I would say the purpose of such weapons in the Middle East are largely for the fear factor. With the exception of an undeclared stock of nukes in Israel, the Middle Eastern countries raced to thermobaric munitions as the next best thing for making mushroom clouds. They are not really that practical if an enemy has effective air defense, but as Nico pointed out, you can clear mine fields, trench lines, caves, and several city blocks with one of these.
Since it does appear to be an older model I looked into the prototype, which was derived from the FLAGON (Su-15), but this aircraft does not have the appropriate horizontal stabilizers to be the Sukhoi T6-1...it has to be a junked early model FENCER.
Your measurements are good, but I think you are forgetting that the FENCER-A had a shorter nose than subsequent variants. When compared to the other aircraft in the picture, such as the FOXHOUND and FLANKERS and FROGFOOT, you will see it matches up to the appropriate size (assuming the older variant). I can tell you it is not a model D or newer because of the lack of stall fences on the VGW housing. The span will not fit because most of the wings are missing except for smaller pieces fitted...
I have to agree with Kjfitz. You can, using proper technique, clearly figure out what is shown in the image. Of course there are some things which resolution and scale make it impossible to determine.
In this museum, not having been there myself, and just looking at what imagery is available, can see:
A Hind, Hip, MIM-23 Hawk, SA-5, SA-2, SA-3, SA-6, SA-11, SS-21 Scarab, T-80, BTR-60PB, BMP-1, BRDM-2 ATGM, MTLB, THIN SKIN B radar, FLAT FACE radar, LOW BLOW radar...
This motorpool contains SA-6 SAMs, PAT HAND radar, SA-9 TELs, SA-8 TELARs, SA-8 Transloaders, SA-13 TELARs, ZSU-23-4, 2S6M TELAR, SS-21 Scarab, BTR-60PB, Strykers, HMMWVs, SA-11 TELAR...and other additional equipment. I'm tired of typing, but I hope this gives you a bit of an overview.
Alkavian: Comments
Here is an image to help with my explanation.
http://img23.imageshack.us/img23/3002/0szf.jpg
http://en.wikipedia.org/wiki/SA-5_Gammon
Looks to be an M-46 field gun. Nice find.
http://en.wikipedia.org/wiki/Joint_Analysis_Center
In this museum, not having been there myself, and just looking at what imagery is available, can see:
A Hind, Hip, MIM-23 Hawk, SA-5, SA-2, SA-3, SA-6, SA-11, SS-21 Scarab, T-80, BTR-60PB, BMP-1, BRDM-2 ATGM, MTLB, THIN SKIN B radar, FLAT FACE radar, LOW BLOW radar...
They could be awaiting rail or sea transport for deployment. They are old model M109's so my guess is that they are a National Guard or Reserve Unit.
This is the British FV4004 "Centurion". Nice side profile shot and an excellent shot of the split tool boxes (attached to the turret). Very cool.
http://en.wikipedia.org/wiki/57_mm_AZP_S-60
http://www.globalsecurity.org/military/systems/ground/aav7a1-ram.htm