NOAA Fisheries conducts research projects near the mouth of the Columbia, for which they operate a fleet of small research craft based at Hammond, Oregon.   One of the boats, MAGISTER, a 28-foot, stern-drive monohull is used for hauling a net to sample aquatic life.  It was also used to transport a Zodiac inflatable.  Since these operations involved modifications that were not part of the original design, NOAA hired Alan to assess the boat's stability and also towing rig strength.  Based upon the analysis, the hull was lengthened by about three feet, with the addition of a pair of voids at the stern, located abreast the center outdrive unit, as shown in the 3D model below.  The A-frame was permanently removed and a new towing bitt was installed.  The photos below show MAGISTER, before and after the stern extension.


         MAGISTER "before"    

                                                                                                                                MAGISTER "after"  
                                                                                                                                 3-foot stern extension added P/S to MAGISTER

3D rendering of stern extension 

MAGISTER after stern extension added