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Valley In Flight Training Quarter Page4/C Adthink hail in that echo. Many radars display magenta to indicate storm intensity; magenta signifies hail, little question. (Once more, several years ago the know-nothing bureaucrats decreed that magenta may no longer be used on airborne radars to signify a hail-containing echo; however it can on NEXRAD. Go figure. Today, only turbulence is indicated with magenta, on radars that have the TURB function.)Next, shapes. Begin with round symmetrical echoes. They are most likely just showers or baby thunderstorms. Hail not likely. The more the shape varies from simple round, the greater the possibility of hail. Shapes are only grossly discernable on NEXRAD. The standouts are “pendant” shaped ones and “fingers” of echo. “Pendant Shaped” meaning it looks sort of like a lady’s pendant with a notch in the large end. Sometimes they look like a snake with its mouth wide open. The mouth will be on the downwind end of the formation. (Yes, even for flights that never get above 12,000 or so, it’s critical that pilots know both direction and velocity of winds in the flight levels.) With airborne radar, hail-indicating shapes can be seen clearly, even down inside the red part of the echo, by careful twiddling of that “CAL” control.So, you suspect hail. How far away should you fly to avoid it? The usual advice is 20 nm. But that’s just a partial answer. It’ll help in making the avoidance decision to know that hail strikes rarely occurs in flight above 30,000 feet. Few occur during departures. Most are during arrivals. Reasons are obvious; on departures, it’s usually possible to make wide deviations. Not so on arrivals. In making an avoidance decision, you must also consider turbulence potential.If the storm is wicked enough to be generating hail it’s also generating heavy to extreme turbulence far out from the echo on the downwind side. That’s in reference to winds above 24,000, not low-level ones. To avoid all possible downwind turbulence from a potential hail producer, circumnavigate to•a distance equal to the winds at 24,000 feet and above. That’s even if you’re at only 8,000 feet or thereabouts.So, Hail? No! You just have to know the signs and be observant. Cunning also helps. T&T-Air Capitol Dial Quarter Page 4/C AdArchie Trammell’s credentials are 34 years as an instructor and lecturer on airborne weather radar and convective storms avoidance. His clients have included most major airlines, all five military ser- vices and numerous government agencies, includ- ing the FAA, NASA and NTSB.His research has been exhaustive and has includ- ed more than 4,000 hours of inflight thunderstorm research, both in his own aircraft and from the jump seat for airline clients. He’s a pilot and CFII, with much twin and turbine experience. His monthly web site, www.radar4 pilots.com, has been up monthly since May 2005.14 • TWIN & TURBINEAPRIL 2016