Need advice on simulating explosions

[bhays]

We are doing a full tilt WWII era battle scene in out haunt next year (it has to be done April 29th for the Hauntcon tour) and I need some advice on simulating explosions. We are using the propane machine guns, and even pneumatic effects to simulate bullet hits, but I have a couple of spots where I need to simulate an explosion, for example:

A soldier will come running to the group and ask them to follow him to safety, along the way, an infected soldier will come out of a door at them.. the guide will shove him back in the door and toss a grenade in, then I need to simulate the grenade blast behind the door.. what would you recommend to simulate the grenade going off? Obviously, I need a loud explosion sound and a flash of light.. but is there a better way to do it than just a large powered speaker on the controller and a big flood bulb? What about some sort of pneumatic effect to kick up a cloud with the blast?

Has anyone done something like this who might have ideas?

[Jim Warfield]

I have..

Just tied a string to a small stick, pushed the stick into the dirt, covered it with more dirt, covered the string with dirt, then yanked the string simulating an explosion. Of course When I did this I was only 10 years old!
Get a camera close enough it might look good!

[NightmareOnYourStreet]

You could make some sort of chamber hooked up to an air cannon. pump smoke into the chamber then when the explosion goes off a huge puff of smoke goes out when the air shoots out. jsut an idea. not sure how you can make it work but i know it can be done

[Darkangel]

Maybe it's something you can achieve using a DMX controller? I think you'll need a combination of fans for wind, flames and heat, and great audio and lighting... I'm sure to an expert it's pretty easy to do.

DA

[gadget-evilusions]

Fog cannon, Air amplifier cannon for wind blast, another debris cannon, flood light, too bad you can't put a flame cannon in there

[Allen H]

If the wall opposite the doorway was made of scrim and lit from the hallway side, then when the explosion triggered the scrim wall could be lit from the other side showing holes blown into it or other damage.
I have seen this used super effectively at the muppets 3d movie show at Disney and I have been waiting for a chance to use it.