Graupner Shark

The shark is a small submarine kit that Graupner produced.  It's currently out of production which is a shame since this is a nice little boat.  It's a real rocket under water and has the ability to completely jump out of the water when surfacing rapidly.  I was surprised by it's speed since the motor is just a speed 500.  The whole drive system including gear box and counter rotating shafts is super efficient offering very good run times on a single charge, especially if you swap the normal NiCd battery for a LiPo pack.

The size and weight of this boat makes it easy to transport.   The hatch design is pretty good in that it doesn't leak once fasten securely but it's a little time consuming to take on and off since you have to remove two access screws, then use an allen wench to get to the bolts that actually hold the hatch on.