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Pilot had frozen aileron control after flying above the freezing level in ZDV class east.
| Attributes | |
| ACN | 503717 |
| Time | |
| Date | 200103 |
| Day | Mon |
| Local Time Of Day | 0601 To 1200 |
| Place | |
| Locale Reference | navaid : gld.vortac |
| State Reference | KS |
| Altitude | msl single value : 13000 |
| Environment | |
| Flight Conditions | VMC |
| Weather Elements | other |
| Light | Daylight |
| Aircraft 1 | |
| Controlling Facilities | artcc : zdv.artcc |
| Operator | general aviation : personal |
| Make Model Name | PA-28 Cherokee Arrow IV |
| Operating Under FAR Part | Part 91 |
| Navigation In Use | other vortac |
| Flight Phase | cruise : level |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | other |
| Function | flight crew : single pilot |
| Qualification | pilot : instrument pilot : private |
| Experience | flight time last 90 days : 34 flight time total : 1090 flight time type : 750 |
| ASRS Report | 503717 |
| Person 2 | |
| Affiliation | government : faa |
| Function | controller : radar |
| Qualification | controller : radar |
| Events | |
| Anomaly | aircraft equipment problem : critical inflight encounter : weather inflight encounter other other anomaly other |
| Independent Detector | other flight crewa |
| Resolutory Action | flight crew : declared emergency none taken : detected after the fact other |
| Supplementary | |
| Problem Areas | Aircraft FAA |
| Primary Problem | Aircraft |
Narrative:
During preflight removed a fair amount of frost from tops of wings (none on body due to canvas cover). Conducted full preflight, including check of all control surface movement, with no problems. Temperature was approximately 32 degree F. Excellent VFR day (no clouds at all) with 10-20 NM visibility. Climbed directly to 13000 ft (temperature-5 degree C). After 5-10 min at 13000 ft noticed controls were 'frozen'-could not turn more than 5 degree left or right. Believe residual moisture on wings had melted under bright sun and drained into void space created by aileron flap seals and froze. Contacted ATC and declared emergency. Requested descent and to 10000 ft to unfreeze controls. After 2-3 min at 10000 ft (+ 2 degree C) the controls unfroze. Verified normal operation of controls and then cancelled emergency with denver center. This is the 4TH occurrence where I have had ailerons freeze up after climbing above freezing level due to residual water collecting in void space made by after market aileron seals. Callback conversation with reporter revealed the following information: the aircraft was equipped with after market aileron seals by laminer flow systems at st. Thomas, vi. The stc number is SA1580SO. Pilot suspects that the moisture drain for the seals is not proper. This allows trapped moisture to freeze, which jams the aileron. The pilot had this happen on 4 other occasions.
Original NASA ASRS Text
Title: PLT HAD FROZEN AILERON CTL AFTER FLYING ABOVE THE FREEZING LEVEL IN ZDV CLASS E.
Narrative: DURING PREFLT REMOVED A FAIR AMOUNT OF FROST FROM TOPS OF WINGS (NONE ON BODY DUE TO CANVAS COVER). CONDUCTED FULL PREFLT, INCLUDING CHK OF ALL CTL SURFACE MOVEMENT, WITH NO PROBS. TEMP WAS APPROX 32 DEG F. EXCELLENT VFR DAY (NO CLOUDS AT ALL) WITH 10-20 NM VIS. CLBED DIRECTLY TO 13000 FT (TEMP-5 DEG C). AFTER 5-10 MIN AT 13000 FT NOTICED CTLS WERE 'FROZEN'-COULD NOT TURN MORE THAN 5 DEG L OR R. BELIEVE RESIDUAL MOISTURE ON WINGS HAD MELTED UNDER BRIGHT SUN AND DRAINED INTO VOID SPACE CREATED BY AILERON FLAP SEALS AND FROZE. CONTACTED ATC AND DECLARED EMER. REQUESTED DSCNT AND TO 10000 FT TO UNFREEZE CTLS. AFTER 2-3 MIN AT 10000 FT (+ 2 DEG C) THE CTLS UNFROZE. VERIFIED NORMAL OP OF CTLS AND THEN CANCELLED EMER WITH DENVER CENTER. THIS IS THE 4TH OCCURRENCE WHERE I HAVE HAD AILERONS FREEZE UP AFTER CLBING ABOVE FREEZING LEVEL DUE TO RESIDUAL WATER COLLECTING IN VOID SPACE MADE BY AFTER MARKET AILERON SEALS. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE ACFT WAS EQUIPPED WITH AFTER MARKET AILERON SEALS BY LAMINER FLOW SYSTEMS AT ST. THOMAS, VI. THE STC NUMBER IS SA1580SO. PLT SUSPECTS THAT THE MOISTURE DRAIN FOR THE SEALS IS NOT PROPER. THIS ALLOWS TRAPPED MOISTURE TO FREEZE, WHICH JAMS THE AILERON. THE PLT HAD THIS HAPPEN ON 4 OTHER OCCASIONS.
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.