What You Don't Know About Radar By Lary George Have you ever wondered how you appear on the radar screen to other boaters on their radar systems? This has crossed my mind on more than one occasion simply because we were in pea-soup fog – and had to rely on radar and foghorns. Most radar will not lock on to a target unless the target appears in at least half of the sweeps by the radar array. Most boaters think that just because they are operating radar, that they too are generating a radar signature. This may not be true in all cases. Some radar’s will interfere with other radar signals and generate interference. IR (Interference Rejection) filters will remove most of the interference in the radar and that keeps the radar working in heavy traffic. If you are in the vicinity of large ships, which use more than one radar on the same vessel – you should realize that these ships have more stringent requirements for radar detection. IMO (International Maritime Organization) has safety requirements for SOLAS (Safety Of Life At Sea) vessels. IMO requires boats under 150 gross tons to carry a radar reflector that will meet the requirements of RCS (Radar Cross Section). This means that a vessel has to display a 10 square-meter RCS area from certain angles and 2.5 square meters from all other angles. The most recognized radar in use today is X band, which is mandated for all SOLAS vessels; but large ships will also use S band radar for more adverse conditions such as storms and rainy conditions. Many boaters think they have enough hardware above the surface to create a good radar signature, but this can be misleading. One of the things you should do is to get a friend who also has a radar equipped boat to go out in good conditions at the same time, so you can target each other and see exactly how each other’s target RCS looks on a radar screen when underway from different angles. If you are not showing up clearly, you may need adjustments that can be made by a certified radar technician as needed. The alternative is to buy a radar reflector that will improve your reflected image. Knowing and practicing the use of radar in good conditions will give you more confidence before you experience the actual condition of having to navigate via instruments such as radar and other signals. Remember that your equipment will not be as effective in rough seas, rough weather and in other adverse conditions. If you are navigating waters that have SOLAS vessels, busy shipping lanes, or heavily populated areas for boats, it may be a good idea to know what image your boat projects to others. Sometimes it’s better to be seen and not heard. If you feel inadequate in your appearance on radar, you should look into adding a radar reflector to increase the size of your reflection on the radar screen! There are two types of radar reflectors that are currently effective in altering your boats RCS to others. One is passive in design. Fiberglass boats and wooden boats are notorious for having poor reflective radar capability and many have passive reflectors installed. Passive reflectors generally have geometric shapes that have many perpendicular surfaces directed at the horizon. These units do not work very well. The second type of radar reflector would be like the Cyclops 3, which is an "active" (powered) IMO approved radar reflector. Dimensions are 10"H X 17"W X 18"L fiberglass case. The Cyclops receiver listens for incoming radar pulses, amplifies the signal and re-sends the signal back out. The Cyclops is capable of retuning radar pulse by use of "di-electric lense" technology developed by the British during the Falkland War. The technology was good enough to be employed for use in misdirecting radar guided missile fire away from intended targets by creating new larger targets. The Cyclops is manufactured by North Sea Navigator. (http://www.northseanavigator.com) Another manufacturer, the Sea-Me (http://www.sea-me.co.uk), is an active antenna that is an 18" high by 2" diameter reflector antenna and has a control head that lets you know when you are being scanned by radar. The Sea-Me and Cyclops sell for about $300- $600 ea. USD. Sea-Me only works with X band radar that is just fine for almost all purposes. Anxiety levels need not be raised by inexperience, weather, fog, nighttime operation, offshore operations and poor equipment. Get out there and learn to use your radar too its full advantage and know how to create a pumped up image of your boat on radar screens in your operating area. Your confidence will help put safety and pleasure in recreational boating. Lary George, Continental Sales, PO Box 15331, Ft Wayne IN 46885, ljgeorge@juno.com is a Manufacturers Rep in the Great Lakes Region