TRAVIS COUNTY DIVE TEAM
SPIRAL SEARCH

Description

The Spiral pattern uses one buoy and three divers. One diver, the Anchor, sits on the anchor and holds the end of the search line. Another diver, the Point or Tether, holds the search line reel and swims a circle around the anchor. The Anchor diver signals to the Point diver when he or she finishes the circle. The Point diver lets out enough search line to cover the visibility range and continues swimming, now covering a wider circle. The third diver, the Safety, stays at the surface. The safety diver keeps one hand on the anchor line for passing signals.

Rope Pull Signals

• ONE pull: OK. Always acknowledged with same signal.

• TWO pulls: START or MOVE.
  • The Anchor signals TWO PULLS to the Point diver when one circle has been completed and it is time to let out more search line.

• THREE pulls: STOP - Pull in search line.
  • The Anchor signals THREE PULLS to the Point to pull in the search line and return to the anchor.

• FOUR OR MORE pulls: FOUND or HELP - Come here.
  • The Point signals FOUR PULLS to the Anchor when he or she finds the search target.
  • The Anchor signals FOUR PULLS to the Safety to come down and assist when needed.
  • The Safety signals FOUR PULLS to the Anchor to stop the search.
  • A diver who needs help signals FOUR PULLS to the others to come and help.

JOB DESCRIPTIONS

ANCHOR - JOB DESCRIPTION:

1. Hold the search line taut and up off the bottom.
2. Signals to the POINT diver when the Point finishes one circle.

POINT (or Tether) - JOB DESCRIPTION:

1. Hold the search line taut and keep swimming.
2. When the Anchor signals "SLACK": let out enough line to cover the visibility range, then continue searching.
3. When you find the search target: signal "FOUND" to the Anchor.

SAFETY - JOB DESCRIPTION:

1. If Anchor requests help (with FOUR pulls on the anchor line): go down and assist.
2. If the search commander wants the pattern stopped, signal FOUR pulls to the Anchor.

Spiral Pattern Operation

Advantages:

The Spiral pattern is good for rescue situations where you have a good starting location. It searches the area close to the anchor first, and it does not require any deployment time after the divers reach the bottom.

Disadvantages:

The Spiral pattern is limited to about 30 feet of search line. With more search line out, the line drags on the bottom. The spiral pattern will not work well if there are obstructions on the bottom than can snag the search line.

Rope-Pull Signals

1 is "OK": always reply with the same signal.
2 is "START or MOVE": start the pattern.
3 is "STOP": stop the pattern; investigate why.
4 is "TARGET FOUND" or "HELP"

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