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Outstanding, I think this is the first underwater model rocketry project we’ve featured here, finally!

Joe Peck has extended the pursuit of realism in model rocketry to the launch environment. Think Poseidon here — this rocket launches from underwater. Initially, it’s sealed watertight from nose to nozzle. Ignition is triggered by bringing a magnet close to a sensor contained in the upper section. The motor ignites, blowing off the bottom end cap and we have liftoff! If you’re into model rocketry, here’s your next challenge.

Case #97: Project Dragon Fish: Joe Takes Rocket Science to New Depths – 2/5/2007 – Design News – Link.