When the pilot of an small aircraft sel climbed through the freezing level the elevator trim became ...

Attributes
ACN	326171
Time
Date	199601
Day	Wed
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : pae
State Reference	WA
Altitude	msl bound lower : 3000 msl bound upper : 5000
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Controlling Facilities	artcc : zse tower : mci
Operator	general aviation : personal
Make Model Name	Skylane 182/RG Turbo Skylane/RG
Operating Under FAR Part	Part 91
Flight Phase	descent other
Route In Use	enroute : on vectors
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : instrument pilot : commercial pilot : cfi
Experience	flight time last 90 days : 82 flight time total : 1568 flight time type : 200
ASRS Report	326171
Person 2
Affiliation	government : faa
Function	controller : approach
Qualification	controller : radar
Events
Anomaly	aircraft equipment problem : critical inflight encounter : weather other anomaly other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : unspecified other flight crewa
Resolutory Action	aircraft : equipment problem dissipated flight crew : overcame equipment problem other
Consequence	Other
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other

Narrative:

I planned a night training flight from rnt to pae and return, on an instrument flight plan. The surface temperature was 39 degrees F and there was no precipitation, but the airframe and ground were wet due to rain earlier in the day. The forecast freezing level was 2000-3000 ft. I was not concerned about in-flight icing, since my route of flight was clear. After reaching my assigned altitude, I trimmed the airplane for 130 KTS and made a PIREP. The outside air temperature was 29 degrees F. I attempted to make a minor adjustment to trim and found the elevator trim frozen, the wheel wouldn't move. I was now talking to ZSE, was told I was #3 for the approach, and told to climb and maintain 5000 ft. Center then told me to maintain 90 KTS. To comply, I reduced power and lowered the gear. Without the trim this results in a very nose heavy airplane that takes a while to decelerate. Center then gave me vectors to the localizer, and a clearance for the approach, including 'maintain 3000 ft until established,' 3 mi from the OM. During descent from 5000 ft to 3000 ft it was difficult to maintain 90 KTS, since even a slight relaxation in back pressure allowed very rapid acceleration of the airplane. When center cleared me for the frequency change to tower they again told me to maintain 90 KTS. I told them I'd try. I was concentrating so hard on doing this that it didn't occur to me to tell them the trim had frozen and I was exceeding the 10 KT tolerance. From the OM inbound I was able to do this, since I had gotten the airplane stabilized. The trim unfroze at about 1000 ft, and I asked for a clearance back to rnt at 2000 ft and had no problems. (If this had happened in IMC it would have been a real handful since my GS failed at the OM.) a leak at the base of the rear window has been sealed.

Original NASA ASRS Text

Title: WHEN THE PLT OF AN SMA SEL CLBED THROUGH THE FREEZING LEVEL THE ELEVATOR TRIM BECAME STUCK RESULTING IN AN AIRSPD DEV DURING DSCNT FOR APCH. THE TRIM BECAME UNSTUCK WHEN THE ACFT RETURNED BELOW THE FREEZING LEVEL.

Narrative: I PLANNED A NIGHT TRAINING FLT FROM RNT TO PAE AND RETURN, ON AN INST FLT PLAN. THE SURFACE TEMP WAS 39 DEGS F AND THERE WAS NO PRECIP, BUT THE AIRFRAME AND GND WERE WET DUE TO RAIN EARLIER IN THE DAY. THE FORECAST FREEZING LEVEL WAS 2000-3000 FT. I WAS NOT CONCERNED ABOUT INFLT ICING, SINCE MY RTE OF FLT WAS CLR. AFTER REACHING MY ASSIGNED ALT, I TRIMMED THE AIRPLANE FOR 130 KTS AND MADE A PIREP. THE OUTSIDE AIR TEMP WAS 29 DEGS F. I ATTEMPTED TO MAKE A MINOR ADJUSTMENT TO TRIM AND FOUND THE ELEVATOR TRIM FROZEN, THE WHEEL WOULDN'T MOVE. I WAS NOW TALKING TO ZSE, WAS TOLD I WAS #3 FOR THE APCH, AND TOLD TO CLB AND MAINTAIN 5000 FT. CTR THEN TOLD ME TO MAINTAIN 90 KTS. TO COMPLY, I REDUCED PWR AND LOWERED THE GEAR. WITHOUT THE TRIM THIS RESULTS IN A VERY NOSE HVY AIRPLANE THAT TAKES A WHILE TO DECELERATE. CTR THEN GAVE ME VECTORS TO THE LOC, AND A CLRNC FOR THE APCH, INCLUDING 'MAINTAIN 3000 FT UNTIL ESTABLISHED,' 3 MI FROM THE OM. DURING DSCNT FROM 5000 FT TO 3000 FT IT WAS DIFFICULT TO MAINTAIN 90 KTS, SINCE EVEN A SLIGHT RELAXATION IN BACK PRESSURE ALLOWED VERY RAPID ACCELERATION OF THE AIRPLANE. WHEN CTR CLRED ME FOR THE FREQ CHANGE TO TWR THEY AGAIN TOLD ME TO MAINTAIN 90 KTS. I TOLD THEM I'D TRY. I WAS CONCENTRATING SO HARD ON DOING THIS THAT IT DIDN'T OCCUR TO ME TO TELL THEM THE TRIM HAD FROZEN AND I WAS EXCEEDING THE 10 KT TOLERANCE. FROM THE OM INBOUND I WAS ABLE TO DO THIS, SINCE I HAD GOTTEN THE AIRPLANE STABILIZED. THE TRIM UNFROZE AT ABOUT 1000 FT, AND I ASKED FOR A CLRNC BACK TO RNT AT 2000 FT AND HAD NO PROBS. (IF THIS HAD HAPPENED IN IMC IT WOULD HAVE BEEN A REAL HANDFUL SINCE MY GS FAILED AT THE OM.) A LEAK AT THE BASE OF THE REAR WINDOW HAS BEEN SEALED.

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.

When the pilot of an small aircraft sel climbed through the freezing level the elevator trim became stuck resulting in an airspeed deviation during descent for approach. The trim became unstuck when the aircraft returned below the freezing level.