multi-motor?

[koenejet]

First let me apologize in advance if this is a common question, but I can't seem to find an answer, so hear it is:

I saw a pic somewhere online (can't remember exactly), but it was of two brushless motors connected together to a common gearbox. This got me to wondering a few things:

First, does this in effect double the horsepower? So, for example (using easy numbers) if one needed 2hp to power his heli, could you use two 746watt motors (1hp each)?

Also, I'm assuming you would use two separate ESCs with the signal wires 'Y'ed together.

What is the real reason for doing something like this?

Thanks for any input.