14 August 2012

Fuel-air bombs? Evidence from Talbiseh

ODAB-500: Fuel air bomb, vacuum bomb, sometimes called thermobaric weapon. Video sources from Syria analysed. Russian origin.
(safety section added and also some editing December 09, 2012) 

Please notice: this is a layman's post. If you read it please don't skip the notes during and at the bottom of the post. Also before you decide what to think of my writings: please read through my latest post (plead added 03/06/2014).

On August 6th a series of videos were uploaded to talbisah's YouTube channel. They were said to be from the town Talbiseh between Homs and Rastan in Central Western Syria. Especially one of the videos in which two falling bombs can be seen got a lot of attention in the days after(see note 1). It was @felimmcmahon from Storyful who brought the videos to my attention, and I have been trying to look into what kind of bombs might have been used here.

Left frame: the first bomb that fell. Right frame: the second bomb. Image source: video uploaded to talbisah's YouTube Channel 06/08/2012.

the vertical lines mark where the bombs fell. Source: same video as above, uploaded to talbisah's YouTube Channel 06/08/2012

To be able to compare the impact positions with the blast, I have marked the paths of the two bombs with vertical lines (images above), and from that study it appears, that the main blast comes from where the bomb to the left hit. This makes me think that possibly the other bomb didn't detonate as intended.

Some of those who have seen the video
have suggested that the bombs are slowed down by some kind of parachute. It is also being suggested that the bombs are so called fuel-air bombs (or vacuum bombs). From what I've read fuel-air bombs works by first spraying its explosive liquid (fuel) into the air at the target area, and then igniting it. This causes an explosion that doesn't have the initial intensity of "usual" high explosive filled bombs, but the sprayed fuel has a much larger volume when it ignites, and since it uses oxygen from the surrounding air to burn explosively, the overall effect of fuel-air bombs is larger than high explosive filled bombs of the same weight (see note 2). 

I do not have the information as to how this particular model sprays its fuel, but the spraying is often done by an explosive charge placed in the central axis tube of the bomb. The ignition will typically be timed to be activated some 0.15 sec after the burst charge has dispersed the fuel (added 09/12/2012).

The images below are from a video that in my understanding should be showing the damages of the attack seen in the previous frames. I have not been able to document this, but for several reasons I find this source credible. Also since I find it documented that the video is from a war-zone, and unlikely not to be from Syria, then, even if the video should turn out not to be from Talbiseh, studying the object in the image  below seems relevant.

a frame from this video upoladed to talbisah's YouTube Channel 06/08/2012.

The object in the frame above appears to have crashed through the reinforced concrete roof  before crashing on the floor of the room. This would be consistent with being dropped from an aerial vehicle, and also with being the one of the two bombs that didn't explode.

Assuming it is a bomb; when comparing it to free fall fragmentation bombs like the OFAB 250-270 the tail looks different. The tail on this object looks like a large tube, and what I believe to be one of the fins can be seen to the left in the left frame below. The main body of the bomb also seems to have walls that are much thinner that the OFABs.

three frames from the same video as above, uploaded to talbisah's YouTube Channel 06/08/2012.

All those differences and the hollow main body of the object first made me think of a canister for cluster bombs, but that does not seem to be the case. Instead, as mentioned earlier, fuel air bombs were suggested. And when a particular model of these was pointed to as a possibility the details started to fit. The model is called ODAB-500 and can be seen in the images below.
By comparison to the video frames its overall size looks right. The tail looks right too (and the reason for it being built around the large tube is that is contains a small parachute). Also the nose has the right shape, and when looking closer it also has the same kind of metal band around the foot of the nose.

I'm not sure what the black component in the centre frame above is - or if it's even from the (supposed) bomb, but the hollow space and the thin walls of the main body (behind the black component) corresponds with the ODAB-500 too.


mage and drawing of an ODAB-500. Image sources: Left: Wikipedia commons. Right: image posted on valka.cz. Thanks to @Jugend75 for mentioning the ODAB-500 as a possibility. * note of 17/08/2012: from what I read there are two models of ODAB-500: an ODAB-500PM and an ODAB-500PMV. In this illustration the model to the left (as I understand it) is an ODAB-500PMV with the fins of the tail exceeding the diameter of the "tail-metal-band". The drawing to the right could look like being of an ODAB-500PM with the fins circumscribed by the "tail-metal-band". The two models seems to be compared on this page.

All in all I find this a quite convincing match. The uncertainty that remains relates to the fact that the match is made on the basis of an unverified video. I'll leave it to the readers to decide on whether or not to find it credible.

Finally a little extra detail: later in the video, with the supposed unexploded ODAB-500, some metal fragments are shown (outside in the street). These fragments could look like being from an OFAB bomb(see note 3). If that is the case they could very well be from an earlier attack, but never the less I feel like quoting something that was mentioned by Vadim Naninets (aka @Jugend75):

"during Soviet war in Afghanistan ODAB-500 were reported as one of the most unreliable munitions - due to fuze failure only 15 - 50 % of the bombs dropped detonated. Thus, the typical method was to combine dropping of 3 ODAB-500 with 1 HE bomb like FAB-250 or FAB-500 - just to secure combustion of ODABs air fuel mix. Sometimes the following plane launched several S-8 unguided rockets at ODABs impact area with the same purpose - just to secure combustion." (Vadim Naninets has told me that his source for this information is a book by Victor Markovsky with the title "Hot skies of Afghanistan")
But so fare that is only a thought.

Video uploaded August 16: A collection of ordnance fragments in Tabliseh. Among many other types of expended munitions there is one that looks like from an ODAB-500.

three frames from video uploaded to talbisah's YouTube channel on 16/08/2012. (link via @HamaEcho). - to study details use zoom (cmd +) after clicking the image.

It could be the same as in the video uploaded on August 6th, but notice the compartmentalization of the room of the main body (centre frame). In the August 6th video it looks like the dividers have moved to the front, but I can not exclude that they have been moved back in position before being put on display for this new video.

But whether or not this is of the same bomb, this video makes it possible to - in part - find an explanation for the component in the centre frame three images up. It can be seen that it is originally placed somewhere inside the tail-tube (right frame above), and I assume its purpose is to in some way take part in the spraying or/and igniting of the explosive fluid of the bomb.
What can also be seen is some kind of electronic installation in the nose of the bomb (left frame). This could be for controlling and timing the spraying and the following ignition. (section expanded 04/09/2012 and some change made 09/12/2012). 

Update August 16:
A series of tweets by ‪ seems to be relevant to this post:‬

‪@HamaEcho: ‬Massive bomb landed on Jabal Shahshabo, ‪‬ ‪‬ Plain fields shelled heavily for months now, for no reason. ‪#Syria‬ (3:32 PM - 16 Aug 12)
@HamaEcho: The bombs are dropped on the fields not the villages for some reason, it's also the first area where cluster bombs were used. (3:38 PM - 16 Aug 12)
@HamaEcho‬: ‪ I think it's just for testing before these weapons are used in other areas, but why don't these f****** use empty land? (3:43 PM - 16 Aug 12)

I have taken some frames from the linked-to video: 
three frames from video uploaded to ابو رشيد 's YouTube channel 16/08/2012.

This seemingly unexploded bomb in many ways resembles the one reported from Tabliseh, but I actually get the impression this one is of a larger model. Therefore I have made a quick search, and in this document there is a mentioning of both an ODAB-750 and an ODAB-1100(mistake!: see note 4).
I consider it a possibility that what is shown in the video is from one of these larger sizes. If so, that could be the reason for having to make tests or practice at this time(see note 5).

But - larger or not - in the frame above to the right, a component can be seen in the upper left corner. I believe this is the same type of component, that I, in relation to the August 16th video, suggest, as having to do with spraying and/or igniting of the explosive fluid. (section expanded 04/09/2012, some change made 09/12/2012).


Update August 21:
A video uploaded August 20th: this video shows an object that could - as the title says - be a thermobaric rocket. The video is blurred, and there is no objects in the frame that I am able to use as measure-references, but I will estimate the diameter of the object to be around 20 centimetres. This could make it a 220 mm rocket for the TOS-1 Buratino multiple rocket launcher. Or something similar.

* comment: the video linked to in this section has been removed by the uploader. But to clarify: this was a big maybe, and since this report, I have seen no cases of rockets larger than grads (except a more recent mentioning of a
333 mm maybe-Iranian system). At the time, someone thought the object, claimed-to-be a rocket, was instead a helicopter fuel tank, which had been dropped. The shape - In my view - didn't quite match, but the possibility, that something was being mistaken for a weapon should also be included) (comment added 04/12/2012).

Update October 19 - November 25:
Left: releashing flares. Centre: bomb dropped (bottom of frame). Right: the falling bomb. image source: video originally uploaded to SHAMSNN's YouTube channel 17/10/2012.

A video of an aerial attack: an Su-22 attack jet looks like it's releashing flares as it drops a bomb. The bomb looks like a parachute retarded bomb. The explosion is for the main part covered by bushes, but the flash could resemble what is seen in the video from Talbiseh.
* note: this video has since been taken down.

Video uploade September 15: fragments at 0:40 matches ODAB fragments. Location is stated as Bashqatin, about 12 km West of Aleppo (link via @Brown_Moses, added 06/11/2012). 

Another video uploaded October 17: fragments that resembles those of an ODAB-500. The title states the location as Kafr Sejena in Idlib (link via @JMiller, added 30/10/2012). 

Video uploaded October 30: remnants of an ODAB. The title states the location as Deir Ez-Zour, and from sampling the YouTube channel it is uploaded to it seems that the channel is based in that city. (link via @Brown_Moses, added 06/11/2012). 

Photo of an unexploded ODAB-500: according to the source the location is Aleppo. Date is unknown. (added 06/11/2012). 

Remnants of an ODAB including of the parachute: according to the title the location is Taftanaz, Idlib. Uploaded November 7, 2012.(link via @Brown_Moses). 

Remnants of the body of an ODAB: according to title the location is Deir Ez-Zour. Uploaded October 31, 2012.

More remnants of ODABs: remains of an ODAB, laying in a room. Seemingly entered through the roof. The location mentioned in the title is Deir Ez-Zour and the upload date is November 21, 2012.

An ODAB-500 being dropped by a MiG-23: according to the video title at Darayya - a Southern Damascus suburb - on November 30, 2012.

A thought maybe-to-be a case of multiple ODABs*: Krak des Chevaliers, Homs. Videos uploaded January 4, 2013.
* note: by March 2013, I find it more likely, that the bombs used in this attack was something different than fuel-air bombs.
..

- Caution: several of the munitions in these videos are UXOs (unexploded ordnance). This means that they still contains explosives which makes it very dangerous to handle them, and this should only be done by professionals. Therefore please notice the ARMS guidelines: 

- Avoid the area 
- Record all relevant information 
- Mark the area to warn others 
- Seek assistance from the relevant authorities

- Specific warning about fuel-air bombs: even if these bombs are broken and the fuel have leaked, they can still hold a deadly bursting charge as well as one or more ignition charges. Handling remains of these bombs - as seen in some of the videos of this post - is potentially lethal, and should be avoided.
The fuel if leaked or leaking also represents potential healths hazards both due to being flammable and due to unknown level of toxicology. These are additional reasons to stay away from these bombs, to avoid contact with the fuel and to avoid smoking or other use of fire anywhere near them. 

The above warnings are to give an idea of the kind of dangers these bombs represent, if you should ever happen to encounter one yourself, or if you should be contacted by someone who has, please seek more guidance. Also see the below links:

- Download-link for Technical Note for Mine Action (pdf-file)
- link to print-out warning flags in English and Arabic from R.R.M.A.

..

* note 1: I refer to the falling objects as bombs, but this is not absolutely certain. Theoretically the video could be manipulated or the explosion that occurs as the second falling object hits could be from something else.
* note 2: the term "thermobaric" is often used to describe fuel-air bombs. But thermobaric bombs/warheads does not work in the same way as fuel-air bombs. By comparison the fuel-air bombs have their fuel spreading for a longer time before igniting it. The term "vacuum bomb" is also sometimes used. From what I've read, this term should fit better with the characteristics of the fuel-air bomb than with thermobaric weapons. This note was put in when I corrected the section of the text to match this fuel-air/thermobaric destinction (added 09/12/2012).
* note 3: after re-viewing the video material I find it less likely that the fragments shown in the street are from an OFAB bomb (but still, the information about the (un-)reliability of the ODAB-500 remains relevant to getting an idea of what kind of a weapon that might have been used here)(added 15/08/2012).
* note 4: after having looked for more information of ODABs larger than the ODAB-500, I have become uncertain if my reading of the linked to passage (that mention ODAB-750 and ODAB-1100) is correct, and I have found no other mentioning. Therefore the linked-to text can not be taken as a confirmation of my impressions. However, given the reported history, I still find the testing/practice thesis likely, but I'll not try to come up with other reasons as to why this could be the case here(added 17/08/2012).
* note 5: the tail fins of this model too exceed the diameter of the metal band of the tail, which - if it is a 500 kg model - in my understanding will make it an ODAB-500PMV(added 20/08/2012).

* general note: this is not an expert analysis, rather it's a presentation of primarily visual observations. Please apply you own judgement.


related posts on this blog:
-
Syrian Airforce Unleashed
-
Syrian airforce use of the L-39 Albartos
- Hama
- Rastan
- weapons used on Homs
- mortar position, Homs
- Syria: Local photo sources

The latest on Twitter: search 'Fuel-air bombs'. search 'Thermobaric'.

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NB: since January 2013 there have been a number of video-reports showing jets dropping parachute retarded bombs, that I suspect to be of a different type. However, I have not seen any identification of the bombs used in these cases. The case from Krak des Chevalier linked to further up could belong to this group (added april 10, 2013).
By April 14, 2013, a post on Brown Moses blog looks at some possible models.
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- all comments and corrections are welcome - either as comments here or @ my twitter acount.

9 August 2012

Objects almost hitting a Syrian L-39


Please notice: this is a layman's post. If you read it please don't skip the notes at the bottom of the post. Also before you decide what to think of my writings: please read through my latest post (plead added 03/06/2014).


In my previous post "Syrian Air-force use of the L-39 Albatros" I finally decided to highlight a recent video showing a clear maybe-bomb drop. The drop occurs at 0:06 min. in the video, and in order to get as much detail as possible for my screen-grabs I chose the highest resolution, switched to full screen view, started the video....and got a surprise:

At 0:02 min. and again at 0:03 min. an object can be seen descending from right to left, and especially the first seems to pass quite close by the plane.
As mentioned this was a bit of a surprise, and I'm uncertain if it has any significance. Therefore I have made an image of each sequence which can be seen below. The images are made by overlaying four frames with the plane in a fixed position, and in both images the view of the plane is from the third frame.
Since the plane moves some distance within that short period, this will not be an absolute accurate depiction, but I think it works to bring attention to what happens.

First occurrence:
Four frames overlaid to show descending object at 0:02 min in video uploaded 07/08/2012 to AENNetwork's YouTube channel
video no longer available, sorry.

Second occurrence:

Four frames overlaid to show descending object at 0:03 min in video uploaded 07/08/2012 to AENNetwork's YouTube channel
video no longer available, sorry..

Given the closeness to the plane, my immediate thought was, that what can be seen, is something being fired at the plane. But at the same time it obvious, that what ever object it is, that is passing, it would have to be either on the descending part of an arch (if fired from the ground) or to have been fired/launched from a position above the plane.
...or are there more alternatives?

One possibility would then be that what passes are incoming artillery shells. But would it be thinkable to have a plane flying around over an area while it is being shelled?

Another possibility that I can think of is something being fired from another aerial vehicle. That thought, however, requires things like an anti government plane (or drone?). An interesting thought, but with my limited knowledge - and without touching the political implications of such a scenario - I would expect an air-to-air missile to leave a trail of smoke from the motor. I would also think that such a missile would be guided in some way, which, I believe, would result in different looking paths for the objects(?).

It would be interesting to get some opinions on this.

Update, October 8:

This TwitLonger list contains 19 video-reports of an attak on Kafr Nabl. Several of these recordings are of rockets fired from jets. There is some visuel resemblance to the video highlighted in this post, but I don't find it conclusive. The videos are uploaded on September 27th, and the titles indicate, that the attack took place on that date too.
(the mentioned list is by 2026-01-02 no longer available where it when this post was written)
..

* note: at least in theory this video could be manipulated. Also the objects that I keep seeing as some kind of shell or missile can be something completely different.

- all comments and corrections are welcome - either as post-comments here or @bjoernen_hj.

5 August 2012

Syrian Airforce use of the L-39 Albatros


Please notice: this is a layman's post. If you read it please don't skip the notes during and at the bottom of the post. Also before you decide what to think of my writings: please read through my latest post (plead added 03/06/2014).

frame at 0:18 min. from video uploaded 28/07/2012 to UnionOfAleppo's YouTube channel.

(latest updated: February 13, 2013, except for the plead above).
For a long time the Syrian government seems to have been avoiding using fixed wing aircrafts in its fight against opposition forces. One can only speculate what the reason for this might have been, but a wish to make an internationally imposed no fly zone irrelevant seems an obvious possibility.
If that thought holds, then helicopters appears to have been deemed less problematic, and an increased use of these have been seen - escalating from firing heavy machine guns and S-5 rockets to dropping 250 kg unguided free fall bombs (OFAB 250-270). The first cases of use of OFABs were video reported from an area West of Hama at the end of June. Over a period of one or two weeks a series of large craters and unexploded bombs were video-reported from that area. The pattern of the first reports seemed to be that the bombs were dropped in pairs and with no apparent target. The (single) case of attempted use of cluster munitions reported on July 10. was also from that area, and the lack of targets lead to speculations that the area was being used for practice.
Since then there have been several recordings of Mil Mi 25 (Hind-D) helicopters dropping large bombs at a number of other places. One was recorded bombing Talbiseh (Homs), an unexploded OFAB 250-270 was recorded in Deir Ez-Zour, and a resent recording of a Mil Mi 25 dropping two bombs was made in Daraa (to mention a few).


Map of Syria with the cities mentioned above. The red line is the M5 highway. Map stitched together from screen shots from Google Maps.

But for what ever reason; this non-deployment of jets - if it ever existed - has now been ended: On July 23. reports started coming from Rastan that the city was being bombed by MiG-23s. The identification of the planes were reported via Twitter and said to have been made by defectors. A number of videos in my view make it likely, that jets were being used to drop bombs there, but no material has come out that can be used to make a visual identification of the planes used.

Then, two or three days later, the first recordings of fixed wing planes being used against opposition forces in Aleppo too started to come out. All of these recordings show planes with a shape that matches the L-39 Albatros. Reports from Aleppo has mentioned the MiG-21 too, but with no documentation.


Whether or not MiG 23s were the planes used against Rastan still remains uncertain, but until recently the way the L-39s were deployed at and around Aleppo seemed to be different from what Rastan had been subjected to(note 1).

According to Wikipedia, the L-39 was designed in Czechoslovakia in the late 1960's, primarily as a trainer jet for the Warsawa pact countries. It has a maximum speed of 750 km/hour (sub-sonic) and a range of 1,100 km (1,750 km when using external fuel tanks).
Given that the L-39 is designed for lower speeds compared to typical fighter jets, it has qualities, that matches well with a role as a light ground attack jet - especially against an enemy with little anti aircraft capacity. And as the design of the L-39 has been updated the ability to take on that role has been increased (section added 27/09/2012).

Auto-cannon and rockets:
Left: Muzzle flashes, frame from a video that has since been taken down, but similar recording can be seen here. Centre: Muzzle flashes, frame from this video. Right: Larger flash - I assume: from firing a rocket, frame from this video.

The left and centre frames above are from different videos both showing the L-39 with what I believe to be muzzle flashes from firing an auto cannon mounted underneath the pilot compartment. The flashes occur during dives which corresponds with the way of using such a constricted cannon. In the frame to the right much larger flashes occur at the side of the plane, and I believe this to be a recording of the L-39 firing some kind of rockets. (video-links in caption).

These two types of armament would be in accordance with the L-39ZA variant of the Albatros which Syria is listed as operating. According to Wikipedia this variant can carry a 23 mm auto cannon, and is able to fire K-13s and R-60s rockets(note 2). The two models of rockets mentioned are not fired from multiple rocket pods (like the S-5) but are mounted directly to the pylons under the wings. This in my view corresponds with the large flashes.

* note (added 07/08/2012): As aviation journalist David Cenciotti points out in this post it can be seen that the L-39 in this video (or see image at top of this post) has two under-wing rocket-pods mounted. This makes me think I went to fare in my almost-excluding rocket pods as being used in the video mentioned above (with the larger flashes).

In this Reuters article published on August 9., two photos by Goran Tomasevic are clearly showing an L-39ZA firing rockets from underwing rocket pods. The image caption says:
"A Syrian Air Force fighter plane fires a rocket during an air strike in the village of Tel Rafat, some 37 km (23 miles) north of Aleppo, August 9, 2012."
Syrian activist @HamaEcho tweeted one of the photos in high resolution, and from studying it, it looks to me like the rockets are S-5s and that the launchers could be UB-16-57UMPs.
The under fuselage auto-cannon is also clearly visible under the pilots compartment. (this Reuters-section was added 09/08/2012).

Video with clear view towards L-39 firing its autocannon. (link replaced 13/01/2015).

Bombs:

Syria is also listed as having the L-39 in the ZO variant. This version is a predecessor to the L-39ZA and is not made to be armed with either auto cannon or rockets. But it should be able to carry bombs. (could be wrong: see note 3):
"…Four pylons stressed for 500 kg (1,100 lb) (inboard) and 250 kg (550 lb) (outboard), with total external load of 1,150 kg (2,500 lb)" (qoute: Wikipedia, but see note 4).
The frames below are from a video, that seems to document a case of an L-39 dropping a bomb at the city of Manbej 80 km East North-East of Aleppo.

Left: object can be seen falling from the plane (marked with circle). Right: the somke/dust rising from the explosion.
Source: video uploaded 02/08/2012 to Msyria89's YouTube Channel.

In full screen and highest resolution it can be seen, that an object is falling from the plane at 0:15 - 0:16 min. It's not easy to spot and in theory it could also be a manipulation, but at about 15 seconds later a large explosion occurs on the ground not fare from the camera. By calculating the distance of a 15 second free fall I get something like 1100 metres, if there is no wind resistance - which there is. And without knowing exactly how much less the distance would be with wind resistance, I think it matches the altitude of the plane quite well.

The frame below to the left is from a video that appears to show the crater of the bomb dropped in the frames above. And as can be seen it's a big crater. But even so; compared to other craters that I believe are from 250 kg OFABs this crater looks considerably smaller.
Now, making such a comparison does not amount to any kind of proof since a number of factors could play a role in this crater being smaller. The reason I mention it anyway is that 100 kg OFABs have started to appear in a number of video reports. The frame below to the right is from one of these reports. It is uploaded to the same channel as that showing the crater, and it shows what must be two unexploded 100 kg OFAB bombs (OFAB 100-120). These are a little less half the size of those reported dropped by Mil Mi 25s. To me the OFAB 100-120s could fit both the size of the crater, and also with being carried by a relatively small jet like the L-39.

Left: A crater. Frame from this video.Right: two OFAB 100-120, frames stitched together from this video.
Both videos uploaded 02/08/2012 to Msyria89's YouTube Channel.
.
In an earlier video also on the same channel a sand-bagged check point can be seen close to where the bomb hit, and I find it likely that either the check point or the building it guarded was the target of the bomb. In that case it missed. Not by more than maybe 50 meter, but enough to leave the target unharmed. Instead - according to reports via New York Times - a woman, on her way to the health clinic, in the building closest to where the bomb hit, was sadly killed.

Another case, of what could look like a similar jet-dropped bomb, has been video-reported from Aleppo. In this video the sound of a passing jet can be heard, and at about 10-12 seconds later a large explosion occurs close by. In this case the model of plane is uncertain, but the timespan, between the sound of the passing jet reaching the microphone, and the explosion, matches a drop like that in the video from Manbej. I have not been able to verify the location of this last video, but judging from the direction and the angle of the sun, the street will be running East-West, and - assuming this is recorded in the evening - the position of the camera is on the North side of the street. The video claims, that the area is purely civilian. I can not determine if that is true, but in this case too it seems, that even though the bomb make a huge blast, the effect - from a military viewpoint - could be quite insignificant.
(* note: this video linked to above has since been taken down, and I have not been able to find a kopi, sorry)

* Please notice: Even if the bombs to the right in the illustration above didn't detonate as intended, they are not safe to handle. Handling and driving around with those bombs represents a great risk, since there is no way of telling what might cause them to detonate. The frame in the left side of the same illustration shows what kind of danger this puts those handling the bombs - as wel as anyone within a quite large radius - in.

Unexploded ordnance (UXO) should not be picked up, and should only be handled by professionals. Anyone else should observe the ARMS guidelines:

- Avoid the area
- Record all relevant information from a safe distance
- Mark the area to warn others
- Seek assistance from the relevant authorities

- link to print-out poster and warning flags in Arabic and English from R.R.M.A. 
(notice updated December 19, 2012)

Update August 9th:


One more video has come out. It is has the title:

"Aleppo - Alsakhur | | for the moment the plane of the rocket launch 07/08/2012"(Google Translate).
I can not say anything about the stated location or the date of the recording, but as can be seen in the images below the L-39 does drop something.

Frames from video uploaded 07/08/2012 to AENNetwork's YouTube channel (via @HamaEcho)
.
What exactly was dropped I can't say either, but it was attached to the outer of the two pylons under the left wing - and it was not a rocket or missile. The way that it travels after being released (losing forward speed relative to the plane and descending) would be consistent with a free fall bomb. This makes me assume it's another OFAB 100-120 bomb. 
A similar looking object can be seen attached to the outer pylon on the right wing.

Video uploaded September 2nd: a 5 minute video with an L-39 circling overhead, and dropping two bombs. According to the title the video is recorded in Al-Bab about 35 km to the North-East of Aleppo. The plane drops its second bomb quite close to the video reporter. It is a scary glimpse of what it must be like to be subjected to such an attack.
.
a frame at 2:51 min. from video uploaded 02/09/2012 to basselstat's YouTube channel.
.
I have tried to use the recording to compare the bomb (the frame above) to online material about the OFAB 100-120, and I find it very likely that the bomb is of that model. However the material doesn't make it possible to be certain, only to say that I found nothing that contradicted a match. (video-section added 03/09/2012).

Online Focus has published a photo that gives a clear view of a Syrian L-39 dropping two bombs. The bombs have been identified by others as OFAB 100-120, and I believe they could be right, but I'm not able to make a definitive matching. They could look a bit too slim. Here is the photo in high resolution. (links added 02/09/2012).

Another high resolution photo of a double bomb drop, published by Sky News, was tweeted by Syrian activist @HamaEcho. I suspect it is of the same drop and by the same photographer as the one linked to from Online Focus. In this photo the bombs are seen as silhouettes, and the they seems to have noses that matches the OFAB 100-120. (link added 02/09/2012).

Video uploaded on August 31st: An L-39 dropping two bombs. According to the title of the video it was recorded North-East of Aleppo in Al-Bab. During the video there is no sound of the bombs detonating. Assuming a maximum of 15 seconds for the bombs to drop to the ground, that would leave about 5 seconds for the sound to reach the microphone. This would mean that if the bombs did detonate the reporter had to be at least 1.5 km away from the impact site. To me it looks unlikely, but I can't rule it out. (link via @Brown_Moses, added 05/09/2012).

Video uploaded August 29th: An L-39 reported over Taftanaz, Idlib.
One more video with same date and location.
* note: the two previous videos linked-to have been taken down, sorry.
And a third that appears to show an L-39 dropping a bomb. These are the only reports I have seen of the L-39 being used in Idlib, and the date and location matches the attack on Afis helicopter base 2.5 km South of the Taftanaz. Two other videos (here and here) uploaded the following days to the same channel (as the third L-39 video), and stating the same location, show unexploded OFAB-100-120s (100 kg unguided free fall bombs). And since - by now - that type of bomb appears to be the typical bomb, for the L-39 to drop, I find that these videos support each other.
More videos uploaded during the last two weeks seems to document the heavy retaliation the town has been hit with. This video shows, what I view as the typical OFAB crater, and the thick metal pieces, that are collected, correspond well with the casing of the OFABs.
(links added 14/09/2012).


Video uploaded September 21th: 'Aleppo - Basha grove | | Albatros military jet bombed 09/20/2012' (Google Translate). An L-39 dropping two bombs at 0:11 and sound of explosion with smoke/dust at 0:27 min. (link added 21/09/2012).
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L-39 hit (update September 29th):
frame from video on ktibetahbaballah's YouTube channel. Uploaded 22/09/2012.

A number of videos, uploaded to ktibetahbaballah's YouTube channel on September 22th, apperas to show an attack by opposition forces on a military base close to Al-Atarib.
During the attack - according to the reports - the opposition fighters were targeted by an L-39, which they managed to hit. The frame above is from one of the videos recorded during the attack on the military base (HQ of the 46th regiment, according to reports).

Left: frame from video on UnionOfAleppo's YouTube channel. Uploaded 22/09/2012. Right: frame from video on شبكة أخبار حلب و إدلب (AENN) YouTube channel. Uploaded 22/09/2012.

Two videos on other channels is said to show the L-39 after it was hit. Location and date is not possible to verify, but one of the videos (frame above to the left) shows a jet leaving a trail of smoke, and the shape of this jet looks a lot like an L-39.
The other video also seems to show a plane on fire (centre of frame above to the right). In this video it is not possible to see what model of plane that is being recorded, but loud cheering at least in part supports the title of the video:
"Aleppo | | Islam Brigades down warplane 22/09/2012."(Google Translate)
I have seen no video-reports or photos of the wreckage or other documentation of the plane actually being downed, but I'm resonably convinced that an L-39 was hit.

Other videos on ktibetahbaballah's YouTube channel show two truck mounted heavy machine guns: a DShK (12.7 mm) and a KPV (14.5 mm). It could be one of these weapons that managed to hit the plane, but the channel show more truck mounted heavy machine guns.

Video showing truck mounted DHsK firing at a Mil Mi 25
Video showing at least four Misrata style black pick-up trucks with heavy machine guns mounted.

Al Jazeera report on the claimed downing and the attack on the military base.

Video overlooking the besieged base (link and location via @Markito0171).
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L-39 shot down (update October 13):
Tail section of downed L-39. Image sources: left, video uploaded to UnionOfAleppo1's YouTube channel. Right: video uploaded to muhamad abdallah's YouTube channel. Both uploaded on 13/10/2012.

Two video-reports of a downed L-39 have come out. According to the titles of the videos the recordings are from Western Aleppo, and according to @Markito0171 it should be in this area. I have seen no claims about what weapon was used to shoot down the plane

The identification of the jet should be certain. My main basis for the ID is the characteristic design of the exhaust opening (frame above to the right).
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More cases of downed L-39s: 
(added Februar 13, 2013)

Since October 13, 2012, there have been more video-reports of L-39 jets being shot down. I have listed three of which at least the two seems to represent solid cases:

October 15, 2012, East North-East Aleppo / Al Bab
November 1, 2012, West of Aleppo / Anjarah* (I have not been able to exclude that this case is the same as the October 13 case).
November 27, 2012, South South-East of Aleppo / Al Muntar (go to 8:40 min) (some uncertainty about the exact date).
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The L-39 base, Ras El Abound, under attack.
(added December 21, 2012) 

By December 21, 2012 at least one of the airports where the L-39s are based was under attack. Some of the material is collected here. (linked to map has been deleted, sorry).
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The L-39 base, Jirah, captured by opposition forces.
(added february 12, 2013)

On February 11, 2013, opposition forces declared the Jirah airbase about 70 km east of Aleppo taken, and video footage shows opposition fighters inside the airbase. Other video-reports claim to show opposition fighters besieging the airbase back on December 27, 2012, but I have no clear information about the exact date of the start of the siege.

Video-reports also show a number of L-39 jets in hardened hangars. The total number and operational status of the captured jets are unknown. One of the jets seems to have the under fuselage autocannon pod of an L-39ZA, but I can't say if this is conclusive.

Video-reports from inside the base. (linked to playlist has been deleted, sorry).

Location in Wikimapia.
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(I have removed some material about video-reports of MiG-21 and MiG-23 from August 13, 2012, from this post, but is the material is stil included in the post Syrian Airforce Unleashed)
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Related material:

The formidable British blogger Brown Moses has compiled many of the video reports with OFABs here, and in this post he was the first, that I saw, to identify the L-39 Albatros as the plane used against Aleppo.
.
New York Times journalist C. J. Chivers gives an insightful run-down and capacity assessment of the use of helicopters by the Syrian Air force as well as the first appearances of fixed wing air-crafts in this article. And The New York Times' Watching Syria's War project has looked at the video with the L-39 dropping a bomb at Manbej here.
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Blogger The Independist (aka @Independist) has spotted around 50 of the L-39s in aerials of two air bases East of Aleppo. the findings are posted here.
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Prague Daily Monitor draws a historic parallel, and asks the relevant question of how it can be that the Syrian fleet of L-39s are still operational. (link added 19/08/2012).
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* note 1: when I write "L-39" this is to be taken as a reference to the visual matching made to this model from the videos. I don't know if this identification is considered absolutely certain, but it is corroborated by knowledge of the Syrian Air Force having these in its fleet (Wikipedia lists Syria a having between 40 or 70 of the L-39 in two variants).
* note 2 (added 05/08/2012): the rockets mentioned are both air-to-air missiles, but I would expect them to be air-to-ground rockets, and by the section with the Reuters photos, the thought of rockets mounted directly to the pylons - in relation to the present use in Syria - seems a lot less likely. (note edited 22/08/2012).
* note 3 (added 08/08/2012): I have since seen photos of what is labelled an L-39ZO with under-wing rocket-pods. I'll leave it open what can be mounted to the under-wing pylons/hard-points of the ZO variant, but I still find that the auto-cannon must require too much modifying to be carried by the L-39ZO.

* general note: please keep in mind that this is not an expert analysis, but a presentation of observations and thoughts. Please apply your own judgment.



Related posts on this blog:
- Hama
- Rastan
- weapons used on Homs
- Syria: Local photo sources.

- any corrections or additions are welcome. Either leave it as a post-comment or @ my twitter acount.