Metro-01
Review of Basic Meteorological Principles
c.
Microburst core (predominantly downdraft)
(1) Conditions
(a) Airspeed continues to drop and AOA continues to
decrease due to continuing shift in airmass movement
(b) Descent rate continues to accelerate
(2) Indications
(a) High on glideslope and correcting
(b) “Fast” despite continued back stick
(3) Pilot response: continues to raise nose to arrest descent
rate and to achieve on-glideslope and on-speed with
minimum use of power
(4) Effects: continues unarrested descent in “fast” condition
despite high nose attitude—pilot response is insufficient
to keep up with shift of wind direction
d. Outflow area beyond to microburst core (predominantly tail
wind)
(1) Conditions
(a) Rapid wind shift from downdraft to tail wind causes
sudden decrease in airspeed
(b) Aircraft “blows through” glideslope in a nose-high
attitude
(2) Indications
(a) AOA rapidly changes from “fast” to “slow” due to
excessively high nose attitude and loss of vertical
component of wind—pilot “feels the bottom drop out”
(b) Airspeed continues to decrease
(c) Excessive descent rate
(3) Pilot response: pilot gauges altitude loss and realizes
danger of situation—abandons approach, applies full
power, and holds AOA above normal in effort to arrest
descent
Fig 7: Microburst
(4) Effects: airspeed and descent rate may stabilize;
Windshear Probability
however, altitude loss will continue until aircraft
Guidelines
accelerates to an airspeed that will yield a positive rate of
climb (if possible)
(7-97) Original
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