Hi,

I'm designing a model submarine, and need to know what size electric motor I
will need in it.

It will be 4m long (12 foot) and will hopefully beable to pull me along with
it.

If the weight of the sub and me on land is say, 45st with a bit added to be
on the safe side. The sub has a 7 bladed 0.4m prop and is rougly 4m long,
0.5m wide.

So can anyone provide me with a rough idea as to the size of the motor I
will need to power this beast?

Thanks

Michael