Professional Pilot, May 2017
RADAR SCHOOL Beware Mae West shaped echoes By whatever name when a little echo is near a big one think danger This classic Mae West echo was affecting Torontos airport as an Airbus A330 approached Note its in a line of echoes which indicates lots of moisture and lift O n August 2 2005 there was rain in the area as an Airbus A330 approached Toronto Their radar showed a weird strong echo suggesting that there were 2 78 PROFESSIONAL PILOT May 2017 cells linked together Some call such a formation the hour glass shape but many refer to it as the Mae West shape because of its resemblance to the flotation vests worn by Naval Aviators during WWII These were named after the famous movie queen of the late 1930s The A330 captain considered diverting to either Syracuse NY or Montreal However other aircraft were continuing to land through the rain at Toronto A diversion would have imposed both a great expense to his airline and significant inconvenience for his passengers since it was a long bus trip back to Toronto So he elected to land at his intend By Archie Trammell President Radar Training Systems Comm Multi Inst CFII A P This visual is reproduced from the NTSB report from an accident at DFW Dallas Ft Worth TX Over the next 5 minutes the very weak cell circled sucked in the large one and exploded Very dangerous is the pendant shaped echo named after a ladys jewelry item If its small end is oriented into the winds aloft and its fatter end is down wind that tells you the storm is so intense it splits those howling upper air winds They flow around it like the eddies in a river around a boulder then they whip back and dig out a dip in the big end In this photo you can actually see the whipping curl upper left After that whipping back what do you suppose the turbulence will be like downwind Fierce And how far About a distance equal to upper air wind velocities is the best estimate Note the scalloped edges on the far side of the red That suggests hail shafts within the red If you reduce the CAL GAIN control settings youll probably be able to pick them out
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