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|
Attributes | |
ACN | 365471 |
Time | |
Date | 199704 |
Day | Sun |
Local Time Of Day | 1201 To 1800 |
Place | |
Locale Reference | airport : grb |
State Reference | WI |
Altitude | agl bound lower : 300 agl bound upper : 400 |
Environment | |
Flight Conditions | VMC |
Light | Daylight |
Aircraft 1 | |
Controlling Facilities | tower : grb |
Operator | common carrier : air carrier |
Make Model Name | DC-9 Undifferentiated or Other Model |
Operating Under FAR Part | Part 121 |
Flight Phase | descent : approach landing : go around |
Route In Use | approach : visual |
Flight Plan | IFR |
Person 1 | |
Affiliation | company : air carrier |
Function | flight crew : captain oversight : pic |
Qualification | pilot : instrument pilot : commercial pilot : cfi pilot : atp pilot : flight engineer |
Experience | flight time last 90 days : 150 flight time total : 11500 flight time type : 225 |
ASRS Report | 365471 |
Person 2 | |
Affiliation | company : air carrier |
Function | flight crew : first officer |
Qualification | pilot : commercial pilot : instrument |
Events | |
Anomaly | inflight encounter : weather |
Independent Detector | aircraft equipment other aircraft equipment : unspecified other flight crewa |
Resolutory Action | other |
Consequence | Other |
Supplementary | |
Primary Problem | Weather |
Air Traffic Incident | other |
Narrative:
Airspeed loss at 10 KTS (to vref) with no vertical deviation from GS resulted in 'red' windshear warning, this occurred at 300-400 ft AGL on approach to runway 24 grb. Initiated recovery per company policy except that by the time thrust level was at go around airplane horizontal and vertical performance was quite significantly positive so thrust levers were not advanced to the mechanical stops. Returned and landed without incident or further automated windshear warnings. Winds at time reported 230 degrees/25g35. Absent the automated windshear warning on the first approach, I would not have initiated a recovery. Aircraft performance indicators, while variable, were well within company limits for continuing the approach. I believe my failure to push thrust levers to the mechanical stops was a mistake and believe my inexperience on the airplane (my 7TH landing after IOE) to be a contributing factor. However, I would say that I am surprised, even shocked, at the low warning threshold for the warning system on this airplane. I believed, at the time, that I would have put the airplane and passenger in more danger by going to the mechanical thrust limits. After the fact, I think I may have been right in my judgement, but definitely not right in my lack of compliance with company policy. I still don't know which is the greater 'right' but have resolved to err on the side of policy in any future event.
Original NASA ASRS Text
Title: DC9 ACFT ON APCH ENCOUNTERED AIRSPD LOSS OF 10 KTS TO VREF. WINDSHEAR WARNING ACTIVATED AND RPTR CAPT EXECUTED GAR RECOVERY WITH THE EXCEPTION OF USING MAX THRUST. RPTR BELIEVED THE PERFORMANCE OF THE ACFT WAS ADEQUATE WITH REDUCED THRUST, BUT IT WAS NOT ACCORDING TO COMPANY SOP. RPTR ALSO SURPRISED BY THE LOW WARNING THRESHOLD OF THE WINDSHEAR WARNING.
Narrative: AIRSPD LOSS AT 10 KTS (TO VREF) WITH NO VERT DEV FROM GS RESULTED IN 'RED' WINDSHEAR WARNING, THIS OCCURRED AT 300-400 FT AGL ON APCH TO RWY 24 GRB. INITIATED RECOVERY PER COMPANY POLICY EXCEPT THAT BY THE TIME THRUST LEVEL WAS AT GAR AIRPLANE HORIZ AND VERT PERFORMANCE WAS QUITE SIGNIFICANTLY POSITIVE SO THRUST LEVERS WERE NOT ADVANCED TO THE MECHANICAL STOPS. RETURNED AND LANDED WITHOUT INCIDENT OR FURTHER AUTOMATED WINDSHEAR WARNINGS. WINDS AT TIME RPTED 230 DEGS/25G35. ABSENT THE AUTOMATED WINDSHEAR WARNING ON THE FIRST APCH, I WOULD NOT HAVE INITIATED A RECOVERY. ACFT PERFORMANCE INDICATORS, WHILE VARIABLE, WERE WELL WITHIN COMPANY LIMITS FOR CONTINUING THE APCH. I BELIEVE MY FAILURE TO PUSH THRUST LEVERS TO THE MECHANICAL STOPS WAS A MISTAKE AND BELIEVE MY INEXPERIENCE ON THE AIRPLANE (MY 7TH LNDG AFTER IOE) TO BE A CONTRIBUTING FACTOR. HOWEVER, I WOULD SAY THAT I AM SURPRISED, EVEN SHOCKED, AT THE LOW WARNING THRESHOLD FOR THE WARNING SYS ON THIS AIRPLANE. I BELIEVED, AT THE TIME, THAT I WOULD HAVE PUT THE AIRPLANE AND PAX IN MORE DANGER BY GOING TO THE MECHANICAL THRUST LIMITS. AFTER THE FACT, I THINK I MAY HAVE BEEN RIGHT IN MY JUDGEMENT, BUT DEFINITELY NOT RIGHT IN MY LACK OF COMPLIANCE WITH COMPANY POLICY. I STILL DON'T KNOW WHICH IS THE GREATER 'RIGHT' BUT HAVE RESOLVED TO ERR ON THE SIDE OF POLICY IN ANY FUTURE EVENT.
Data retrieved from NASA's ASRS site as of July 2007 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.