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|
Attributes | |
ACN | 785651 |
Time | |
Date | 200805 |
Local Time Of Day | 0001 To 0600 |
Place | |
Locale Reference | airport : zzz.airport |
State Reference | US |
Altitude | agl single value : 1000 |
Environment | |
Weather Elements | Windshear Thunderstorm |
Light | Night |
Aircraft 1 | |
Controlling Facilities | tracon : zzz.tracon tower : zzz.tower |
Operator | common carrier : air carrier |
Make Model Name | B717 (Formerly MD-95) |
Operating Under FAR Part | Part 121 |
Flight Phase | descent : approach |
Route In Use | approach : visual |
Flight Plan | IFR |
Person 1 | |
Affiliation | company : air carrier |
Function | flight crew : captain oversight : pic |
Qualification | pilot : atp |
ASRS Report | 785651 |
Events | |
Anomaly | inflight encounter : weather other anomaly other anomaly |
Independent Detector | aircraft equipment other aircraft equipment : caws other flight crewa |
Resolutory Action | flight crew : diverted to alternate flight crew : executed go around |
Supplementary | |
Problem Areas | Weather |
Primary Problem | Weather |
Narrative:
Arriving at ZZZ; the field was reporting VFR with strong thunderstorms reported and noted by flight crew 7 mi north of field moving slowly sse. An initial southerly runway assignment was given and as the aircraft approached the field; the crew request a northerly runway because they considered the thunderstorm too close to the airport for a safe base to final turn. The aircraft was given a heading for a visual approach to runway xxl and eventually cleared for the visual approach. The aircraft was configured for landing using flaps 40 degrees; inside the FAF when the captain noted verbally an increase in airspeed; a decrease in power (autothrottles on); and the aircraft pitching up and gaining altitude. The captain decided to execute a go around and turn right to a heading of 090 degrees (as briefed before the approach) to avoid the WX at their 12 O'clock position. As the plane was starting the turn; the 'headwind shear' alert was announced over the CAWS system. A few seconds later; as airspeed bled off quickly; the system called out 'tailwind shear.' with the aircraft below 1000 ft AGL; emergency power was selected and a standard windshear recovery was performed maintaining altitude with airspeed hovering around the 140-145 KT range. Emergency power was used for a period of 5-15 seconds until it was determined that the aircraft was clear of the event and normal climb power was restored. The fadec switches were reset to allow for use of the autothrottles and the aircraft proceeded to ZZZ1 for a landing. The event was caused by the convective thunderstorm located north of the airport. The aircraft was VMC; and the tower reported steady state winds until just before the incident occurred.
Original NASA ASRS Text
Title: B717 FLT CREW EXPERIENCES WINDSHEAR ON VISUAL APPROACH AND USES EMERGENCY POWER TO ESCAPE; WITH DIVERSION TO ALTERNATE.
Narrative: ARRIVING AT ZZZ; THE FIELD WAS RPTING VFR WITH STRONG TSTMS RPTED AND NOTED BY FLT CREW 7 MI N OF FIELD MOVING SLOWLY SSE. AN INITIAL SOUTHERLY RWY ASSIGNMENT WAS GIVEN AND AS THE ACFT APCHED THE FIELD; THE CREW REQUEST A NORTHERLY RWY BECAUSE THEY CONSIDERED THE TSTM TOO CLOSE TO THE ARPT FOR A SAFE BASE TO FINAL TURN. THE ACFT WAS GIVEN A HDG FOR A VISUAL APCH TO RWY XXL AND EVENTUALLY CLRED FOR THE VISUAL APCH. THE ACFT WAS CONFIGURED FOR LNDG USING FLAPS 40 DEGS; INSIDE THE FAF WHEN THE CAPT NOTED VERBALLY AN INCREASE IN AIRSPD; A DECREASE IN PWR (AUTOTHROTTLES ON); AND THE ACFT PITCHING UP AND GAINING ALT. THE CAPT DECIDED TO EXECUTE A GAR AND TURN R TO A HDG OF 090 DEGS (AS BRIEFED BEFORE THE APCH) TO AVOID THE WX AT THEIR 12 O'CLOCK POS. AS THE PLANE WAS STARTING THE TURN; THE 'HEADWIND SHEAR' ALERT WAS ANNOUNCED OVER THE CAWS SYS. A FEW SECONDS LATER; AS AIRSPD BLED OFF QUICKLY; THE SYS CALLED OUT 'TAILWIND SHEAR.' WITH THE ACFT BELOW 1000 FT AGL; EMER PWR WAS SELECTED AND A STANDARD WINDSHEAR RECOVERY WAS PERFORMED MAINTAINING ALT WITH AIRSPD HOVERING AROUND THE 140-145 KT RANGE. EMER PWR WAS USED FOR A PERIOD OF 5-15 SECONDS UNTIL IT WAS DETERMINED THAT THE ACFT WAS CLR OF THE EVENT AND NORMAL CLB PWR WAS RESTORED. THE FADEC SWITCHES WERE RESET TO ALLOW FOR USE OF THE AUTOTHROTTLES AND THE ACFT PROCEEDED TO ZZZ1 FOR A LNDG. THE EVENT WAS CAUSED BY THE CONVECTIVE TSTM LOCATED N OF THE ARPT. THE ACFT WAS VMC; AND THE TWR RPTED STEADY STATE WINDS UNTIL JUST BEFORE THE INCIDENT OCCURRED.
Data retrieved from NASA's ASRS site as of May 2009 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.