor signature change of that are not enough to provide previously undetectable aircraft with solid fire solution.

I disagree. The signature change from a closed bomb bay (covered by a door designed for signature reduction) to an open one (no signature-reduction features inside, instead a mess of reflecting surfaces) would be significant.
 
Is it possible that an aspect change allowed the belly of the aircraft to be the reflective surface? As far as I can recall the belly of the aircraft is pretty flat.
 
I'm surprised this issue has popped up again. It was confirmed by subsequent investigations within NATO that the Serbian success was down to a combination of espionage (a NATO officer gave information on mission routes and timings to the Serbs) and serious complacency on the part of mission planners (they kept using the same route over and over again, despite complaints from the pilots and others).
 
Even Frank Burns was able to shoot down 5 o'clock Charlie.

Actually, the only thing Frank Burns shot down was the ammo dump. Jolly good show ol' chap, top hole in one to him.
 
6) The F-117 aircraft flew predictable paths and failed to avoid the SAM battery. Even with a stealth aircraft you don't want fly directly at SAM batteries.

They're called flak traps for a reason!

See also the attack on Karbala in 2003 for the inadvisability of flying into a waiting flak trap.
 
Colleagues, thank you for your input. I watched the film that Ronny referred to. (Thank you Ronny for the link.) Mr Dani mentioned in it that their P-18 worked on the lowest frequency of 140 MHz which he named the 'L-1,' streamlining the detection of the F-117, and that the information from the P-18 went to -- I assume -- the SNR-125, to its TV monitor, which suggests that the tracking method might have been other than a radar. overscan (PaulMM) mentioned the SNR-125's TV capability. (Thank you overscan (PaulMM) for the important comments.) At 22:01 of the film starring Mr Dani, he mentioned: "on our manual targeting screen, it was very clearly shown". The F-117 was downed after 8pm, so I assume it happened in complete darkness, which would be in line with the F-117 tactics. While we do not know if the SNR-125 in place was equipped with a night vision tracking camera instead of the standard daylight camera the original kits were sold with, does this mean that the lock was indeed obtained through the SNR-125 radar, which could pump out, as far I remember, about 0.2MW of RF power, or even more? Assuming that the F-117 indeed was visible to such a beam at 13 km, what eventually could be the source for missile CLOS data: the radar or a thermal camera? Also, how Mr Dani could have determined with such a precision that the F-117 was 13 km away from their S-125 battery?
 

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Seems likely that classical Antagonists would have seized the opportunity and widely promoted the news.
 
It's actually the first time I hear that claim. I'm wondering why he's making such a bold statement and presenting it like common knowledge.

Is there any evidence to support that?
 
Here's a 3 page brochure put out by Yugoimport (before the shoot-down) describing their proposed upgrade.
 

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To play Devil's Advocate for a moment, there have been rumors over the years that a few incomplete B-2 airframes were diverted into a classified program.
 
Several unofficial sources claim thet there were actually two F-117s hit by Serbian SAMs, but the other one managed to get back to the base. However, it was seriously damaged (reportedly, it lost half of its V-tail), thus, it was never repaired and later was scrapped.
 
Thank you Searay for this interesting document!
Here's a 3 page brochure put out by Yugoimport (before the shoot-down) describing their proposed upgrade.

If the modification described in it was indeed implemented before the events of March 1999, we can now assume that Serbian military were fully aware of possible difficulties in using obsolete radars in the SAM fire control systems in modern battlefield. Mr Dani mentioned in his presentation in the film listed above the alleged plot of 1981 to disassemble Yugoslavia, so they had enough time to get prepared. Hence, they relied on thermal imagery at the missile guidance stations, which indicates that at night the target could be passively tracked by an EO unit rather than by the SNR-125 radar, while range data was provided by a laser range finder unless the "three-point guidance method" discussed in the cited document was applied. This makes sense. I assume that on that very day it was not raining, and the EO tracker was used to provide coordinates relayed to the missiles that were launched.

It seems that many contemporary upgrade packages of the old Soviet-era anti aircraft systems employ modern EO tracking sets with laser rangefinders. So, the main vulnerability of such systems consists of the CLOS datalink, which could be jammed, albeit by applying extremely high RF power signals, as the Soviets were known to employ very high power in their CLOS missile datalinks.

To sum up the discussion, can anyone add something on the "three-point guidance method" mentioned in the document posted by Searay?
 
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So, there are a few things to consider.

1) The VHF P-18 is one of the better radars to try to find an F-117A with. It is likely to have a greater range than higher frequency radars, but be relatively inaccurate.
2) The S-125 is command guided, which means that the missile doesn't need to acquire the target itself, only the SNR-125 control unit does.
3) The missile is quite large, with a powerful warhead (72kg), and typically two are fired at a single target.
4) The SNR-125M had added TV channel for target acquisition in case of radar jamming.
5) Supposedly some Yugoslavian radars were upgraded to SNR-125M1T standard with thermal cameras and laser rangefinders.
6) The F-117 aircraft flew predictable paths and failed to avoid the SAM battery. Even with a stealth aircraft you don't want fly directly at SAM batteries.
Unless your target is said SAM site.

I never did understand why the F-117 wasn't used as a Wild Weasel...

Is it possible that an aspect change allowed the belly of the aircraft to be the reflective surface? As far as I can recall the belly of the aircraft is pretty flat.
My understanding was that this happened when a big turn put the bottom of the F-117 more or less perpendicular to the the SAM site, night after night because the idiots kept reusing the same routes. And that would make a huge bloom in RCS saying "there's something sneaky here!"
 
Because:
1- It doesn't even have RWR
2- HARM can't fit inside F-117 weapon bay
Don't have to use HARM to smite a SAM site, folks were using CBUs and even dumb bombs in Vietnam. A HARM just makes it easier to catch a SAM site before they can get a missile launched at you.
 
Don't have to use HARM to smite a SAM site, folks were using CBUs and even dumb bombs in Vietnam. A HARM just makes it easier to catch a SAM site before they can get a missile launched at you.
when they use bombs, they need to approach the site at low altitude. At that point, why bother with stealth aircraft?
 
when they use bombs, they need to approach the site at low altitude. At that point, why bother with stealth aircraft?
Because a stealth plane can approach at mid to high altitude with LGBs? Or today with JDAMs or WCMDs.
 
Because:
1- It doesn't even have RWR
2- HARM can't fit inside F-117 weapon bay

Plus it's hard to bait the SAMs if you have a low head-on RCS.

That said, F-117s have been used for pre-planned strikes on IADS targets, (especially radars and command centers) just not for the on-the-fly sort of strikes that usually characterize Wild Weasel. (More DEAD than SEAD.)
 
Plus it's hard to bait the SAMs if you have a low head-on RCS.

That said, F-117s have been used for pre-planned strikes on IADS targets, (especially radars and command centers) just not for the on-the-fly sort of strikes that usually characterize Wild Weasel. (More DEAD than SEAD.)
Granted, a Nighthawk wouldn't do much SAM baiting, I was thinking more along the lines of a point man waiting to smite a radar or SAM site once revealed. Basically a really expensive loitering munition.

Related: can a Nighthawk carry more than one weapon per bay? Like some 500lb bombs on triple racks?
 
Related: can a Nighthawk carry more than one weapon per bay? Like some 500lb bombs on triple racks?

Nope. The bay is built around a pair of trapeze to lower the weapons into the slipstream, so there's really only one suspension point on each side. And each side of the bay is sized to just barely hold a single GBU-27 (2000-lb Paveway with folding fins). By my math, that bomb is just a hair under 20 inches wide (28 inches across on the diagonal). A Mk 82 (clean, no guidance kit) is 10.7 inches. So you can't fit two across in the bay, even if you replaced the trapeze with some sort of multiple rack.

If the F-117 had stayed operational to the present, maybe it could fit SDBs, but why use a silver-bullet stealth aircraft to deliver glide bombs from standoff range?
 
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