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|
Attributes | |
ACN | 1428989 |
Time | |
Date | 201703 |
Local Time Of Day | 0601-1200 |
Place | |
Locale Reference | ZZZZ.Airport |
State Reference | FO |
Environment | |
Light | Daylight |
Aircraft 1 | |
Make Model Name | Regional Jet 200 ER/LR (CRJ200) |
Operating Under FAR Part | Part 121 |
Flight Phase | Cruise |
Flight Plan | IFR |
Component | |
Aircraft Component | Aileron Trim System |
Person 1 | |
Function | Captain Pilot Flying |
Qualification | Flight Crew Air Transport Pilot (ATP) |
Events | |
Anomaly | Aircraft Equipment Problem Less Severe Deviation - Procedural Published Material / Policy |
Narrative:
While in cruise we observed what appeared to be anomalous indications of an out of trim condition with the autopilot engaged. While executing normal turns enroute; we occasionally observed both 'ap trim is lwd' (when turning left) and 'ap trim is rwd' (when turning right) caution messages; with the corresponding 'boxed-a' icon on the pfd. After several instances of this; I decided to disconnect the autopilot; in an effort to determine whether the indications were the result of a malfunctioning autopilot/trim system; or something else. While hand-flying; I noted the pressure required to actuate the ailerons was much greater than normal; though roll authority was well within an acceptable margin. The QRH was completed for the above-mentioned caution messages; and dispatch and maintenance control were notified of our experience; and of our intent to continue to ZZZZ. Approximately 10 minutes prior to landing I noted that the aileron control pressure rapidly returned to normal; to 'break free'; as I described in the discrepancy. The terminal descent; approach; and landing was without anomaly; and maintenance control was notified upon arrival at the gate.upon a detailed inspection by local contract mechanics in ZZZZ; it was found that the increased aileron control pressure was likely due to the main landing gear bay 'pan' (ZZZZ mechanic's term; not mine) rubbing against the aileron and aileron trim control cables. This was due to the fact that (according to the ZZZZ mechanic's description) the medium large transport bay 'pan' was not properly secured by mechanics during the previous inspection.whereas I cannot speak to the specific maintenance procedures and protocol under which the medium large transport bay 'pan' would be removed or unsecured; this event gives credence to the need to ensure that all panels - even those not readily observable - are secured by mechanics prior to signing-off inspections. In fact; the condition was undetectable during the pilots' preflight inspection and flight control checks (all appeared normal); only becoming manifest in high-speed cruise flight; when the local airflow apparently 'pushed' the panel up and against the control cables.it is my hope that this circumstance brings awareness to both mechanics and pilots alike; to strive to maximize situation awareness and to avoid complacency. In this case; a mechanic's inattention to detail offered the potential for unintended consequences.
Original NASA ASRS Text
Title: CRJ-200 Captain reported that with the autopilot engaged the aileron appeared to be out of trim. With the autopilot disengaged the ailerons were extremely heavy.
Narrative: While in cruise we observed what appeared to be anomalous indications of an out of trim condition with the autopilot engaged. While executing normal turns enroute; we occasionally observed both 'AP TRIM IS LWD' (when turning left) and 'AP TRIM IS RWD' (when turning right) caution messages; with the corresponding 'Boxed-A' icon on the PFD. After several instances of this; I decided to disconnect the autopilot; in an effort to determine whether the indications were the result of a malfunctioning autopilot/trim system; or something else. While hand-flying; I noted the pressure required to actuate the ailerons was much greater than normal; though roll authority was well within an acceptable margin. The QRH was completed for the above-mentioned caution messages; and Dispatch and Maintenance Control were notified of our experience; and of our intent to continue to ZZZZ. Approximately 10 minutes prior to landing I noted that the aileron control pressure rapidly returned to normal; to 'break free'; as I described in the discrepancy. The terminal descent; approach; and landing was without anomaly; and Maintenance Control was notified upon arrival at the gate.Upon a detailed inspection by local contract mechanics in ZZZZ; it was found that the increased aileron control pressure was likely due to the main landing gear bay 'pan' (ZZZZ mechanic's term; not mine) rubbing against the aileron and aileron trim control cables. This was due to the fact that (according to the ZZZZ mechanic's description) the MLG bay 'pan' was not properly secured by mechanics during the previous inspection.Whereas I cannot speak to the specific maintenance procedures and protocol under which the MLG bay 'pan' would be removed or unsecured; this event gives credence to the need to ensure that all panels - even those not readily observable - are secured by mechanics prior to signing-off inspections. In fact; the condition was undetectable during the pilots' preflight inspection and flight control checks (all appeared normal); only becoming manifest in high-speed cruise flight; when the local airflow apparently 'pushed' the panel up and against the control cables.It is my hope that this circumstance brings awareness to both mechanics and pilots alike; to strive to maximize situation awareness and to avoid complacency. In this case; a mechanic's inattention to detail offered the potential for unintended consequences.
Data retrieved from NASA's ASRS site 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.