C-172 encounters in-flight icing during a night operation cross country training flight.

Attributes
ACN	303032
Time
Date	199504
Day	Sun
Local Time Of Day	1801 To 2400
Place
Locale Reference	atc facility : cmi
State Reference	IL
Altitude	msl bound lower : 2500 msl bound upper : 12000
Environment
Flight Conditions	IMC
Light	Night
Aircraft 1
Controlling Facilities	tracon : huf
Operator	general aviation : instructional
Make Model Name	Skyhawk 172/Cutlass 172
Operating Under FAR Part	Part 91
Flight Phase	cruise other descent other
Route In Use	enroute airway : zid
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : single pilot instruction : trainee
Qualification	pilot : private
Experience	flight time last 90 days : 31 flight time total : 100 flight time type : 80
ASRS Report	303032
Person 2
Affiliation	Other
Function	instruction : instructor oversight : pic
Qualification	pilot : commercial pilot : cfi pilot : instrument
Events
Anomaly	inflight encounter other
Independent Detector	other flight crewa
Resolutory Action	flight crew : exited adverse environment
Consequence	Other
Supplementary
Primary Problem	Weather
Air Traffic Incident	other

Narrative:

I was flying as PIC as an IFR student, with my instructor in the right seat. En route at 8000 ft from nashville, we saw the cloud tops slowly rise from 6000-7000 ft on up to 8000 ft MSL. We asked for, and were given, 10000 ft as a cruising altitude. The clouds continued their gentle upslope, and we began to brush them again. We asked for 11000 ft, then later 12000 ft from ATC. As we began to penetrate the clouds at 12000 ft, we both noticed ice (rime) forming on the wing struts. By the time we were cleared to 8000 ft (to attempt to descend out of the icing environment), we were picking up moderate rime ice. Descending toward 8000 ft, we notified ATC that the icing was moderate to severe rime, and requested 3000 ft. Upon reaching 3000 ft (and later 2500 ft), our 1/2 inch ice on the wings fell off gradually. Control of the aircraft was never lost, no regulations were broken, and no hazard to ourselves or other aircraft was experienced. My actions were consistent with prescribed icing procedures. No icing was forecast for the area en route, and no 'known icing' was entered.

Original NASA ASRS Text

Title: C-172 ENCOUNTERS INFLT ICING DURING A NIGHT OP XCOUNTRY TRAINING FLT.

Narrative: I WAS FLYING AS PIC AS AN IFR STUDENT, WITH MY INSTRUCTOR IN THE R SEAT. ENRTE AT 8000 FT FROM NASHVILLE, WE SAW THE CLOUD TOPS SLOWLY RISE FROM 6000-7000 FT ON UP TO 8000 FT MSL. WE ASKED FOR, AND WERE GIVEN, 10000 FT AS A CRUISING ALT. THE CLOUDS CONTINUED THEIR GENTLE UPSLOPE, AND WE BEGAN TO BRUSH THEM AGAIN. WE ASKED FOR 11000 FT, THEN LATER 12000 FT FROM ATC. AS WE BEGAN TO PENETRATE THE CLOUDS AT 12000 FT, WE BOTH NOTICED ICE (RIME) FORMING ON THE WING STRUTS. BY THE TIME WE WERE CLRED TO 8000 FT (TO ATTEMPT TO DSND OUT OF THE ICING ENVIRONMENT), WE WERE PICKING UP MODERATE RIME ICE. DSNDING TOWARD 8000 FT, WE NOTIFIED ATC THAT THE ICING WAS MODERATE TO SEVERE RIME, AND REQUESTED 3000 FT. UPON REACHING 3000 FT (AND LATER 2500 FT), OUR 1/2 INCH ICE ON THE WINGS FELL OFF GRADUALLY. CTL OF THE ACFT WAS NEVER LOST, NO REGULATIONS WERE BROKEN, AND NO HAZARD TO OURSELVES OR OTHER ACFT WAS EXPERIENCED. MY ACTIONS WERE CONSISTENT WITH PRESCRIBED ICING PROCS. NO ICING WAS FORECAST FOR THE AREA ENRTE, AND NO 'KNOWN ICING' WAS ENTERED.

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.