10w going a small distance, sure. This page doesn't say how much light was lost over the 5 miles. So I'll put it this way: If you lose just 1% every 5 miles,

10w going a small distance, sure. This page doesn't say how much light was lost over the 5 miles. So I'll put it this way: If you lose just 1% every 5 miles, then by the time you go 2000 miles across an ocean you've lost 98% of your power.