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Attributes | |
ACN | 681938 |
Time | |
Date | 200512 |
Local Time Of Day | 1201 To 1800 |
Place | |
Locale Reference | airport : zzz.airport |
State Reference | US |
Altitude | msl bound lower : 5000 msl bound upper : 6000 |
Environment | |
Flight Conditions | VMC |
Light | Night |
Aircraft 1 | |
Controlling Facilities | tracon : zzz.tracon |
Operator | common carrier : air carrier |
Make Model Name | Regional Jet 700 ER&LR |
Operating Under FAR Part | Part 121 |
Flight Phase | climbout : initial |
Flight Plan | IFR |
Person 1 | |
Affiliation | company : air carrier |
Function | flight crew : captain oversight : pic |
Experience | flight time last 90 days : 232 flight time total : 30000 flight time type : 13000 |
ASRS Report | 681938 |
Person 2 | |
Affiliation | company : air carrier |
Function | flight crew : first officer |
Events | |
Anomaly | aircraft equipment problem : critical altitude deviation : overshoot non adherence : clearance other anomaly |
Independent Detector | other flight crewa other flight crewb |
Resolutory Action | flight crew : overcame equipment problem flight crew : regained aircraft control flight crew : declared emergency |
Consequence | other other |
Supplementary | |
Problem Areas | Aircraft |
Primary Problem | Aircraft |
Narrative:
Flight departed runway 32L with assigned initial altitude of 5000 ft and heading of 270 degrees. During climb out; #2 chan stabilizer status message noticed and was attempted to re-engaged. Push light was not illuminated prior to attempt. Captain's autoplt disengage switch did not respond nor did captain's stabilizer trim disconnect switch. Attempt to disconnect at first officer's yoke resulted in pitch up moments requiring excessive forward pressure to neutralize pitch. Autoplt disconnect aurals were unable to be silenced from yoke or fcp. First officer trim wheel was operational at this time and he was able to silence aurals from (with) his yoke autoplt disconnect. Control was xferred to first officer for trim control. During the anomaly and subsequent noise in cockpit I was unable to clearly hear ATC commands. The forces required to neutralize the climb in such a manner as to not injure occupants and negative G's; the aircraft required an excursion from 5000 ft to almost 6000 ft. The first officer had declared an emergency (which I never heard) because he sensed an uncontrollable aircraft about the longitudinal axis. ATC was subsequently advised the act was indeed under control. During this time contact was established with cabin crew and we (flight crew) were advised the passenger had not experienced any unsettling forces. I resumed command of the aircraft and exercised all axis for positive control and trim control. The stabilizers and mach trim engagement indicated lights out and operational. ATC was advised the flight would continue. The autoplt would no longer engage from either seat control. The flight director was operational and correct. I hand flew all phases of flight until normal readouts and responses. Maintenance control and chief pilot were consulted. Callback conversation with reporter revealed the following information: reporter stated that he believes the high engine power setting and light aircraft contributed to an unusually high nose pitch attitude necessary to control airspeed. The aircraft has an automatic trim system that the reporter believes approached its limits. The EICAS indicated a right stabilizer fault but the corresponding panel light did not illuminate. The aircraft's elevator trim was essentially uncontrollable from the captain's yoke and so the first officer took control and was able to disconnect stabilizer trim. One contributing factor to the confusion was the crew's inability to silence the warning horn and because of the loud warning noise unable to communicate internally or hear radio xmissions.
Original NASA ASRS Text
Title: A LIGHTLY LOADED CRJ700 DEPARTED AT FULL PWR CLBING RAPIDLY. THE CAPT'S YOKE COULD NOT INPUT PITCH TO LOWER THE NOSE.
Narrative: FLT DEPARTED RWY 32L WITH ASSIGNED INITIAL ALT OF 5000 FT AND HDG OF 270 DEGS. DURING CLBOUT; #2 CHAN STABILIZER STATUS MESSAGE NOTICED AND WAS ATTEMPTED TO RE-ENGAGED. PUSH LIGHT WAS NOT ILLUMINATED PRIOR TO ATTEMPT. CAPT'S AUTOPLT DISENGAGE SWITCH DID NOT RESPOND NOR DID CAPT'S STABILIZER TRIM DISCONNECT SWITCH. ATTEMPT TO DISCONNECT AT FO'S YOKE RESULTED IN PITCH UP MOMENTS REQUIRING EXCESSIVE FORWARD PRESSURE TO NEUTRALIZE PITCH. AUTOPLT DISCONNECT AURALS WERE UNABLE TO BE SILENCED FROM YOKE OR FCP. FO TRIM WHEEL WAS OPERATIONAL AT THIS TIME AND HE WAS ABLE TO SILENCE AURALS FROM (WITH) HIS YOKE AUTOPLT DISCONNECT. CTL WAS XFERRED TO FO FOR TRIM CTL. DURING THE ANOMALY AND SUBSEQUENT NOISE IN COCKPIT I WAS UNABLE TO CLRLY HEAR ATC COMMANDS. THE FORCES REQUIRED TO NEUTRALIZE THE CLB IN SUCH A MANNER AS TO NOT INJURE OCCUPANTS AND NEGATIVE G'S; THE ACFT REQUIRED AN EXCURSION FROM 5000 FT TO ALMOST 6000 FT. THE FO HAD DECLARED AN EMER (WHICH I NEVER HEARD) BECAUSE HE SENSED AN UNCTLABLE ACFT ABOUT THE LONGITUDINAL AXIS. ATC WAS SUBSEQUENTLY ADVISED THE ACT WAS INDEED UNDER CTL. DURING THIS TIME CONTACT WAS ESTABLISHED WITH CABIN CREW AND WE (FLT CREW) WERE ADVISED THE PAX HAD NOT EXPERIENCED ANY UNSETTLING FORCES. I RESUMED COMMAND OF THE ACFT AND EXERCISED ALL AXIS FOR POSITIVE CTL AND TRIM CTL. THE STABILIZERS AND MACH TRIM ENGAGEMENT INDICATED LIGHTS OUT AND OPERATIONAL. ATC WAS ADVISED THE FLT WOULD CONTINUE. THE AUTOPLT WOULD NO LONGER ENGAGE FROM EITHER SEAT CTL. THE FLT DIRECTOR WAS OPERATIONAL AND CORRECT. I HAND FLEW ALL PHASES OF FLT UNTIL NORMAL READOUTS AND RESPONSES. MAINT CTL AND CHIEF PLT WERE CONSULTED. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR STATED THAT HE BELIEVES THE HIGH ENG PWR SETTING AND LIGHT ACFT CONTRIBUTED TO AN UNUSUALLY HIGH NOSE PITCH ATTITUDE NECESSARY TO CTL AIRSPD. THE ACFT HAS AN AUTOMATIC TRIM SYS THAT THE RPTR BELIEVES APCHED ITS LIMITS. THE EICAS INDICATED A R STABILIZER FAULT BUT THE CORRESPONDING PANEL LIGHT DID NOT ILLUMINATE. THE ACFT'S ELEVATOR TRIM WAS ESSENTIALLY UNCTLABLE FROM THE CAPT'S YOKE AND SO THE FO TOOK CTL AND WAS ABLE TO DISCONNECT STABILIZER TRIM. ONE CONTRIBUTING FACTOR TO THE CONFUSION WAS THE CREW'S INABILITY TO SILENCE THE WARNING HORN AND BECAUSE OF THE LOUD WARNING NOISE UNABLE TO COMMUNICATE INTERNALLY OR HEAR RADIO XMISSIONS.
Data retrieved from NASA's ASRS site as of January 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.