Section F. Visual Alert and Electronic Aids

 
Introduction
 Survival equipment designed to signal rescue vessels and aircraft are divided into two general categories: visual and non-visual.  All search personnel should therefore be familiar with the appearance and characteristics of the various visual and non-visual detection aids (VDAs) carried on boats, lifeboats, rafts, and as personal survival gear.  These may include flags, mirrors, flares, smoke canisters, or something as simple as an orange life raft orange life vest.
Because of the difficulty of sighting a lifeboat or life raft from the air, the first sighting will often be made through the use of a visual aid such as the following:
. Pyrotechnics

. Dye markers

. Signal mirrors

However, typically the SAR platform identifies the general vicinity of the distressed vessel/person by use of electronic means, such as:
. ELT

. EPIRB

. PEPIRB

. Portable two-way radio

There may be times when a close check must be made of a vessel to determine if there is trouble.  A small boat in deep water and showing no wake may be unable to anchor or use power.  A close fly-by may allow observation of more details such as additional signals or sighting data which may indicate distress.
 
F.1.  Raising Antennas
 Survivors may use balloons and box kites for raising antennas of emergency radio sets.  These may indicate the presence of a life raft but can be a hazard to search aircraft.  Be alert for such hazards.
 
F.2.  Signaling Mirrors
 Signaling mirrors are one of the best daylight aids.  When properly operated under ideal conditions, they are visible at distances of 5 nautical miles or more.  In addition, these devices are reusable resources, and may be used indefinitely.
 
F.3.  Canvas Protective Covers
 The canvas protective covers used on life rafts are generally painted red, orange, or yellow and may be used for signaling.  They can also be used for limited messages using the surface-to-air signals or Morse code.
 
F.4.  Pyrotechnic Signals
 Pyrotechnic signals are used as both day and night visual aids along with handheld or floating smoke signals, used in daytime.  These emit a large volume of bright orange smoke that remains visible for several minutes.  Under high wind conditions the smoke will dissipate rapidly making the signal less effective.  Handheld flares, although better at night, may also be used as daytime signals.  Coast Guard or SOLAS-approved marine-type flares are much brighter than the old fuse-type and are therefore much more visible from an aircraft.
 
F.5.  Flare Pistols
 A common pyrotechnic signal-launching device is the flare pistol.  These come in various sizes including the “pen-gun”, which is the size of a fountain pen and fits in the pocket.  The flares are usually red in color.  The meteor signal fireball can reach altitudes of 200 to 1,800 feet depending on the size and type.
　
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