Narrative:

Climbing en route from mem to hou through layered clouds, we entered a cloud deck approaching FL200. No icing was reported or anticipated in area. Ram air temperature at FL200 was +10 degree C. We heard increasing airflow noise and visually checked for icing. Ram air temperature indicated +8 degree C and inspection revealed rapid ice build up in wiper assembly area. We turned on #2 engine anti-ice and airfoil anti-ice and waited approximately 1 min to be sure engine remained stable. During that time ice build up progressed to approximately 2 1/2 -3 inches. #2 engine remained stable and the #1 engine anti-ice was turned on. At that time we heard 2 pops and noticed #2 EPR gauge fluctuations. All other engine indications were normal. Approximately 30 seconds later we heard 1 more pop but it was not associated with any abnormal indications. We broke out on top at FL240 and continued climb to ATC assigned FL260. Engines remained stable. In cruise we compared previous engine monitors with that of current readings. Readings were consistent with previous data. We continued to hou with an uneventful flight and landing. We requested maintenance and inspection revealed damage to at least first stage compressor blades of both engines. The maintenance action was a double engine change. In 25 yrs of flying, I have never incurred such rapid ice accumulation. We were further surprised as the temperature in our environment was warmer than that normally associated with icing conditions. Perhaps in temperatures higher than those of present guidelines in the event of atmospheric conditions such as we encountered.

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Original NASA ASRS Text

Title: ICE INGESTION RESULTS IN COMPRESSOR BLADE DAMAGE, DOUBLE ENG CHANGE.

Narrative: CLBING ENRTE FROM MEM TO HOU THROUGH LAYERED CLOUDS, WE ENTERED A CLOUD DECK APCHING FL200. NO ICING WAS RPTED OR ANTICIPATED IN AREA. RAM AIR TEMP AT FL200 WAS +10 DEG C. WE HEARD INCREASING AIRFLOW NOISE AND VISUALLY CHKED FOR ICING. RAM AIR TEMP INDICATED +8 DEG C AND INSPECTION REVEALED RAPID ICE BUILD UP IN WIPER ASSEMBLY AREA. WE TURNED ON #2 ENG ANTI-ICE AND AIRFOIL ANTI-ICE AND WAITED APPROX 1 MIN TO BE SURE ENG REMAINED STABLE. DURING THAT TIME ICE BUILD UP PROGRESSED TO APPROX 2 1/2 -3 INCHES. #2 ENG REMAINED STABLE AND THE #1 ENG ANTI-ICE WAS TURNED ON. AT THAT TIME WE HEARD 2 POPS AND NOTICED #2 EPR GAUGE FLUCTUATIONS. ALL OTHER ENG INDICATIONS WERE NORMAL. APPROX 30 SECONDS LATER WE HEARD 1 MORE POP BUT IT WAS NOT ASSOCIATED WITH ANY ABNORMAL INDICATIONS. WE BROKE OUT ON TOP AT FL240 AND CONTINUED CLB TO ATC ASSIGNED FL260. ENGS REMAINED STABLE. IN CRUISE WE COMPARED PREVIOUS ENG MONITORS WITH THAT OF CURRENT READINGS. READINGS WERE CONSISTENT WITH PREVIOUS DATA. WE CONTINUED TO HOU WITH AN UNEVENTFUL FLT AND LNDG. WE REQUESTED MAINT AND INSPECTION REVEALED DAMAGE TO AT LEAST FIRST STAGE COMPRESSOR BLADES OF BOTH ENGS. THE MAINT ACTION WAS A DOUBLE ENG CHANGE. IN 25 YRS OF FLYING, I HAVE NEVER INCURRED SUCH RAPID ICE ACCUMULATION. WE WERE FURTHER SURPRISED AS THE TEMP IN OUR ENVIRONMENT WAS WARMER THAN THAT NORMALLY ASSOCIATED WITH ICING CONDITIONS. PERHAPS IN TEMPS HIGHER THAN THOSE OF PRESENT GUIDELINES IN THE EVENT OF ATMOSPHERIC CONDITIONS SUCH AS WE ENCOUNTERED.

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.