Fuel Air - adding fragments and as a source of propulsion

Discussion in 'Weapons, Equipment & Rations' started by gobbyidiot, Aug 1, 2008.

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  1. What I was wondering about last night -

    a) fuel air pretty much relies on overpressure, throwing the casualty into objects, or (less so) firing objects at the casualty. In bare-arse terrain you would think that fuel/air would work less well. Suppose the packet was surrounded by shot/foil blades/something similar. The packet pops and sprays the fuel and foil and then the spark initiates the bang. Would some of the foil blade (I'm thinking something the dimensions of razor wire) hang in the air long enough to be driven by the blast? Things fall 10m per sec ignoring air resistance, but air resistance can be significant with some things. Would falling through a cloud of fuel slow it down further? If it fell to the ground might it get usefully driven by the blast anyway? If it was light enough to work would it be too light to retain velocity?

    It just seems to me that a fuel/air bang in open country looks impressive, but in the absence of fragments might not achive much.

    b) How fast does the cylinder of a car engine move? Could you fire a mortar round with a tube and a bomb with a base plate acting as the "piston" in the cylinder, and a combustion chamber at the bottom, fuelled by a little bottle of petrol? I'm guessing that you wouldn't get enough velocity, and the weight of propellent saved would be low.
  2. Try Horlicks in case it happens again. ;)
  3. Biped

    Biped LE Book Reviewer

    Part of the problem is the speed at which you can disperse the fuel, against the speed at which you can disperse the 'splinters' - the fuel-air dispersal is pretty much immediate, whereas the fragments have greater mass and would need to be outside the fuel radius to get the full acceleration. Anything within the pressure or heat wave area will be bowlarked anyway, so the frag will just be OTT.

    Also, fuel-air is more effective than anything else when getting around objects or through confined areas, such as tunnels, buildings etc. It's primary effect is a pressure wave, secondary being a heat wave - both of which can go around corners, whereas fragments can only richochet.

    It's sort of gilding the lilly TBH, and probably more effort than it's worth.

    Having said that - WTF is wrong with fuel-air anyway - pretty damned effective if you ask me.

    As for point 'b' - stay off the drugs - mortars work just fine too.

    Now, fuel-air mortars - NOW you're talking! :twisted:
  4. Good Nytol!
  5. Which you can get delivered by the cheapo line of sight weapon delivery system you were thinking about on a different thread? Seems to me you are spending slightly too much time on the sofa wan*ing off to great big death dealing ideas, or you should maybe just get out more?

    Interesting thought though, but beware what you wish for, when the 'enemy' build one and lob it in this direction...
  6. Biped

    Biped LE Book Reviewer


    The thermobaric explosive warhead is aimed at creating an incredibly abrupt overpressure and heat in an enclosed space, followed by a deep vacuum. The overpressure can reach a value of between 2.5 and 3 Mpa while the temperature will soar to a mighty 3000 centigrade and create a blast wave that travels at a speed of 3000 metres per second, burning all available oxygen in the process. This explains the more than suitable choice of the word thermobaric to qualify this type of weapon, as it combines the Greek words of “thermo” (heat) and “baros” (literally weight, therefore pressure). Interestingly, the Russian also describe thermobarics as volumetric explosives, quite rightly one has to admit. A very common error made by the non-specialised press is to describe the performance of thermobaric warheads as a weapon that causes a huge vacuum; the vacuum, of course, comes after the huge overpressure wave and results from the combustion of all the oxygen in the vicinity.

    That doesn't leave much work for fragments to do, unless of course you consider the number of high velocity projectiles made from objects in the area of the over-pressure wave - stones, walls, body-parts, personal weapons etc.

    Edited to add:

    The Bulgarian VDMM 81mm Thermobaric is one such example.
  7. Interesting. There's nowt new, lad...., said Uncle Mort.
  8. Biped

    Biped LE Book Reviewer

    Such a weapon in British hands would certainly mark the end of mortar round shortages. Just one might be sufficient to 'saturate' the enemy, or at least, saturate the surrounding ditches with taliban intestines.
  9. Send an e-mail to Mythbusters perhaps they'll try to construct a four cylinder mortar for you.
  10. Biped

    Biped LE Book Reviewer

    Nice idea, but 6 cylinders gives a far smoother and efficient area saturation.
  11. What about a V-8? Hit two targets simultaneously!
  12. Trans-sane

    Trans-sane LE Book Reviewer

    Did the man-packed LAW type thermobarric weapon being talked about at the start of Telic ever get developed/deployed at all?

    As for adding shrapnel of some kind, it wouldn't work. The reasons mentioned above are all good reasons. Another is tiny bits of metal + lots of oxygen + sh1t loads of heat = meatal oxide. Your shrapnel would burn up before it got too your target...
  13. Biped

    Biped LE Book Reviewer

    Well, you could go down the route of the rotary engine - I think it's called a 'dillon', but of course, you'd have to get the 'fuel' in REAL quick.
  14. Biped

    Biped LE Book Reviewer

    The daisy cutter uses aluminium dust of course.