A PA28-180 archer pilot found himself with a serious load of airframe ice.

Attributes
ACN	357017
Time
Date	199612
Day	Sun
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : grr
State Reference	ME
Altitude	msl bound lower : 3000 msl bound upper : 4000
Environment
Flight Conditions	Mixed
Light	Dusk
Aircraft 1
Controlling Facilities	tracon : grr tower : sav
Operator	general aviation : personal
Make Model Name	Small Aircraft, Low Wing, 1 Eng, Fixed Gear
Flight Phase	climbout : intermediate altitude descent other
Route In Use	arrival other departure other
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : private pilot : instrument
Experience	flight time last 90 days : 30 flight time total : 500 flight time type : 40
ASRS Report	357017
Person 2
Affiliation	government : faa
Function	controller : radar
Qualification	controller : radar
Events
Anomaly	inflight encounter : weather non adherence : far
Independent Detector	other flight crewa
Resolutory Action	none taken : anomaly accepted
Consequence	Other
Supplementary
Primary Problem	Weather
Air Traffic Incident	Pilot Deviation

Narrative:

Moderate icing was accumulated in both the climb and descent in a light, unprotected airplane. Forecasts indicated a chance of light to moderate icing in clouds below 14000 ft. First 2 briefings indicated no PIREPS for actual ice. Third briefing prior to departure showed 2 PIREPS for ice. One out of lansing was for a trace, the other out of battle creek was for light to moderate, in the climb. Departure WX was 1600 ft overcast, tops at 4000 ft. Forecast for destination was 1500 ft overcast, occasional 2500 ft overcast, tops 4000 ft, visibility 10+ mi. I picked up 1 inch of ice on the climb out, and again in the descent. No control problems with our light load. I had no idea that ice could accumulated so rapidly. We stayed on top to sublimate ice from climb out before descent. Reasons: 1) lack of knowledge about icing accumulation rates for exposure. 2) forecasts in michigan almost always include a chance of ice in winter. Often there is none.

Original NASA ASRS Text

Title: A PA28-180 ARCHER PLT FOUND HIMSELF WITH A SERIOUS LOAD OF AIRFRAME ICE.

Narrative: MODERATE ICING WAS ACCUMULATED IN BOTH THE CLB AND DSCNT IN A LIGHT, UNPROTECTED AIRPLANE. FORECASTS INDICATED A CHANCE OF LIGHT TO MODERATE ICING IN CLOUDS BELOW 14000 FT. FIRST 2 BRIEFINGS INDICATED NO PIREPS FOR ACTUAL ICE. THIRD BRIEFING PRIOR TO DEP SHOWED 2 PIREPS FOR ICE. ONE OUT OF LANSING WAS FOR A TRACE, THE OTHER OUT OF BATTLE CREEK WAS FOR LIGHT TO MODERATE, IN THE CLB. DEP WX WAS 1600 FT OVCST, TOPS AT 4000 FT. FORECAST FOR DEST WAS 1500 FT OVCST, OCCASIONAL 2500 FT OVCST, TOPS 4000 FT, VISIBILITY 10+ MI. I PICKED UP 1 INCH OF ICE ON THE CLB OUT, AND AGAIN IN THE DSCNT. NO CTL PROBS WITH OUR LIGHT LOAD. I HAD NO IDEA THAT ICE COULD ACCUMULATED SO RAPIDLY. WE STAYED ON TOP TO SUBLIMATE ICE FROM CLB OUT BEFORE DSCNT. REASONS: 1) LACK OF KNOWLEDGE ABOUT ICING ACCUMULATION RATES FOR EXPOSURE. 2) FORECASTS IN MICHIGAN ALMOST ALWAYS INCLUDE A CHANCE OF ICE IN WINTER. OFTEN THERE IS NONE.

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.