• Hi Guest! Forum rules have been updated. All users please read here.

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

yahya

CLEARANCE: Restricted
Joined
Apr 2, 2020
Messages
28
Reaction score
7
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.
 

Lc89

CLEARANCE: Confidential
Joined
Aug 10, 2019
Messages
91
Reaction score
29
Lack of allied EW aircraft in the area
 
Last edited:

Evgeniy

CLEARANCE: Restricted
Joined
Mar 30, 2020
Messages
31
Reaction score
18
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.
 

_Del_

I really should change my personal text
Joined
Jan 4, 2012
Messages
430
Reaction score
73
And lazy/complacent mission planning
 

Ronny

CLEARANCE: Secret
Joined
Jul 20, 2019
Messages
239
Reaction score
95
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:
 

overscan (PaulMM)

Administrator
Staff member
Joined
Dec 27, 2005
Messages
11,990
Reaction score
2,161
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.
 

GARGEAN

CLEARANCE: Secret
Joined
May 7, 2018
Messages
346
Reaction score
86
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.
 

overscan (PaulMM)

Administrator
Staff member
Joined
Dec 27, 2005
Messages
11,990
Reaction score
2,161
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.
 

Hobbes

CLEARANCE: Top Secret
Senior Member
Joined
May 9, 2008
Messages
785
Reaction score
148
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.
 

Foo Fighter

I came, I saw, I drank some tea (and had a bun).
Joined
Jul 19, 2016
Messages
1,261
Reaction score
334
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.
 

sferrin

CLEARANCE: Above Top Secret
Senior Member
Joined
Jun 3, 2011
Messages
12,896
Reaction score
969
Even Frank Burns was able to shoot down 5 o'clock Charlie.
 

Grey Havoc

The path not taken.
Senior Member
Joined
Oct 9, 2009
Messages
10,887
Reaction score
1,240
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).
 

riggerrob

I really should change my personal text
Joined
Mar 11, 2012
Messages
711
Reaction score
279
Wet airframes reflect more radar signals.
 

Foo Fighter

I came, I saw, I drank some tea (and had a bun).
Joined
Jul 19, 2016
Messages
1,261
Reaction score
334
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.
 

DWG

CLEARANCE: Top Secret
Joined
Feb 11, 2007
Messages
623
Reaction score
317
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.
 

yahya

CLEARANCE: Restricted
Joined
Apr 2, 2020
Messages
28
Reaction score
7
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?
 

_Del_

I really should change my personal text
Joined
Jan 4, 2012
Messages
430
Reaction score
73
Seems likely that classical Antagonists would have seized the opportunity and widely promoted the news.
 

VTOLicious

CLEARANCE: Top Secret
Joined
Nov 24, 2008
Messages
646
Reaction score
238
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?
 

Grey Havoc

The path not taken.
Senior Member
Joined
Oct 9, 2009
Messages
10,887
Reaction score
1,240
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.
 

LVisingr

CLEARANCE: Restricted
Joined
May 11, 2007
Messages
34
Reaction score
21
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.
 

yahya

CLEARANCE: Restricted
Joined
Apr 2, 2020
Messages
28
Reaction score
7
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?
 
Last edited:
Top