Mississippi River Skiff under power

The beautiful September weather got us motivated to try out a new spot.  We drove over to Horse Shoe Lake State Park near Collinsville ILL.  With Sunday traffic it only took 30 minutes.  It is exactly 26 miles from our front door.  It is a pretty lake with lots of access.  There is a 50 hp limit and it is mainly used by folks fishing.
We got the skiff in and finally got some video of it under power.
Here it is...

USCG certified capacities for the MRS

After a few back and forth e emails with the Coast Guard clarifying the formulas, we have the certified Maximum Capacity numbers for the Mississippi River Skiff.
They are as follows:

MWC  717 pounds
MPC    497 pounds (calculated with a 20 HP motor)  This is Person Capacity
 Number of Persons  4
 Maximum Horse Power  20

As we ran through the numbers we found the size and width of the skiff could handle up to a 35 hp motor.  But through our testing we felt it should be limited to a 20hp to keep the stern from squatting too much.
So if we limited the HP to 20 the formula allows for more person capacity.  This brought us up to 3.75 persons.  With the addition of 3.15 cubic feet of flotation, the skiff is certified for these numbers.  We will be adding floatation this week.
The USCG has tables for calculating engine. battery and fuel tank weights.  To see them, follow this link:
uscgboating.org/regulations
Or This one:
Gov Printing Office How you arrive at these figure is as follows:

Sinking!

We received our Manufacturers ID from the Coast Guard awhile back.
Our ID is "SEA", awesome.
Any builder of boats has to register with the Coast Guard and meet regulations for safety.
On our application we listed the Mississippi River Skiff as one of our models.  We have since decided to move on to the next design and not produce additional hulls of the MRS.

The de-watering with a submersible sump

Filler up!

But the Coast Guard, now under the auspices of Homeland Security called and wanted us to certify that the MRS meets regulations.
To do this there are calculations that need to be done.  They all start with the maximum capacity of the craft.  This is the weight that sinks the boat to the shear line.

  

To do this we hauled the skiff over to the pool at the house of our friends the Walters.  We shot a video of the whole sinking that we were going to compress into a high-speed clip. Unfortunatly the battery died and corrupted the file.
We did have a successful sinking.  The skiff stayed in trim and evenly sank to its shear line until water spilled in and out but would sink no further.
There are no floatation compartments.  It is simply built of wood encapsulated in a glass/epoxy skin.
It took 72 minutes at a flow rate of 6.451 gpm.
This equals 464.472 gallons.
At 8.33 pounds per gallon, the maximum capacity is 3,869.052 pounds!
We will tackle the rest of the Coast Guard calculations tonight.