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|
Attributes | |
ACN | 400446 |
Time | |
Date | 199804 |
Day | Tue |
Local Time Of Day | 0601 To 1200 |
Place | |
Locale Reference | airport : lex |
State Reference | KY |
Altitude | agl bound lower : 0 agl bound upper : 0 |
Environment | |
Flight Conditions | VMC |
Light | Daylight |
Aircraft 1 | |
Operator | common carrier : air carrier |
Make Model Name | Jetstream 41 |
Operating Under FAR Part | Part 135 |
Navigation In Use | Other |
Flight Phase | ground other : taxi |
Flight Plan | IFR |
Person 1 | |
Affiliation | company : air carrier |
Function | flight crew : captain oversight : pic |
Qualification | pilot : cfi pilot : atp |
Experience | flight time last 90 days : 54 flight time total : 4453 flight time type : 1385 |
ASRS Report | 400446 |
Person 2 | |
Affiliation | company : air carrier |
Function | flight crew : first officer |
Qualification | pilot : instrument pilot : commercial |
Events | |
Anomaly | aircraft equipment problem : critical non adherence : published procedure non adherence : far other anomaly other |
Independent Detector | other flight crewa |
Resolutory Action | none taken : anomaly accepted |
Consequence | Other |
Supplementary | |
Primary Problem | Aircraft |
Air Traffic Incident | Pilot Deviation |
Narrative:
The event can best be described as a system abnormality. During taxi-out from lex we performed morning first flight checks. While completing the stall system check, the first officer reported that upon checking the right stick shaker, the stick push function also seemed to activate but not with full pusher force. When the stick push function was tested a noticeable difference in pusher force was observed. The first officer and I agreed that the system outputs were tested and functioning. We departed and continued to the destination (stl) without incident. After arrival during taxi-in, we tested the system again and found the same result. After shutdown, maintenance was consulted and the event recorded in the aircraft maintenance logbook. My concern in the matter after having applied a great deal of afterthought is that this irregularity should have been 'written up' at the outstation and maintenance action sought there. Instead of looking at the details for fulfilling test requirements (allowing mission completion), this event should have been taken at face value as an irregularity and the system considered partially unairworthy. Callback conversation with reporter revealed the following information: the reporter stated the aircraft was a BAE4100 and the stall warning and the stall protection system are separate system on the left and right control columns. The reporter said when test prior to takeoff the first officer's stick shaker operated ok but the stick push function force was low. The reporter said it was decided to go as both system did test. The reporter stated after a test at trip termination it was clear the stick push function was not normal and was written up for maintenance to correct.
Original NASA ASRS Text
Title: A BAE 4100 WAS OPERATED WITH THE FO'S STALL PROTECTION STICK PUSH FUNCTION FORCE LOW AND OUT OF LIMITS.
Narrative: THE EVENT CAN BEST BE DESCRIBED AS A SYSTEM ABNORMALITY. DURING TAXI-OUT FROM LEX WE PERFORMED MORNING FIRST FLT CHECKS. WHILE COMPLETING THE STALL SYSTEM CHECK, THE FO REPORTED THAT UPON CHECKING THE R STICK SHAKER, THE STICK PUSH FUNCTION ALSO SEEMED TO ACTIVATE BUT NOT WITH FULL PUSHER FORCE. WHEN THE STICK PUSH FUNCTION WAS TESTED A NOTICEABLE DIFFERENCE IN PUSHER FORCE WAS OBSERVED. THE FO AND I AGREED THAT THE SYSTEM OUTPUTS WERE TESTED AND FUNCTIONING. WE DEPARTED AND CONTINUED TO THE DESTINATION (STL) WITHOUT INCIDENT. AFTER ARRIVAL DURING TAXI-IN, WE TESTED THE SYSTEM AGAIN AND FOUND THE SAME RESULT. AFTER SHUTDOWN, MAINT WAS CONSULTED AND THE EVENT RECORDED IN THE ACFT MAINT LOGBOOK. MY CONCERN IN THE MATTER AFTER HAVING APPLIED A GREAT DEAL OF AFTERTHOUGHT IS THAT THIS IRREGULARITY SHOULD HAVE BEEN 'WRITTEN UP' AT THE OUTSTATION AND MAINT ACTION SOUGHT THERE. INSTEAD OF LOOKING AT THE DETAILS FOR FULFILLING TEST REQUIREMENTS (ALLOWING MISSION COMPLETION), THIS EVENT SHOULD HAVE BEEN TAKEN AT FACE VALUE AS AN IRREGULARITY AND THE SYSTEM CONSIDERED PARTIALLY UNAIRWORTHY. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THE ACFT WAS A BAE4100 AND THE STALL WARNING AND THE STALL PROTECTION SYS ARE SEPARATE SYS ON THE L AND R CTL COLUMNS. THE RPTR SAID WHEN TEST PRIOR TO TKOF THE FO'S STICK SHAKER OPERATED OK BUT THE STICK PUSH FUNCTION FORCE WAS LOW. THE RPTR SAID IT WAS DECIDED TO GO AS BOTH SYS DID TEST. THE RPTR STATED AFTER A TEST AT TRIP TERMINATION IT WAS CLR THE STICK PUSH FUNCTION WAS NOT NORMAL AND WAS WRITTEN UP FOR MAINT TO CORRECT.
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.