This same munition had appeared in a previous video, posted the day before the UN Inspectors arrival
The first thing that stands out are the nozzles, which indicates this is a type of artillery rocket. Artillery rockets are used widely in the conflict, but what makes this stand out is the number of nozzles. The 107mm rockets used widely in the conflict, launched from Type-63 multiple rocket launches by both sides in the conflict, have less holes than the ten we are seeing here.
There wasn't really much to go on until the team at Allen Vanguard (Twitter) suggested I take a look at the Soviet 140mm M14 Artillery Rocket, fired by BM-14,16, and 17 multiple rocket launcher.
Mark Hiznay of Human Rights Watch provided me with a diagram of the M14, shown below
Two things really stood out, first of all the base of the munition
The same marking, even the same number, is on the diagram of the rocket
Of course, the one way to be sure is to have the exact measurements of the rocket in the video. We can see from the diagram the section in the video should be 140mm wide, and around 630mm long, but how can we possibly find that out? Fortunately, one of the UN inspectors had the same idea, and was filmed measuring it.
Below I've taken a screenshot, copied the measuring tape used by the inspector, and rotated slightly to measure the width of the munition. The tape is resting on top of the munition, but as the camera angle is slightly tilted I've kept the tape near the original position
|Click for big|
|Click for big|
All of this would make this a very strong contender for it being the 140mm M14 Artillery Rocket, and what's very interesting about that is one of it's possible warheads is a chemical warhead loaded with 2.2kg of sarin. This is dispersed on impact, with a burster charge detonating to disperse the agent, which would leave the rest of the rocket intact, unlike a high explosive warhead that would serious damage the rocket on impact. Of course, without testing on the ground it's impossible to be sure this is the type that carries a chemical warhead, but fortunately, that's what the UN are there for.
Update September 9th The RUSI has put out this video with a lot more information on the munition
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