Another variable is how the boat is balanced. One time in my Boston Whaler, the grand kids had fun sitting in the very front of the boat while we under power. All that weight forward meant we were plowing thru the water more than normal. As it turned out we used way more fuel than normal and barely made it back. Lesson learned.
Sounds like you have a bunch of grandkids to fish with. The trip was worth every ounce of fuel burned. I do understand the almost ran out of gas part, it's scary trying to make it back to the dock on prayers & fumes. I just had 3 weeks fishing with my grandson & it was the best 3 weeks I've had this year. He's an army brat & I don't get to see him often but at 14 he loves to fish.
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