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7110.65R
AIM
AIM      CHG 2                                                                                             3/15/07
                                                                                                           5/26/16
                                                                                                          12/10/15


                                                    FIG 7-1-11
                                     Microburst Encounter During Takeoff




 A microburst encounter during takeoff. The airplane first encounters a headwind and experiences increasing
 performance (1), this is followed in short succession by a decreasing headwind component (2), a downdraft
 (3), and finally a strong tailwind (4), where 2 through 5 all result in decreasing performance of the airplane.
 Position (5) represents an extreme situation just prior to impact. Figure courtesy of Walter Frost, FWG
 Associates, Inc., Tullahoma, Tennessee.




  e. Microburst wind shear may create a severe              experience of penetrating one is characterized in
hazard for aircraft within 1,000 feet of the ground,        FIG 7-1-11. The aircraft may encounter a headwind
particularly during the approach to landing and             (performance increasing) followed by a downdraft
landing and take-off phases. The impact of a                and tailwind (both performance decreasing), possibly
microburst on aircraft which have the unfortunate           resulting in terrain impact.




7-1-46                                                                                                Meteorology