A one-person, plastic minisub or dinky boat powered by a large replaceable canister of baking powder at the back. The sub or boat must be styled to look as if it came out of a cornflake box.

The baking powder is introduced little by little into a mixing chamber by a gravity fed valve. A nozzle directs the resulting fizz backwards. Optional turbo-boost can be provided by squirting lemon juice or vinegar into the mixing chamber.

Only minimal steering will be necessary as this is only intended for pootling around in shallowish waters. A rudder with foot controls as used on some canoes/kayaks would suffice. Alternatively, the outlet nozzle could be manouverable.

For the sub, diving could be acheived by a simple system of weights which could be jetisoned when you wish to resurface. Another method could be to counteract the weights by flooding the baking powder canister when it is nearly empty to increase fizzing and bob the sub up to the surface. The initial weight of the baking powder will also help you to sink.

An added advantage is that baking powder is slightly on the alkaline side of neutral and experts are worried about the rising acidity of the earth's oceans, caused by the the increasing amounts of carbon dioxide in the atmosphere. So you would be helping, in a small way, to redress the balance.
-- squeak, Oct 28 2003

International Submarine Race http://www.isrsubrace.org/
You might find one here. [phoenix, Oct 05 2004]

Baking powder rocket launcher. http://granadakids....56/show18item2.html
[squeak, Oct 05 2004]

How baking powder works [linty] http://science.hows....com/question57.htm
FFzzzzzzz! [squeak, Oct 05 2004]

I know baking soda and vinegar will give you a good fizz, but I am not so sure about baking powder and water. Isn't baking powder just baking soda (sodium bicarbonate) and corn starch? I don't think there's a gas produced when you add water.
-- lintkeeper2, Oct 28 2003


No baking *Soda* is sodium bicarbonate. Baking soda needs an acid to make it fizz . Baking powder already has the acid added in the form of cream of tartar (as well as the corn starch you mention). All you need to add is moisture and it begins to fizz, giving off CO2 which is what makes your cakes fluffy. If you add an acid liquid such as lemon juice or vinegar instead of water, the reaction speeds up considerably. See link for explosive results.
-- squeak, Oct 29 2003


How much baking powder are we talking?
-- k_sra, Oct 31 2003


A lot.

Bear in mind, these are only meant for toodling around for fun. Not for deep-sea exploration or whaling expeditions.
-- squeak, Nov 04 2003



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