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Pilot of small aircraft, at 8000' MSL with temperature below freezing in WX, encountered icing conditions--one fourth inch of ice formed on aircraft and pilot was unable to hold airspeed and altitude--descended.
| Attributes | |
| ACN | 178105 |
| Time | |
| Date | 199105 |
| Day | Sun |
| Local Time Of Day | 1201 To 1800 |
| Place | |
| Locale Reference | atc facility : sea |
| State Reference | WA |
| Altitude | msl bound lower : 4500 msl bound upper : 8000 |
| Environment | |
| Flight Conditions | IMC |
| Light | Daylight |
| Aircraft 1 | |
| Operator | common carrier : air carrier |
| Make Model Name | Small Aircraft, High Wing, 1 Eng, Fixed Gear |
| Flight Phase | cruise other |
| Route In Use | enroute airway : v2 |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | Other |
| Function | flight crew : single pilot |
| Qualification | pilot : instrument pilot : commercial |
| Experience | flight time last 90 days : 40 flight time total : 1900 |
| ASRS Report | 178105 |
| Person 2 | |
| Affiliation | government : faa |
| Function | controller : radar |
| Qualification | controller : radar |
| Events | |
| Anomaly | altitude deviation : excursion from assigned altitude inflight encounter : weather non adherence : clearance other anomaly |
| Independent Detector | other other : unspecified cockpit |
| Resolutory Action | flight crew : regained aircraft control |
| Consequence | Other |
| Supplementary | |
| Primary Problem | Weather |
| Air Traffic Incident | other |
Narrative:
While in cruise at 8000', the outside air temperature dropped from +5 degrees F to -2 degrees F, and 1/4' of rime ice formed on the outside of the aircraft. In order to attempt to maintain altitude, it was necessary to reduce airspeed to 75 KTS. But the aircraft was still descending at 200 FPM. This continued until the ice came off at 4500' and was in VFR conditions again. Prior to entering IMC conditions, I tried several times to request a higher altitude (10000'), but was unable due to, first, traffic at that altitude, then terrain interference with communications. This situation occurred because I did not exercise my emergency authority soon enough and do a 180 degree turn before entering the clouds, even though the OAT was above freezing. I feel that in order to prevent a recurrence that I will make a greater margin of safety available in the future.
Original NASA ASRS Text
Title: PLT OF SMA, AT 8000' MSL WITH TEMPERATURE BELOW FREEZING IN WX, ENCOUNTERED ICING CONDITIONS--ONE FOURTH INCH OF ICE FORMED ON ACFT AND PLT WAS UNABLE TO HOLD AIRSPEED AND ALT--DESCENDED.
Narrative: WHILE IN CRUISE AT 8000', THE OUTSIDE AIR TEMP DROPPED FROM +5 DEGS F TO -2 DEGS F, AND 1/4' OF RIME ICE FORMED ON THE OUTSIDE OF THE ACFT. IN ORDER TO ATTEMPT TO MAINTAIN ALT, IT WAS NECESSARY TO REDUCE AIRSPD TO 75 KTS. BUT THE ACFT WAS STILL DSNDING AT 200 FPM. THIS CONTINUED UNTIL THE ICE CAME OFF AT 4500' AND WAS IN VFR CONDITIONS AGAIN. PRIOR TO ENTERING IMC CONDITIONS, I TRIED SEVERAL TIMES TO REQUEST A HIGHER ALT (10000'), BUT WAS UNABLE DUE TO, FIRST, TFC AT THAT ALT, THEN TERRAIN INTERFERENCE WITH COMS. THIS SITUATION OCCURRED BECAUSE I DID NOT EXERCISE MY EMER AUTHORITY SOON ENOUGH AND DO A 180 DEG TURN BEFORE ENTERING THE CLOUDS, EVEN THOUGH THE OAT WAS ABOVE FREEZING. I FEEL THAT IN ORDER TO PREVENT A RECURRENCE THAT I WILL MAKE A GREATER MARGIN OF SAFETY AVAILABLE IN THE FUTURE.
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.