How to Estimate the Range and Bearing to a Flare

Knowing how to spot the location of a flare can make the difference in locating a stranded boat.

boat flare chart

On the night of April 16, 2004 patrons at a waterfront restaurant on Cedar Key, Florida, sighted a flare out over the water. They told the waitress, who called the Coast Guard. Inside an hour, a family of four, including two little kids, showed up at the dock clinging to their rescuers. They were cold and shaky, but safe.

The skipper had run aground and stranded his family in a remote area. Fortunately, one of the bistro patrons was a U.S. Coast Guard Auxiliarist and knew how to pinpoint the position from which the flare was fired. The techniques for accurately estimating the range and bearing to a flare are simple and should be part of every boater’s bag of tricks. Learn them, and you may one day help save a life.

The Fist Method

Knowing the angle from your position to the flare’s height of trajectory allows the Coasties to triangulate the estimated distance to the boat in distress. Your fist can be used as a poor man’s sextant. Here’s how:

Make a fist and extend your arm. Place your pinky on the horizon and note how many fingers above the horizon the flare is at the height of its trajectory. Each finger represents approximately 2 degrees of arc. For you math nuts, range = 1.856 x elevation/angle. But all most of us need to do is to tell the authorities the finger count, or “percentage of fist,” as it’s known.

Oftentimes, such as with hand-held flares, the signal will appear below the horizon. In that case, align your index finger with the horizon and provide the percentage of fist below the line.

The Clock Method

Note your current heading and position and, using the bow of your boat as 12:00, report the direction in which you sighted the flare as a time of day. Of course, if you can take actual bearing over your compass card, or with a hand-held compass, so much the better.

Flare Color

Red or orange flares are distress signals. White flares are “practice” flares, intended for testing flare guns. Green flares are often dropped from search and rescue (SAR) aircraft while looking for victims.

Your Next Move

When you sight a flare, help rescuers narrow down the search area by noting the following:

  • Your heading and position
  • The time
  • Flare color
  • The interval between flares
  • The duration of burn
  • Flare trajectory (rising, falling, steady)

Call It In

If you sight a flare, get on the VHF and hail the Coast Guard. Would you want your flare ignored? Stay safe.

The U.S. Coast Guard is asking all boat owners and operators to help reduce fatalities, injuries, property damage, and associated healthcare costs related to recreational boating accidents by taking personal responsibility for their own safety and the safety of their passengers. Essential steps include: wearing a life jacket at all times and requiring passengers to do the same; never boating under the influence (BUI); successfully completing a boating safety course; and getting a Vessel Safety Check (VSC) annually from local U.S. Coast Guard Auxiliary, United States Power Squadrons(r), or your state boating agency’s Vessel Examiners. The U.S. Coast Guard reminds all boaters to “Boat Responsibly!” For more tips on boating safety, visit