Performance

The following data was obtained on Lake Washington by making two runs in opposite direction at the same RPM and averaging the speed in each direction.  Wind and sea conditions were calm.  The boat was about 3/4's full on fuel and H2O.

The fuel consumption is from the Cummins specifications for the 6BT5.9M 210HP diesel.

RPM	Speed	Gal/Hr	NM/Gal	S/L
1,000	5.5	1.7	3.2	0.93
1,200	6.2	2.1	3.0	1.06
1,400	6.8	2.7	2.5	1.15
1,600	7.3	3.5	2.1	1.24
1,800	8.0	4.6	1.7	1.35
2,000	8.4	5.9	1.4	1.42
2,200	8.7	7.4	1.2	1.48
2,400	9.1	9.4	1.0	1.54

My "real world" data is actually better than the data above suggest.  In our trip to Desolation Sound in May 2006, we put on 66 engine hours, burned 133 gallons of fuel (i.e., ~2 gal/hour) and traveled 396 miles (~3 NM/gal).  The engine hours includes the idling time while docking and anchoring.  The fuel consumption includes operating our 5KW generator and our diesel furnace.