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Attributes | |
ACN | 541910 |
Time | |
Date | 200203 |
Day | Sat |
Local Time Of Day | 1801 To 2400 |
Place | |
Locale Reference | airport : zzz.airport |
State Reference | US |
Altitude | agl single value : 0 |
Environment | |
Flight Conditions | Marginal |
Weather Elements | Snow |
Light | Night |
Aircraft 1 | |
Operator | common carrier : air carrier |
Make Model Name | Do 328 TP (Turboprop) |
Operating Under FAR Part | Part 121 |
Navigation In Use | other |
Flight Phase | ground : takeoff roll |
Flight Plan | IFR |
Person 1 | |
Affiliation | company : air carrier |
Function | flight crew : captain oversight : pic |
Qualification | pilot : atp pilot : instrument pilot : multi engine |
Experience | flight time last 90 days : 250 flight time total : 2200 flight time type : 250 |
ASRS Report | 541910 |
Person 2 | |
Affiliation | company : air carrier |
Function | flight crew : first officer |
Events | |
Anomaly | aircraft equipment problem : critical inflight encounter : weather other anomaly other |
Independent Detector | other flight crewa other flight crewb |
Resolutory Action | controller : provided flight assist flight crew : declared emergency flight crew : diverted to another airport |
Consequence | other |
Supplementary | |
Problem Areas | Weather Chart Or Publication Aircraft |
Primary Problem | Weather |
Narrative:
The aircraft shortly thereafter was covered with snow as a squall passed over the airport with heavy snow for approximately 20 mins. The crew planned for deicing in ZZZ1. At approximately XB41 the aircraft was pushed back from the gate, both engines were started and the aircraft was taxied to a remote deicing operation. Type I deicing was applied to the entire aircraft, followed by type iv on the wings and tail. This process took approximately 5 mins. The crew taxied the airplane onto the runway performing a pre-contamination takeoff check (no contamination of the representative surfaces noted) and all takeoff checklist items appropriate to the clearance. ZZZ1 tower cleared the airplane for takeoff, final checklist items were completed and the takeoff roll begun. Conditions at the time of takeoff were light snow, vertical visibility reported 500 ft and visibility greater than 1 mi. V-spds for the takeoff reflected wet contaminated takeoff data. As the aircraft accelerated, the PNF (the first officer) made appropriate calls of 80 KTS, V1, rotate. After receiving the rotate command, I (the captain) applied back pressure to the control column and noted that there was an opposing force. I quickly ensured the gust lock was seated in the appropriate down position and continued to apply abnormal back pressure to the elevator. After approximately 2-3 seconds, the column seemed to be relieved of all abnormal forces and the aircraft pitched normally. The aircraft was hand flown to approximately 4000 ft MSL while trying to note any abnormal control forces. The autoplt was then engaged and the aircraft continued to climb to a cruise altitude of FL230. The crew discussed the problem noting that there was no qrc or QRH for the unexplained condition upon rotation. There were no cas messages noted on the EICAS screen or flight control page. The crew contacted dispatch and maintenance control through ZZZ2 radio to discuss the current situation. It was agreed upon that the crew would perform an in-flight controllability and confign check. An emergency was also declared as a precaution to a possible flight control failure. The flight attendant was told to prepare the cabin for a possible evacuate/evacuation should the control problem reoccur. The crew put personal limitations of 5 degrees nose up and down, and 10 degrees bank left and right on the aircraft for the duration of the flight. After performing a controllability check of all controls (primary and secondary to include trim) and a confign check, the crew found no abnormalities in the response of the airplane to control inputs. The airplane was given radar vectors to runway 22L at ZZZ, where it would be met by crash and fire rescue vehicles and personnel. The aircraft landed uneventful and taxied to gate X where it was immediately downed for maintenance. The fact that the gust lock was found to be seated and no further mechanical abnormalities were experienced, leads me to believe that there was possible ice that may have inhibited movement of the elevator, but broke free as applied pressure continued to increase. Since the controls are checked free prior to takeoff, if ice was present, it must have been forward of the control surface and moved as airspeed/airflow increased. To prevent further occurrences, if ice was the cause then de-ice procedures must be especially thorough around hinge points of flight controls.
Original NASA ASRS Text
Title: A DORNIER 328 ON TKOF TO 110 FT HAD A MOMENTARY LOSS OF ELEVATOR CTL SUSPECTED CAUSE STABILIZER SNOW AND ICE SLIDING BACK INTO ELEVATOR GAP.
Narrative: THE ACFT SHORTLY THEREAFTER WAS COVERED WITH SNOW AS A SQUALL PASSED OVER THE ARPT WITH HVY SNOW FOR APPROX 20 MINS. THE CREW PLANNED FOR DEICING IN ZZZ1. AT APPROX XB41 THE ACFT WAS PUSHED BACK FROM THE GATE, BOTH ENGS WERE STARTED AND THE ACFT WAS TAXIED TO A REMOTE DEICING OP. TYPE I DEICING WAS APPLIED TO THE ENTIRE ACFT, FOLLOWED BY TYPE IV ON THE WINGS AND TAIL. THIS PROCESS TOOK APPROX 5 MINS. THE CREW TAXIED THE AIRPLANE ONTO THE RWY PERFORMING A PRE-CONTAMINATION TKOF CHK (NO CONTAMINATION OF THE REPRESENTATIVE SURFACES NOTED) AND ALL TKOF CHKLIST ITEMS APPROPRIATE TO THE CLRNC. ZZZ1 TWR CLRED THE AIRPLANE FOR TKOF, FINAL CHKLIST ITEMS WERE COMPLETED AND THE TKOF ROLL BEGUN. CONDITIONS AT THE TIME OF TKOF WERE LIGHT SNOW, VERT VISIBILITY RPTED 500 FT AND VISIBILITY GREATER THAN 1 MI. V-SPDS FOR THE TKOF REFLECTED WET CONTAMINATED TKOF DATA. AS THE ACFT ACCELERATED, THE PNF (THE FO) MADE APPROPRIATE CALLS OF 80 KTS, V1, ROTATE. AFTER RECEIVING THE ROTATE COMMAND, I (THE CAPT) APPLIED BACK PRESSURE TO THE CTL COLUMN AND NOTED THAT THERE WAS AN OPPOSING FORCE. I QUICKLY ENSURED THE GUST LOCK WAS SEATED IN THE APPROPRIATE DOWN POS AND CONTINUED TO APPLY ABNORMAL BACK PRESSURE TO THE ELEVATOR. AFTER APPROX 2-3 SECONDS, THE COLUMN SEEMED TO BE RELIEVED OF ALL ABNORMAL FORCES AND THE ACFT PITCHED NORMALLY. THE ACFT WAS HAND FLOWN TO APPROX 4000 FT MSL WHILE TRYING TO NOTE ANY ABNORMAL CTL FORCES. THE AUTOPLT WAS THEN ENGAGED AND THE ACFT CONTINUED TO CLB TO A CRUISE ALT OF FL230. THE CREW DISCUSSED THE PROB NOTING THAT THERE WAS NO QRC OR QRH FOR THE UNEXPLAINED CONDITION UPON ROTATION. THERE WERE NO CAS MESSAGES NOTED ON THE EICAS SCREEN OR FLT CTL PAGE. THE CREW CONTACTED DISPATCH AND MAINT CTL THROUGH ZZZ2 RADIO TO DISCUSS THE CURRENT SIT. IT WAS AGREED UPON THAT THE CREW WOULD PERFORM AN INFLT CONTROLLABILITY AND CONFIGN CHK. AN EMER WAS ALSO DECLARED AS A PRECAUTION TO A POSSIBLE FLT CTL FAILURE. THE FLT ATTENDANT WAS TOLD TO PREPARE THE CABIN FOR A POSSIBLE EVAC SHOULD THE CTL PROB REOCCUR. THE CREW PUT PERSONAL LIMITATIONS OF 5 DEGS NOSE UP AND DOWN, AND 10 DEGS BANK L AND R ON THE ACFT FOR THE DURATION OF THE FLT. AFTER PERFORMING A CONTROLLABILITY CHK OF ALL CTLS (PRIMARY AND SECONDARY TO INCLUDE TRIM) AND A CONFIGN CHK, THE CREW FOUND NO ABNORMALITIES IN THE RESPONSE OF THE AIRPLANE TO CTL INPUTS. THE AIRPLANE WAS GIVEN RADAR VECTORS TO RWY 22L AT ZZZ, WHERE IT WOULD BE MET BY CRASH AND FIRE RESCUE VEHICLES AND PERSONNEL. THE ACFT LANDED UNEVENTFUL AND TAXIED TO GATE X WHERE IT WAS IMMEDIATELY DOWNED FOR MAINT. THE FACT THAT THE GUST LOCK WAS FOUND TO BE SEATED AND NO FURTHER MECHANICAL ABNORMALITIES WERE EXPERIENCED, LEADS ME TO BELIEVE THAT THERE WAS POSSIBLE ICE THAT MAY HAVE INHIBITED MOVEMENT OF THE ELEVATOR, BUT BROKE FREE AS APPLIED PRESSURE CONTINUED TO INCREASE. SINCE THE CTLS ARE CHKED FREE PRIOR TO TKOF, IF ICE WAS PRESENT, IT MUST HAVE BEEN FORWARD OF THE CTL SURFACE AND MOVED AS AIRSPD/AIRFLOW INCREASED. TO PREVENT FURTHER OCCURRENCES, IF ICE WAS THE CAUSE THEN DE-ICE PROCS MUST BE ESPECIALLY THOROUGH AROUND HINGE POINTS OF FLT CTLS.
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.