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Temporary loss of flight controls.
| Attributes | |
| ACN | 296074 |
| Time | |
| Date | 199502 |
| Day | Tue |
| Local Time Of Day | 1801 To 2400 |
| Place | |
| Locale Reference | airport : cgn |
| State Reference | FO |
| Altitude | msl bound lower : 4000 msl bound upper : 4000 |
| Environment | |
| Flight Conditions | VMC |
| Light | Night |
| Aircraft 1 | |
| Controlling Facilities | tracon : cgn |
| Operator | common carrier : air carrier |
| Make Model Name | B727-200 |
| Operating Under FAR Part | Part 121 |
| Flight Phase | descent : approach |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | company : air carrier |
| Function | flight crew : captain oversight : pic |
| Qualification | pilot : atp pilot : flight engineer |
| Experience | flight time last 90 days : 90 flight time total : 11000 flight time type : 9000 |
| ASRS Report | 296074 |
| Person 2 | |
| Affiliation | company : air carrier |
| Function | flight crew : first officer |
| Qualification | pilot : commercial pilot : instrument |
| Events | |
| Anomaly | aircraft equipment problem : critical other anomaly other |
| Independent Detector | aircraft equipment other aircraft equipment : unspecified other flight crewa |
| Resolutory Action | flight crew : returned to intended course or assigned course flight crew : regained aircraft control flight crew : overcame equipment problem |
| Consequence | Other |
| Supplementary | |
| Primary Problem | Flight Crew Human Performance |
| Air Traffic Incident | Pilot Deviation |
Narrative:
While slowing from 320 KTS to 180 KTS at 4600 ft the stabilizer 'out of trim' light illuminated, followed by the autoplt not being able to maintain altitude. The elevator indices showed a high displacement and were not able to compensate against the stabilizer position. The autoplt was disconnected on main electric, cruise and finally manual trims were tried but the stabilizer was frozen. Using the handles on the stabilizer trim wheel would not move the stabilizer. Completed the jammed flight control and jammed stabilizer landing checklist. Completed a landing on runway 14L at eddk after declaring an emergency. After parking at the ramp and consulting with maintenance, pulling the stabilizer brake release allowed the stabilizer to operate normally. After critiquing ourselves we discovered that the checklist stated it was 'complete' when it had additional items that included pulling the stabilizer brake release. The copilot and I had to both fly pitch on the aircraft and conducted an emergency for a poorly written checklist. Callback conversation with reporter revealed the following information: reporter stated the flight crew knew the significance of the stabilizer out of trim light' being on as they had slowed from 320 KTS to 180 KTS with the autoplt engaged. The elevator trim indicator was displaced full up when the autoplt was disengaged, at that time there was heavy nose down force on the control column. Both pilots were holding the control column to prevent loss of altitude. At the end of the checklist they were using for jammed stabilizer, is the item to pull the 'stabilizer brake release.' they discovered after the event if they had done that first the stabilizer would not have been fixed in 1 position. As a result of this incident, they have appealed to management of the air carrier to move the 'stabilizer brake release' item to be 1 of the first items in the checklist instead of the last item. Management has agreed to do this. They now have a greater awareness of the significance of what the 'stabilizer out of trim light,' means whenever it comes on. Supplemental information from acn 296644: on approach, beginning turn to final, autoplt disengaged, pilot reported heavy control forces, was unable to trim. Tried numerous times to trim using cruise and normal trim system, was unable. Captain continued approach, concerned that he'd better land before stick force couldn't be overcome. By this time, first officer was helping him oppose control forces. I checked, pulled and reset applicable circuit breaker's for trim system -- no help. We ran red tab v-list, declared emergency and landed. After uneventful landing, we realized our red tab v-lists dealing with stabilizer trim and flight control malfunctions were exceptionally vague and were misleading. We used the wrong checklist initially, then, due to time constraints, finished it prior to landing but didn't have time to examine the other checklists, or we would have been able to unlock the trim using stabilizer brake release. Captain filed flight crew safety report with company to address v-lists, was informed they were being revised due to similar complaints and observations.
Original NASA ASRS Text
Title: TEMPORARY LOSS OF FLT CTLS.
Narrative: WHILE SLOWING FROM 320 KTS TO 180 KTS AT 4600 FT THE STABILIZER 'OUT OF TRIM' LIGHT ILLUMINATED, FOLLOWED BY THE AUTOPLT NOT BEING ABLE TO MAINTAIN ALT. THE ELEVATOR INDICES SHOWED A HIGH DISPLACEMENT AND WERE NOT ABLE TO COMPENSATE AGAINST THE STABILIZER POS. THE AUTOPLT WAS DISCONNECTED ON MAIN ELECTRIC, CRUISE AND FINALLY MANUAL TRIMS WERE TRIED BUT THE STABILIZER WAS FROZEN. USING THE HANDLES ON THE STABILIZER TRIM WHEEL WOULD NOT MOVE THE STABILIZER. COMPLETED THE JAMMED FLT CTL AND JAMMED STABILIZER LNDG CHKLIST. COMPLETED A LNDG ON RWY 14L AT EDDK AFTER DECLARING AN EMER. AFTER PARKING AT THE RAMP AND CONSULTING WITH MAINT, PULLING THE STABILIZER BRAKE RELEASE ALLOWED THE STABILIZER TO OPERATE NORMALLY. AFTER CRITIQUING OURSELVES WE DISCOVERED THAT THE CHKLIST STATED IT WAS 'COMPLETE' WHEN IT HAD ADDITIONAL ITEMS THAT INCLUDED PULLING THE STABILIZER BRAKE RELEASE. THE COPLT AND I HAD TO BOTH FLY PITCH ON THE ACFT AND CONDUCTED AN EMER FOR A POORLY WRITTEN CHKLIST. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR STATED THE FLC KNEW THE SIGNIFICANCE OF THE STABILIZER OUT OF TRIM LIGHT' BEING ON AS THEY HAD SLOWED FROM 320 KTS TO 180 KTS WITH THE AUTOPLT ENGAGED. THE ELEVATOR TRIM INDICATOR WAS DISPLACED FULL UP WHEN THE AUTOPLT WAS DISENGAGED, AT THAT TIME THERE WAS HVY NOSE DOWN FORCE ON THE CTL COLUMN. BOTH PLTS WERE HOLDING THE CTL COLUMN TO PREVENT LOSS OF ALT. AT THE END OF THE CHKLIST THEY WERE USING FOR JAMMED STABILIZER, IS THE ITEM TO PULL THE 'STABILIZER BRAKE RELEASE.' THEY DISCOVERED AFTER THE EVENT IF THEY HAD DONE THAT FIRST THE STABILIZER WOULD NOT HAVE BEEN FIXED IN 1 POS. AS A RESULT OF THIS INCIDENT, THEY HAVE APPEALED TO MGMNT OF THE ACR TO MOVE THE 'STABILIZER BRAKE RELEASE' ITEM TO BE 1 OF THE FIRST ITEMS IN THE CHKLIST INSTEAD OF THE LAST ITEM. MGMNT HAS AGREED TO DO THIS. THEY NOW HAVE A GREATER AWARENESS OF THE SIGNIFICANCE OF WHAT THE 'STABILIZER OUT OF TRIM LIGHT,' MEANS WHENEVER IT COMES ON. SUPPLEMENTAL INFO FROM ACN 296644: ON APCH, BEGINNING TURN TO FINAL, AUTOPLT DISENGAGED, PLT RPTED HVY CTL FORCES, WAS UNABLE TO TRIM. TRIED NUMEROUS TIMES TO TRIM USING CRUISE AND NORMAL TRIM SYS, WAS UNABLE. CAPT CONTINUED APCH, CONCERNED THAT HE'D BETTER LAND BEFORE STICK FORCE COULDN'T BE OVERCOME. BY THIS TIME, FO WAS HELPING HIM OPPOSE CTL FORCES. I CHKED, PULLED AND RESET APPLICABLE CB'S FOR TRIM SYS -- NO HELP. WE RAN RED TAB V-LIST, DECLARED EMER AND LANDED. AFTER UNEVENTFUL LNDG, WE REALIZED OUR RED TAB V-LISTS DEALING WITH STABILIZER TRIM AND FLT CTL MALFUNCTIONS WERE EXCEPTIONALLY VAGUE AND WERE MISLEADING. WE USED THE WRONG CHKLIST INITIALLY, THEN, DUE TO TIME CONSTRAINTS, FINISHED IT PRIOR TO LNDG BUT DIDN'T HAVE TIME TO EXAMINE THE OTHER CHKLISTS, OR WE WOULD HAVE BEEN ABLE TO UNLOCK THE TRIM USING STABILIZER BRAKE RELEASE. CAPT FILED FLC SAFETY RPT WITH COMPANY TO ADDRESS V-LISTS, WAS INFORMED THEY WERE BEING REVISED DUE TO SIMILAR COMPLAINTS AND OBSERVATIONS.
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.