The units have been mounted beside the lw hull and ww hull to maximise turning moment.  They swing up and out of the water laterally for sailing.  The lifting ropes need permanent attachment points and will be thinner high modulus rope.

Since the initial trials with the single Mars 3001 motor we decided on much more powerful Mars 1003 motors for the permanent installation.  These have the simplicity of being brushed DC so could be run without controllers in an emergency by direct connection to batteries.  

The lw unit is not constrained by battery current so it can produce 9kW continuously on the 50V battery.  The smaller battery on the ww side limits power to 6.7kW.  We have not measured bollard pull but it will be in the region of 6000N with both motors on their current limit.

The testing today was for maneuverability rather than speed test and the video shows how the 18m boat can be turned on the spot.

Next step will be to get the hulls clean (again) and do some speed trials.  The range should be around 9nm at 5kts solely from batteries without any extra charging.  Decisions are still to be made on means of charging but plans are to at least set up some solar panels so the batteries can be charged between outings.

Expenditure on the units now totals AUD8,000 in round numbers.  This is for motors, gearboxes, props, controllers, batteries and aluminium housings plus fixings.  This is less than the original 60HP high thrust outboard installation.  Which is now for sale.

The ww unit has ended up mounted lower than planned during design stage so it will be modified to get the motor housing out of the water to prevent the ploughing evident in the video.  The lw unit is set at the correct height and wash is much cleaner.

Props are 540mm diameter and prop shaft is 600mm below the surface on the lw side.  Each drive unit weighs about 35kg.  The lw batteries weigh 60kg and the ww batteries 40kg. Overall weight similar to outboard counting the mounting, starting battery and controls.  The motor housings have been pressure tested for leaks as they are intended to take full immersion.  

Time will tell regarding durability.