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weather in other nations. Or the world GOES images will give you an indication of how high storms may exist. If you don’t know how to read temperatures in a GOES image, the formulars are listed below it.For height information on your airborne radar, simply select +10o on tilt and apply the rule of 60 – at 1 nautical mile a degree is 100 feet in linear measure. Therefore, at 10 miles each degree is 1,000 feet. With +10o on tilt, an echo at 10 miles reaches to at least 10,000 feet above your current altitude; at 20 miles, 20,000 feet; at 30 miles 30,000 feet. Again, note, that’s above your current altitude.Obviously, if the storm’s max height is below the freezing level, no hail will form. How much above the freezing level must one grow before it likely will? Many years ago thunderstorm research pilot, James M. Cook, the original “Project Rough Rider” pilot, after penetrating hundreds of them, found that almostevery one with a height exceeding the freezing level by 10,000 feet or more had hail of some size in it. Hail damage on his aircraft made the point. Over the USA that means any storm reaching to or above about 30,000 feet may be spitting hail. In areas towards the Poles, the freezing levels tend to be much lower. In equatorial regions, much higher.One must always consider the geographic area.Once upon a time, radar intensity was available from any Controller or Flight Watch Briefer (the latter are no longer available). It was given to us as a VIP number. VIP 5 signified hail possible; VIP 6 hail certain. But several years ago NWS and FAA bureaucrats, in their anti-litigious minds evidently, decided pilots don’t need that much detail. They dropped those precise VIP numbers and switched to meaningless abstractions. Now they tell us only that a weather echo is “Light, Moderate, Heavy or extreme”, all ofno help to a pilot wanting to avoid hail. For example, “Heavy” could mean a simple heavy rain shower or could mean a true thunderstorm with hail. “Extreme” can mean it may contain hail or it definitely does contain hail. Depends on whether it’s low “Extreme” or high “Extreme”. So for most pilots, NEXRAD – as gross as it is – has to do.But, you must also consider that NEXRAD only tells you where it was hailing 5 or 10 minutes ago, not where it is hailing at this instant, or where it will be hailing 10 minutes from now when you get there. On NEXRAD, deepest red, magenta or deep blue at the top of the color scale all indicate hail or possible hail.For radar-equipped pilots, on most airborne radars there’s a method for sorting it out. When red weather is displayed, turn the CAL control down (misnamed “GAIN” on most systems) to the approximate mid position. If red is still displayed,Covington Aircraft Engines Half Page4/C AdAPRIL 2016TWIN & TURBINE • 13