Giant Firefighting Blimp
bgood writes: "MSNBC has an article about a California firm's plans for building a firefighting airship. Wetzone Engineering is working on a prototype and hopes to have a production craft in use within three years." Looks like a great way to water the lawn, too.
Flammability: Modern airships use non-flammable helium (the manufacturers don't appear to state what they plan to use in this case). The Hindenberg only burned strongly because of the flammable metals in her skin; the hydrogen vanished, literally, in a flash. Even then, more than half of the passangers and crew survived:
http://www.dwv-info.de/pm/hindbg/hbe.htm
Speed: Airships can manage up to 80 knots
http://www.airship.demon.co.uk/whatis.html
Weight / lift capability: 'just under' 1 million litres of water weighs 'just under' 1 thousand tonnes. Guess what? The air-buoyancy of a helium airship this size is 'just under' 1 thousand tonnes (I won't bore you all with the math).
The only scary thing about this airship is the fact of 1000 tonnes of *anything* flying around overhead (Although a fully laden Boeing 747 has a max take-off weight up to 400 tonnes:7 ).
http://www.aerospaceweb.org/aircraft/jetliner/b74
If it did crash, however, it'd be the world's biggest water baloon.