1. Navigational Ranges Definition
“Two or more objects in line” are said to be “in range.”
An observer having them in range is said to be “on range.”
Two beacons are frequently located for the specific purpose of forming a range to indicate a safe route or the centerline of a channel…”

2. Navigational Ranges The Problem
Differences are noted of the location of a boat when “on range” but not in the center of the channel.

3. Navigational Ranges Data Gathering
Record the position data as your boat tracks “on range” down the channel.

4. Navigational Ranges Positioning Data criteria
Record positions only when precisely “on range.”
Record positions at the beginning and the end of the range inside the channel
Take a minimum of 4 positions while “on range.”

5. Navigation Ranges Record Positions
This is the latest Co-operative charting mission that NOAA would like the Power Squadron to participate in. With the advent of navigating on electronic charts, mariners are reporting that when on range using the navaids, they are not in the center of the channel on the chart. We need positions located approximately every one inch at the scale of the chart while sitting precisely on range. The quality of these positions is stressed over the quantity. Around ten readings averaged for each position should be sufficient.
Record
Positions
2003 Aids to Navigation Workshop